Matt Chung's Site

Author: mattchung

  • Implementing Licenses API for github3.py

    I came across this license issue while searching on GitHub. So, I thought I’d give it a shot. I pinged sigmavirus24 in #github3.py seeing if this was a feature I could implement. He gave the thumbs up and I was off.

    Testing manually first

    Before any implementation, I always like to get a better understanding of the API by using good ol’ fashion curl.

    curl https://api.github.com/licenses \
-H "Accept: application/vnd.github.drax-preview+json"

    Sending a custom Accept: Header

    In the code base, most classes inherit from github3.GitHubCore, which inherits from requests.Session. We can pass in**kwargs, and requests.Session.get accepts a headers as a kwarg. So, we can pass a custom Accept: header like so:

    headers = {
    'Accepts': 'application/vnd.github.drax-preview+json'
}

url = self._build_url('license')
json = self._json(self._get(url, headers=headers))

    How to add attributes to License model

    By default, the model will not expose any attributes. How do we do that? The key is implementing __update_attributesmethod.

    github3.licenses.License inherits from github3.models.GitHubObject, which calls __update_attriubtes in its__init__.

    class GitHubObject(object):
    """The :class:`GitHubObject <GitHubObject>` object. A basic class to be
    subclassed by GitHubCore and other classes that would otherwise subclass
    object."""
    def __init__(self, json):
        super(GitHubObject, self).__init__()
        if json is not None:
            self.etag = json.pop('ETag', None)
            self.last_modified = json.pop('Last-Modified', None)
            self._uniq = json.get('url', None)
        self._json_data = json
        self._update_attributes(json)

    So, let’s add License attributes

    def _update_attributes(self, license):
    self.name = license.get('name')
    self.permitted = license.get('permitted')
    self.category = license.get('category')
    self.forbidden = license.get('forbidden')
    self.featured = license.get('featured')
    self.html_url = license.get('html_url')
    self.body = license.get('body')
    self.key = license.get('key')
    self.description = license.get('description')
    self.implementation = license.get('implementation')
    self.required = license.get('required')

    Writing test

    This guide is a great place to start. But, just a few pointers. For unit tests, copy/paste example data the API docs. For example, grab the JSON data from the license documentation. Save it under tests/unit/.

    For integration tests, you’ll need to perform HTTP request(s). The betamax wrapper will record it to tests/cassettes.

    Summary

    This feature was merged in this pull request. I really enjoy contributing to this project. Primarily since sigmavirus24 is a pleasure to work with and extremely helpful. He’s super patient and I appreciate he takes the time onboarding new contributors.

  • Contributing to github3.py

    sigmavirus24 tweetI’ve always been scared of open sourcing, despite wanting to get involved for a long time? Why?

    For a long time, I’ve programmed in isolation. But, I did enjoy it. Unfortunately, this leaves little (to none) opportunity for feedback and critism. Afraid of rejection? Afraid of not appearing as smart as I think I am ?

    Serepdentiosuly, I came across this post on reddit post. His comment looked warm and welcoming. Let’s give it a shot again.

    I received an e-mail from @sigmavirus24. Looks like he could use some help moving existings tests under tests/* to tests/unit and tests/integration. This is a great way to get familiar with the code base. I’m game.

    @sigmavirus24 posted this tweet. I was so happy and I hugged Jessica, who was sitting next to me when I saw it pop up on my feed. I didn’t anticipate it and it is what makes me enjoy working on F/OSS.

    I Was on IRC and dropped a note to @sigmavirus24 about implementing this new API feature. I think I’ll tackle this in parallel with migrating tests over.

  • Mocking boto exception

    I was getting so frustrated.

    I knew how to raise the exception with side_effect=. But, how do you mock the exception?

    try:
    connection = connect_to_sqs
except BotoServerError as m:
    if m.error_code == "AlreadyExistsException"

    To get it to work, I inherited the exception class – BotoServerError

    from boto.exceptions import BotoServerError

class MockBotoServerError(BotoServerError):
    def __init__(self, error_code)
        self.error_code = error_code

@mock.patch('cloudwhale.build.connect_to_sqs', side_effect=MockBotoServerError())

    Order of decorator

    Also, pay attention to the order of parameters. My assertions were failing left and right.