Posting Message to Slack via Webhooks Integration

How can I post to slack via a restful call? 

I wrote up an article on how to have Sensu send messages to HipChat http://www.whiteboardcoder.com/2014/11/getting-sensu-to-talk-to-hipchat.html

I want to figure out how to do this in Slack.

Incoming Webhooks Integration

You can do this by using the Incoming Webhooks Integrations.

This is going to be my first integrations set up in Slack.

From Slack click open team settings

Click on Menu

Click on Integrations

 

Look for the Incoming Webhooks Integration.  Click Add.  (remember you are limited to 5 integrations for the free version of Slack)

 

Select a channel to post to.  (don't worry too much about this you can actually override it later)

Click Add Incoming Webhooks Integration

  

Nice!   They provide some how to information.

Copy the Webhook URL.   For the purposes of this write up I will just list mine as

https://hooks.slack.com/services/XXX

Then run the following curl, as a test (Change the URL to your own and the name to your own)

> curl -H "Content-type: application/json" -X POST -d '{"text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

It worked!

Customizing the name/icon

I want to customize the name/icon. How do you do that?

All you need to do is change the payload.  Add username.

{     "username": "Sensu",     "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text." }

Run this curl (replace the URL with your own)

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu", "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

That changed the name, now what about the icon?

They have two ways of doing it you can use icon_url or icon_emoji

I am going to use icon_emoji, as I believe I can upload custom emoji's

{     "username": "Sensu",     "icon_emoji": ":ghost:",     "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text." }

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu", "icon_emoji": ":ghost:", "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

There is my ghost emoji.

Upload a custom Emoji

From your team page click Menu

Click on Customize.

Enter a name, upload a file click Save new Emoji.

Oops my file was too big, it can only be 128x128 pixels

There we go.

Now run this curl

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu", "icon_emoji": ":sensu:", "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

That worked nicely. J

Sending to another room

You can use this one webhook to send message to other rooms.

I created a new room called sensu.  To send messages to this room I need to change the JSON I am sending.

{     "username": "Sensu",     "icon_emoji": ":sensu:",     "channel": "#sensu",     "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text." }

Now run this curl

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu", "icon_emoji": ":sensu:", "channel": "#sensu", "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

Sending to a specific user

Now how do I send a message to a specific user?  Just use the channel and send it to @username.

{     "username": "Sensu",     "icon_emoji": ":sensu:",     "channel": "@patrick",     "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text." }

Now run this curl

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu", "icon_emoji": ":sensu:", "channel": "@patrick", "text": "Patrick This is a line of text in a channel.\nAnd this is another line of text."}' https://hooks.slack.com/services/XXX

It became a direct message from the slackbot.

Direct message!  Nice very nice I can use this J

Getting Fancier … Attachments

I was putting using a Pagerduty integration and noticed

This nice little attention grabbing line...  How do I do this?

You can do it, and more with attachments https://api.slack.com/docs/attachments [1]

{     "username": "Sensu",     "icon_emoji": ":sensu:",     "channel": "#sensu",     "attachments": [         {             "color": "danger",             "fields": [                 {                     "title": "Event",                     "value": "This is an emergency",                     "short": false                 }             ]         }     ] }

Now run this curl

> curl -H "Content-type: application/json" -X POST -d '{"username": "Sensu","icon_emoji": ":sensu:","channel": "#sensu","attachments": [{"color": "danger","fields": [{"title": "Event","value": "This is an emergency","short": false}]}]}' https://hooks.slack.com/services/XXX

You can change the color

"color": "good",

"color": "warning",

Or you can use HEX colors

"color": "#FF69B4",

You can have multiple attachments.

{     "username": "Sensu",     "icon_emoji": ":sensu:",     "channel": "#sensu",     "attachments": [         {             "color": "danger",             "fields": [                 {                     "title": "Danger Event",                     "value": "This is an emergency",                     "short": false                 }             ]         },         {             "color": "warning",             "fields": [                 {                     "title": "Warning Event",                     "value": "This is a warning",                     "short": false                 }             ]         },         {             "color": "good",             "fields": [                 {                     "title": "Good Event",                     "value": "This is good",                     "short": false                 }             ]         }     ] }

There is a lot of other cool things you can do with attachments see https://api.slack.com/docs/attachments [1]  for some ideas.

References

[1]        Slack API

            https://api.slack.com/docs/attachments

            Accessed 3/2015