mirror of https://github.com/perkeep/perkeep.git
remove the db and dbimpl packages; now in the Go core as database/sql and database/sql/driver
Change-Id: Ie88df6466f9b81e4320895049dd3611c43e0ea4a
This commit is contained in:
Brad Fitzpatrick
parent
a1e4d063f4
commit
1026c32f06
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@ -1,118 +0,0 @@
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/*
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Copyright 2011 Google Inc.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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|
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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// Type conversions for Scan.
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package db
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import (
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"errors"
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"fmt"
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"reflect"
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"strconv"
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)
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// copyConvert copies to dest the value in src, converting it if possible
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// An error is returned if the copy would result in loss of information.
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// dest should be a pointer type.
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func copyConvert(dest, src interface{}) error {
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// Common cases, without reflect. Fall through.
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switch s := src.(type) {
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case string:
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switch d := dest.(type) {
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case *string:
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*d = s
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return nil
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}
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case []byte:
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switch d := dest.(type) {
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case *string:
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*d = string(s)
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return nil
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case *[]byte:
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*d = s
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return nil
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}
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}
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sv := reflect.ValueOf(src)
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switch d := dest.(type) {
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case *string:
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switch sv.Kind() {
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case reflect.Bool,
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reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
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reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64,
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reflect.Float32, reflect.Float64:
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*d = fmt.Sprintf("%v", src)
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return nil
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}
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}
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if scanner, ok := dest.(ScannerInto); ok {
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return scanner.ScanInto(src)
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}
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dpv := reflect.ValueOf(dest)
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if dpv.Kind() != reflect.Ptr {
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return errors.New("destination not a pointer")
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}
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dv := reflect.Indirect(dpv)
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if dv.Kind() == sv.Kind() {
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dv.Set(sv)
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return nil
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}
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switch dv.Kind() {
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case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
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if s, ok := asString(src); ok {
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i64, err := strconv.ParseInt(s, 10, 64)
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if err != nil {
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return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err)
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}
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if dv.OverflowInt(i64) {
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return fmt.Errorf("string %q overflows %s", s, dv.Kind())
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}
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dv.SetInt(i64)
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return nil
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}
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case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
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if s, ok := asString(src); ok {
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u64, err := strconv.ParseUint(s, 10, 64)
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if err != nil {
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return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err)
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}
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if dv.OverflowUint(u64) {
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return fmt.Errorf("string %q overflows %s", s, dv.Kind())
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}
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dv.SetUint(u64)
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return nil
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}
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}
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return fmt.Errorf("unsupported driver -> Scan pair: %T -> %T", src, dest)
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}
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func asString(src interface{}) (s string, ok bool) {
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switch v := src.(type) {
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case string:
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return v, true
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case []byte:
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return string(v), true
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}
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return "", false
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}
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@ -1,120 +0,0 @@
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/*
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Copyright 2011 Google Inc.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package db
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import (
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"fmt"
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"reflect"
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"testing"
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)
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type conversionTest struct {
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s, d interface{} // source and destination
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// following are used if they're non-zero
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wantint int64
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wantuint uint64
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wantstr string
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wanterr string
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}
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// Target variables for scanning into.
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var (
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scanstr string
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scanint int
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scanint8 int8
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scanint16 int16
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scanint32 int32
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scanuint8 uint8
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scanuint16 uint16
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)
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var conversionTests = []conversionTest{
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// Exact conversions (destination pointer type matches source type)
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{s: "foo", d: &scanstr, wantstr: "foo"},
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{s: 123, d: &scanint, wantint: 123},
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// To strings
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{s: []byte("byteslice"), d: &scanstr, wantstr: "byteslice"},
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{s: 123, d: &scanstr, wantstr: "123"},
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{s: int8(123), d: &scanstr, wantstr: "123"},
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{s: int64(123), d: &scanstr, wantstr: "123"},
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{s: uint8(123), d: &scanstr, wantstr: "123"},
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{s: uint16(123), d: &scanstr, wantstr: "123"},
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{s: uint32(123), d: &scanstr, wantstr: "123"},
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{s: uint64(123), d: &scanstr, wantstr: "123"},
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{s: 1.5, d: &scanstr, wantstr: "1.5"},
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// Strings to integers
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{s: "255", d: &scanuint8, wantuint: 255},
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{s: "256", d: &scanuint8, wanterr: `string "256" overflows uint8`},
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{s: "256", d: &scanuint16, wantuint: 256},
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{s: "-1", d: &scanint, wantint: -1},
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{s: "foo", d: &scanint, wanterr: `converting string "foo" to a int: parsing "foo": invalid argument`},
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}
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func intValue(intptr interface{}) int64 {
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return reflect.Indirect(reflect.ValueOf(intptr)).Int()
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}
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func uintValue(intptr interface{}) uint64 {
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return reflect.Indirect(reflect.ValueOf(intptr)).Uint()
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}
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func TestConversions(t *testing.T) {
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for n, ct := range conversionTests {
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err := copyConvert(ct.d, ct.s)
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errstr := ""
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if err != nil {
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errstr = err.String()
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}
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errf := func(format string, args ...interface{}) {
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base := fmt.Sprintf("copyConvert #%d: for %v (%T) -> %T, ", n, ct.s, ct.s, ct.d)
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t.Errorf(base+format, args...)
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}
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if errstr != ct.wanterr {
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errf("got error %q, want error %q", errstr, ct.wanterr)
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}
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if ct.wantstr != "" && ct.wantstr != scanstr {
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errf("want string %q, got %q", ct.wantstr, scanstr)
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}
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if ct.wantint != 0 && ct.wantint != intValue(ct.d) {
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errf("want int %d, got %d", ct.wantint, intValue(ct.d))
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}
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if ct.wantuint != 0 && ct.wantuint != uintValue(ct.d) {
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errf("want uint %d, got %d", ct.wantuint, uintValue(ct.d))
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}
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}
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}
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func TestNullableString(t *testing.T) {
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var ns NullableString
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copyConvert(&ns, []byte("foo"))
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if !ns.Ok {
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t.Errorf("expecting ok")
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}
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if ns.String != "foo" {
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t.Errorf("expecting foo; got %q", ns.String)
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}
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copyConvert(&ns, nil)
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if ns.Ok {
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t.Errorf("expecting not ok on nil")
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}
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if ns.String != "" {
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t.Errorf("expecting blank on nil; got %q", ns.String)
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}
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}
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541
pkg/db/db.go
541
pkg/db/db.go
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@ -1,541 +0,0 @@
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/*
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Copyright 2011 Google Inc.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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|
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http://www.apache.org/licenses/LICENSE-2.0
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|
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
|
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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// Package db provides a generic interface around SQL (or SQL-like)
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// databases.
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package db
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import (
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"errors"
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"fmt"
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"io"
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"runtime"
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"sync"
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"camlistore.org/pkg/db/dbimpl"
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)
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var drivers = make(map[string]dbimpl.Driver)
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// Register makes a database driver available by the provided name.
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// It's a fatal error to register the same or different drivers with
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// a duplicate name.
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func Register(name string, driver dbimpl.Driver) {
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if driver == nil {
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panic("db: Register driver is nil")
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}
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if _, dup := drivers[name]; dup {
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panic("db: Register called twice for driver " + name)
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}
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drivers[name] = driver
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}
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// NullableString is type representing a string which may be
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// null. NullableString implements the ScannerInto inteface so can be
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// used as a scan destination:
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//
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// var s NullableString
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// err := db.QueryRow("SELECT name FROM foo WHERE id=?", id).Scan(&s)
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// ...
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// if !s.Ok {
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// // NULL value
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// } else {
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// // use s.String
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// }
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//
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// TODO(bradfitz): add other types.
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type NullableString struct {
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String string
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Ok bool // Ok is true if the String is not NULL
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}
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// ScanInto implements the ScannerInto interface.
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func (ms *NullableString) ScanInto(value interface{}) error {
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if value == nil {
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ms.String, ms.Ok = "", false
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return nil
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}
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ms.Ok = true
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return copyConvert(&ms.String, value)
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}
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// ScannerInto is an interface used by Scan.
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type ScannerInto interface {
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// value is nil for NULL database columns.
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ScanInto(value interface{}) error
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}
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// ErrNoRows is returned by Scan when QueryRow doesn't return a
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// row. In such a case, QueryRow returns a placeholder *Row value that
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// defers this error until a Scan.
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var ErrNoRows = errors.New("db: no rows in result set")
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// DB is a database handle. It's safe for concurrent use by multiple
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// goroutines.
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type DB struct {
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driver dbimpl.Driver
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dsn string
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mu sync.Mutex
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freeConn []dbimpl.Conn
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}
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// Open opens a database specified by its database driver name and a
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// driver-specific data source name, usually consisting of at least a
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// database name and connection information.
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//
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// Most users will open a database via a driver-specific connection
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// helper function that returns a *DB.
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func Open(driverName, dataSourceName string) (*DB, error) {
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driver, ok := drivers[driverName]
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if !ok {
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return nil, fmt.Errorf("db: unknown driver %q (forgotten import?)", driverName)
|
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}
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return &DB{driver: driver, dsn: dataSourceName}, nil
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}
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func (db *DB) maxIdleConns() int {
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const defaultMaxIdleConns = 2
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// TODO(bradfitz): ask driver, if supported, for its default preference
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// TODO(bradfitz): let users override?
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return defaultMaxIdleConns
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}
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// conn returns a newly-opened or cached dbimpl.Conn
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func (db *DB) conn() (dbimpl.Conn, error) {
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db.mu.Lock()
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if n := len(db.freeConn); n > 0 {
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conn := db.freeConn[n-1]
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db.freeConn = db.freeConn[:n-1]
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db.mu.Unlock()
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return conn, nil
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}
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db.mu.Unlock()
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return db.driver.Open(db.dsn)
|
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}
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|
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func (db *DB) connIfFree(wanted dbimpl.Conn) (conn dbimpl.Conn, ok bool) {
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db.mu.Lock()
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defer db.mu.Unlock()
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for n, conn := range db.freeConn {
|
||||
if conn == wanted {
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db.freeConn[n] = db.freeConn[len(db.freeConn)-1]
|
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db.freeConn = db.freeConn[:len(db.freeConn)-1]
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return wanted, true
|
||||
}
|
||||
}
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return nil, false
|
||||
}
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func (db *DB) putConn(c dbimpl.Conn) {
|
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if n := len(db.freeConn); n < db.maxIdleConns() {
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db.freeConn = append(db.freeConn, c)
|
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return
|
||||
}
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db.closeConn(c)
|
||||
}
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|
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func (db *DB) closeConn(c dbimpl.Conn) {
|
||||
// TODO: check to see if we need this Conn for any prepared statements
|
||||
// that are active.
|
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c.Close()
|
||||
}
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||||
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func (db *DB) Prepare(query string) (*Stmt, error) {
|
||||
// TODO: check if db.driver supports an optional
|
||||
// dbimpl.Preparer interface and call that instead, if so,
|
||||
// otherwise we make a prepared statement that's bound
|
||||
// to a connection, and to execute this prepared statement
|
||||
// we either need to use this connection (if it's free), else
|
||||
// get a new connection + re-prepare + execute on that one.
|
||||
ci, err := db.conn()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer db.putConn(ci)
|
||||
si, err := ci.Prepare(query)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
stmt := &Stmt{
|
||||
db: db,
|
||||
query: query,
|
||||
css: []connStmt{{ci, si}},
|
||||
}
|
||||
return stmt, nil
|
||||
}
|
||||
|
||||
func (db *DB) Exec(query string, args ...interface{}) (Result, error) {
|
||||
// Optional fast path, if the driver implements dbimpl.Execer.
|
||||
if execer, ok := db.driver.(dbimpl.Execer); ok {
|
||||
resi, err := execer.Exec(query, args)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return result{resi}, nil
|
||||
}
|
||||
|
||||
// If the driver does not implement dbimpl.Execer, we need
|
||||
// a connection.
|
||||
conn, err := db.conn()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer db.putConn(conn)
|
||||
|
||||
if execer, ok := conn.(dbimpl.Execer); ok {
|
||||
resi, err := execer.Exec(query, args)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return result{resi}, nil
|
||||
}
|
||||
|
||||
sti, err := conn.Prepare(query)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer sti.Close()
|
||||
resi, err := sti.Exec(args)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return result{resi}, nil
|
||||
}
|
||||
|
||||
func (db *DB) Query(query string, args ...interface{}) (*Rows, error) {
|
||||
stmt, err := db.Prepare(query)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer stmt.Close()
|
||||
return stmt.Query(args...)
|
||||
}
|
||||
|
||||
func (db *DB) QueryRow(query string, args ...interface{}) *Row {
|
||||
rows, err := db.Query(query, args...)
|
||||
if err != nil {
|
||||
return &Row{err: err}
|
||||
}
|
||||
return &Row{rows: rows}
|
||||
}
|
||||
|
||||
func (db *DB) Begin() (*Tx, error) {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
// DriverDatabase returns the database's underlying driver.
|
||||
// This is non-portable and should only be used when
|
||||
// needed.
|
||||
func (db *DB) Driver() dbimpl.Driver {
|
||||
return db.driver
|
||||
}
|
||||
|
||||
// Tx is an in-progress database transaction.
|
||||
type Tx struct {
|
||||
}
|
||||
|
||||
func (tx *Tx) Commit() error {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
func (tx *Tx) Rollback() error {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
func (tx *Tx) Prepare(query string) (*Stmt, error) {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
func (tx *Tx) Exec(query string, args ...interface{}) {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
func (tx *Tx) Query(query string, args ...interface{}) (*Rows, error) {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
func (tx *Tx) QueryRow(query string, args ...interface{}) *Row {
|
||||
panic(todo())
|
||||
}
|
||||
|
||||
// connStmt is a prepared statement on a particular connection.
|
||||
type connStmt struct {
|
||||
ci dbimpl.Conn
|
||||
si dbimpl.Stmt
|
||||
}
|
||||
|
||||
// Stmt is a prepared statement. Stmt is safe for concurrent use by multiple goroutines.
|
||||
type Stmt struct {
|
||||
// Immutable:
|
||||
db *DB // where we came from
|
||||
query string // that created the Sttm
|
||||
|
||||
mu sync.Mutex
|
||||
closed bool
|
||||
css []connStmt // can use any that have idle connections
|
||||
}
|
||||
|
||||
func todo() string {
|
||||
_, file, line, _ := runtime.Caller(1)
|
||||
return fmt.Sprintf("%s:%d: TODO: implement", file, line)
|
||||
}
|
||||
|
||||
func (s *Stmt) Exec(args ...interface{}) (Result, error) {
|
||||
ci, si, err := s.connStmt()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
defer s.db.putConn(ci)
|
||||
|
||||
if want := si.NumInput(); len(args) != want {
|
||||
return nil, fmt.Errorf("db: expected %d arguments, got %d", want, len(args))
|
||||
}
|
||||
|
||||
// Convert args if the driver knows its own types.
|
||||
if cc, ok := si.(dbimpl.ColumnConverter); ok {
|
||||
for n, arg := range args {
|
||||
args[n], err = cc.ColumnCoverter(n).ConvertValue(arg)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("db: converting Exec column index %d: %v", n, err)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Then convert everything into the restricted subset
|
||||
// of types that the dbimpl package needs to know about.
|
||||
// all integers -> int64, etc
|
||||
for n, arg := range args {
|
||||
var err error
|
||||
args[n], err = dbimpl.SubsetValue(arg)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("db: error converting index %d: %v", n, err)
|
||||
}
|
||||
}
|
||||
|
||||
resi, err := si.Exec(args)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return result{resi}, nil
|
||||
}
|
||||
|
||||
func (s *Stmt) connStmt(args ...interface{}) (dbimpl.Conn, dbimpl.Stmt, error) {
|
||||
s.mu.Lock()
|
||||
if s.closed {
|
||||
return nil, nil, errors.New("db: statement is closed")
|
||||
}
|
||||
var cs connStmt
|
||||
match := false
|
||||
for _, v := range s.css {
|
||||
// TODO(bradfitz): lazily clean up entries in this
|
||||
// list with dead conns while enumerating
|
||||
if _, match = s.db.connIfFree(cs.ci); match {
|
||||
cs = v
|
||||
break
|
||||
}
|
||||
}
|
||||
s.mu.Unlock()
|
||||
|
||||
// Make a new conn if all are busy.
|
||||
// TODO(bradfitz): or wait for one? make configurable later?
|
||||
if !match {
|
||||
ci, err := s.db.conn()
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
si, err := ci.Prepare(s.query)
|
||||
if err != nil {
|
||||
return nil, nil, err
|
||||
}
|
||||
s.mu.Lock()
|
||||
cs = connStmt{ci, si}
|
||||
s.css = append(s.css, cs)
|
||||
s.mu.Unlock()
|
||||
}
|
||||
|
||||
return cs.ci, cs.si, nil
|
||||
}
|
||||
|
||||
// Query executes a prepared statement with the provided placeholder arguments
|
||||
// and returns the result.
|
||||
func (s *Stmt) Query(args ...interface{}) (*Rows, error) {
|
||||
ci, si, err := s.connStmt(args...)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if len(args) != si.NumInput() {
|
||||
return nil, fmt.Errorf("db: statement expects %d inputs; got %d", si.NumInput(), len(args))
|
||||
}
|
||||
rowsi, err := si.Query(args)
|
||||
if err != nil {
|
||||
s.db.putConn(ci)
|
||||
return nil, err
|
||||
}
|
||||
// Note: ownership of ci passes to the *Rows
|
||||
rows := &Rows{
|
||||
db: s.db,
|
||||
ci: ci,
|
||||
rowsi: rowsi,
|
||||
}
|
||||
return rows, nil
|
||||
}
|
||||
|
||||
// QueryRow wraps Query, for use in selecting a single row. Any errors
|
||||
// are deferred until the returned row is scanned. The returned row is
|
||||
// always non-nil.
|
||||
func (s *Stmt) QueryRow(args ...interface{}) *Row {
|
||||
rows, err := s.Query(args...)
|
||||
if err != nil {
|
||||
return &Row{err: err}
|
||||
}
|
||||
return &Row{rows: rows}
|
||||
}
|
||||
|
||||
func (s *Stmt) Close() error {
|
||||
s.mu.Lock()
|
||||
defer s.mu.Unlock() // TODO(bradfitz): move this unlock after 'closed = true'?
|
||||
if s.closed {
|
||||
return nil
|
||||
}
|
||||
s.closed = true
|
||||
for _, v := range s.css {
|
||||
if ci, match := s.db.connIfFree(v.ci); match {
|
||||
v.si.Close()
|
||||
s.db.putConn(ci)
|
||||
} else {
|
||||
// TODO(bradfitz): care that we can't close
|
||||
// this statement because the statement's
|
||||
// connection is in use?
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Rows is the result of a query. Its cursor starts before the first row
|
||||
// of the result set. Use Next to advance through the rows:
|
||||
//
|
||||
// rows, err := db.Query("SELECT ...")
|
||||
// ...
|
||||
// for rows.Next() {
|
||||
// var id int
|
||||
// var name string
|
||||
// err = rows.Scan(&id, &name)
|
||||
// ...
|
||||
// }
|
||||
// err = rows.Error() // get any Error encountered during iteration
|
||||
// ...
|
||||
type Rows struct {
|
||||
db *DB
|
||||
ci dbimpl.Conn // owned; must be returned when Rows is closed
|
||||
rowsi dbimpl.Rows
|
||||
|
||||
closed bool
|
||||
lastcols []interface{}
|
||||
lasterr error
|
||||
}
|
||||
|
||||
// Next advances the Rows' cursor (which starts before the first
|
||||
// row). Next returns true if there's another row and the cursor was
|
||||
// moved.
|
||||
func (rs *Rows) Next() bool {
|
||||
if rs.closed {
|
||||
return false
|
||||
}
|
||||
if rs.lasterr != nil {
|
||||
return false
|
||||
}
|
||||
if rs.lastcols == nil {
|
||||
rs.lastcols = make([]interface{}, len(rs.rowsi.Columns()))
|
||||
}
|
||||
rs.lasterr = rs.rowsi.Next(rs.lastcols)
|
||||
return rs.lasterr == nil
|
||||
}
|
||||
|
||||
// Error returns the error, if any, that was encountered during iteration.
|
||||
func (rs *Rows) Error() error {
|
||||
if rs.lasterr == io.EOF {
|
||||
return nil
|
||||
}
|
||||
return rs.lasterr
|
||||
}
|
||||
|
||||
// Scan copies the columns in the current row into variables referened in dest.
|
||||
func (rs *Rows) Scan(dest ...interface{}) error {
|
||||
if rs.closed {
|
||||
return errors.New("db: Rows closed")
|
||||
}
|
||||
if rs.lasterr != nil {
|
||||
return rs.lasterr
|
||||
}
|
||||
if rs.lastcols == nil {
|
||||
return errors.New("db: Scan called without calling Next")
|
||||
}
|
||||
if len(dest) != len(rs.lastcols) {
|
||||
return fmt.Errorf("db: expected %d destination arguments in Scan, not %d", len(rs.lastcols), len(dest))
|
||||
}
|
||||
for i, sv := range rs.lastcols {
|
||||
err := copyConvert(dest[i], sv)
|
||||
if err != nil {
|
||||
return fmt.Errorf("db: Scan error on column index %d: %v", i, err)
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// Close closes the Rows, preventing further enumeration. If the end
|
||||
// if encountered normally the Rows are closed automatically. Calling
|
||||
// Close is idempotent.
|
||||
func (rs *Rows) Close() error {
|
||||
if rs.closed {
|
||||
return nil
|
||||
}
|
||||
rs.closed = true
|
||||
err := rs.rowsi.Close()
|
||||
rs.db.putConn(rs.ci)
|
||||
return err
|
||||
}
|
||||
|
||||
// Row is the result of calling QueryRow to select a single row. If no
|
||||
// matching row was found, an error is deferred until the Scan method
|
||||
// is called.
|
||||
type Row struct {
|
||||
// One of these two will be non-nil:
|
||||
err error // deferred error for easy chaining
|
||||
rows *Rows
|
||||
}
|
||||
|
||||
// Scan copies the columns from the matched row into the variables
|
||||
// pointed at in dest. If no row was matched, ErrNoRows is returned.
|
||||
func (r *Row) Scan(dest ...interface{}) error {
|
||||
if r.err != nil {
|
||||
return r.err
|
||||
}
|
||||
defer r.rows.Close()
|
||||
if !r.rows.Next() {
|
||||
return ErrNoRows
|
||||
}
|
||||
return r.rows.Scan(dest...)
|
||||
}
|
||||
|
||||
type Result interface {
|
||||
AutoIncrementId() (int64, error)
|
||||
RowsAffected() (int64, error)
|
||||
}
|
||||
|
||||
type result struct {
|
||||
dbimpl.Result
|
||||
}
|
||||
|
|
@ -1,154 +0,0 @@
|
|||
/*
|
||||
Copyright 2011 Google Inc.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package db
|
||||
|
||||
import (
|
||||
"strings"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func newTestDB(t *testing.T, name string) *DB {
|
||||
db, err := Open("test", "foo")
|
||||
if err != nil {
|
||||
t.Fatalf("Open: %v", err)
|
||||
}
|
||||
if _, err := db.Exec("WIPE"); err != nil {
|
||||
t.Fatalf("exec wipe: %v", err)
|
||||
}
|
||||
if name == "people" {
|
||||
exec(t, db, "CREATE|people|name=string,age=int32,dead=bool")
|
||||
exec(t, db, "INSERT|people|name=Alice,age=?", 1)
|
||||
exec(t, db, "INSERT|people|name=Bob,age=?", 2)
|
||||
exec(t, db, "INSERT|people|name=Chris,age=?", 3)
|
||||
|
||||
}
|
||||
return db
|
||||
}
|
||||
|
||||
func exec(t *testing.T, db *DB, query string, args ...interface{}) {
|
||||
_, err := db.Exec(query, args...)
|
||||
if err != nil {
|
||||
t.Fatalf("Exec of %q: %v", query, err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestQuery(t *testing.T) {
|
||||
db := newTestDB(t, "people")
|
||||
var name string
|
||||
var age int
|
||||
|
||||
err := db.QueryRow("SELECT|people|age,name|age=?", 3).Scan(&age)
|
||||
if err == nil || !strings.Contains(err.String(), "expected 2 destination arguments") {
|
||||
t.Errorf("expected error from wrong number of arguments; actually got: %v", err)
|
||||
}
|
||||
|
||||
err = db.QueryRow("SELECT|people|age,name|age=?", 2).Scan(&age, &name)
|
||||
if err != nil {
|
||||
t.Fatalf("age QueryRow+Scan: %v", err)
|
||||
}
|
||||
if name != "Bob" {
|
||||
t.Errorf("expected name Bob, got %q", name)
|
||||
}
|
||||
if age != 2 {
|
||||
t.Errorf("expected age 2, got %d", age)
|
||||
}
|
||||
|
||||
err = db.QueryRow("SELECT|people|age,name|name=?", "Alice").Scan(&age, &name)
|
||||
if err != nil {
|
||||
t.Fatalf("name QueryRow+Scan: %v", err)
|
||||
}
|
||||
if name != "Alice" {
|
||||
t.Errorf("expected name Alice, got %q", name)
|
||||
}
|
||||
if age != 1 {
|
||||
t.Errorf("expected age 1, got %d", age)
|
||||
}
|
||||
}
|
||||
|
||||
func TestStatementQueryRow(t *testing.T) {
|
||||
db := newTestDB(t, "people")
|
||||
stmt, err := db.Prepare("SELECT|people|age|name=?")
|
||||
if err != nil {
|
||||
t.Fatalf("Prepare: %v", err)
|
||||
}
|
||||
var age int
|
||||
for n, tt := range []struct{name string;want int}{
|
||||
{"Alice", 1},
|
||||
{"Bob", 2},
|
||||
{"Chris", 3},
|
||||
}{
|
||||
if err := stmt.QueryRow(tt.name).Scan(&age); err != nil {
|
||||
t.Errorf("%d: on %q, QueryRow/Scan: %v", n, tt.name, err)
|
||||
} else if age != tt.want {
|
||||
t.Errorf("%d: age=%d, want %d", age, tt.want)
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
// just a test of fakedb itself
|
||||
func TestBogusPreboundParameters(t *testing.T) {
|
||||
db := newTestDB(t, "foo")
|
||||
exec(t, db, "CREATE|t1|name=string,age=int32,dead=bool")
|
||||
_, err := db.Prepare("INSERT|t1|name=?,age=bogusconversion")
|
||||
if err == nil {
|
||||
t.Fatalf("expected error")
|
||||
}
|
||||
if err.String() != `fakedb: invalid conversion to int32 from "bogusconversion"` {
|
||||
t.Errorf("unexpected error: %v", err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestDb(t *testing.T) {
|
||||
db := newTestDB(t, "foo")
|
||||
exec(t, db, "CREATE|t1|name=string,age=int32,dead=bool")
|
||||
stmt, err := db.Prepare("INSERT|t1|name=?,age=?")
|
||||
if err != nil {
|
||||
t.Errorf("Stmt, err = %v, %v", stmt, err)
|
||||
}
|
||||
|
||||
type execTest struct {
|
||||
args []interface{}
|
||||
wantErr string
|
||||
}
|
||||
execTests := []execTest{
|
||||
// Okay:
|
||||
{[]interface{}{"Brad", 31}, ""},
|
||||
{[]interface{}{"Brad", int64(31)}, ""},
|
||||
{[]interface{}{"Bob", "32"}, ""},
|
||||
{[]interface{}{7, 9}, ""},
|
||||
|
||||
// Invalid conversions:
|
||||
{[]interface{}{"Brad", int64(0xFFFFFFFF)}, "db: converting Exec column index 1: value 4294967295 overflows int32"},
|
||||
{[]interface{}{"Brad", "strconv fail"}, "db: converting Exec column index 1: value \"strconv fail\" can't be converted to int32"},
|
||||
|
||||
// Wrong number of args:
|
||||
{[]interface{}{}, "db: expected 2 arguments, got 0"},
|
||||
{[]interface{}{1, 2, 3}, "db: expected 2 arguments, got 3"},
|
||||
}
|
||||
for n, et := range execTests {
|
||||
_, err := stmt.Exec(et.args...)
|
||||
errStr := ""
|
||||
if err != nil {
|
||||
errStr = err.String()
|
||||
}
|
||||
if errStr != et.wantErr {
|
||||
t.Errorf("stmt.Execute #%d: for %v, got error %q, want error %q",
|
||||
n, et.args, errStr, et.wantErr)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -1,131 +0,0 @@
|
|||
/*
|
||||
Copyright 2011 Google Inc.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
// Package dbimpl defines interfaces to be implemented by database
|
||||
// drivers as used by package db.
|
||||
//
|
||||
// Code simply using databases should use package db.
|
||||
package dbimpl
|
||||
|
||||
import "errors"
|
||||
|
||||
// must only deal with values:
|
||||
// int64 (no uint64 support, for now?)
|
||||
// float64
|
||||
// bool
|
||||
// nil
|
||||
// []byte
|
||||
|
||||
// Driver is the interface that must be implemented by database
|
||||
// driver.
|
||||
type Driver interface {
|
||||
// Open returns a new or cached connection to the database.
|
||||
// The dsn parameter, the Data Source Name, contains a
|
||||
// driver-specific string containing the database name,
|
||||
// connection parameters, authentication parameters, etc.
|
||||
//
|
||||
// The returned connection is only used by one goroutine at a
|
||||
// time.
|
||||
Open(dsn string) (Conn, error)
|
||||
}
|
||||
|
||||
// Execer is an optional interface that may be implemented by a Driver
|
||||
// or a Conn.
|
||||
//
|
||||
// If not implemented by a Driver, the db package's DB.Exec method
|
||||
// first obtains a free connection from its free pool or from the
|
||||
// driver's Open method. Execer should only be implemented by drivers
|
||||
// which can provide a more effcient implementation.
|
||||
//
|
||||
// If not implemented by a Conn, the db package's DB.Exec will first
|
||||
// prepare a query, execute the statement, and then close the
|
||||
// statement.
|
||||
type Execer interface {
|
||||
Exec(query string, args []interface{}) (Result, error)
|
||||
}
|
||||
|
||||
type Conn interface {
|
||||
// Prepare returns a prepared statement, bound to this connection.
|
||||
Prepare(query string) (Stmt, error)
|
||||
|
||||
// Close invalidates and potentially stops any current
|
||||
// prepared statements and transactions, marking this
|
||||
// connection as no longer in use. The driver may cache or
|
||||
// close its underlying connection to its database.
|
||||
Close() error
|
||||
|
||||
// Begin starts and returns a new transaction.
|
||||
Begin() (Tx, error)
|
||||
}
|
||||
|
||||
type Result interface {
|
||||
AutoIncrementId() (int64, error)
|
||||
RowsAffected() (int64, error)
|
||||
}
|
||||
|
||||
// Stmt is a prepared statement. It is bound to a Conn and not
|
||||
// used by multiple goroutines concurrently.
|
||||
type Stmt interface {
|
||||
Close() error
|
||||
NumInput() int
|
||||
Exec(args []interface{}) (Result, error)
|
||||
Query(args []interface{}) (Rows, error)
|
||||
}
|
||||
|
||||
// ColumnConverter may be optionally implemented by Stmt to signal
|
||||
// to the db package to do type conversions.
|
||||
type ColumnConverter interface {
|
||||
ColumnCoverter(idx int) ValueConverter
|
||||
}
|
||||
|
||||
type ValueConverter interface {
|
||||
ConvertValue(v interface{}) (interface{}, error)
|
||||
}
|
||||
|
||||
type Rows interface {
|
||||
Columns() []string
|
||||
Close() error
|
||||
|
||||
// Returns os.EOF at end of cursor
|
||||
Next(dest []interface{}) error
|
||||
}
|
||||
|
||||
type Tx interface {
|
||||
Commit() error
|
||||
Rollback() error
|
||||
}
|
||||
|
||||
type RowsAffected int64
|
||||
|
||||
func (RowsAffected) AutoIncrementId() (int64, error) {
|
||||
return 0, errors.New("no AutoIncrementId available")
|
||||
}
|
||||
|
||||
func (v RowsAffected) RowsAffected() (int64, error) {
|
||||
return int64(v), nil
|
||||
}
|
||||
|
||||
type ddlSuccess struct{}
|
||||
|
||||
var DDLSuccess Result = ddlSuccess{}
|
||||
|
||||
func (ddlSuccess) AutoIncrementId() (int64, error) {
|
||||
return 0, errors.New("no AutoIncrementId available after DDL statement")
|
||||
}
|
||||
|
||||
func (ddlSuccess) RowsAffected() (int64, error) {
|
||||
return 0, errors.New("no RowsAffected available after DDL statement")
|
||||
}
|
||||
|
|
@ -1,105 +0,0 @@
|
|||
/*
|
||||
Copyright 2011 Google Inc.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package dbimpl
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"reflect"
|
||||
"strconv"
|
||||
)
|
||||
|
||||
type boolType struct{}
|
||||
|
||||
var Bool = boolType{}
|
||||
|
||||
func (boolType) ConvertValue(v interface{}) (interface{}, error) {
|
||||
return nil, fmt.Errorf("TODO(bradfitz): bool conversions")
|
||||
}
|
||||
|
||||
type int32Type struct{}
|
||||
|
||||
var Int32 = int32Type{}
|
||||
|
||||
func (int32Type) ConvertValue(v interface{}) (interface{}, error) {
|
||||
rv := reflect.ValueOf(v)
|
||||
switch rv.Kind() {
|
||||
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
|
||||
i64 := rv.Int()
|
||||
if i64 > (1<<31)-1 || i64 < -(1<<31) {
|
||||
return nil, fmt.Errorf("value %d overflows int32", v)
|
||||
}
|
||||
return int32(i64), nil
|
||||
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
|
||||
u64 := rv.Uint()
|
||||
if u64 > (1<<31)-1 {
|
||||
return nil, fmt.Errorf("value %d overflows int32", v)
|
||||
}
|
||||
return int32(u64), nil
|
||||
case reflect.String:
|
||||
i, err := strconv.Atoi(rv.String())
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("value %q can't be converted to int32", v)
|
||||
}
|
||||
return int32(i), nil
|
||||
}
|
||||
return nil, fmt.Errorf("unsupported value %v (type %T) converting to int32", v, v)
|
||||
}
|
||||
|
||||
type stringType struct{}
|
||||
|
||||
var String = stringType{}
|
||||
|
||||
func (stringType) ConvertValue(v interface{}) (interface{}, error) {
|
||||
if s, ok := v.(string); ok {
|
||||
return s, nil
|
||||
}
|
||||
return fmt.Sprintf("%v", v), nil
|
||||
}
|
||||
|
||||
// SubsetValue converts v to one of the restricted subset types that
|
||||
// dbimpl drivers need to support: int64, float64, bool, nil, []byte
|
||||
func SubsetValue(v interface{}) (interface{}, error) {
|
||||
if v == nil {
|
||||
return nil, nil
|
||||
}
|
||||
if _, ok := v.([]byte); ok {
|
||||
return v, nil
|
||||
}
|
||||
if _, ok := v.(bool); ok {
|
||||
return v, nil
|
||||
}
|
||||
if s, ok := v.(string); ok {
|
||||
return []byte(s), nil
|
||||
}
|
||||
|
||||
rv := reflect.ValueOf(v)
|
||||
switch rv.Kind() {
|
||||
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
|
||||
return rv.Int(), nil
|
||||
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32:
|
||||
return int64(rv.Uint()), nil
|
||||
case reflect.Uint64:
|
||||
u64 := rv.Uint()
|
||||
if u64 >= 1<<63 {
|
||||
return nil, fmt.Errorf("uint64 values with high bit set are not supported")
|
||||
}
|
||||
return int64(u64), nil
|
||||
case reflect.Float32, reflect.Float64:
|
||||
return rv.Float(), nil
|
||||
}
|
||||
return nil, fmt.Errorf("unsupported type %s", rv.Kind())
|
||||
}
|
||||
|
|
@ -1,46 +0,0 @@
|
|||
Goals of the db and db/dbimpl packages:
|
||||
|
||||
* Provide a generic database API for a variety of SQL or SQL-like
|
||||
databases. There currently exist Go libraries for SQLite, MySQL,
|
||||
and Postgres, but all with a very different feel, and often
|
||||
a non-Go-like feel.
|
||||
|
||||
* Feel like Go.
|
||||
|
||||
* Care mostly about the common cases. Common SQL should be portable.
|
||||
SQL edge cases or db-specific extensions can be detected and
|
||||
conditionally used by the application. It is a non-goal to care
|
||||
about every particular db's extension or quirk.
|
||||
|
||||
* Separate out the basic implementation of a database driver
|
||||
(implementing the db/dbimpl interfaces) vs the implementation
|
||||
of all the user-level types and convenience methods.
|
||||
In a nutshell:
|
||||
|
||||
User Code ---> db package (concrete types) ---> db/dbimpl (interfaces)
|
||||
Database Driver -> db (to register) + dbimpl (implement interfaces)
|
||||
|
||||
* To type casting/conversions consistently between all drivers. To
|
||||
achieve this, most of the type conversions are done in the db
|
||||
package, not in each driver. The drivers then only have to deal
|
||||
with a smaller set of types.
|
||||
|
||||
* Be flexible with type conversions, but be paranoid about silent
|
||||
truncation or other loss of precision.
|
||||
|
||||
* Handle concurrency well. Users shouldn't need to care about the
|
||||
database's per-connection thread safety issues (or lack thereof),
|
||||
and shouldn't have to maintain their own free pools of connections.
|
||||
The 'db' package should deal with that bookkeeping as needed. Given
|
||||
a *db.DB, it should be possible to share that instance between
|
||||
multiple goroutines, without any extra synchronization.
|
||||
|
||||
* Push complexity, where necessary, down into the db+dbimpl packages,
|
||||
rather than exposing it to users. Said otherwise, the db package
|
||||
should expose an ideal database that's not finnicky about how it's
|
||||
accessed, even if that's not true.
|
||||
|
||||
* Provide optional interfaces in dbimpl for drivers to implement
|
||||
for special cases or fastpaths. But the only party that knows about
|
||||
those is the 'db' package. To user code, some stuff just might start
|
||||
working or start working slightly faster.
|
||||
|
|
@ -1,511 +0,0 @@
|
|||
/*
|
||||
Copyright 2011 Google Inc.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package db
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"io"
|
||||
"log"
|
||||
"strconv"
|
||||
"strings"
|
||||
"sync"
|
||||
|
||||
"camlistore.org/pkg/db/dbimpl"
|
||||
)
|
||||
|
||||
var _ = log.Printf
|
||||
|
||||
// fakeDriver is a fake database that implements Go's dbimpl.Driver
|
||||
// interface, just for testing.
|
||||
//
|
||||
// It speaks a query language that's semantically similar to but
|
||||
// syntantically different and simpler than SQL. The syntax is as
|
||||
// follows:
|
||||
//
|
||||
// WIPE
|
||||
// CREATE|<tablename>|<col>=<type>,<col>=<type>,...
|
||||
// where types are: "string", [u]int{8,16,32,64}, "bool"
|
||||
// INSERT|<tablename>|col=val,col2=val2,col3=?
|
||||
// SELECT|<tablename>|projectcol1,projectcol2|filtercol=?,filtercol2=?
|
||||
//
|
||||
// When opening a a fakeDriver's database, it starts empty with no
|
||||
// tables. All tables and data are stored in memory only.
|
||||
type fakeDriver struct {
|
||||
mu sync.Mutex
|
||||
openCount int
|
||||
dbs map[string]*fakeDB
|
||||
}
|
||||
|
||||
type fakeDB struct {
|
||||
name string
|
||||
|
||||
mu sync.Mutex
|
||||
free []*fakeConn
|
||||
tables map[string]*table
|
||||
}
|
||||
|
||||
type table struct {
|
||||
mu sync.Mutex
|
||||
colname []string
|
||||
coltype []string
|
||||
rows []*row
|
||||
}
|
||||
|
||||
func (t *table) columnIndex(name string) int {
|
||||
for n, nname := range t.colname {
|
||||
if name == nname {
|
||||
return n
|
||||
}
|
||||
}
|
||||
return -1
|
||||
}
|
||||
|
||||
type row struct {
|
||||
cols []interface{} // must be same size as its table colname + coltype
|
||||
}
|
||||
|
||||
func (r *row) clone() *row {
|
||||
nrow := &row{cols: make([]interface{}, len(r.cols))}
|
||||
copy(nrow.cols, r.cols)
|
||||
return nrow
|
||||
}
|
||||
|
||||
type fakeConn struct {
|
||||
db *fakeDB // where to return ourselves to
|
||||
|
||||
currTx *fakeTx
|
||||
}
|
||||
|
||||
type fakeTx struct {
|
||||
c *fakeConn
|
||||
}
|
||||
|
||||
type fakeStmt struct {
|
||||
c *fakeConn
|
||||
q string // just for debugging
|
||||
|
||||
cmd string
|
||||
table string
|
||||
|
||||
colName []string // used by CREATE, INSERT, SELECT (selected columns)
|
||||
colType []string // used by CREATE
|
||||
colValue []interface{} // used by INSERT (mix of strings and "?" for bound params)
|
||||
placeholders int // used by INSERT/SELECT: number of ? params
|
||||
|
||||
whereCol []string // used by SELECT (all placeholders)
|
||||
|
||||
placeholderConverter []dbimpl.ValueConverter // used by INSERT
|
||||
}
|
||||
|
||||
var driver dbimpl.Driver = &fakeDriver{}
|
||||
|
||||
func init() {
|
||||
Register("test", driver)
|
||||
}
|
||||
|
||||
// Supports dsn forms:
|
||||
// <dbname>
|
||||
// <dbname>;wipe
|
||||
func (d *fakeDriver) Open(dsn string) (dbimpl.Conn, error) {
|
||||
d.mu.Lock()
|
||||
defer d.mu.Unlock()
|
||||
d.openCount++
|
||||
if d.dbs == nil {
|
||||
d.dbs = make(map[string]*fakeDB)
|
||||
}
|
||||
parts := strings.Split(dsn, ";")
|
||||
if len(parts) < 1 {
|
||||
return nil, errors.New("fakedb: no database name")
|
||||
}
|
||||
name := parts[0]
|
||||
db, ok := d.dbs[name]
|
||||
if !ok {
|
||||
db = &fakeDB{name: name}
|
||||
d.dbs[name] = db
|
||||
}
|
||||
return &fakeConn{db: db}, nil
|
||||
}
|
||||
|
||||
func (db *fakeDB) wipe() {
|
||||
db.mu.Lock()
|
||||
defer db.mu.Unlock()
|
||||
db.tables = nil
|
||||
}
|
||||
|
||||
func (db *fakeDB) createTable(name string, columnNames, columnTypes []string) error {
|
||||
db.mu.Lock()
|
||||
defer db.mu.Unlock()
|
||||
if db.tables == nil {
|
||||
db.tables = make(map[string]*table)
|
||||
}
|
||||
if _, exist := db.tables[name]; exist {
|
||||
return fmt.Errorf("table %q already exists", name)
|
||||
}
|
||||
if len(columnNames) != len(columnTypes) {
|
||||
return fmt.Errorf("create table of %q len(names) != len(types): %d vs %d",
|
||||
len(columnNames), len(columnTypes))
|
||||
}
|
||||
db.tables[name] = &table{colname: columnNames, coltype: columnTypes}
|
||||
return nil
|
||||
}
|
||||
|
||||
// must be called with db.mu lock held
|
||||
func (db *fakeDB) table(table string) (*table, bool) {
|
||||
if db.tables == nil {
|
||||
return nil, false
|
||||
}
|
||||
t, ok := db.tables[table]
|
||||
return t, ok
|
||||
}
|
||||
|
||||
func (db *fakeDB) columnType(table, column string) (typ string, ok bool) {
|
||||
db.mu.Lock()
|
||||
defer db.mu.Unlock()
|
||||
t, ok := db.table(table)
|
||||
if !ok {
|
||||
return
|
||||
}
|
||||
for n, cname := range t.colname {
|
||||
if cname == column {
|
||||
return t.coltype[n], true
|
||||
}
|
||||
}
|
||||
return "", false
|
||||
}
|
||||
|
||||
func (c *fakeConn) Begin() (dbimpl.Tx, error) {
|
||||
if c.currTx != nil {
|
||||
return nil, errors.New("already in a transaction")
|
||||
}
|
||||
c.currTx = &fakeTx{c: c}
|
||||
return c.currTx, nil
|
||||
}
|
||||
|
||||
func (c *fakeConn) Close() error {
|
||||
if c.currTx != nil {
|
||||
return errors.New("can't close; in a Transaction")
|
||||
}
|
||||
if c.db == nil {
|
||||
return errors.New("can't close; already closed")
|
||||
}
|
||||
c.db = nil
|
||||
return nil
|
||||
}
|
||||
|
||||
func errf(msg string, args ...interface{}) error {
|
||||
return errors.New("fakedb: " + fmt.Sprintf(msg, args...))
|
||||
}
|
||||
|
||||
// parts are table|selectCol1,selectCol2|whereCol=?,whereCol2=?
|
||||
// (note that where where columns must always contain ? marks,
|
||||
// just a limitation for fakedb)
|
||||
func (c *fakeConn) prepareSelect(stmt *fakeStmt, parts []string) (dbimpl.Stmt, error) {
|
||||
if len(parts) != 3 {
|
||||
return nil, errf("invalid SELECT syntax with %d parts; want 3", len(parts))
|
||||
}
|
||||
stmt.table = parts[0]
|
||||
stmt.colName = strings.Split(parts[1], ",")
|
||||
for n, colspec := range strings.Split(parts[2], ",") {
|
||||
nameVal := strings.Split(colspec, "=")
|
||||
if len(nameVal) != 2 {
|
||||
return nil, errf("SELECT on table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
|
||||
}
|
||||
column, value := nameVal[0], nameVal[1]
|
||||
_, ok := c.db.columnType(stmt.table, column)
|
||||
if !ok {
|
||||
return nil, errf("SELECT on table %q references non-existent column %q", stmt.table, column)
|
||||
}
|
||||
if value != "?" {
|
||||
return nil, errf("SELECT on table %q has pre-bound value for where column %q; need a question mark",
|
||||
stmt.table, column)
|
||||
}
|
||||
stmt.whereCol = append(stmt.whereCol, column)
|
||||
stmt.placeholders++
|
||||
}
|
||||
return stmt, nil
|
||||
}
|
||||
|
||||
// parts are table|col=type,col2=type2
|
||||
func (c *fakeConn) prepareCreate(stmt *fakeStmt, parts []string) (dbimpl.Stmt, error) {
|
||||
if len(parts) != 2 {
|
||||
return nil, errf("invalid CREATE syntax with %d parts; want 2", len(parts))
|
||||
}
|
||||
stmt.table = parts[0]
|
||||
for n, colspec := range strings.Split(parts[1], ",") {
|
||||
nameType := strings.Split(colspec, "=")
|
||||
if len(nameType) != 2 {
|
||||
return nil, errf("CREATE table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
|
||||
}
|
||||
stmt.colName = append(stmt.colName, nameType[0])
|
||||
stmt.colType = append(stmt.colType, nameType[1])
|
||||
}
|
||||
return stmt, nil
|
||||
}
|
||||
|
||||
// parts are table|col=?,col2=val
|
||||
func (c *fakeConn) prepareInsert(stmt *fakeStmt, parts []string) (dbimpl.Stmt, error) {
|
||||
if len(parts) != 2 {
|
||||
return nil, errf("invalid INSERT syntax with %d parts; want 2", len(parts))
|
||||
}
|
||||
stmt.table = parts[0]
|
||||
for n, colspec := range strings.Split(parts[1], ",") {
|
||||
nameVal := strings.Split(colspec, "=")
|
||||
if len(nameVal) != 2 {
|
||||
return nil, errf("INSERT table %q has invalid column spec of %q (index %d)", stmt.table, colspec, n)
|
||||
}
|
||||
column, value := nameVal[0], nameVal[1]
|
||||
ctype, ok := c.db.columnType(stmt.table, column)
|
||||
if !ok {
|
||||
return nil, errf("INSERT table %q references non-existent column %q", stmt.table, column)
|
||||
}
|
||||
stmt.colName = append(stmt.colName, column)
|
||||
|
||||
if value != "?" {
|
||||
var subsetVal interface{}
|
||||
// Convert to dbimpl subset type
|
||||
switch ctype {
|
||||
case "string":
|
||||
subsetVal = []byte(value)
|
||||
case "int32":
|
||||
i, err := strconv.Atoi(value)
|
||||
if err != nil {
|
||||
return nil, errf("invalid conversion to int32 from %q", value)
|
||||
}
|
||||
subsetVal = int64(i) // int64 is a subset type, but not int32
|
||||
default:
|
||||
return nil, errf("unsupported conversion for pre-bound parameter %q to type %q", value, ctype)
|
||||
}
|
||||
stmt.colValue = append(stmt.colValue, subsetVal)
|
||||
} else {
|
||||
stmt.placeholders++
|
||||
stmt.placeholderConverter = append(stmt.placeholderConverter, converterForType(ctype))
|
||||
stmt.colValue = append(stmt.colValue, "?")
|
||||
}
|
||||
}
|
||||
return stmt, nil
|
||||
}
|
||||
|
||||
func (c *fakeConn) Prepare(query string) (dbimpl.Stmt, error) {
|
||||
if c.db == nil {
|
||||
panic("nil c.db; conn = " + fmt.Sprintf("%#v", c))
|
||||
}
|
||||
parts := strings.Split(query, "|")
|
||||
if len(parts) < 1 {
|
||||
return nil, errf("empty query")
|
||||
}
|
||||
cmd := parts[0]
|
||||
parts = parts[1:]
|
||||
stmt := &fakeStmt{q: query, c: c, cmd: cmd}
|
||||
switch cmd {
|
||||
case "WIPE":
|
||||
// Nothing
|
||||
case "SELECT":
|
||||
return c.prepareSelect(stmt, parts)
|
||||
case "CREATE":
|
||||
return c.prepareCreate(stmt, parts)
|
||||
case "INSERT":
|
||||
return c.prepareInsert(stmt, parts)
|
||||
default:
|
||||
return nil, errf("unsupported command type %q", cmd)
|
||||
}
|
||||
return stmt, nil
|
||||
}
|
||||
|
||||
func (s *fakeStmt) ColumnCoverter(idx int) dbimpl.ValueConverter {
|
||||
return s.placeholderConverter[idx]
|
||||
}
|
||||
|
||||
func (s *fakeStmt) Close() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func (s *fakeStmt) Exec(args []interface{}) (dbimpl.Result, error) {
|
||||
db := s.c.db
|
||||
switch s.cmd {
|
||||
case "WIPE":
|
||||
db.wipe()
|
||||
return dbimpl.DDLSuccess, nil
|
||||
case "CREATE":
|
||||
if err := db.createTable(s.table, s.colName, s.colType); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return dbimpl.DDLSuccess, nil
|
||||
case "INSERT":
|
||||
return s.execInsert(args)
|
||||
}
|
||||
fmt.Printf("EXEC statement, cmd=%q: %#v\n", s.cmd, s)
|
||||
return nil, fmt.Errorf("unimplemented statement Exec command type of %q", s.cmd)
|
||||
}
|
||||
|
||||
func (s *fakeStmt) execInsert(args []interface{}) (dbimpl.Result, error) {
|
||||
db := s.c.db
|
||||
if len(args) != s.placeholders {
|
||||
panic("error in pkg db; should only get here if size is correct")
|
||||
}
|
||||
db.mu.Lock()
|
||||
t, ok := db.table(s.table)
|
||||
db.mu.Unlock()
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
|
||||
}
|
||||
|
||||
t.mu.Lock()
|
||||
defer t.mu.Unlock()
|
||||
|
||||
cols := make([]interface{}, len(t.colname))
|
||||
argPos := 0
|
||||
for n, colname := range s.colName {
|
||||
colidx := t.columnIndex(colname)
|
||||
if colidx == -1 {
|
||||
return nil, fmt.Errorf("fakedb: column %q doesn't exist or dropped since prepared statement was created", colname)
|
||||
}
|
||||
var val interface{}
|
||||
if strvalue, ok := s.colValue[n].(string); ok && strvalue == "?" {
|
||||
val = args[argPos]
|
||||
argPos++
|
||||
} else {
|
||||
val = s.colValue[n]
|
||||
}
|
||||
cols[colidx] = val
|
||||
}
|
||||
|
||||
t.rows = append(t.rows, &row{cols: cols})
|
||||
return dbimpl.RowsAffected(1), nil
|
||||
}
|
||||
|
||||
func (s *fakeStmt) Query(args []interface{}) (dbimpl.Rows, error) {
|
||||
db := s.c.db
|
||||
if len(args) != s.placeholders {
|
||||
panic("error in pkg db; should only get here if size is correct")
|
||||
}
|
||||
|
||||
db.mu.Lock()
|
||||
t, ok := db.table(s.table)
|
||||
db.mu.Unlock()
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("fakedb: table %q doesn't exist", s.table)
|
||||
}
|
||||
t.mu.Lock()
|
||||
defer t.mu.Unlock()
|
||||
|
||||
colIdx := make(map[string]int) // select column name -> column index in table
|
||||
for _, name := range s.colName {
|
||||
idx := t.columnIndex(name)
|
||||
if idx == -1 {
|
||||
return nil, fmt.Errorf("fakedb: unknown column name %q", name)
|
||||
}
|
||||
colIdx[name] = idx
|
||||
}
|
||||
|
||||
mrows := []*row{}
|
||||
rows:
|
||||
for _, trow := range t.rows {
|
||||
// Process the where clause, skipping non-match rows. This is lazy
|
||||
// and just uses fmt.Sprintf("%v") to test equality. Good enough
|
||||
// for test code.
|
||||
for widx, wcol := range s.whereCol {
|
||||
idx := t.columnIndex(wcol)
|
||||
if idx == -1 {
|
||||
return nil, fmt.Errorf("db: invalid where clause column %q", wcol)
|
||||
}
|
||||
tcol := trow.cols[idx]
|
||||
if bs, ok := tcol.([]byte); ok {
|
||||
// lazy hack to avoid sprintf %v on a []byte
|
||||
tcol = string(bs)
|
||||
}
|
||||
if fmt.Sprintf("%v", tcol) != fmt.Sprintf("%v", args[widx]) {
|
||||
continue rows
|
||||
}
|
||||
}
|
||||
mrow := &row{cols: make([]interface{}, len(s.colName))}
|
||||
for seli, name := range s.colName {
|
||||
mrow.cols[seli] = trow.cols[colIdx[name]]
|
||||
}
|
||||
mrows = append(mrows, mrow)
|
||||
}
|
||||
|
||||
cursor := &rowsCursor{
|
||||
pos: -1,
|
||||
rows: mrows,
|
||||
cols: s.colName,
|
||||
}
|
||||
return cursor, nil
|
||||
}
|
||||
|
||||
func (s *fakeStmt) NumInput() int {
|
||||
return s.placeholders
|
||||
}
|
||||
|
||||
func (tx *fakeTx) Commit() error {
|
||||
tx.c.currTx = nil
|
||||
return nil
|
||||
}
|
||||
|
||||
func (tx *fakeTx) Rollback() error {
|
||||
tx.c.currTx = nil
|
||||
return nil
|
||||
}
|
||||
|
||||
type rowsCursor struct {
|
||||
cols []string
|
||||
pos int
|
||||
rows []*row
|
||||
closed bool
|
||||
}
|
||||
|
||||
func (rc *rowsCursor) Close() error {
|
||||
rc.closed = true
|
||||
return nil
|
||||
}
|
||||
|
||||
func (rc *rowsCursor) Columns() []string {
|
||||
return rc.cols
|
||||
}
|
||||
|
||||
func (rc *rowsCursor) Next(dest []interface{}) error {
|
||||
if rc.closed {
|
||||
return errors.New("fakedb: cursor is closed")
|
||||
}
|
||||
rc.pos++
|
||||
if rc.pos >= len(rc.rows) {
|
||||
return io.EOF // per interface spec
|
||||
}
|
||||
for i, v := range rc.rows[rc.pos].cols {
|
||||
// TODO(bradfitz): convert to subset types? naah, I
|
||||
// think the subset types should only be input to
|
||||
// dbimpl, but the db package should be able to handle
|
||||
// a wider range of types coming out of dbimpl
|
||||
// drivers. all for ease of drivers, and to prevent
|
||||
// drivers from messing up conversions or doing them
|
||||
// differently.
|
||||
dest[i] = v
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func converterForType(typ string) dbimpl.ValueConverter {
|
||||
switch typ {
|
||||
case "bool":
|
||||
return dbimpl.Bool
|
||||
case "int32":
|
||||
return dbimpl.Int32
|
||||
case "string":
|
||||
return dbimpl.String
|
||||
}
|
||||
panic("invalid fakedb column type of " + typ)
|
||||
}
|
||||
Loading…
Reference in New Issue