Build Your Own GitHub Bot with Gidgethub

An introduction about bots and automations on GitHub, and how to build one for yourself using gidgethub library.
Gidgethub version 4.0 provides support for GitHub actions, and version 4.1.0 provides support for GitHub Apps.
Check my detailed tutorial: https://github-app-tutorial.readthedocs.io/en/latest/
Presented as a lightning talk at PyLadies Seattle on April 2020

Transcript

1. PyLadies Seattle - April 2020
   Build Your Own GitHub Bot
   With Gidgethub
   @mariatta
   

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2. What are GitHub bots?
   Applications that runs automations on GitHub using web hooks and APIs
   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   PyLadies Seattle - April 2020

   

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3. GitHub Bots IRL
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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4. GitHub Bots IRL
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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5. How Does it Work?
   Pull request (opened, closed, labeled)
   Status (pending, success, failure)
   Pull request review (submitted, dismissed)
   …
   Events
   GitHub
   Webservice
   Docs: https://developer.github.com/webhooks
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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6. How Does it Work?
   Create a pull request
   Merge a pull request
   Comment on a pull request
   Apply labels to pull request
   …
   APIs
   
   Webservice
   GitHub
   Docs: https://developer.github.com/v3
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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7. Gidgethub
   Async Python Library for working with GitHub APIs
   Works on Python 3.6+
   Support for aiohttp, tornado, and httpx
   License: Apache 2.0
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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8. Gidgethub for REST API calls
   import requests
   # construct the request headers
   request_headers = {
   "User-Agent": "cool-octocat-app",
   "Authorization": "token abcde",
   "Accept": "application/vnd.github.v3+json"
   }
   # make an API call
   url = "https://api.github.com/repos/mariatta/"
   "gidgethub/strange-relationship/issues"
   response = requests.get(
   url,
   headers=request_headers
   )
   from gidgethub.aiohttp import GitHubAPI
   async with aiohttp.ClientSession() as session:
   gh = GitHubAPI(
   session,
   "cool-octocat-app",
   oauth_token="abcde"
   )
   response = await gh.getitem(
   '/repos/mariatta/strange-relationship/
   issues'
   )
   With requests With gidgethub / aiohttp
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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9. Gidgethub for responding to webhooks
   @router.register("pull_request", action="opened")
   @router.register("pull_request", action="reopened")
   async def close_pr(event, gh, *args, **kwargs):
   await gh.patch(
   event.data[“pull_request"]["url"],
   data= {"state": "closed"}
   )
   • Provides routings for handling web
   hook events
   • Verifies the webhook secret and
   payload delivery headers
   PyLadies Seattle - April 2020

   Build Your Own GitHub Bot with Gidgethub
 @mariatta
   

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10. Support for GitHub Apps
    (new in v 4.1.0)
    from gidgethub.apps import get_jwt
    private_key = """-----BEGIN RSA PRIVATE KEY-----
    zBgqFIin/uQEb0he006F9pNC6Kga0AMY5b0cCdZ4ge9qyFro2eVA
    ...
    -----END RSA PRIVATE KEY-----
    """
    token = get_jwt(app_id=123, private_key=private_key)
    data = gh.getitem(
    "/app/installations",
    jwt=token,
    accept="application/vnd.github.machine-man-preview+json",
    )
    PyLadies Seattle - April 2020

    Build Your Own GitHub Bot with Gidgethub
 @mariatta
    

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11. Support for GitHub Apps
    (new in v 4.1.0)
    from gidgethub.apps import get_installation_access_token
    private_key = """-----BEGIN RSA PRIVATE KEY-----
    zBgqFIin/uQEb0he006F9pNC6Kga0AMY5b0cCdZ4ge9qyFro2eVA
    ...
    -----END RSA PRIVATE KEY-----
    """
    access_token_response = await get_installation_access_token(
    installation_id=123,
    app_id=456,
    private_key=private_key
    )
    data = await gh.getitem("/rate_limit", oauth_token=access_token_response["token"])
    PyLadies Seattle - April 2020

    Build Your Own GitHub Bot with Gidgethub
 @mariatta
    

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12. Support for GitHub Actions
    (new in v 4.0.0)
    gidgethub.actions.workspace()
    - Returns a pathlib.Path object representing the GitHub Workspace
    gidgethub.actions.event()
    - Returns the webhook event data
    gidgethub.actions.command()
    - Issue a workflow command
    PyLadies Seattle - April 2020

    Build Your Own GitHub Bot with Gidgethub
 @mariatta
    

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13. Build Your Own Bot
    https://github-app-tutorial.readthedocs.io/
    https://gidgethub.readthedocs.io
    PyLadies Seattle - April 2020

    Build Your Own GitHub Bot with Gidgethub
 @mariatta
    

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14. Thanks!
    @mariatta | mariatta@python.org
    PyLadies Seattle - April 2020

    Build Your Own GitHub Bot with Gidgethub
 @mariatta
    

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