Release notes generation

go/tools/release-notes/release_notes.go

@@ -0,0 +1,200 @@
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"regexp"
+	"sort"
+	"strings"
+	"sync"
+	"text/template"
+)
+
+type label struct {
+	Name string `json:"name"`
+}
+
+type prInfo struct {
+	Labels []label `json:"labels"`
+	Number int     `json:"number"`
+	Title  string  `json:"title"`
+}
+
+const (
+	markdownTemplate = `
+{{- range $typeName, $components := . }}
+## {{ $typeName }}
+{{- range $componentName, $component := $components }} 
+### {{ $componentName}}
+{{- range $prInfo := $component }}
+ - {{ $prInfo.Title }} #{{ $prInfo.Number }}
+{{- end }}
+{{- end }}
+{{- end }}
+`
+
+	prefixType      = "Type: "
+	prefixComponent = "Component: "
+)
+
+func loadMergedPRs(from, to string) ([]string, error) {
+	cmd := exec.Command("git", "log", "--oneline", fmt.Sprintf("%s...%s", from, to))
+	out, err := cmd.Output()
+	if err != nil {
+		execErr := err.(*exec.ExitError)
+		return nil, fmt.Errorf("%s:\nstderr: %s\nstdout: %s", err.Error(), execErr.Stderr, out)
+	}
+
+	var prs []string
+	rgx := regexp.MustCompile(`Merge pull request #(\d+)`)
+	lines := strings.Split(string(out), "\n")
+	for _, line := range lines {
+		lineInfo := rgx.FindStringSubmatch(line)
+		if len(lineInfo) == 2 {
+			prs = append(prs, lineInfo[1])
+		}
+	}
+
+	sort.Strings(prs)
+	return prs, nil
+}
+
+func loadPRinfo(pr string) (prInfo, error) {
+	cmd := exec.Command("gh", "pr", "view", pr, "--json", "title,number,labels")
+	out, err := cmd.Output()
+	if err != nil {
+		execErr := err.(*exec.ExitError)
+		return prInfo{}, fmt.Errorf("%s:\nstderr: %s\nstdout: %s", err.Error(), execErr.Stderr, out)
+	}
+	var prInfo prInfo
+	err = json.Unmarshal(out, &prInfo)
+	return prInfo, err
+}
+
+func loadAllPRs(prs []string) ([]prInfo, error) {
+	errChan := make(chan error)
+	wgDone := make(chan bool)
+	prChan := make(chan string, len(prs))
+	// fill the work queue
+	for _, s := range prs {
+		prChan <- s
+	}
+	close(prChan)
+
+	var prInfos []prInfo
+
+	wg := sync.WaitGroup{}
+	mu := sync.Mutex{}
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func() {
+			// load meta data about PRs
+			defer wg.Done()
+			for b := range prChan {
+				fmt.Print(".")
+				prInfo, err := loadPRinfo(b)
+				if err != nil {
+					errChan <- err
+					break
+				}
+				mu.Lock()
+				prInfos = append(prInfos, prInfo)
+				mu.Unlock()
+			}
+		}()
+	}
+
+	go func() {
+		// wait for the loading to finish
+		wg.Wait()
+		close(wgDone)
+	}()
+
+	var err error
+	select {
+	case <-wgDone:
+		break
+	case err = <-errChan:
+		break
+	}
+
+	fmt.Println()
+	return prInfos, err
+}
+
+func groupPRs(prInfos []prInfo) map[string]map[string][]prInfo {
+	prPerType := map[string]map[string][]prInfo{}
+
+	for _, info := range prInfos {
+		var typ, component string
+		for _, lbl := range info.Labels {
+			switch {
+			case strings.HasPrefix(lbl.Name, prefixType):
+				typ = strings.TrimPrefix(lbl.Name, prefixType)
+			case strings.HasPrefix(lbl.Name, prefixComponent):
+				component = strings.TrimPrefix(lbl.Name, prefixComponent)
+			}
+		}
+		if typ == "" {
+			typ = "Other"
+		}
+		if component == "" {
+			component = "Other"
+		}
+		components, exists := prPerType[typ]
+		if !exists {
+			components = map[string][]prInfo{}
+			prPerType[typ] = components
+		}
+
+		prsPerComponentAndType := components[component]
+		components[component] = append(prsPerComponentAndType, info)
+	}
+	return prPerType
+}
+
+func writePrInfos(fileout string, prPerType map[string]map[string][]prInfo) (err error) {
+	writeTo := os.Stdout
+	if fileout != "" {
+		writeTo, err = os.OpenFile(fileout, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+		if err != nil {
+			return err
+		}
+	}
+
+	t := template.Must(template.New("markdownTemplate").Parse(markdownTemplate))
+	err = t.ExecuteTemplate(writeTo, "markdownTemplate", prPerType)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func main() {
+	from := flag.String("from", "", "from sha/tag/branch")
+	to := flag.String("to", "HEAD", "to sha/tag/branch")
+	fileout := flag.String("file", "", "file on which to write release notes, stdout if empty")
+
+	flag.Parse()
+
+	prs, err := loadMergedPRs(*from, *to)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	prInfos, err := loadAllPRs(prs)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	prPerType := groupPRs(prInfos)
+
+	err = writePrInfos(*fileout, prPerType)
+	if err != nil {
+		log.Fatal(err)
+	}
+}

go/tools/release-notes/release_notes_test.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2021 The Vitess 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 (
+	"reflect"
+	"testing"
+)
+
+func Test_groupPRs(t *testing.T) {
+	tests := []struct {
+		name    string
+		prInfos []prInfo
+		want    map[string]map[string][]prInfo
+	}{
+		{name: "Single PR info with no labels", prInfos: []prInfo{{Title: "pr 1", Number: 1}}, want: map[string]map[string][]prInfo{"Other": {"Other": []prInfo{{Title: "pr 1", Number: 1}}}}},
+		{name: "Single PR info with type label", prInfos: []prInfo{{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}}}}, want: map[string]map[string][]prInfo{"Bug": {"Other": []prInfo{{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}}}}}}},
+		{name: "Single PR info with type and component labels", prInfos: []prInfo{{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}, {Name: prefixComponent + "VTGate"}}}}, want: map[string]map[string][]prInfo{"Bug": {"VTGate": []prInfo{{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}, {Name: prefixComponent + "VTGate"}}}}}}},
+		{name: "Multiple PR infos with type and component labels", prInfos: []prInfo{
+			{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}, {Name: prefixComponent + "VTGate"}}},
+			{Title: "pr 2", Number: 2, Labels: []label{{Name: prefixType + "Feature"}, {Name: prefixComponent + "VTTablet"}}}},
+			want: map[string]map[string][]prInfo{"Bug": {"VTGate": []prInfo{{Title: "pr 1", Number: 1, Labels: []label{{Name: prefixType + "Bug"}, {Name: prefixComponent + "VTGate"}}}}}, "Feature": {"VTTablet": []prInfo{{Title: "pr 2", Number: 2, Labels: []label{{Name: prefixType + "Feature"}, {Name: prefixComponent + "VTTablet"}}}}}}},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := groupPRs(tt.prInfos); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("groupPRs() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}