feat: Continuous delivery github actions

[asoorm]

Feature: Automatically build and publish latest & tag version bump versions based on SemVer
  In order for tyk-operator users to track latest or pin to a specific version of the operator
  As an operator developer
  When I merge to master
    I need to automatically tag the git repo as `latest` & bump the version
    And I need to publish a changelog and add that to the release notes in GitHub
    And the latest and versioned tag need to be pushed to DockerHub

  Scenario: Merge a pull request tagging
    Given I have a pull request
    When i merge to master
    Then github actions should automatically tag the master as latest
      And github actions should automatically bump the minor version `X.MINOR.X`

  Scenario: Merge a pull request with commit "#patch"
    Given I have a pull request
      And there is a commit message containing "#patch"
    When i merge to master
    Then github actions should automatically tag the master as latest
      And github actions should automatically bump the patch version "X.X.PATCH"

  Scenario: Merge a pull request with commit "#major"
    Given I have a pull request
      And there is a commit message containing "#major"
    When i merge to master
    Then github actions should automatically tag the master as latest
      And github actions should automatically bump the patch version "MAJOR.X.X"

--- DONE, But needs validation

  Scenario: Auto publish release notes
    Given I have a pull request
    When a release is tagged (latest or semver)
    Then A changelog will be generated from all the commits between this and the previous "latest" tag
      And this changelog will be published as release notes against the tag

  Scenario: Build and Publish to DockerHub
    Given I have a github repository
    When a release is tagged (latest or semver)
    Then github actions should build a docker image and push it to dockerhub
      And the docker image that has been pushed should have 2 tags; latest and the new github semver tag

[alephnull]

I'll take a stab at implementing this using goreleaser. Might have to tweak the commit tags to make it work.

[asoorm]

Thanks @alephnull - Just FYI - I've implemented basic goreleaser to build using Dockerfile, but it only builds when I push a tag manually.

If you could just validate my setup, and Maybe this is OK as per our discussions for time being.

[alephnull]

@asoorm The goreleaser stuff looks great.

Feature: Automatically build and publish latest & tag version bump versions based on SemVer Scenario: Merge a pull request with commit "#patch" [&c]

This is partially addressed. When the semver policy is established, we can stop having to tag versions by hand. I propose a policy based on branches like the rest of tyk. This is an attempt to work with current branching strategies that developers are familiar with and move to a state where we do not have to tag versions by hand.

• we start at "ABI" version 1, this version does not increment automatically. This version is bumped only when we breaking the "binary" interface or introducing an incompatible change. This is always done by hand. This corresponds to MAJOR in semver terminology.
• master is the development branch that all branches have as a common ancestor
• branch v1.1 corresponds to major release v1.1 and so on
• every commit on branch v1.1 bumps PATCH
• any commit on a vx.y branch that has a title that matches the regexp ^#minor: .* bumps MINOR (y), resetting PATCH to 0
• all versions are maintained as tags on that branch, by using git describe --tags in automation

Questions like

• should commits to release branches transit master
• where to "cut a release branch" from
• where should CI kick in
• where should CD kick in are left to repo owners.

Scenario: Auto publish release notes

Should be easy to generate changelog and release notes when the semver policy is established.

Scenario: Build and Publish to DockerHub

I think this is done. For now at least.

[asoorm]

Thanks @alephnull closing & marking as Done.