camtool: add describe command

Change-Id: I956c4a76f00bc96f2e5f2b1e5b19a1b656dd1585

cmd/camtool/describe.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2014 The Camlistore Authors.
+
+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 main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"time"
+
+	"camlistore.org/pkg/blob"
+	"camlistore.org/pkg/client"
+	"camlistore.org/pkg/cmdmain"
+	"camlistore.org/pkg/search"
+	"camlistore.org/pkg/types"
+)
+
+type desCmd struct {
+	src   string
+	depth int
+
+	logger *log.Logger
+}
+
+func init() {
+	cmdmain.RegisterCommand("describe", func(flags *flag.FlagSet) cmdmain.CommandRunner {
+		cmd := new(desCmd)
+		flags.StringVar(&cmd.src, "src", "", "Source blobserver is either a URL prefix (with optional path), a host[:port], a path (starting with /, ./, or ../), or blank to use the Camlistore client config's default host.")
+		flags.IntVar(&cmd.depth, "depth", 1, "Depth to follow in describe request")
+		return cmd
+	})
+}
+
+func (c *desCmd) Describe() string {
+	return "Ask the search system to describe one or more blobs."
+}
+
+func (c *desCmd) Usage() {
+	fmt.Fprintf(os.Stderr, "Usage: camtool [globalopts] describe [--depth=n] blobref [blobref, blobref...]\n")
+}
+
+func (c *desCmd) Examples() []string {
+	return []string{}
+}
+
+func (c *desCmd) RunCommand(args []string) error {
+	if len(args) == 0 {
+		return cmdmain.UsageError("requires blobref")
+	}
+	var blobs []blob.Ref
+	for _, arg := range args {
+		br, ok := blob.Parse(arg)
+		if !ok {
+			return cmdmain.UsageError(fmt.Sprintf("invalid blobref %q", arg))
+		}
+		blobs = append(blobs, br)
+	}
+	var at time.Time // TODO: implement. from "2 days ago" "-2d", "-2h", "2013-02-05", etc
+
+	cl := c.client()
+	res, err := cl.Describe(&search.DescribeRequest{
+		BlobRefs: blobs,
+		Depth:    c.depth,
+		At:       types.Time3339(at),
+	})
+	if err != nil {
+		return err
+	}
+	resj, err := json.MarshalIndent(res, "", "  ")
+	if err != nil {
+		return err
+	}
+	resj = append(resj, '\n')
+	_, err = os.Stdout.Write(resj)
+	return err
+}
+
+func (c *desCmd) client() *client.Client {
+	var cl *client.Client
+	if c.src == "" {
+		cl = client.NewOrFail()
+	} else {
+		cl = client.New(c.src)
+	}
+	cl.SetLogger(c.logger)
+	cl.SetHTTPClient(&http.Client{
+		Transport: cl.TransportForConfig(nil),
+	})
+	cl.SetupAuth()
+	return cl
+}