update slack utility and instructions, fix config loading (#32)

README.md

@@ -54,7 +54,7 @@ Once tokens have been obtained, `zat -no-server` will perform only archival duti
 * [Optional] Obtain Slack credentials
   * [Create an App](https://api.slack.com/apps?new_app=1)
     * Add Permissions > Scopes > Bot Token Scopes > Add An Oauth Scope granting: `channels:read`, `chat:write`, `chat:write.public`
-  * Save the Bot User OAuth Access Token to `slack.config.json` with content:
+  * Save the Bot User OAuth Access Token (under OAuth & Permissions) to `slack.config.json` with content:
     ```json
     {
       "token":             "your-token"
@@ -133,8 +133,11 @@ The slack configuration is the ID of the channel where the message should be sen
 ```
 $ go build ./cmd/slack/listchannels
 $ ./listchannels
-0: {GroupConversation:{Conversation:{ID:CAAAAAAAA Created:"Sat Mar 10" IsOpen:false LastRead: Latest:<nil> UnreadCount:0 UnreadCountDisplay:0 IsGroup:false IsShared:false IsIM:false IsExtShared:false IsOrgShared:false IsPendingExtShared:false IsPrivate:false IsMpIM:false Unlinked:0 NameNormalized:zat NumMembers:1 Priority:0 User:} Name:zat Creator:U99999999 IsArchived:false Members:[] Topic:{Value: Creator: LastSet:"Wed Dec 31"} Purpose:{Value:Zat Discussion Creator:U99999999 LastSet:"Sat Mar 10"}} IsChannel:true IsGeneral:false IsMember:false Locale:}
-1: {GroupConversation:{Conversation:{ID:CAAAAAAAA Created:"Sat Mar 10" IsOpen:false LastRead: Latest:<nil> UnreadCount:0 UnreadCountDisplay:0 IsGroup:false IsShared:false IsIM:false IsExtShared:false IsOrgShared:false IsPendingExtShared:false IsPrivate:false IsMpIM:false Unlinked:0 NameNormalized:welcome NumMembers:1 Priority:0 User:} Name:welcome Creator:U99999999 IsArchived:false Members:[] Topic:{Value: Creator:U99999999 LastSet:"Sat Mar 10"} Purpose:{Value:This channel is for workspace-wide communication and announcements. All members are in this channel. Creator:U99999999 LastSet:"Sat Mar 10"}} IsChannel:true IsGeneral:true IsMember:false Locale:}
+CAAAAAAAA general
+CAAAAAAAB zat
+
+One method for finding private channel IDs is to open Slack in a web browser and look at `$$('.p-channel_sidebar__static_list__item')` elements.
+The application's bot user will need to be invited to the private channel to post messages there.
 ```
 
 `cmd/slack/chat` can assist in verifying permissions are correct.

cmd/slack/listchannels/listchannels.go

@@ -23,11 +23,21 @@ func main() {
 		logger.Fatal("failed to create slack api client")
 	}
 
-	channels, _, err := api.GetConversations(&slackapi.GetConversationsParameters{})
-	if err != nil {
-		panic(err)
-	}
-	for i, channel := range channels {
-		fmt.Printf("%d: %+v\n", i, channel)
+	next := ""
+	for i := 0; i == 0 || next != ""; i++ {
+		channels, nextCursor, err := api.GetConversations(
+			&slackapi.GetConversationsParameters{
+				Cursor:          next,
+				ExcludeArchived: "true",
+				Limit: 100,
+			},
+		)
+		if err != nil {
+			panic(err)
+		}
+		for _, channel := range channels {
+			fmt.Printf("%s %s\n", channel.ID, channel.NameNormalized)
+		}
+		next = nextCursor
 	}
 }

main.go

@@ -575,7 +575,7 @@ func main() {
 	if err != nil {
 		logger.Fatal(err)
 	}
-	slackClient, _ := slack.NewClientFromEnvOrFile(logger, *cfgDir, slackapi.OptionHTTPClient(http.DefaultClient))
+	slackClient, _ := slack.NewClientFromEnvOrFile(logger, path.Join(*cfgDir, cmd.SlackConfigPath), slackapi.OptionHTTPClient(http.DefaultClient))
 	rp := runParams{
 		minDuration: *minDuration,
 		since:       *since,