Skip to content

04_DeployingOurFunction.md

Latest commit

 

History

History
70 lines (49 loc) · 2.5 KB

04_DeployingOurFunction.md

File metadata and controls

70 lines (49 loc) · 2.5 KB

Step 3: Deploying to AWS Lambda

(Full source code: step3 directory)

Deploying with SAM CLI

SAM CLI takes care of building, packaging, uploading and deploying the function for us.

But it does need to ask a few questions the first time you deploy the function.

For this tutorial, we only deviate from the defaults for the Stack Name (hello-app ➊) and for the confirmation that it is okay for HelloWorldFunction to not have any authorization defined (Is this okay? [y/N]: y ➋). The function only returns a string, and does not call any AWS API on the server side, so authorization is not needed.

$ sam build
$ sam deploy --guided

Configuring SAM deploy
======================

	Looking for samconfig.toml :  Not found

	Setting default arguments for 'sam deploy'
	=========================================
	Stack Name [sam-app]: hello-app ➊
	AWS Region [us-east-1]:
	#Shows you resources changes to be deployed and require a 'Y' to initiate deploy
	Confirm changes before deploy [y/N]:
	#SAM needs permission to be able to create roles to connect to the resources in your template
	Allow SAM CLI IAM role creation [Y/n]:
	HelloWorldFunction may not have authorization defined, Is this okay? [y/N]: y ➋
	Save arguments to samconfig.toml [Y/n]:

...
Successfully created/updated stack - hello-app in us-east-1

If you get the final Successfully created/updated stack message, then the function is now deployed.

Determining the API URL

Unfortunately, SAM CLI does not show the URL of the HTTP endpoint as part of the sam deploy command output. So we need to execute a couple AWS CLI commands to find that out. In the same terminal, run:

$ region=us-east-1 # use the same region as in the sam deploy command
$ apiId=$(aws cloudformation describe-stack-resource \
  --stack-name hello-app \
  --logical-resource-id ServerlessHttpApi \
  --query StackResourceDetail.PhysicalResourceId \
  --region "${region}" --output text)
$ apiUrl=$(printf "https://%s.execute-api.%s.amazonaws.com" $apiId $region)

Past this point, $apiUrl contains the API's invocation URL.

Calling the API

Let us now invoke the deployed function, to verify that it is working:

$ echo $(curl -s $apiUrl/helloworld)
Hello World!

Congratulations, you've now successfully deployed your first HttpMaid function to AWS!

Next, we'll deploy a change to our function.

←   Overview   →