feat: add assets-config

Signed-off-by: Manfred Touron <94029+moul@users.noreply.github.com>

.github/assets-config.json

@@ -0,0 +1,36 @@
+{
+  "VersionAliases": {
+    "latest": {
+      "Assets": 18,
+      "TargetVersion": "v1.5.1"
+    },
+    "v1": {
+      "Assets": 18,
+      "TargetVersion": "v1.5.1"
+    },
+    "v1.0": {
+      "Assets": 18,
+      "TargetVersion": "v1.0.0"
+    },
+    "v1.1": {
+      "Assets": 18,
+      "TargetVersion": "v1.1.3"
+    },
+    "v1.2": {
+      "Assets": 18,
+      "TargetVersion": "v1.2.0"
+    },
+    "v1.3": {
+      "Assets": 18,
+      "TargetVersion": "v1.3.0"
+    },
+    "v1.4": {
+      "Assets": 18,
+      "TargetVersion": "v1.4.5"
+    },
+    "v1.5": {
+      "Assets": 18,
+      "TargetVersion": "v1.5.1"
+    }
+  }
+}

Makefile

@@ -20,6 +20,8 @@ generate: install
 	echo 'foo@bar:~$$ repoman info .' > .tmp/example-info.txt
 	repoman info . >> .tmp/example-info.txt
 
+	repoman assets-config . > .github/assets-config.json
+
 	embedmd -w README.md
 	rm -rf .tmp
 .PHONY: generate

README.md

@@ -26,9 +26,9 @@ foo@bar:~$ repoman info .
 {
   "Git": {
     "CloneURL": "git@github.com:moul/repoman",
-    "CurrentBranch": "master",
+    "CurrentBranch": "dev/moul/assets-config",
     "HTMLURL": "https://github.com/moul/repoman",
-    "InMainBranch": true,
+    "InMainBranch": false,
     "IsDirty": null,
     "MainBranch": "master",
     "Metadata": {
@@ -63,6 +63,7 @@ SUBCOMMANDS
   maintenance          perform various maintenance tasks (write)
   version              show version and build info
   template-post-clone  replace template
+  assets-config        generate a configuration for assets
 
 FLAGS
   -v false  verbose mode

assets-config.go

@@ -0,0 +1,131 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"sort"
+
+	"github.com/Masterminds/semver"
+	"github.com/google/go-github/v35/github"
+	"github.com/hokaccha/go-prettyjson"
+	"go.uber.org/multierr"
+	"go.uber.org/zap"
+	"golang.org/x/sync/errgroup"
+	"moul.io/u"
+)
+
+func doAssetsConfig(ctx context.Context, args []string) error {
+	if len(args) < 1 {
+		return flag.ErrHelp
+	}
+	paths := u.UniqueStrings(args)
+	logger.Debug("doAssetsConfig", zap.Any("opts", opts), zap.Strings("project", paths))
+
+	var errs error
+	g, ctx := errgroup.WithContext(ctx)
+	for _, path := range paths {
+		path := path
+		g.Go(func() error {
+			err := doAssetsConfigOnce(ctx, path)
+			if err != nil {
+				errs = multierr.Append(errs, fmt.Errorf("%q: %w", path, err))
+			}
+			return nil
+		})
+	}
+	_ = g.Wait()
+	return errs
+}
+
+type assetConfigVersion struct {
+	TargetVersion string `json:",omitempty"`
+	Assets        int    `json:",omitempty"`
+}
+
+type assetConfig struct {
+	VersionAliases map[string]assetConfigVersion
+	SemverMapping  map[string]string `json:",omitempty"`
+}
+
+func doAssetsConfigOnce(_ context.Context, path string) error {
+	project, err := projectFromPath(path)
+	if err != nil {
+		return fmt.Errorf("invalid project: %w", err)
+	}
+
+	// fetch releases
+	var releases []*github.RepositoryRelease
+	{
+		client := github.NewClient(nil)
+		var err error
+		releases, _, err = client.Repositories.ListReleases(context.Background(), project.Git.RepoOwner, project.Git.RepoName, nil)
+		if err != nil {
+			return fmt.Errorf("GH API: list releases: %w", err)
+		}
+	}
+
+	// compute config
+	var config assetConfig
+	{
+		config = assetConfig{
+			VersionAliases: make(map[string]assetConfigVersion),
+			SemverMapping:  make(map[string]string),
+		}
+
+		rawVersions := []string{}
+		for _, release := range releases {
+			if release.GetDraft() || release.GetPrerelease() || len(release.Assets) == 0 {
+				continue
+			}
+			rawVersions = append(rawVersions, release.GetTagName())
+		}
+		versions := make([]*semver.Version, 0)
+		for _, raw := range rawVersions {
+			version, err := semver.NewVersion(raw)
+			if err != nil {
+				logger.Warn("cannot parse version", zap.String("raw", raw), zap.Error(err))
+				continue
+			}
+			config.SemverMapping[version.String()] = raw
+			versions = append(versions, version)
+		}
+		sort.Sort(semver.Collection(versions))
+
+		for _, version := range versions {
+			raw := config.SemverMapping[version.String()]
+			var release *github.RepositoryRelease
+			for _, r := range releases {
+				if r.GetTagName() == raw {
+					release = r
+					break
+				}
+			}
+			_ = release
+			minor := fmt.Sprintf("v%d.%d", version.Major(), version.Minor())
+			major := fmt.Sprintf("v%d", version.Major())
+			configVersion := assetConfigVersion{
+				TargetVersion: raw,
+				Assets:        len(release.Assets),
+			}
+			config.VersionAliases[minor] = configVersion
+			config.VersionAliases[major] = configVersion
+			config.VersionAliases["latest"] = configVersion
+		}
+	}
+
+	// cleanup
+	{
+		config.SemverMapping = nil
+	}
+
+	// print
+	{
+		s, err := prettyjson.Marshal(config)
+		if err != nil {
+			return fmt.Errorf("json marshal error: %w", err)
+		}
+		fmt.Println(string(s))
+	}
+	return nil
+}

main.go

@@ -56,7 +56,8 @@ var (
 	infoFs              = flag.NewFlagSet("doctor", flag.ExitOnError)
 	maintenanceFs       = flag.NewFlagSet("maintenance", flag.ExitOnError)
 	versionFs           = flag.NewFlagSet("version", flag.ExitOnError)
-	templatePostCloneFs = flag.NewFlagSet("tmeplate-post-clone", flag.ExitOnError)
+	templatePostCloneFs = flag.NewFlagSet("template-post-clone", flag.ExitOnError)
+	assetsConfigFs      = flag.NewFlagSet("assets-config", flag.ExitOnError)
 	opts                Opts
 
 	logger *zap.Logger
@@ -94,6 +95,7 @@ func run(args []string) error {
 			{Name: "maintenance", Exec: doMaintenance, FlagSet: maintenanceFs, ShortHelp: "perform various maintenance tasks (write)", ShortUsage: "maintenance [opts] <path...>"},
 			{Name: "version", Exec: doVersion, FlagSet: versionFs, ShortHelp: "show version and build info", ShortUsage: "version"},
 			{Name: "template-post-clone", Exec: doTemplatePostClone, FlagSet: templatePostCloneFs, ShortHelp: "replace template", ShortUsage: "template-post-clone [opts] <path...>"},
+			{Name: "assets-config", Exec: doAssetsConfig, FlagSet: assetsConfigFs, ShortHelp: "generate a configuration for assets", ShortUsage: "assets-config [opts] <path...>"},
 		},
 		Exec: func(ctx context.Context, args []string) error {
 			return flag.ErrHelp