// Display a Repository dashboard.
func RepoDashboard(w http.ResponseWriter, r *http.Request, u *User, repo *Repo) error {
	branch := r.FormValue(":branch")

	// get a list of all branches
	branches, err := database.ListBranches(repo.ID)
	if err != nil {
		return err
	}

	// if no branch is provided then we'll
	// want to use a default value.
	if len(branch) == 0 {
		branch = repo.DefaultBranch()
	}

	// get a list of recent commits for the
	// repository and specific branch
	commits, err := database.ListCommits(repo.ID, branch)
	if err != nil {
		return err
	}

	// get a token that can be exchanged with the
	// websocket handler to authorize listening
	// for a stream of changes for this repository
	token := channel.Create(repo.Slug)

	data := struct {
		User     *User
		Repo     *Repo
		Branches []*Commit
		Commits  []*Commit
		Branch   string
		Token    string
	}{u, repo, branches, commits, branch, token}

	return RenderTemplate(w, "repo_dashboard.html", &data)
}

// execute will execute the build task and persist
// the results to the datastore.
func (w *worker) execute(task *BuildTask) error {
	// we need to be sure that we can recover
	// from any sort panic that could occur
	// to avoid brining down the entire application
	defer func() {
		if e := recover(); e != nil {
			task.Build.Finished = time.Now().UTC()
			task.Commit.Finished = time.Now().UTC()
			task.Build.Duration = task.Build.Finished.Unix() - task.Build.Started.Unix()
			task.Commit.Duration = task.Build.Finished.Unix() - task.Build.Started.Unix()
			task.Commit.Status = "Error"
			task.Build.Status = "Error"
			database.SaveBuild(task.Build)
			database.SaveCommit(task.Commit)
		}
	}()

	// update commit and build status
	task.Commit.Status = "Started"
	task.Build.Status = "Started"
	task.Build.Started = time.Now().UTC()
	task.Commit.Started = time.Now().UTC()

	// persist the commit to the database
	if err := database.SaveCommit(task.Commit); err != nil {
		return err
	}

	// persist the build to the database
	if err := database.SaveBuild(task.Build); err != nil {
		return err
	}

	// get settings
	settings, _ := database.GetSettings()

	// notification context
	context := &notify.Context{
		Repo:   task.Repo,
		Commit: task.Commit,
		Host:   settings.URL().String(),
	}

	// send all "started" notifications
	if task.Script.Notifications != nil {
		task.Script.Notifications.Send(context)
	}

	// Send "started" notification to Github
	if err := updateGitHubStatus(task.Repo, task.Commit); err != nil {
		log.Printf("error updating github status: %s\n", err.Error())
	}

	// make sure a channel exists for the repository,
	// the commit, and the commit output (TODO)
	reposlug := fmt.Sprintf("%s/%s/%s", task.Repo.Host, task.Repo.Owner, task.Repo.Name)
	commitslug := fmt.Sprintf("%s/%s/%s/commit/%s", task.Repo.Host, task.Repo.Owner, task.Repo.Name, task.Commit.Hash)
	consoleslug := fmt.Sprintf("%s/%s/%s/commit/%s/builds/%s", task.Repo.Host, task.Repo.Owner, task.Repo.Name, task.Commit.Hash, task.Build.Slug)
	channel.Create(reposlug)
	channel.Create(commitslug)
	channel.CreateStream(consoleslug)

	// notify the channels that the commit and build started
	channel.SendJSON(reposlug, task.Commit)
	channel.SendJSON(commitslug, task.Build)

	var buf = &bufferWrapper{channel: consoleslug}

	// append private parameters to the environment
	// variable section of the .drone.yml file, iff
	// this is not a pull request (for security purposes)
	if task.Repo.Params != nil && len(task.Commit.PullRequest) == 0 {
		for k, v := range task.Repo.Params {
			task.Script.Env = append(task.Script.Env, k+"="+v)
		}
	}

	defer func() {
		// update the status of the commit using the
		// GitHub status API.
		if err := updateGitHubStatus(task.Repo, task.Commit); err != nil {
			log.Printf("error updating github status: %s\n", err.Error())
		}
	}()

	// execute the build
	passed, buildErr := w.runBuild(task, buf)

	task.Build.Finished = time.Now().UTC()
	task.Commit.Finished = time.Now().UTC()
	task.Build.Duration = task.Build.Finished.UnixNano() - task.Build.Started.UnixNano()
	task.Commit.Duration = task.Build.Finished.UnixNano() - task.Build.Started.UnixNano()
	task.Commit.Status = "Success"
	task.Build.Status = "Success"
	task.Build.Stdout = buf.buf.String()

	// if exit code != 0 set to failure
	if passed {
//.........这里部分代码省略.........

// execute will execute the build task and persist
// the results to the datastore.
func (b *BuildTask) execute() error {
	// we need to be sure that we can recover
	// from any sort panic that could occur
	// to avoid brining down the entire application
	defer func() {
		if e := recover(); e != nil {
			b.Build.Finished = time.Now().UTC()
			b.Commit.Finished = time.Now().UTC()
			b.Build.Duration = b.Build.Finished.Unix() - b.Build.Started.Unix()
			b.Commit.Duration = b.Build.Finished.Unix() - b.Build.Started.Unix()
			b.Commit.Status = "Error"
			b.Build.Status = "Error"
			database.SaveBuild(b.Build)
			database.SaveCommit(b.Commit)
		}
	}()

	// update commit and build status
	b.Commit.Status = "Started"
	b.Build.Status = "Started"
	b.Build.Started = time.Now().UTC()
	b.Commit.Started = time.Now().UTC()

	// persist the commit to the database
	if err := database.SaveCommit(b.Commit); err != nil {
		return err
	}

	// persist the build to the database
	if err := database.SaveBuild(b.Build); err != nil {
		return err
	}

	// get settings
	settings, _ := database.GetSettings()

	// notification context
	context := &notification.Context{
		Repo:   b.Repo,
		Commit: b.Commit,
		Host:   settings.URL().String(),
	}

	// send all "started" notifications
	if b.Script.Notifications != nil {
		b.Script.Notifications.Send(context)
	}

	// make sure a channel exists for the repository,
	// the commit, and the commit output (TODO)
	reposlug := fmt.Sprintf("%s/%s/%s", b.Repo.Host, b.Repo.Owner, b.Repo.Name)
	commitslug := fmt.Sprintf("%s/%s/%s/commit/%s", b.Repo.Host, b.Repo.Owner, b.Repo.Name, b.Commit.Hash)
	consoleslug := fmt.Sprintf("%s/%s/%s/commit/%s/builds/%s", b.Repo.Host, b.Repo.Owner, b.Repo.Name, b.Commit.Hash, b.Build.Slug)
	channel.Create(reposlug)
	channel.Create(commitslug)
	channel.CreateStream(consoleslug)

	// notify the channels that the commit and build started
	channel.SendJSON(reposlug, b.Commit)
	channel.SendJSON(commitslug, b.Build)

	var buf = &bufferWrapper{channel: consoleslug}

	// append private parameters to the environment
	// variable section of the .drone.yml file
	if b.Repo.Params != nil {
		for k, v := range b.Repo.Params {
			b.Script.Env = append(b.Script.Env, k+"="+v)
		}
	}

	// execute the build
	builder := bldr.Builder{}
	builder.Build = b.Script
	builder.Repo = &r.Repo{Path: b.Repo.URL, Branch: b.Commit.Branch, Commit: b.Commit.Hash, PR: b.Commit.PullRequest, Dir: filepath.Join("/var/cache/drone/src", b.Repo.Slug)}
	builder.Key = []byte(b.Repo.PrivateKey)
	builder.Stdout = buf
	builder.Timeout = 300 * time.Minute

	defer func() {
		// update the status of the commit using the
		// GitHub status API.
		if err := updateGitHubStatus(b.Repo, b.Commit); err != nil {
			log.Printf("error updating github status: %s\n", err.Error())
		}
	}()

	buildErr := builder.Run()

	b.Build.Finished = time.Now().UTC()
	b.Commit.Finished = time.Now().UTC()
	b.Build.Duration = b.Build.Finished.UnixNano() - b.Build.Started.UnixNano()
	b.Commit.Duration = b.Build.Finished.UnixNano() - b.Build.Started.UnixNano()
	b.Commit.Status = "Success"
	b.Build.Status = "Success"
	b.Build.Stdout = buf.buf.String()

	// if exit code != 0 set to failure
//.........这里部分代码省略.........

// setup the websocket channel for the wall display
func setupWall() {
	channel.Create(channel.WallDisplay)
}