Add Application to Pipeline

Create Stage #

At this point, you have a fully operating CDK pipeline that will automatically update itself on every commit, BUT at the moment, that is all it does. We need to add a stage to the pipeline that will deploy our application.

Create a new file in cdk_workshop called pipeline_stage.py with the code below:

from constructs import Construct
from aws_cdk import (
    Stage
)
from .cdk_workshop_stack import CdkWorkshopStack

class WorkshopPipelineStage(Stage):

    def __init__(self, scope: Construct, id: str, **kwargs):
        super().__init__(scope, id, **kwargs)

        service = CdkWorkshopStack(self, 'WebService')

All this does is declare a new core.Stage (component of a pipeline), and in that stage instantiate our application stack.

Add stage to pipeline #

Now we must add the stage to the pipeline by adding the following code to cdk_workshop/pipeline_stack.py:

from constructs import Construct
from aws_cdk import (
    Stack,
    aws_codecommit as codecommit,
    pipelines as pipelines,
)
from cdk_workshop.pipeline_stage import WorkshopPipelineStage

class WorkshopPipelineStack(Stack):
    def __init__(self, scope: Construct, id: str, **kwargs) -> None:
        super().__init__(scope, id, **kwargs)

        # Creates a CodeCommit repository called 'WorkshopRepo'
        repo = codecommit.Repository(
            self, "WorkshopRepo", repository_name="WorkshopRepo"
        )

        pipeline = pipelines.CodePipeline(
            self,
            "Pipeline",
            synth=pipelines.ShellStep(
                "Synth",
                input=pipelines.CodePipelineSource.code_commit(repo, "main"),
                commands=[
                    "npm install -g aws-cdk",  # Installs the cdk cli on Codebuild
                    "pip install -r requirements.txt",  # Instructs Codebuild to install required packages
                    "npx cdk synth",
                ]
            ),
        )

        deploy = WorkshopPipelineStage(self, "Deploy")
        deploy_stage = pipeline.add_stage(deploy)

This imports and creates an instance of the WorkshopPipelineStage. Later, you might instantiate this stage multiple times (e.g. you want a Production deployment and a separate development/test deployment).

Then we add that stage to our pipeline (pipeline.add_stage(deploy);). A Stage in a CDK pipeline represents a set of one or more CDK Stacks that should be deployed together, to a particular environment.

Commit/Deploy #

Now that we have added the code to deploy our application, all that’s left is to commit and push those changes to the repo.

git add .
git commit -m "Add deploy stage to pipeline" && git push

Once that is done, we can go back to the CodePipeline console and take a look as the pipeline runs (this may take a while).

Success!