added curlable script to cancel circleci workflows

Author: jinal--shah

curl-scripts/cci_cancel_redundant_workflows.sh

@@ -0,0 +1,156 @@
+#!/usr/bin/env bash
+# vim: et sr sw=4 ts=4 smartindent:
+# Cancels redundant PR builds on circleci pipelines.
+# Expected to be run from Github Actions.
+#
+# This only works for PR branches as it relies on
+# env var GITHUB_HEAD_REF which only exists for PRs
+# in github actions.
+#
+# This is by design - generally we don't want to cancel
+# builds of commits on release or main branches as sometimes
+# we need to deploy different commits sequentially rather than
+# bundled. However commits on a PR generally should get squashed
+# as they are all part of the same feature or bugfix and we only
+# need to built the HEAD of it.
+
+REQUIRED_VARS="
+    CIRCLE_TOKEN
+    CCI_ORG_NAME
+    GH_BRANCH
+"
+
+CCI_GITHUB_APP="${CCI_GITHUB_APP:-}" # set to true if you access CircleCi with Github App
+CCI_API="https://circleci.com/api/v2"
+
+# If you access circleci with github app and not oauth
+# set CCI_ORG_NAME to your Circleci org id (see your org settings)
+if [[ -n "$CCI_GITHUB_APP" ]]; then
+    if [[ -z "$CCI_ORG_NAME" ]]; then
+        echo >&2 "ERROR: using CCI_GITHUB_APP: set env var CCI_ORG_NAME to your CircleCI org ID"
+        exit 1
+    fi
+    CCI_VCS_SLUG="circleci"
+else
+    # defaults when using CircleCI oauth, not github app
+    CCI_VCS_SLUG="gh"
+    CCI_ORG_NAME="${GITHUB_REPOSITORY}"
+fi
+
+declare -a WORKFLOWS_TO_CANCEL=()
+
+set_GH_BRANCH() {
+    GH_BRANCH=""
+    case "${GITHUB_EVENT_NAME:-}" in
+      pull_request*) GH_BRANCH="$GITHUB_HEAD_REF" ;;
+      *) GH_BRANCH="$GITHUB_REF_NAME" ;;
+    esac
+
+    if [[ -z "$GH_BRANCH" ]]; then
+        echo >&2 "ERROR: couldn't set GH_BRANCH based on trigger event [${GITHUB_EVENT_NAME:-}]"
+        return 1
+    fi
+
+    export GH_BRANCH
+    return 0
+}
+
+required_vars() {
+    local rc=0
+    local required_vars="$1"
+    local this_var=""
+    for this_var in $required_vars; do
+        if ! check_var_defined $this_var
+        then
+            failed="${failed}\$$this_var "
+            rc=1
+        fi
+    done
+    [[ $rc -ne 0 ]] && echo >&2 "ERROR: following vars must be set in env:\n$failed"
+    return $rc
+}
+
+check_var_defined() { [[ ! -z "${!1}" ]] ; }
+
+pipelines_for_branch() {
+    local o=""
+    o=$(
+        curl -sS --request GET \
+            --url "$CCI_API/project/${CCI_VCS_SLUG}/${CCI_ORG_NAME}/pipeline?branch=$GH_BRANCH" \
+            --header "Circle-Token: ${CIRCLE_TOKEN}" \
+        | jq -r '.items[].id'
+    )
+
+    if [[ $? -ne 0 ]] || [[ -z "${o:-}" ]]; then
+        echo >&2 "ERROR: failed to get pipelines for branch $GH_BRANCH"
+        return 1
+    else
+        echo "$o"
+        return 0
+    fi
+}
+
+cancel_workflows() {
+    local rc=0
+    for id in ${WORKFLOWS_TO_CANCEL[@]}; do
+        echo "INFO: attempting to cancel workflow id $id"
+        curl --request POST \
+            --url "$CCI_API/workflow/$id/cancel" \
+            --header "Circle-Token: ${CIRCLE_TOKEN}" \
+        || rc=1
+    done
+
+    return $rc
+}
+
+workflow_for_pipeline() {
+    local pipeline_id="$1"
+    local o=""
+    o=$(
+        curl -sS --request GET \
+            --url "${CCI_API}/pipeline/${pipeline_id}/workflow" \
+            --header "Circle-Token: ${CIRCLE_TOKEN}" \
+        | jq -r '.items[] | select(.status | test("running|failing|on_hold")) | .id'
+    )
+    if [[ $? -ne 0 ]]; then
+        echo >&2 "ERROR: failed to get single workflow for pipeline $pipeline_id"
+        return 1
+    else
+        echo "$o"
+        return 0
+    fi
+}
+
+main() {
+    set_GH_BRANCH || return 1
+    required_vars "$REQUIRED_VARS" || return 1
+
+    echo "INFO: Getting pipelines for branch $GH_BRANCH"
+    pipeline_ids=$(pipelines_for_branch) || return 1
+
+    local rc=0
+    for pipeline_id in $pipeline_ids; do
+        ! workflow_id=$(workflow_for_pipeline "$pipeline_id") && rc=1 && continue
+        [[ -n "$workflow_id" ]] && WORKFLOWS_TO_CANCEL+=("$workflow_id")
+    done
+
+    if [[ ${#WORKFLOWS_TO_CANCEL[@]} -lt 1 ]]; then
+        echo "INFO: found no active workflows to cancel."
+        return 0
+    fi
+
+    echo "INFO: will cancel these workflow ids:" ${WORKFLOWS_TO_CANCEL[*]}
+    if cancel_workflows
+    then
+        echo "INFO: all currently running workflows cancelled successfully"
+        return 0
+    else
+        echo "INFO: Didn't kill all workflows successfully."
+        echo "INFO: Please clean them up manually via the circleci dashboard"
+        return 1
+    fi
+
+}
+
+main
+exit 0