github.com/shashidharatd/test-infra@v0.0.0-20171006011030-71304e1ca560/experiment/commenter/main.go

/*
Copyright 2017 The Kubernetes 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.
*/

// Commenter provides a way to --query for issues and append a --comment to matches.
//
// The --token determines who interacts with github.
// By default commenter runs in dry mode, add --confirm to make it leave comments.
// The --updated, --include-closed, --ceiling options provide minor safeguards
// around leaving excessive comments.
package main

import (
	"bytes"
	"flag"
	"fmt"
	"io/ioutil"
	"log"
	"net/url"
	"regexp"
	"strconv"
	"strings"
	"text/template"
	"time"

	"k8s.io/test-infra/prow/github"
)

const (
	TemplateHelp = `--comment is a golang text/template if set.
	Valid placeholders:
		.Org - github org
		.Repo - github repo
		.Number - issue number
	Advanced (see kubernetes/test-infra/prow/github/types.go):
		.Issue.User.Login - github account
		.Issue.Title
		.Issue.State
		.Issue.HTMLURL
		.Issue.Assignees - list of assigned .Users
		.Issue.Labels - list of applied labels (.Name)
`
)

func flagOptions() options {
	o := options{}
	flag.StringVar(&o.query, "query", "", "See https://help.github.com/articles/searching-issues-and-pull-requests/")
	flag.DurationVar(&o.updated, "updated", 2*time.Hour, "Filter to issues unmodified for at least this long if set")
	flag.BoolVar(&o.includeClosed, "include-closed", false, "Match closed issues if set")
	flag.BoolVar(&o.confirm, "confirm", false, "Mutate github if set")
	flag.StringVar(&o.comment, "comment", "", "Append the following comment to matching issues")
	flag.BoolVar(&o.useTemplate, "template", false, TemplateHelp)
	flag.IntVar(&o.ceiling, "ceiling", 3, "Maximum number of issues to modify, 0 for infinite")
	flag.StringVar(&o.endpoint, "endpoint", "https://api.github.com", "GitHub's API endpoint")
	flag.StringVar(&o.token, "token", "", "Path to github token")
	flag.Parse()
	return o
}

type meta struct {
	Number int
	Org    string
	Repo   string
	Issue  github.Issue
}

type options struct {
	asc           bool
	ceiling       int
	comment       string
	includeClosed bool
	useTemplate   bool
	query         string
	sort          string
	endpoint      string
	token         string
	updated       time.Duration
	confirm       bool
}

func parseHTMLURL(url string) (string, string, int, error) {
	// Example: https://github.com/batterseapower/pinyin-toolkit/issues/132
	re := regexp.MustCompile(`.+/(.+)/(.+)/(issues|pull)/(\d+)$`)
	mat := re.FindStringSubmatch(url)
	if mat == nil {
		return "", "", 0, fmt.Errorf("failed to parse: %s", url)
	}
	n, err := strconv.Atoi(mat[4])
	if err != nil {
		return "", "", 0, err
	}
	return mat[1], mat[2], n, nil
}

func makeQuery(query string, includeClosed bool, minUpdated time.Duration) (string, error) {
	parts := []string{query}
	if !includeClosed {
		if strings.Contains(query, "is:closed") {
			return "", fmt.Errorf("--query='%s' containing is:closed requires --include-closed", query)
		}
		parts = append(parts, "is:open")
	} else if strings.Contains(query, "is:open") {
		return "", fmt.Errorf("--query='%s' should not contain is:open when using --include-closed", query)
	}
	if minUpdated != 0 {
		latest := time.Now().Add(-minUpdated)
		parts = append(parts, "updated:<="+latest.Format(time.RFC3339))
	}
	return strings.Join(parts, " "), nil
}

type client interface {
	CreateComment(owner, repo string, number int, comment string) error
	FindIssues(query, sort string, asc bool) ([]github.Issue, error)
}

func main() {
	log.SetFlags(log.LstdFlags | log.Lshortfile)
	o := flagOptions()

	if o.query == "" {
		log.Fatal("empty --query")
	}
	if o.token == "" {
		log.Fatal("empty --token")
	}
	if o.comment == "" {
		log.Fatal("empty --comment")
	}
	b, err := ioutil.ReadFile(o.token)
	if err != nil {
		log.Fatalf("cannot read --token: %v", err)
	}
	_, err = url.Parse(o.endpoint)
	if err != nil {
		log.Fatal("Must specify a valid --endpoint URL.")
	}

	var c client
	tok := strings.TrimSpace(string(b))
	if o.confirm {
		c = github.NewClient(tok, o.endpoint)
	} else {
		c = github.NewDryRunClient(tok, o.endpoint)
	}

	query, err := makeQuery(o.query, o.includeClosed, o.updated)
	if err != nil {
		log.Fatalf("Bad query: %v", err)
	}
	sort := ""
	asc := false
	if o.updated > 0 {
		sort = "updated"
		asc = true
	}
	commenter := makeCommenter(o.comment, o.useTemplate)
	if err := run(c, query, sort, asc, commenter, o.ceiling); err != nil {
		log.Fatalf("Failed run: %v", err)
	}
}

func makeCommenter(comment string, useTemplate bool) func(meta) (string, error) {
	if !useTemplate {
		return func(_ meta) (string, error) {
			return comment, nil
		}
	}
	t := template.Must(template.New("comment").Parse(comment))
	return func(m meta) (string, error) {
		out := bytes.Buffer{}
		err := t.Execute(&out, m)
		return string(out.Bytes()), err
	}
}

func run(c client, query, sort string, asc bool, commenter func(meta) (string, error), ceiling int) error {
	log.Printf("Searching: %s", query)
	issues, err := c.FindIssues(query, sort, asc)
	if err != nil {
		return fmt.Errorf("search failed: %v", err)
	}
	problems := []string{}
	log.Printf("Found %d matches", len(issues))
	for n, i := range issues {
		if ceiling > 0 && n == ceiling {
			log.Printf("Stopping at --ceiling=%d of %d results", n, len(issues))
			break
		}
		log.Printf("Matched %s (%s)", i.HTMLURL, i.Title)
		org, repo, number, err := parseHTMLURL(i.HTMLURL)
		if err != nil {
			msg := fmt.Sprintf("Failed to parse %s: %v", i.HTMLURL, err)
			log.Print(msg)
			problems = append(problems, msg)
		}
		comment, err := commenter(meta{Number: number, Org: org, Repo: repo, Issue: i})
		if err != nil {
			msg := fmt.Sprintf("Failed to create comment for %s/%s#%d: %v", org, repo, number, err)
			log.Print(msg)
			problems = append(problems, msg)
			continue
		}
		if err := c.CreateComment(org, repo, number, comment); err != nil {
			msg := fmt.Sprintf("Failed to apply comment to %s/%s#%d: %v", org, repo, number, err)
			log.Print(msg)
			problems = append(problems, msg)
			continue
		}
		log.Printf("Commented on %s", i.HTMLURL)
	}
	if len(problems) > 0 {
		return fmt.Errorf("encoutered %d failures: %v", len(problems), problems)
	}
	return nil
}