Improve templating

README.md

@@ -18,24 +18,25 @@ Running
 -------
 
 ```
-$ retrodep -h
 retrodep: help requested
 usage: retrodep [OPTION]... PATH
   -debug
-        show debugging output
+    	show debugging output
   -deps
-        show vendored dependencies (default true)
-  -exclude-from string
-        ignore glob patterns listed in provided file
+    	show vendored dependencies (default true)
+  -exclude-from exclusions
+    	ignore directory entries matching globs in exclusions
   -help
-        print help
+    	print help
   -importpath string
-        top-level import path
+    	top-level import path
+  -o string
+    	output format, one of: go-template=...
   -only-importpath
-        only show the top-level import path
+    	only show the top-level import path
   -template string
-        go template to use for output with Repo, Rev, Tag and Ver
-  -x    exit on the first failure
+    	go template to use for output with Reference fields (deprecated)
+  -x	exit on the first failure
 ```
 
 In many cases retrodep can work out the import path for the top-level project. In those cases, simply supply the directory name to examine:
@@ -68,24 +69,25 @@ Example output
 --------------
 
 ```
-$ retrodep -importpath github.com/docker/distribution go/src/github.com/docker/distribution
-*github.com/docker/distribution@90705d2fb81dda1466be49bd958ed8a0dd9a6145 ~v2.6.0rc.1-1.20180831002537-90705d2fb81d
-github.com/opencontainers/image-spec@87998cd070d9e7a2c79f8b153a26bea0425582e5 =v1.0.0 ~v1.0.0
-github.com/ncw/swift@b964f2ca856aac39885e258ad25aec08d5f64ee6 ~v1.0.25-0.20160617142549-b964f2ca856a
-golang.org/x/oauth2@2897dcade18a126645f1368de827f1e613a60049 ~v0.0.0-0.20160323192119-2897dcade18a
-rsc.io/letsencrypt ?
+$ retrodep $GOPATH/src/github.com/docker/distribution
+github.com/docker/distribution:v2.7.1
+github.com/docker/distribution:v2.7.1/github.com/Azure/azure-sdk-for-go:v16.2.1
+github.com/docker/distribution:v2.7.1/github.com/Azure/go-autorest:v10.8.1
+github.com/docker/distribution:v2.7.1/github.com/Shopify/logrus-bugsnag:v0.0.0-0.20171204154709-577dee27f20d
+github.com/docker/distribution:v2.7.1/github.com/aws/aws-sdk-go:v1.15.11
+github.com/docker/distribution:v2.7.1/github.com/beorn7/perks:v0.0.0-0.20160804124726-4c0e84591b9a
+github.com/docker/distribution:v2.7.1/github.com/bshuster-repo/logrus-logstash-hook:0.4
+github.com/docker/distribution:v2.7.1/github.com/bugsnag/bugsnag-go:v1.0.3-0.20150204195350-f36a9b3a9e01
 ...
 ```
 
 In this example,
 
-* github.com/docker/distribution is the top-level repository (indicated by \*)
-* github.com/opencontainers/image-spec had a matching semantic version tag (v1.0.0)
-* github.com/ncw/swift's matching commit had semantic version tag v1.0.24 reachable (so the next patch version would be v1.0.25)
-* golang.org/x/oauth2 had a matching commit but no reachable semantic version tag
-* rsc.io/letsencrypt had no matching commit (because the vendored source was from a fork)
-* for github.com/docker/distribution, tag v2.6.0rc.1 was reachable from the matching commit (note, 1.timestamp instead of 0.timestamp)
-
+* github.com/docker/distribution is the top-level package, and the upstream semantic version tag v2.7.1 matches
+* github.com/Azure/azure-sdk-for-go etc are vendored dependencies of distribution
+* github.com/Azure/azure-sdk-for-go, github.com/Azure/go-autorest, github.com/aws/awk-sdk-go, and github.com/bshuster-repo/logrus-logstash-hook all had matches with upstream semantic version tags
+* github.com/bugsnag/bugsnag-go matched a commit from which tag v1.0.2 was reachable (note: v1.0.2, not v1.0.3 -- see below)
+* github.com/beorn7/perks matched a commit from which there were no reachable semantic version tags
 
 Pseudo-versions
 ---------------

main.go

@@ -24,11 +24,14 @@ import (
 	"path/filepath"
 	"sort"
 	"strings"
+	"text/template"
 
 	"github.com/op/go-logging"
 	"github.com/release-engineering/retrodep/retrodep"
 )
 
+const defaultTemplate string = "{{if .TopPkg}}{{.TopPkg}}:{{.TopVer}}/{{end}}{{.Pkg}}:{{.Ver}}"
+
 var log = logging.MustGetLogger("retrodep")
 
 var helpFlag = flag.Bool("help", false, "print help")
@@ -37,10 +40,12 @@ var onlyImportPath = flag.Bool("only-importpath", false, "only show the top-leve
 var depsFlag = flag.Bool("deps", true, "show vendored dependencies")
 var excludeFrom = flag.String("exclude-from", "", "ignore directory entries matching globs in `exclusions`")
 var debugFlag = flag.Bool("debug", false, "show debugging output")
-var template = flag.String("template", "", "go template to use for output with Repo, Rev, Tag and Ver")
+var outputArg = flag.String("o", "", "output format, one of: go-template=...")
+var templateArg = flag.String("template", "", "go template to use for output with Pkg, Repo, Rev, Tag and Ver (deprecated)")
 var exitFirst = flag.Bool("x", false, "exit on the first failure")
 
 var errorShown = false
+var usage func(string)
 
 func displayUnknown(name string) {
 	fmt.Printf("%s ?\n", name)
@@ -53,14 +58,10 @@ func displayUnknown(name string) {
 	}
 }
 
-func display(template string, name string, ref *retrodep.Reference) {
+func display(tmpl *template.Template, name string, ref *retrodep.Reference) {
 	var builder strings.Builder
 	builder.WriteString(name)
-	var tmpl, err = retrodep.Display(template)
-	if err != nil {
-		log.Fatalf("Error parsing supplied template. %s ", err)
-	}
-	err = tmpl.Execute(&builder, ref)
+	err := tmpl.Execute(&builder, ref)
 	if err != nil {
 		log.Fatalf("Error generating output. %s ", err)
 	}
@@ -82,20 +83,30 @@ func getProject(src *retrodep.GoSource, importPath string) *retrodep.RepoPath {
 	return main
 }
 
-func showTopLevel(src *retrodep.GoSource) {
+func showTopLevel(tmpl *template.Template, src *retrodep.GoSource) *retrodep.Reference {
 	main := getProject(src, *importPath)
-	project, err := src.DescribeProject(main, src.Path)
+	project, err := src.DescribeProject(main, src.Path, nil)
+	var topLevelMarker string
+	if *templateArg != "" {
+		topLevelMarker = "*"
+	}
 	switch err {
 	case retrodep.ErrorVersionNotFound:
-		displayUnknown("*" + main.Root)
+		displayUnknown(topLevelMarker + main.Root)
 	case nil:
-		display(*template, "*"+main.Root, project)
+		display(tmpl, topLevelMarker, project)
 	default:
 		log.Fatalf("%s: %s", src.Path, err)
 	}
+
+	if err != nil {
+		return nil
+	}
+
+	return project
 }
 
-func showVendored(src *retrodep.GoSource) {
+func showVendored(tmpl *template.Template, src *retrodep.GoSource, top *retrodep.Reference) {
 	vendored, err := src.VendoredProjects()
 	if err != nil {
 		log.Fatal(err)
@@ -111,12 +122,12 @@ func showVendored(src *retrodep.GoSource) {
 	// Describe each vendored project
 	for _, repo := range repos {
 		project := vendored[repo]
-		vp, err := src.DescribeVendoredProject(project)
+		vp, err := src.DescribeVendoredProject(project, top)
 		switch err {
 		case retrodep.ErrorVersionNotFound:
 			displayUnknown(project.Root)
 		case nil:
-			display(*template, project.Root, vp)
+			display(tmpl, "", vp)
 		default:
 			log.Fatalf("%s: %s\n", project.Root, err)
 		}
@@ -153,7 +164,7 @@ func processArgs(args []string) []*retrodep.GoSource {
 	cli.Usage = func() {}
 
 	usageMsg := fmt.Sprintf("usage: %s [OPTION]... PATH", progName)
-	usage := func(flaw string) {
+	usage = func(flaw string) {
 		log.Fatalf("%s: %s\n%s\n", progName, flaw, usageMsg)
 	}
 	err := cli.Parse(args[1:])
@@ -198,14 +209,30 @@ func processArgs(args []string) []*retrodep.GoSource {
 func main() {
 	srcs := processArgs(os.Args)
 
+	var customTemplate string
+	switch {
+	case *outputArg != "":
+		customTemplate = strings.TrimPrefix(*outputArg, "go-template=")
+		if customTemplate == *outputArg {
+			usage("unknown output format")
+		}
+	case *templateArg != "":
+		customTemplate = "{{.Pkg}}" + *templateArg
+	default:
+		customTemplate = defaultTemplate
+	}
+	tmpl, err := template.New("output").Parse(customTemplate)
+	if err != nil {
+		log.Fatal(err)
+	}
 	for _, src := range srcs {
 		if *onlyImportPath {
 			main := getProject(src, *importPath)
 			fmt.Println("*" + main.Root)
 		} else {
-			showTopLevel(src)
+			top := showTopLevel(tmpl, src)
 			if *depsFlag {
-				showVendored(src)
+				showVendored(tmpl, src, top)
 			}
 		}
 	}