Add a package listing API to cipd.

go/src/infra/tools/cipd/apps/cipd/main.go

Index: go/src/infra/tools/cipd/apps/cipd/main.go
diff --git a/go/src/infra/tools/cipd/apps/cipd/main.go b/go/src/infra/tools/cipd/apps/cipd/main.go
index 132b83d606e49dd2d785ff0e64b551fa8e99672d..f433ef7c717d7ab6714f9d564072b42cb9fda77c 100644
--- a/go/src/infra/tools/cipd/apps/cipd/main.go
+++ b/go/src/infra/tools/cipd/apps/cipd/main.go
@@ -41,14 +41,16 @@ var (
 
 // checkCommandLine ensures all required positional and flag-like parameters
 // are set. Returns true if they are, or false (and prints to stderr) if not.
-func checkCommandLine(args []string, flags *flag.FlagSet, positionalCount int) bool {
+func checkCommandLine(args []string, flags *flag.FlagSet, minPositionalCount int,
+	maxPositionalCount int) bool {

[Vadim Sh., 2015/06/23 00:08:35]

nit: we don't limit go code to 80 chars. In this case I think it'll be better to
keep it on the same line (and deduplicating 'int'):

func ... minPositionalCount, maxPositionalCount int)

also replacing 'positional' with just 'pos' is also ok (e.g. minPosCount,
maxPosCount). 

[estaab, 2015/06/23 02:26:13]

Done.

 	// Check number of expected positional arguments.
-	if positionalCount == 0 && len(args) != 0 {
+	if maxPositionalCount == 0 && len(args) != 0 {
 		log.Errorf("Unexpected arguments: %v", args)
 		return false
 	}
-	if len(args) != positionalCount {
-		log.Errorf("Expecting %d arguments, got %d", positionalCount, len(args))
+	if len(args) < minPositionalCount || len(args) > maxPositionalCount {
+		log.Errorf("Expecting [%d, %d] arguments, got %d", minPositionalCount,
+			maxPositionalCount, len(args))
 		return false
 	}
 	// Check required unset flags.
@@ -314,6 +316,18 @@ func (opts *JSONOutputOptions) writeJSONOutput(result interface{}, err error) er
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// ListPackagesOptions mixin.

[Vadim Sh., 2015/06/23 00:08:35]

no need for separate struct if it's not going to be reused by multiple
subcommands.

[estaab, 2015/06/23 02:26:13]

Done.

+
+// ListPackagesOptions defines a recursive option to list packages in subdirectories.
+type ListPackagesOptions struct {
+	recursive bool
+}
+
+func (opts *ListPackagesOptions) registerFlags(f *flag.FlagSet) {
+	f.BoolVar(&opts.recursive, "r", false, "Whether to list packages in subdirectories.")
+}
+
+////////////////////////////////////////////////////////////////////////////////
 // 'create' subcommand.
 
 var cmdCreate = &subcommands.Command{
@@ -339,7 +353,7 @@ type createRun struct {
 }
 
 func (c *createRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 0) {
+	if !checkCommandLine(args, c.GetFlags(), 0, 0) {
 		return 1
 	}
 	pin, err := buildAndUploadInstance(c.InputOptions, c.TagsOptions, c.ServiceOptions)
@@ -392,7 +406,7 @@ type ensureRun struct {
 }
 
 func (c *ensureRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 0) {
+	if !checkCommandLine(args, c.GetFlags(), 0, 0) {
 		return 1
 	}
 	err := ensurePackages(c.rootDir, c.listFile, c.ServiceOptions)
@@ -447,7 +461,7 @@ type resolveRun struct {
 }
 
 func (c *resolveRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 0) {
+	if !checkCommandLine(args, c.GetFlags(), 0, 0) {
 		return 1
 	}
 	pin, err := resolveVersion(c.packageName, c.version, c.ServiceOptions)
@@ -469,6 +483,62 @@ func resolveVersion(packageName, version string, serviceOpts ServiceOptions) (co
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// 'ls' subcommand.
+
+var cmdListPackages = &subcommands.Command{
+	UsageLine: "ls [-r] [<prefix string>]",
+	ShortDesc: "List matching packages.",
+	LongDesc:  "List packages in the given path to which the user has access, optionally recursively",
+	CommandRun: func() subcommands.CommandRun {
+		c := &listPackagesRun{}
+		c.ListPackagesOptions.registerFlags(&c.Flags)
+		c.ServiceOptions.registerFlags(&c.Flags)
+		return c
+	},
+}
+
+type listPackagesRun struct {
+	subcommands.CommandRunBase
+	ListPackagesOptions
+	ServiceOptions
+}
+
+func (c *listPackagesRun) Run(a subcommands.Application, args []string) int {
+	if !checkCommandLine(args, c.GetFlags(), 0, 1) {
+		return 1
+	}
+	path := ""
+	if len(args) == 1 {
+		path = args[0]
+	}
+	err := listPackages(path, c.ListPackagesOptions, c.ServiceOptions)
+	if err != nil {
+		log.Errorf("Error while listing packages: %s", err)
+		return 1
+	}
+	return 0
+}
+
+func listPackages(path string, listOpts ListPackagesOptions, serviceOpts ServiceOptions) error {
+	client, err := serviceOpts.makeCipdClient("")
+	if err != nil {
+		return err
+	}
+	packages, err := client.ListPackages(path, listOpts.recursive)
+	if err != nil {
+		return err
+	}
+	if len(packages) == 0 {
+		log.Infof("No matching packages.")
+	} else {
+		for _, p := range packages {
+			log.Infof("%s", p)
+		}
+	}
+	return nil
+}
+
+////////////////////////////////////////////////////////////////////////////////
 // 'acl-list' subcommand.
 
 var cmdListACL = &subcommands.Command{
@@ -488,7 +558,7 @@ type listACLRun struct {
 }
 
 func (c *listACLRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 1) {
+	if !checkCommandLine(args, c.GetFlags(), 1, 1) {
 		return 1
 	}
 	err := listACL(args[0], c.ServiceOptions)
@@ -584,7 +654,7 @@ type editACLRun struct {
 }
 
 func (c *editACLRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 1) {
+	if !checkCommandLine(args, c.GetFlags(), 1, 1) {
 		return 1
 	}
 	err := editACL(args[0], c.owner, c.writer, c.reader, c.revoke, c.ServiceOptions)
@@ -657,7 +727,7 @@ type buildRun struct {
 }
 
 func (c *buildRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 0) {
+	if !checkCommandLine(args, c.GetFlags(), 0, 0) {
 		return 1
 	}
 	err := buildInstanceFile(c.outputFile, c.InputOptions)
@@ -720,7 +790,7 @@ type deployRun struct {
 }
 
 func (c *deployRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 1) {
+	if !checkCommandLine(args, c.GetFlags(), 1, 1) {
 		return 1
 	}
 	err := deployInstanceFile(c.rootDir, args[0])
@@ -769,7 +839,7 @@ type fetchRun struct {
 }
 
 func (c *fetchRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 0) {
+	if !checkCommandLine(args, c.GetFlags(), 0, 0) {
 		return 1
 	}
 	err := fetchInstanceFile(c.packageName, c.version, c.outputPath, c.ServiceOptions)
@@ -840,7 +910,7 @@ type inspectRun struct {
 }
 
 func (c *inspectRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 1) {
+	if !checkCommandLine(args, c.GetFlags(), 1, 1) {
 		return 1
 	}
 	pin, err := inspectInstanceFile(args[0], true)
@@ -905,7 +975,7 @@ type registerRun struct {
 }
 
 func (c *registerRun) Run(a subcommands.Application, args []string) int {
-	if !checkCommandLine(args, c.GetFlags(), 1) {
+	if !checkCommandLine(args, c.GetFlags(), 1, 1) {
 		return 1
 	}
 	pin, err := registerInstanceFile(args[0], c.TagsOptions, c.ServiceOptions)
@@ -949,6 +1019,7 @@ var application = &subcommands.DefaultApplication{
 		subcommands.CmdHelp,
 
 		// High level commands.
+		cmdListPackages,
 		cmdCreate,
 		cmdEnsure,
 		cmdResolve,