I have a node CDK project with some python lambdas, I have put some code into the handler of the lambda that i have specified in my stack this being the execute function. I add some gibberish into the start of that function so it would fail or not be valid. I type cdk synth this still generates a template, shouldn't this do some validation on the lambdas, if not how do we validate these lambdas before deploying?
Thanks
From the AWS documentation:
The Toolkit provides the ability to convert one or more AWS CDK stacks
to AWS CloudFormation templates and related assets (a process called
synthesis) and to deploy your stacks to an AWS account.
The cdk synth does not do any additional validation on the underlying Cloudformation resources -- it simply converts the CDK code into Cloudformation templates.
You have to add in this functionality yourself before deployment. One way to achieve this could be running a local SAM test suite.
Related
TLDR: Is there a way to -- using a single Cloudformation template -- deploy a lambda function with code in S3 or ECR?
Say I have two Lambda functions.
Function A has code in an S3 bucket and relies on a Lambda Layer
Function B is a containerized function with the image in an ECR instance
Here's my deployment setup for the two functions:
function-a/
s3-bucket.template // CFN Stack template for S3 bucket
lambda-function.template // CFN Stack template for lambda function
deploy.sh // Script that creates S3 bucket template,
builds/uploads code,
and creates lambda function stack
function-b/
ecr.template // CFN Stack template for ECR instance
lambda-function.template // CFN Stack template for lambda function
deploy.sh // Script that creates ECR,
builds/uploads docker image,
and creates lambda function stack
Results: 4 Cloudformation stacks, 1 S3 bucket, 1 ECR, 2 Lambda functions
I find this amount of configuration setup for these two functions needlessly complex.
I understand that buckets and registries need to exist. But I don't want to explicitly define/deploy/manage them using extra build steps.
What else I looked at: I checked AWS SAM -- but SAM also doesn't absolve me from managing the code deployment myself. I used AWS CDK which actually abstracts this away. But for certain reasons I don't want to use CDK here atm. I do not want to use the Serverless framework.
I'm disappointed that most of the examples from the documentation of Cloudformation and SAM just end up creating buckets and registries manually. This doesn't seem like a scalable way to handle it for many environments. This isn't Infrastructure-as-Code.
Is there a simpler way?
The S3 bucket and ECR would be reused for future functionality. So I think of it as two shared resources (S3 code bucket and ECR) and then two new resources (the new Lambda functions).
Most likely you'll have a stack of shared items, things are used by everything but don't structurally change that much. Then another stack of application functions, which will likely change more often. Separating these two different types of things is a good idea.
I am trying to understand the correct way to setup my project on AWS so that I ultimately get the possibility to have CI/CD on the lambda functions. And also to ingrain good practices.
My application is quite simple : an API that calls lambda functions based on users' requests.
I have deployed the application using AWS SAM. For that, I used a SAM template that was using local paths to the lambda functions' code and that created the necessary AWS ressources (API Gateway and Lambda). It was necessary to use local paths for the lambda functions because the way SAM works does not allow using existing S3 buckets for S3 events trigger (see here) and I deploy a Lambda function that is watching the S3 bucket to see any updated code to trigger lambda updates.
Now what I have to do is to push my Lambda code on Github. And have a way that Github pushes the lambda functions' code from github to the created S3 bucket during the SAM deploy and the correct prefix. Now what I would like is a way to automatically to that upon Github push.
What is the preferred way to achieve that ? I could not find clear information in AWS documentation. Also, if you see a clear flaw in my process don't hesitate to point it out.
What you're looking to do is a standard CI/CD pipeline.
The steps of your pipeline will be (more or less): Pull code from GitHub -> Build/Package -> Deploy
You want this pipeline to be triggered upon a push to GitHub, this can be done by setting up a Webhook which will then trigger the pipeline.
Last two steps are supported by SAM which I think you have already implemented before, so will be a matter of triggering the same from the pipeline.
These capabilities are supported by most CI/CD tools, if you want to keep everything in AWS you could use CodePipeline which also supports GitHub integration. Nevertheless, Jenkins is perfectly fine and suitable for your use case as well.
There are a lot of ways you can do it. So would depend eventually on how you decide to do it and what tools you are comfortable with. If you want to use native AWS tools, then Codepipeline is what might be useful.
You can use CDK for that
https://aws.amazon.com/blogs/developer/cdk-pipelines-continuous-delivery-for-aws-cdk-applications/
If you are not familiar with CDK and would prefer cloudformation, then this can get you started.
https://docs.aws.amazon.com/codepipeline/latest/userguide/tutorials-github-gitclone.html
I have to create multiple IAM users from a single cloudformation stack at once.
Since, Cloudformation doesn't support Loop. I have Created a Code Pipeline which deploys cloudformation template stored in AWS CodeCommit.
Can I use Parameter Override Feature of Code Pipeline to Create Multiple Users like giving parameter in list as:
{
"Username":["Bob","Alice","John"]
}
You're going to need an action between the CodeCommit and CloudFormation actions to generate a template that includes each IAM user resource (unless you plan to commit the expanded CloudFormation template). CodeBuild is probably your best bet to run some command that generates the CoudFormation template.
You might find CDK (https://github.com/awslabs/aws-cdk/) interesting for a use case like this. It will let you describe IAM users in a loop and then synthesize a CoudFormation temple. At the time of writing this answer it's in preview, so don't rely on it for production.
You should, but if you don't leave pre-existing ones in, I believe it will drop the previous ones. You could do a Custom resource tied to a Lambda Function, then your Lambda function could "not" drop the previous resources.
I am using CodePipeline to deploy my SAM (lambda etc) application referencing https://docs.aws.amazon.com/lambda/latest/dg/build-pipeline.html.
The "issue" now is my CloudFormation has some parameters inside and CodePipeline requires that I set these. I could do so via parameter overrides
But is this the correct way? I actually only want it set once at the start. And I'd rather have users set it in CloudFormation and CodePipeline should follow those values.
This stack is already created, why isit that CodePipeline complains I need them set?
The input parameters are required by CloudFormation to update.
Template configuration is the recommended way to specify the input parameters. You could create a template file of input parameters for the customers to use.
Possible solution is to create custom Lambda functions which will be invoked from CodePipeline using Invoke action.
As a parameter to such Lambda you would specify CloudFormation stack name. Lambda then will load CloudFormation parameters from existing stack and create output from it (using appropriate AWS SDK). Such artifact will be used as an input to CloudFormation deployment.
Another solution is to create CodeBuild project which will do the same thing.
It's a bit complex but it seems that CodePipeline always needs full set of parameters unfortunately.
We're building an API using AWS SAM. Build on the Lambda Node Template in CodeStar. Things were going well until our template.yml file became too big. Whenever the code is pushed and CloudFormation starts to execute the change set and create a stack for the SAM endpoints, it fails and rolls back to the last successful build.
It seems that we have too many resources that exceeds the CloudFormation limit per stack.
I tried splitting the template file and edited the buildspec to handle two template files and do two AWS CloudFormation package commands and added another artifact. But it didn't work either. As only the first template is recognized and only one stack is created.
I can't find a way to make an automated deployment that creates multiple stacks.
I'd appreciate some input into this and suggestions to handle such a scenario.
Thanks in advance.
You should try using the nested stacks pattern. Instead of splitting your current stack into multiple parallel stacks, you will create a parent stack that will in turn create multiple child stacks.
More information here.
AWS SAM (as of SAM v1.9.0) supports nested applications which map to nested CloudFormation stacks which gets around the 200 resource limit. (AWS::Serverless::Application transforms into a AWS::CloudFormation::Stack)
https://github.com/awslabs/serverless-application-model/releases/tag/v1.9.0
The main subject to see is what is the components you have in your sam template ? is there any dependencies ? is all Functions shares the same API Gateway or not ? is all functions access DynamoDB table ?
In my case, I split the SAM by API [ API Gateway + functions ( CRUD)] in a mono repo way, each folder contains its sam template.
If you have a shared service like Redis, or SNS, SQS, you can have a separate stack with the export import Feature to import the ARN of the service.