Artifact-based deployments

src/commands/download-artifact.yml

@@ -0,0 +1,18 @@
+description: Download an artifact from a previous build job
+parameters:
+  path:
+    type: string
+  build-job-name:
+    type: string
+    description: |
+      This must be set to the name of the job that built the artifact we would
+      like to use in subsequent steps.
+steps:
+  - run:
+      name: Query CircleCI API for artifacts from the current build
+      command: |
+        BUILD_JOB_NUMBER=`curl -H "Circle-Token: ${CIRCLE_TOKEN}" https://circleci.com/api/v2/workflow/${CIRCLE_WORKFLOW_ID}/job | jq '.items[] | select( .name == "<<parameters.build-job-name>>" ) | .job_number '`
+        echo "Build job number: ${BUILD_JOB_NUMBER}"
+        ARTIFACT_URL=`curl -H "Circle-Token: ${CIRCLE_TOKEN}" https://circleci.com/api/v2/project/gh/${CIRCLE_PROJECT_USERNAME}/${CIRCLE_PROJECT_REPONAME}/${BUILD_JOB_NUMBER}/artifacts | jq -r ' .items[0].url '`
+        echo "Downloading artifact from URL: ${ARTIFACT_URL}"
+        cd <<parameters.path>>/ && wget --header="Circle-Token: ${CIRCLE_TOKEN}" ${ARTIFACT_URL}

src/jobs/deploy.yml

@@ -52,11 +52,47 @@ parameters:
   user-deploy:
     type: boolean
     default: false
+  attach-workspace:
+    default: true
+    description: |
+      Boolean for whether or not to attach to an existing workspace. Default is
+      true.
+
+      If you have too many deploy jobs gated by a manual approval step, you
+      might end up with very slow deploy jobs due to CircleCI attaching every
+      single pre-existing workspace within the workflow prior to the approval
+      step.
+    type: boolean
+  use-artifacts:
+    type: boolean
+    default: false
+    description: |
+      You can instruct the deploy job to use an existing artifact from a
+      previous build job instead of creating a new one from scratch using
+      Terraform's Lambda module.
+
+      Please note that the CIRCLE_TOKEN environment variable must be set for
+      this to work properly.
+  build-job-name:
+    type: string
+    default: build-job-name
+    description: |
+      This must be set to the name of the job that built the artifact we would
+      like to deploy in this job.
 executor: << parameters.executor >>
 steps:
   - checkout
-  - attach_workspace:
-      at: /home/circleci
+  - when:
+      condition: <<parameters.attach-workspace>>
+      steps:
+        - attach_workspace:
+            at: /home/circleci
+  - when:
+      condition: <<parameters.use-artifacts>>
+      steps:
+        - download-artifact:
+            path: <<parameters.path>>
+            build-job-name: <<parameters.build-job-name>>
   - when:
       condition: <<parameters.fleece-run-to-env>>
       steps:

src/jobs/sam-build.yml

@@ -44,6 +44,18 @@ parameters:
     default: src/
     description: >
       The relative difference between workspace-root and the working directory
+  template-resource-name:
+    type: string
+    default: LambdaFunction
+    description: >
+      Tha logical name under which the function to be built can be found.
+      It is used to construct the path to the SAM build artifacts in order
+      to generate the Lambda ZIP file.
+  store-artifact:
+    default: false
+    description: |
+      Store the build file as a job artifact?
+    type: boolean
 # In order to use "sam build --use-container" we need to use
 # a VM executor with docker installed locally.
 executor: <<parameters.executor>>
@@ -62,6 +74,16 @@ steps:
   - run: pip install aws-sam-cli
   - sam-build:
       path: << parameters.path >>
+  - when:
+      condition: <<parameters.store-artifact>>
+      steps:
+        - run:
+            name: Create ZIP file for Lambda function
+            command: zip -r <<parameters.workspace-root>><<parameters.template-resource-name>>.zip .
+            working_directory: <<parameters.workspace-root>><<parameters.workspace-root-to-working-directory>><<parameters.path>>/.aws-sam/build/<<parameters.template-resource-name>>/
+        - store_artifacts:
+            path: <<parameters.workspace-root>><<parameters.template-resource-name>>.zip
+            destination: <<parameters.template-resource-name>>.zip
   - when:
       condition: <<parameters.persist-to-workspace>>
       steps: