gidgethub.sansio — sans-I/O support

Webhook events

Webhook events are represented by Event objects. The expectation is that a server will receive an HTTP request from GitHub and then use Event.from_http() to create an Event instance. For example:

import os
import aiohttp.web

SECRET = os.environ["GITHUB_SECRET"]

async def index(request):
    headers = request.headers
    body = await request.read()
    event = gidgethub.Event.from_http(headers, body,
                                      secret=SECRET)

This is not required, though, as the Event class can be constructed in a more traditional way. The validate_event() function is also provided to allow for manual validation that a event came from a supported project without requiring the use of the Event class.

gidgethub.sansio.validate_event(payload, *, signature, secret)

Validate the signature of a webhook event.

ValidationFailure is raised if the signature is malformed or if the provided signature does not match the calculated signature using payload and secret. If the validation passes then no exception is raised (i.e. there’s no need to check the return value of the function as an exception is raised if validation fails).

class gidgethub.sansio.Event(data, *, event, delivery_id)

Representation of a GitHub webhook event.

data

The payload of the event.

event

The string representation of the triggering event.

delivery_id

The unique ID of the event.

classmethod from_http(headers, body, *, secret=None)

Construct an Event instance from HTTP headers and body data.

The headers mapping is expected to support lowercase keys.

Since this method assumes the body of the HTTP request is only of the [content type that GitHub sends](https://developer.github.com/webhooks/creating/#content-type), BadRequest is raised if the content type is unexpected.

If the appropriate headers are provided for event validation, then the secret argument is required. Any failure in validation (including not providing the secret argument) will lead to ValidationFailure being raised.

Calling the GitHub API

As well as receiving webhook events in response to actions occurring on GitHub, you can use the GitHub API to make calls to REST endpoints. This library provides support to both construct a request to the GitHub API as well as deciphering the response to a request.

Requests

This module provides functions to help in the construction of a URL request by helping to automate the GitHub-specific aspects of a REST call.

import requests

request_headers = create_headers("brettcannon", oauth_token=auth)
url = "https://api.github.com/repos/brettcannon/gidgethub/issues/1"
response = requests.get(url, headers=request_headers)
gidgethub.sansio.accept_format(*, version="v3", media=None, json=True)

Construct the specification of the format that a request should return. This is used in the accept header field of a request to specify the media type.

The version argument specifies what version of the GitHub API that the request applies to. Typically this only needs to be specified if you are using an API that is in beta.

The media argument along with the json argument specifies what format the response should take. Do note that only some GitHub API endpoints support alternative formats from the default JSON format. For example, if you wanted a comment body to include the rendered HTML then the function call would be accept_format(media="html") to get a media type of application/vnd.github.v3.html+json. If you wanted the diff of a commit then the function call would be accept_format(media="diff", json=False) to get a media type of application/vnd.github.v3.diff.

The default arguments of this function will always return the latest version of the GitHub API with the default response format that this library is designed to support.

gidgethub.sansio.create_headers(requester, *, accept=accept_format(), oauth_token=None)

Create a dict representing GitHub-specific header fields.

The user agent is set according to who the requester is. GitHub asks it be either a username or project name.

The accept argument corresponds to the 'accept' field and defaults to the default result of accept_format(). You should only need to change this value if you are using a different version of the API – e.g. one that is under development – or if you are looking for a different format for the response, e.g. wanting the rendered HTML of a Markdown file.

The oauth_token allows making an authenticated request. This can be important if you need the expanded rate limit provided by an authenticated request.

For consistency, all keys in the returned dict will be lowercased.

Responses

Decipher a response from the GitHub API gather together all of the details that are provided to you. Continuing from the example in the Requests section:

# Assuming `response` contains a requests.Response object.
import datetime


status_code = response.status_code
headers = response.headers
body = response.content
data, rate, more = decipher_response(status_code, headers, body)
# Response details are in `data`.
if more:
    if not rate.remaining:
        now = datetime.datetime.now(datetime.tzinfo.utc)
        wait = rate.reset_datetime - now
        time.sleep(wait.total_seconds())
    response_more = requests.get(more, headers=request_headers)
    # Decipher `response_more` ...
class gidgethub.sansio.RateLimit(*, limit, remaining, reset_epoch)

The rate limit imposed upon the requester.

The reset_epoch argument is expected to be UTC seconds from the epoch.

The boolean value of an instance whether another request can be made. This is determined based on whether there are any remaining requests or if the reset datetime has passed.

limit

The maximum limit of requests per hour the requester can make.

reset_datetime

The datetime.datetime object representing when the requester’s quota is refreshed. The object is timezone-aware to UTC.

gidgethub.sansio.decipher_response(status_code, headers, body)

Decipher an HTTP response for a GitHub API request.

The mapping providing the headers is expected to support lowercase keys.

The parameters of this function correspond to the three main parts of an HTTP response: the status code, headers, and body. Assuming no errors which lead to an exception being raised, a 3-item tuple is returned. The first item is the decoded body (typically a JSON object, but possibly None or a string depending on the content type of the body). The second item is a RateLimit instance based on what the response specified.

The last item of the tuple is the URL where to request the next set of results. If there are no more results then None is returned. Do be aware that the URL can be a URI template and so it may need to be expanded.

If the status code is anything other than 200, 201, or 204, then an appropriate HTTPException is raised.

Utilities

gidgethub.sansio.format_url(url, url_vars)

Construct a URL for the GitHub API.

The URL may be absolute or relative. In the latter case the appropriate domain will be added. This is to help when copying the relative URL directly from the GitHub developer documentation.

The dict provided in url_vars is used in URI template expansion.