GitHub Action support

I’d like to make semantic-release work within GitHub actions out of the box

action "npx semantic-release" {
  uses = "docker://timbru31/node-alpine-git"
  runs = "npx"
  args = "semantic-release"
  secrets = ["GITHUB_TOKEN", "NPM_TOKEN"]
}

The NPM_TOKEN needs to be configured, but GITHUB_TOKEN should work with the one provided by GitHub action.

But when I run the action, I get the following error

EGHNOPERMISSION The GitHub token doesn’t allow to push on the repository octokit/routes

The problem is that the token is not an OAuth token, but an GitHub App installation access token, because that’s how it’s implemented I assume.

The verification works by checking the respone of github.repos.get() which for the GitHub Action returns

...
  "permissions": {
    "admin": false,
    "push": false,
    "pull": false
  },

Although the token has code write permission to the repository.

The token itself is easily distinguished: it starts with v1., e.g. v1.1234567890123456789012345678901234567890.

We could also just check if process.env.GITHUB_ACTION is set, see Environment variables. But people can pass their own tokens so that’s not guaranteed.

I’d suggest we check for both.

If both is true, we can just assume that it has write access.

I’ll do some testing myself

[pvdlg]

Ok. Checking isNil(env.GITHUB_ACTION) seems better than checking for v1 in the token. I’m guessing GitHub can change the format of token anytime (at some point it will be come v2 I imagine).

[gr2m]

You need to set the GITHUB_TOKEN environment variable from secrets.GITHUB_TOKEN. See https://github.com/octokit/core.js/blob/master/.github/workflows/release.yml for reference