From 1026c32f06347fe96f535f4c40dec660aaa4663d Mon Sep 17 00:00:00 2001 From: Brad Fitzpatrick Date: Mon, 5 Mar 2012 07:34:01 -0800 Subject: [PATCH] remove the db and dbimpl packages; now in the Go core as database/sql and database/sql/driver Change-Id: Ie88df6466f9b81e4320895049dd3611c43e0ea4a --- pkg/db/convert.go | 118 --------- pkg/db/convert_test.go | 120 --------- pkg/db/db.go | 541 ---------------------------------------- pkg/db/db_test.go | 154 ------------ pkg/db/dbimpl/dbimpl.go | 131 ---------- pkg/db/dbimpl/types.go | 105 -------- pkg/db/doc.txt | 46 ---- pkg/db/fakedb_test.go | 511 ------------------------------------- 8 files changed, 1726 deletions(-) delete mode 100644 pkg/db/convert.go delete mode 100644 pkg/db/convert_test.go delete mode 100644 pkg/db/db.go delete mode 100644 pkg/db/db_test.go delete mode 100644 pkg/db/dbimpl/dbimpl.go delete mode 100644 pkg/db/dbimpl/types.go delete mode 100644 pkg/db/doc.txt delete mode 100644 pkg/db/fakedb_test.go diff --git a/pkg/db/convert.go b/pkg/db/convert.go deleted file mode 100644 index e12a82d36..000000000 --- a/pkg/db/convert.go +++ /dev/null @@ -1,118 +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. -*/ - -// Type conversions for Scan. - -package db - -import ( - "errors" - "fmt" - "reflect" - "strconv" -) - -// copyConvert copies to dest the value in src, converting it if possible -// An error is returned if the copy would result in loss of information. -// dest should be a pointer type. -func copyConvert(dest, src interface{}) error { - // Common cases, without reflect. Fall through. - switch s := src.(type) { - case string: - switch d := dest.(type) { - case *string: - *d = s - return nil - } - case []byte: - switch d := dest.(type) { - case *string: - *d = string(s) - return nil - case *[]byte: - *d = s - return nil - } - } - - sv := reflect.ValueOf(src) - - switch d := dest.(type) { - case *string: - switch sv.Kind() { - case reflect.Bool, - reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, - reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, - reflect.Float32, reflect.Float64: - *d = fmt.Sprintf("%v", src) - return nil - } - } - - if scanner, ok := dest.(ScannerInto); ok { - return scanner.ScanInto(src) - } - - dpv := reflect.ValueOf(dest) - if dpv.Kind() != reflect.Ptr { - return errors.New("destination not a pointer") - } - - dv := reflect.Indirect(dpv) - if dv.Kind() == sv.Kind() { - dv.Set(sv) - return nil - } - - switch dv.Kind() { - case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: - if s, ok := asString(src); ok { - i64, err := strconv.ParseInt(s, 10, 64) - if err != nil { - return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err) - } - if dv.OverflowInt(i64) { - return fmt.Errorf("string %q overflows %s", s, dv.Kind()) - } - dv.SetInt(i64) - return nil - } - case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64: - if s, ok := asString(src); ok { - u64, err := strconv.ParseUint(s, 10, 64) - if err != nil { - return fmt.Errorf("converting string %q to a %s: %v", s, dv.Kind(), err) - } - if dv.OverflowUint(u64) { - return fmt.Errorf("string %q overflows %s", s, dv.Kind()) - } - dv.SetUint(u64) - return nil - } - } - - return fmt.Errorf("unsupported driver -> Scan pair: %T -> %T", src, dest) -} - -func asString(src interface{}) (s string, ok bool) { - switch v := src.(type) { - case string: - return v, true - case []byte: - return string(v), true - } - return "", false -} diff --git a/pkg/db/convert_test.go b/pkg/db/convert_test.go deleted file mode 100644 index 9ba6bd238..000000000 --- a/pkg/db/convert_test.go +++ /dev/null @@ -1,120 +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 ( - "fmt" - "reflect" - "testing" -) - -type conversionTest struct { - s, d interface{} // source and destination - - // following are used if they're non-zero - wantint int64 - wantuint uint64 - wantstr string - wanterr string -} - -// Target variables for scanning into. -var ( - scanstr string - scanint int - scanint8 int8 - scanint16 int16 - scanint32 int32 - scanuint8 uint8 - scanuint16 uint16 -) - -var conversionTests = []conversionTest{ - // Exact conversions (destination pointer type matches source type) - {s: "foo", d: &scanstr, wantstr: "foo"}, - {s: 123, d: &scanint, wantint: 123}, - - // To strings - {s: []byte("byteslice"), d: &scanstr, wantstr: "byteslice"}, - {s: 123, d: &scanstr, wantstr: "123"}, - {s: int8(123), d: &scanstr, wantstr: "123"}, - {s: int64(123), d: &scanstr, wantstr: "123"}, - {s: uint8(123), d: &scanstr, wantstr: "123"}, - {s: uint16(123), d: &scanstr, wantstr: "123"}, - {s: uint32(123), d: &scanstr, wantstr: "123"}, - {s: uint64(123), d: &scanstr, wantstr: "123"}, - {s: 1.5, d: &scanstr, wantstr: "1.5"}, - - // Strings to integers - {s: "255", d: &scanuint8, wantuint: 255}, - {s: "256", d: &scanuint8, wanterr: `string "256" overflows uint8`}, - {s: "256", d: &scanuint16, wantuint: 256}, - {s: "-1", d: &scanint, wantint: -1}, - {s: "foo", d: &scanint, wanterr: `converting string "foo" to a int: parsing "foo": invalid argument`}, -} - -func intValue(intptr interface{}) int64 { - return reflect.Indirect(reflect.ValueOf(intptr)).Int() -} - -func uintValue(intptr interface{}) uint64 { - return reflect.Indirect(reflect.ValueOf(intptr)).Uint() -} - -func TestConversions(t *testing.T) { - for n, ct := range conversionTests { - err := copyConvert(ct.d, ct.s) - errstr := "" - if err != nil { - errstr = err.String() - } - errf := func(format string, args ...interface{}) { - base := fmt.Sprintf("copyConvert #%d: for %v (%T) -> %T, ", n, ct.s, ct.s, ct.d) - t.Errorf(base+format, args...) - } - if errstr != ct.wanterr { - errf("got error %q, want error %q", errstr, ct.wanterr) - } - if ct.wantstr != "" && ct.wantstr != scanstr { - errf("want string %q, got %q", ct.wantstr, scanstr) - } - if ct.wantint != 0 && ct.wantint != intValue(ct.d) { - errf("want int %d, got %d", ct.wantint, intValue(ct.d)) - } - if ct.wantuint != 0 && ct.wantuint != uintValue(ct.d) { - errf("want uint %d, got %d", ct.wantuint, uintValue(ct.d)) - } - } -} - -func TestNullableString(t *testing.T) { - var ns NullableString - copyConvert(&ns, []byte("foo")) - if !ns.Ok { - t.Errorf("expecting ok") - } - if ns.String != "foo" { - t.Errorf("expecting foo; got %q", ns.String) - } - copyConvert(&ns, nil) - if ns.Ok { - t.Errorf("expecting not ok on nil") - } - if ns.String != "" { - t.Errorf("expecting blank on nil; got %q", ns.String) - } -} diff --git a/pkg/db/db.go b/pkg/db/db.go deleted file mode 100644 index e8600dd5b..000000000 --- a/pkg/db/db.go +++ /dev/null @@ -1,541 +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 provides a generic interface around SQL (or SQL-like) -// databases. -package db - -import ( - "errors" - "fmt" - "io" - "runtime" - "sync" - - "camlistore.org/pkg/db/dbimpl" -) - -var drivers = make(map[string]dbimpl.Driver) - -// Register makes a database driver available by the provided name. -// It's a fatal error to register the same or different drivers with -// a duplicate name. -func Register(name string, driver dbimpl.Driver) { - if driver == nil { - panic("db: Register driver is nil") - } - if _, dup := drivers[name]; dup { - panic("db: Register called twice for driver " + name) - } - drivers[name] = driver -} - -// NullableString is type representing a string which may be -// null. NullableString implements the ScannerInto inteface so can be -// used as a scan destination: -// -// var s NullableString -// err := db.QueryRow("SELECT name FROM foo WHERE id=?", id).Scan(&s) -// ... -// if !s.Ok { -// // NULL value -// } else { -// // use s.String -// } -// -// TODO(bradfitz): add other types. -type NullableString struct { - String string - Ok bool // Ok is true if the String is not NULL -} - -// ScanInto implements the ScannerInto interface. -func (ms *NullableString) ScanInto(value interface{}) error { - if value == nil { - ms.String, ms.Ok = "", false - return nil - } - ms.Ok = true - return copyConvert(&ms.String, value) -} - -// ScannerInto is an interface used by Scan. -type ScannerInto interface { - // value is nil for NULL database columns. - ScanInto(value interface{}) error -} - -// ErrNoRows is returned by Scan when QueryRow doesn't return a -// row. In such a case, QueryRow returns a placeholder *Row value that -// defers this error until a Scan. -var ErrNoRows = errors.New("db: no rows in result set") - -// DB is a database handle. It's safe for concurrent use by multiple -// goroutines. -type DB struct { - driver dbimpl.Driver - dsn string - - mu sync.Mutex - freeConn []dbimpl.Conn -} - -// Open opens a database specified by its database driver name and a -// driver-specific data source name, usually consisting of at least a -// database name and connection information. -// -// Most users will open a database via a driver-specific connection -// helper function that returns a *DB. -func Open(driverName, dataSourceName string) (*DB, error) { - driver, ok := drivers[driverName] - if !ok { - return nil, fmt.Errorf("db: unknown driver %q (forgotten import?)", driverName) - } - return &DB{driver: driver, dsn: dataSourceName}, nil -} - -func (db *DB) maxIdleConns() int { - const defaultMaxIdleConns = 2 - // TODO(bradfitz): ask driver, if supported, for its default preference - // TODO(bradfitz): let users override? - return defaultMaxIdleConns -} - -// conn returns a newly-opened or cached dbimpl.Conn -func (db *DB) conn() (dbimpl.Conn, error) { - db.mu.Lock() - if n := len(db.freeConn); n > 0 { - conn := db.freeConn[n-1] - db.freeConn = db.freeConn[:n-1] - db.mu.Unlock() - return conn, nil - } - db.mu.Unlock() - return db.driver.Open(db.dsn) -} - -func (db *DB) connIfFree(wanted dbimpl.Conn) (conn dbimpl.Conn, ok bool) { - db.mu.Lock() - defer db.mu.Unlock() - for n, conn := range db.freeConn { - if conn == wanted { - db.freeConn[n] = db.freeConn[len(db.freeConn)-1] - db.freeConn = db.freeConn[:len(db.freeConn)-1] - return wanted, true - } - } - return nil, false -} - -func (db *DB) putConn(c dbimpl.Conn) { - if n := len(db.freeConn); n < db.maxIdleConns() { - db.freeConn = append(db.freeConn, c) - return - } - db.closeConn(c) -} - -func (db *DB) closeConn(c dbimpl.Conn) { - // TODO: check to see if we need this Conn for any prepared statements - // that are active. - c.Close() -} - -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 -} diff --git a/pkg/db/db_test.go b/pkg/db/db_test.go deleted file mode 100644 index a4e885f1e..000000000 --- a/pkg/db/db_test.go +++ /dev/null @@ -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) - } - } -} diff --git a/pkg/db/dbimpl/dbimpl.go b/pkg/db/dbimpl/dbimpl.go deleted file mode 100644 index ec528aba9..000000000 --- a/pkg/db/dbimpl/dbimpl.go +++ /dev/null @@ -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") -} diff --git a/pkg/db/dbimpl/types.go b/pkg/db/dbimpl/types.go deleted file mode 100644 index 4c8e60ecc..000000000 --- a/pkg/db/dbimpl/types.go +++ /dev/null @@ -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()) -} diff --git a/pkg/db/doc.txt b/pkg/db/doc.txt deleted file mode 100644 index dbd0df978..000000000 --- a/pkg/db/doc.txt +++ /dev/null @@ -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. diff --git a/pkg/db/fakedb_test.go b/pkg/db/fakedb_test.go deleted file mode 100644 index ea6e722a2..000000000 --- a/pkg/db/fakedb_test.go +++ /dev/null @@ -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||=,=,... -// where types are: "string", [u]int{8,16,32,64}, "bool" -// INSERT||col=val,col2=val2,col3=? -// SELECT||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: -// -// ;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) -}