Make it a Go app

Author: leofeyer

.github/workflows/release.yml

@@ -0,0 +1,16 @@
+name: release
+
+on:
+  push:
+    tags:
+      - '*'
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: cli/[email protected]

.gitignore

@@ -0,0 +1 @@
+/gh-changelog

README.md

@@ -1,26 +1,24 @@
 ## `gh changelog`
 
-`gh changelog` is a GitHub CLI extension to generate a changelog from the PRs
-of a milestone.
+`gh changelog` is a GitHub CLI extension to generate a changelog from the pull
+requests of a milestone.
 
-## Usage
-
-```bash
-$ gh changelog --help
+## Installation
 
-Usage:  gh changelog {<milestone>} [options]
+Make sure you have `gh` and `git` installed. Then run:
 
-Options:
-  -u, --unreleased   Set a version number for the unreleased changes
-  -h, --help         Display the help information
+```bash
+$ gh extension install leofeyer/gh-changelog
 ```
 
-## Installation
+## Usage
 
-Make sure you have `gh` and `git` installed.
+```bash
+$ gh changelog 1.2
+```
 
-Then run:
+You can optionally specify a version number for unreleased changes:
 
 ```bash
-$ gh extension install leofeyer/gh-changelog
+$ gh changelog 1.2 1.2.6
 ```

api/changelog.go

@@ -0,0 +1,311 @@
+package api
+
+import (
+	"encoding/csv"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os/exec"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/briandowns/spinner"
+	"github.com/cli/go-gh"
+	"github.com/leofeyer/gh-changelog/util"
+	"github.com/natefinch/atomic"
+)
+
+type Item struct {
+	Time   string
+	Title  string
+	Type   string
+	Number int
+	Url    string
+	Author string
+}
+
+func Changelog(milestone string, version string) error {
+	s := spinner.New(spinner.CharSets[11], 120*time.Millisecond)
+	s.Start()
+
+	owner, err := getOwner()
+	if err != nil {
+		s.Stop()
+		return err
+	}
+
+	repo, err := getRepo()
+	if err != nil {
+		s.Stop()
+		return err
+	}
+
+	items, err := getItems(milestone, owner, repo)
+	if err != nil {
+		s.Stop()
+		return err
+	}
+
+	r := strings.NewReader(getContent(items, owner, repo, version))
+	atomic.WriteFile("./CHANGELOG.md", r)
+
+	s.Stop()
+	fmt.Println("The CHANGELOG.md file has been updated.")
+	return nil
+}
+
+func getItems(milestone string, owner string, repo string) ([]Item, error) {
+	tags, err := getTags(milestone)
+	if err != nil {
+		return nil, err
+	}
+
+	features, err := search(milestone, "feature", owner, repo)
+	if err != nil {
+		return nil, err
+	}
+
+	issues, err := search(milestone, "bug", owner, repo)
+	if err != nil {
+		return nil, err
+	}
+
+	var items []Item
+	items = append(items, tags...)
+	items = append(items, features...)
+	items = append(items, issues...)
+
+	sort.Slice(items, func(i, j int) bool {
+		return items[i].Time > items[j].Time // reverse sort
+	})
+
+	return items, nil
+}
+
+func getOwner() (string, error) {
+	data, _, err := gh.Exec("repo", "view", "--json", "owner")
+	if err != nil {
+		return "", err
+	}
+
+	type Result struct {
+		Owner struct {
+			Login string `json:"login"`
+		}
+	}
+
+	var r Result
+
+	err = json.Unmarshal(data.Bytes(), &r)
+	if err != nil {
+		return "", err
+	}
+
+	return r.Owner.Login, nil
+}
+
+func getRepo() (string, error) {
+	data, _, err := gh.Exec("repo", "view", "--json", "name")
+	if err != nil {
+		return "", err
+	}
+
+	type Result struct {
+		Name string `json:"name"`
+	}
+
+	var r Result
+
+	err = json.Unmarshal(data.Bytes(), &r)
+	if err != nil {
+		return "", err
+	}
+
+	return r.Name, nil
+}
+
+func getTags(milestone string) ([]Item, error) {
+	cmd := "TZ=UTC0 git tag"
+	cmd += " --list " + milestone + ".*"
+	cmd += " --sort=-creatordate"
+	cmd += " --format '%(creatordate:format-local:%Y-%m-%dT%H:%M:%SZ),%(refname:short)'"
+
+	out, err := exec.Command("bash", "-c", cmd).Output()
+	if err != nil {
+		return nil, err
+	}
+
+	var items []Item
+	r := csv.NewReader(strings.NewReader(fmt.Sprintf("%s", out)))
+
+	for {
+		fields, err := r.Read()
+		if err == io.EOF {
+			break
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		var item Item
+		item.Time = fields[0]
+		item.Title = fields[1]
+		item.Type = "tag"
+
+		items = append(items, item)
+	}
+
+	return items, nil
+}
+
+func search(milestone string, label string, owner string, repo string) ([]Item, error) {
+	var args []string
+	args = append(args, "search", "prs")
+	args = append(args, "--json", "number,title,author,url,closedAt")
+	args = append(args, "--owner", owner)
+	args = append(args, "--repo", repo)
+	args = append(args, "--milestone", milestone)
+	args = append(args, "--merged")
+	args = append(args, "--limit", "1000")
+	args = append(args, "--label", label)
+
+	data, _, err := gh.Exec(args...)
+	if err != nil {
+		return nil, err
+	}
+
+	type PullRequest struct {
+		Time   string `json:"closedAt"`
+		Title  string `json:"title"`
+		Number int    `json:"number"`
+		Url    string `json:"url"`
+		Author struct {
+			Login string `json:"login"`
+		}
+	}
+
+	var r []PullRequest
+
+	err = json.Unmarshal(data.Bytes(), &r)
+	if err != nil {
+		return nil, err
+	}
+
+	var items []Item
+
+	for i := 0; i < len(r); i++ {
+		var item Item
+		item.Time = r[i].Time
+		item.Title = r[i].Title
+		item.Type = label
+		item.Number = r[i].Number
+		item.Url = r[i].Url
+		item.Author = r[i].Author.Login
+
+		items = append(items, item)
+	}
+
+	return items, nil
+}
+
+func getContent(items []Item, owner string, repo string, version string) string {
+	var tags []string
+	var features []Item
+	var issues []Item
+
+	users := make(map[string]string)
+	prs := make(map[int]string)
+	url := "https://github.com/" + owner + "/" + repo
+
+	content := "# Changelog\n\nThis project adheres to [Semantic Versioning].\n\n"
+	content += fmt.Sprintf("## [%s] (%s)\n", version, time.Now().Format("2006-01-02"))
+
+	for i := 0; i < len(items); i++ {
+		if items[i].Type == "tag" {
+			content += addSection(features, issues)
+			content += fmt.Sprintf("\n## [%s] (%s)\n", items[i].Title, items[i].Time[0:10])
+
+			tags = append(tags, fmt.Sprintf("[%s]: %s/releases/tag/%[1]s\n", items[i].Title, url))
+			features = features[:0]
+			issues = issues[:0]
+		} else {
+			if items[i].Type == "feature" {
+				features = append(features, items[i])
+			} else if items[i].Type == "bug" {
+				issues = append(issues, items[i])
+			}
+
+			users[items[i].Author] = fmt.Sprintf("[%s]: https://github.com/%[1]s\n", items[i].Author)
+			prs[items[i].Number] = fmt.Sprintf("[#%d]: %s/pull/%[1]d\n", items[i].Number, url)
+		}
+	}
+
+	content += addSection(features, issues)
+	content += "\n[Semantic Versioning]: https://semver.org/spec/v2.0.0.html\n"
+
+	for i := 0; i < len(tags); i++ {
+		content += tags[i]
+	}
+
+	for _, k := range getUserKeys(users) {
+		content += users[k]
+	}
+
+	for _, k := range getPrKeys(prs) {
+		content += prs[k]
+	}
+
+	return content
+}
+
+func addSection(features []Item, issues []Item) string {
+	r := ""
+
+	if len(features) > 0 {
+		r += "\n**New features:**\n\n"
+
+		for j := 0; j < len(features); j++ {
+			r += fmt.Sprintf("- [#%d] %s ([%s])\n", features[j].Number, features[j].Title, features[j].Author)
+		}
+
+		features = features[:0]
+	}
+
+	if len(issues) > 0 {
+		r += "\n**Fixed issues:**\n\n"
+
+		for j := 0; j < len(issues); j++ {
+			r += fmt.Sprintf("- [#%d] %s ([%s])\n", issues[j].Number, issues[j].Title, issues[j].Author)
+		}
+
+		issues = issues[:0]
+	}
+
+	return r
+}
+
+func getUserKeys(users map[string]string) []string {
+	keys := make([]string, 0, len(users))
+
+	for k := range users {
+		keys = append(keys, k)
+	}
+
+	sort.Slice(keys, func(i, j int) bool { return util.SortCaseInsensitive(keys[i], keys[j]) })
+
+	return keys
+}
+
+func getPrKeys(prs map[int]string) []int {
+	keys := make([]int, 0, len(prs))
+
+	for k := range prs {
+		keys = append(keys, k)
+	}
+
+	sort.Ints(keys)
+
+	return keys
+}