Merge pull request #65 from keybase/david/bot-announce

Add feature for bot to announce itself at startup

docs/env.md

@@ -86,6 +86,26 @@ export CHAT_CHANNEL="team.prod#ssh-provision"
 export CHAT_CHANNEL="team.ssh_bot#general"
 ```
 
+### Announcement
+
+The `ANNOUNCEMENT` environment variable contains a string that will be announced in all of the configured teams when
+the bot is started. This is useful if you would like the bot to announce the fact it has started and granted access in 
+a given team. The `ANNOUNCEMENT` environment variable supports a number of templating variables that will be instantiated
+based off of the current config. These are:
+
+* `{USERNAME}` will be replaced with the username of the bot
+* `{CURRENT_TEAM}` will be replaced with the team that the message is being sent in
+* `{TEAMS}` will be replaced with the comma separated list of teams that the bot is running in
+
+Examples:
+
+```bash
+export ANNOUNCEMENT="SSH CA bot starting up..."
+export ANNOUNCEMENT="Hello! I'm {USERNAME} and I'm an SSH bot! See github.com/keybase/bot-sshca for information on using Keybase for SSH."
+export ANNOUNCEMENT="Hello! I'm {USERNAME} and I'm an SSH bot! I'm currently listening in {TEAMS}."
+export ANNOUNCEMENT="Hello! I'm {USERNAME} and I'm an SSH bot! Being in {CURRENT_TEAM} will grant you SSH access to certain servers. Reach out to @dworken for more information."
+```
+
 ## Developer Options
 
 These environment variables are mainly useful for dev work. For security reasons, it is recommended always to run a 

src/keybaseca/bot/bot.go

@@ -36,13 +36,18 @@ func GetUsername(conf config.Config) (string, error) {
 	return username, nil
 }
 
-// Start the keybaseca bot in an infinite loop. Does not return unless it encounters an error.
+// Start the keybaseca bot in an infinite loop. Does not return unless it encounters an unrecoverable error.
 func StartBot(conf config.Config) error {
 	kbc, err := GetKBChat(conf)
 	if err != nil {
 		return fmt.Errorf("error starting Keybase chat: %v", err)
 	}
 
+	err = sendAnnouncementMessage(conf, kbc)
+	if err != nil {
+		return fmt.Errorf("failed to start bot due to error while sending announcement: %v", err)
+	}
+
 	sub, err := kbc.ListenForNewTextMessages()
 	if err != nil {
 		return fmt.Errorf("error subscribing to messages: %v", err)
@@ -144,3 +149,44 @@ func isConfiguredTeam(conf config.Config, teamName string, channelName string) b
 	}
 	return false
 }
+
+type AnnouncementTemplateValues struct {
+	Username    string
+	CurrentTeam string
+	Teams       []string
+}
+
+func buildAnnouncement(template string, values AnnouncementTemplateValues) string {
+	replacements := map[string]string{
+		"{USERNAME}":     values.Username,
+		"{CURRENT_TEAM}": values.CurrentTeam,
+		"{TEAMS}":        strings.Join(values.Teams, ", "),
+	}
+
+	templatedMessage := template
+	for templateStr, templateVal := range replacements {
+		templatedMessage = strings.Replace(templatedMessage, templateStr, templateVal, -1)
+	}
+
+	return templatedMessage
+}
+
+func sendAnnouncementMessage(conf config.Config, kbc *kbchat.API) error {
+	if conf.GetAnnouncement() == "" {
+		// No announcement to send
+		return nil
+	}
+	for _, team := range conf.GetTeams() {
+		announcement := buildAnnouncement(conf.GetAnnouncement(),
+			AnnouncementTemplateValues{Username: kbc.GetUsername(),
+				CurrentTeam: team,
+				Teams:       conf.GetTeams()})
+
+		var channel *string
+		_, err := kbc.SendMessageByTeamName(team, announcement, channel)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

src/keybaseca/bot/bot_test.go

@@ -0,0 +1,24 @@
+package bot
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestBuildAnnouncement(t *testing.T) {
+	values := AnnouncementTemplateValues{Username: "my_username", CurrentTeam: "my_cur_team", Teams: []string{"my_team1", "my_team2"}}
+
+	require.Equal(t, "",
+		buildAnnouncement("", values))
+	require.Equal(t, "no templates",
+		buildAnnouncement("no templates", values))
+	require.Equal(t, "repeated my_username my_username my_username",
+		buildAnnouncement("repeated {USERNAME} {USERNAME} {USERNAME}", values))
+	require.Equal(t, "all my_username my_cur_team my_team1, my_team2",
+		buildAnnouncement("all {USERNAME} {CURRENT_TEAM} {TEAMS}", values))
+	require.Equal(t, "bogus {FOO}",
+		buildAnnouncement("bogus {FOO}", values))
+	require.Equal(t, "double-is-not-escape {my_username}",
+		buildAnnouncement("double-is-not-escape {{USERNAME}}", values))
+}

src/keybaseca/config/config.go

@@ -27,6 +27,7 @@ type Config interface {
 	GetChannelName() string
 	GetLogLocation() string
 	GetStrictLogging() bool
+	GetAnnouncement() string
 	DebugString() string
 }
 
@@ -250,6 +251,11 @@ func (ef *EnvConfig) GetChannelName() string {
 	return channel
 }
 
+// Get the announcement string used when the bot is started up. May be empty.
+func (ef *EnvConfig) GetAnnouncement() string {
+	return os.Getenv("ANNOUNCEMENT")
+}
+
 // Dump this EnvConfig to a string for debugging purposes
 func (ef *EnvConfig) DebugString() string {
 	return fmt.Sprintf("CAKeyLocation='%s'; KeybaseHomeDir='%s'; KeybasePaperKey='%s'; KeybaseUsername='%s'; "+

tests/envFiles/test_env_1

@@ -7,3 +7,4 @@ export KEYBASE_PAPERKEY="$BOT_PAPERKEY"
 export KEYBASE_USERNAME="$BOT_USERNAME"
 export CHAT_CHANNEL="$SUBTEAM.ssh#ssh-provision"
 export CA_KEY_LOCATION="/shared/keybase-ca-key"
+export ANNOUNCEMENT='Hello my name is {USERNAME}. This is {CURRENT_TEAM} and the configured teams are {TEAMS}'