[WIP] Automatically cancel old PR end to end builds when a new one is triggered

actions/cancel_old_builds.yaml

@@ -0,0 +1,15 @@
+---
+name: cancel_old_builds_for_pr
+description: Action which looks for old st2_pkg_e2e_test builds for a particular builds and cancel any old / existing build.
+enabled: true
+runner_type: python-script
+entry_point: cancel_old_builds_for_pr.py
+parameters:
+  build_num:
+    type: string
+    description: "Circle CI build number."
+    required: true
+  pr_num:
+    type: string
+    description: "Github pull request number"
+    required: true

actions/cancel_old_builds_for_pr.py

@@ -0,0 +1,94 @@
+import os
+
+from st2common.runners.base_action import Action
+
+from st2client.client import Client
+
+ACTION_REF = 'st2ci.st2_pkg_e2e_test'
+
+
+class CancelOldBuildsForPrAction(Action):
+    def run(self, build_num, pr_num):
+        if not build_num or not pr_num:
+            self.logger.info('Skipping old build cancelation because pr num or build num is not '
+                             'set')
+            return
+
+        build_num = int(build_num)
+        pr_num = int(pr_num)
+
+        # 1. Find any matching executions
+        client = self._get_client()
+
+        execution_apis = client.liveactions.query(action=ACTION_REF, status='running', limit=100,
+                                                  include_attributes='id,status,parameters')
+
+        to_cancel_execution_apis = self._filter_executions(execution_apis,
+                                                           current_build_num=build_num,
+                                                           current_pr_num=pr_num)
+
+        to_cancel_execution_apis = execution_apis
+        self.logger.info('Found "%s" old execution(s) for PR "%s" to be canceled' %
+                         (len(to_cancel_execution_apis), pr_num))
+        # Make sure we exclude current one and not cancel the current / latest one
+
+        # 2. Cancel old ones
+        for execution_api in to_cancel_execution_apis:
+            msg = ('Canceling old execution with id "%s" for PR "%s" (build_num %s < '
+                   'current_build_num %s)' % (execution_api.id, pr_num,
+                                              execution_api.parameters['pr_num'], pr_num))
+            self.logger.info(msg)
+            client.liveactions.delete_by_id(execution_api.id)
+
+            # TODO: We should probably also ensure here that cleanup task is also called..
+
+    def _filter_executions(self, execution_apis, current_build_num, current_pr_num):
+        # Filter the executions and only return old ones
+        result = []
+
+        for execution_api in execution_apis:
+            parameters = execution_api.parameters
+
+            build_num = int(parameters.get('build_num', 0))
+            pr_num = int(parameters.get('pr_num', 0))
+
+            # Additional safety check to make sure we don't cancel current build
+            if build_num == current_build_num:
+                continue
+
+            # Skip executions for other PRs
+            # Builds without pr_num set are not triggered as part of a PR build but via nightly
+            # builds or similar so we also skip those
+            if not pr_num or pr_num != current_pr_num:
+                continue
+
+            # Execution is considered as old if build_num is < current build num
+            if build_num and build_num < current_build_num:
+                result.apend(execution_api)
+
+        return result
+
+    def _get_client(self):
+        base_url, api_url, auth_url = self._get_st2_urls()
+
+        client_kwargs = {
+            'base_url': base_url,
+            'api_url': api_url,
+            'auth_url': auth_url,
+        }
+
+        token = self._get_auth_token()
+        client_kwargs['token'] = token
+
+        return Client(**client_kwargs)
+
+    def _get_st2_urls(self):
+        base_url = None
+        api_url = os.environ.get('ST2_ACTION_API_URL', None)
+        auth_url = os.environ.get('ST2_ACTION_AUTH_URL', None)
+
+        return base_url, api_url, auth_url
+
+    def _get_auth_token(self):
+        token = os.environ.get('ST2_ACTION_AUTH_TOKEN', None)
+        return token

actions/st2_pkg_e2e_test.meta.yaml

@@ -66,6 +66,9 @@ parameters:
   dev_build:
     type: string
     description: Repo name + CircleCI build number ('st2/3126') to install artifacts from. Overrides version.
+  pr_num:
+    type: string
+    description: Github pull request number.
   initial_commit:
     type: string
     description: Git hash of an initial commit from st2 repo. If provided, the workflow will update status of this commit.

actions/workflows/st2_pkg_e2e_test.yaml

@@ -16,6 +16,7 @@ input:
   - release
   - version
   - dev_build
+  - pr_num
   - initial_commit
   - enterprise
   - enterprise_key
@@ -40,7 +41,7 @@ vars:
   - bootstrap_script_arg_dev_or_ver: <%
       switch(
         ctx().dev_build => "dev=" + ctx().dev_build,
-        not ctx().dev_build => "version=" + coalesce(ctx().version, '')) %> 
+        not ctx().dev_build => "version=" + coalesce(ctx().version, '')) %>
   - st2_username: st2admin
   - st2_password: Ch@ngeMe
   - github_status_org: StackStorm
@@ -67,7 +68,11 @@ tasks:
     next:
       - when: <% ctx().initial_commit != null %>
         do: set_github_status_pending
-      - when: <% ctx().initial_commit = null %>
+      # NOTE: We skip cancelation of old builds for executions which are not triggered as part of
+      # PR builds (e.g. nightly package builds)
+      - when: <% ctx().initial_commit = null and ctx().pr_num %>
+        do: cancel_old_builds_for_pr
+      - when: <% ctx().initial_commit = null and not ctx().pr_num %>
         do: create_vm
   set_github_status_pending:
     action: github.add_status
@@ -80,9 +85,21 @@ tasks:
       description: E2E tests are running...
       target_url: <% ctx().github_status_url %>
     next:
-      - when: <% succeeded() %>
+      # NOTE: We skip cancelation of old builds for executions which are not triggered as part of
+      # PR builds (e.g. nightly package builds)
+      - when: <% succeeded() and ctx().pr_num %>
+        do: cancel_old_builds_for_pr
+      - when: <% succeeded() and not ctx().pr_num  %>
         do: create_vm
 
+  cancel_old_builds_for_pr:
+    action: st2ci.cancel_old_builds_for_pr
+    input:
+      build_num: <% ctx().dev_build %>
+      pr_num: <% ctx().pr_num %>
+    next:
+      - do:
+        - create_vm
   create_vm:
     action: st2cd.create_vm_role
     input:

rules/st2_pkg_e2e_test_centos7_on_st2_pr.yaml

@@ -42,6 +42,7 @@ action:
         pkg_env: staging
         release: unstable
         dev_build: "st2/{{trigger.body.payload.build_num}}"
+        pr_num: {{trigger.body.payload.pull_requests[0].url.split('/')[-1]}}
         initial_commit: "{{trigger.body.payload.vcs_revision}}"
         triggering_commit_url: |
           COMMITTER: {{trigger.body.payload.author_name}}