Slack API: Oauth2 Integration Tutorial

1. Create a Slack App

   Start out by going to your My Apps page in Slack, and click Create New App. 

   Enter the following settings:

   1. Choose From Scratch
   2. Name the App, and select a Workspace
   3. Click Create App

   Adding Scopes

   Now that the app is created, click OAuth & Permissions on the left sidebar and then scroll down to Scopes. Under the Bot Token Scopes section, click Add an OAuth Scope. 

   Add the following scopes: 

   1. channels:join
   2. channels:read
   3. channels:manage
   4. channels:write.invites

   Installing the Slack App To Your Workspace

   Next, the app needs to be approved by a user by going through the OAuth consent screen. Scroll up to the OAuth Tokens section and click Install to WORKSPACE_NAME.

   

   Next you should see the OAuth consent screen, listing your app name and the permissions being requested. Click Allow and then the token will be generated. 

   Lastly, go to Slack and invite the bot to the channel(s) you want to interact with. Open the channel's settings and go to the Integrations tab. Click Add App, then search for the app you created and add it to the channel. The bot should now be able to add other users to this channel. 

2. Saving Token to Appsmith Datasource

   Open a new Appsmith app and click the Data icon on the left sidebar, then select the [+] to add a new Datasource and choose Authenticated API. 

   

   Configure the new Datasource as follows:

   Name	Name the datasource. If working with a team, it helps to include your own name.
   URL	conversations.list
   Authentication Type	Bearer token
   Bearer Token	token from Slack

   Notice the green lock icon on the Bearer token field. This indicates the field is encrypted on your self-hosted Appsmith server, and will never be sent to client applications. More on security here. 

   Click SAVE. Your Datasource is now connected and ready to use. 

    

3. Listing Channels

   You can now begin adding APIs under the Slack Datasource. If you're still viewing the Datasource, you can use the + New API button in the top right to add an API to it. Or go to the Queries tab and click + to add a new API, then select the Slack Datasource. You can also use cmd-shift-+ (mac) or ctrl-shift-+ (windows) to quickly add a new API. 

   You should see the URL prefilled with https://slack.com/api/ with a blue bar around it, indicating that this API is part of a Datasource and will inherit the Authentication settings. 

   Configure the API as follows:

   Name	getChannels
   URL	conversations.list
   Method	POST
   Body Type	JSON
   Body	{ "types": "public_channel", "limit": 100 }

   Click Run and you should get back a list of the public Channels in your Workspace. 

   

   Next, click the UI tab and drag in a table widget. Select the getChannels API to display the response data. 

   

4. Inviting Users to a Channel

   Next, add an Input widget above the table and name it inp_addUser. Set the label to Slack UserID. 

   Then add a Button widget and set the text to Add User. 

   

   Adding the inviteUser API

   Next, add a new API under the Slack Datasource, and name it inviteUser. 

   Configure the API as follows: 

   URL	conversations.invite
   Method	POST
   Body Type	JSON
   Body	{{ {    "channel": Table1.selectedRow.id,    "users": inp_addUser.text } }}

   

    

   Lastly, update the Add User button's onClick event to run the inviteUser API. 

   The app should be ready to test out. 

   Go to Slack and copy a member ID from the [...] menu on another user's profile. Then paste that in the input and select a channel from the table that the user is not already in. Click Add User and they should now be added to the Slack Channel. 

   You can also add the users:read scope and add an API to list users to lookup their name. Be sure to reinstall the app in Slack after changing scopes. 

    

Conclusion