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A collection of functions that map to oft-used functionality on GitHub

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Workflows for GitHub Sample App

This app brings oft-used GitHub functionality - such as creating new issues - to Slack using functions and workflows.

Guide Outline:


Supported Workflows

  • Create new issue: Create and assign new issues in repositories.

Setup

Before getting started, make sure you have a development workspace where you have permissions to install apps. If you don’t have one set up, go ahead and create one. Also, please note that the workspace requires any of the Slack paid plans.

Install the Slack CLI

To use this sample, you first need to install and configure the Slack CLI. Step-by-step instructions can be found in our Quickstart Guide.

Clone the Sample App

Start by cloning this repository:

# Clone this project onto your machine
$ slack create my-github-app -t slack-samples/deno-github-functions

# Change into this project directory
$ cd my-github-app

Register a GitHub App

With external authentication you can connect your GitHub account to your Slack app to easily access the GitHub API from a custom function, creating a base for programmatic personalizations!

Connecting your GitHub account with external auth allows your application to perform the API calls used by functions as though it was from this GitHub account. This means all issues created from the Create GitHub issue workflow will appear to have been created by the account used when authenticating.

Create an OAuth App on GitHub

Begin by creating a new OAuth App from your developer settings on GitHub using any Application name and Homepage URL you'd like, but leaving Enable Device Flow unchecked.

The Authorization callback URL must be set to https://oauth2.slack.com/external/auth/callback to later exchange tokens and complete the OAuth2 handshake.

Once you're satisfied with these configurations, go ahead and click Register application!

Add your GitHub Client ID

Start by renaming the .env.example file at the top level of your project to .env, being sure not to commit this file to version control. This file will store sensitive, app-specific variables that are determined by the environment being used.

From your new GitHub app's dashboard, copy the Client ID and paste it as the value for GITHUB_CLIENT_ID in the .env file. This value will be used in external_auth/github_provider.ts – the custom OAuth2 provider definition for this GitHub app.

Once complete, use slack run or slack deploy to update your local or hosted app!

Note: Unlike environment variables used at runtime, this variable is only used when generating your app manifest. Therefore, you do not need to use the slack env add command to set this value for deployed apps.

Generate a Client Secret

Returning to your GitHub app's dashboard, press Generate a new client secret then run the following command, replacing GITHUB_CLIENT_SECRET with your own secret:

$ slack external-auth add-secret --provider github --secret GITHUB_CLIENT_SECRET

When prompted to select an app, choose the (local) app only if you're running the app locally.

Initiate the OAuth2 Flow

With your GitHub OAuth application created and the Client ID and secret set, you're ready to initate the OAuth flow!

If all the right values are in place, then the following command will prompt you to choose an app, select a provider (hint: choose the github one), then pick the GitHub account you want to authenticate with:

$ slack external-auth add

Note: when working with repositories that are part of an organization, be sure to grant access to that organization when authorizing your OAuth app.

After you've added your authentication, you'll need to assign it to the #/workflows/create_new_issue_workflow workflow using the following command:

$ slack external-auth select-auth

Once you've successfully connected your account, you're almost ready to create a link into your workflow!

Collaborating with External Authentication

When developing collaboratively on a deployed app, the external authentication tokens used for your app will be shared by all collaborators. For this reason, we recommend creating your GitHub OAuth App using an organization account so all collaborators can access the same account.

Local development does not require a shared account, as each developer will have their own local app and can individually add their own external authentication tokens.

Configure Outgoing Domains

Hosted custom functions must declare which outgoing domains are used when making network requests, including Github API calls. api.github.com is already configured as an outgoing domain in this sample's manifest. If your organization uses a separate Github Enterprise to make API calls to, add that domain to the outgoingDomains array in manifest.ts.

Create a Link Trigger

Triggers are what cause workflows to run. These triggers can be invoked by a user, or automatically as a response to an event within Slack.

A link trigger is a type of Trigger that generates a Shortcut URL which, when posted in a channel or added as a bookmark, becomes a link. When clicked, the link trigger will run the associated workflow.

Link triggers are unique to each installed version of your app. This means that Shortcut URLs will be different across each workspace, as well as between locally run and deployed apps. When creating a trigger, you must select the Workspace that you'd like to create the trigger in. Each Workspace has a development version (denoted by (local)), as well as a deployed version.

To create a link trigger for the "Create New Issue" workflow, run the following command:

$ slack trigger create --trigger-def triggers/create_new_issue_shortcut.ts

After selecting a Workspace, the output provided will include the link trigger Shortcut URL. Copy and paste this URL into a channel as a message, or add it as a bookmark in a channel of the workspace you selected.

Note: this link won't run the workflow until the app is either running locally or deployed! Read on to learn how to run your app locally and eventually deploy it to Slack hosting.

Running Your Project Locally

While building your app, you can see your changes propagated to your workspace in real-time with slack run. In both the CLI and in Slack, you'll know an app is the development version if the name has the string (local) appended.

# Run app locally
$ slack run

Connected, awaiting events

Once running, click the previously created Shortcut URL associated with the (local) version of your app. This should start a workflow that opens a form used to create a new GitHub issue!

To stop running locally, press <CTRL> + C to end the process.

Deploying Your App

Once you're done with development, you can deploy the production version of your app to Slack hosting using slack deploy:

$ slack deploy

After deploying, create a new link trigger for the production version of your app (not appended with (local)). Once the trigger is invoked, the workflow should run just as it did in when developing locally.

Viewing Activity Logs

Activity logs for the production instance of your application can be viewed with the slack activity command:

$ slack activity

Project Structure

manifest.ts

The app manifest contains the app's configuration. This file defines attributes like app name and description.

slack.json

Used by the CLI to interact with the project's SDK dependencies. It contains script hooks that are executed by the CLI and implemented by the SDK.

/functions

Functions are reusable building blocks of automation that accept inputs, perform calculations, and provide outputs. Functions can be used independently or as steps in workflows.

/workflows

A workflow is a set of steps that are executed in order. Each step in a Workflow is a function.

Workflows can be configured to run without user input or they can collect input by beginning with a form before continuing to the next step.

/triggers

Triggers determine when workflows are executed. A trigger file describes a scenario in which a workflow should be run, such as a user pressing a button or when a specific event occurs.

Resources

To learn more about developing with the CLI, you can visit the following guides:

To view all documentation and guides available, visit the Overview page.