Cloud formation lambda not picking jar from code build - aws-lambda

Question

I tried to use Code Pipeline to automate the code deployment. It uses Git Hub -> Code Build -> Cloud Formation as mentioned in wiki
AWS Automation of Lambda
I managed to get the pipeline run after few changes suggested by this thread
However whenever I am using the code pipeline, the Lambda test fails saying the class is not found.
In order to verify, I uploaded the jar directly in AWS lambda console and it worked fine.
I also verified the jar which is built by aws code build in the S3 "MyAppBuild" folder and it contains jar file in target/app-1.0-SNAPSHOT.jar in a zip file along with my SamTemplate.yml.
This is the SamTemplate.yml
AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: Outputs the time
Parameters:
SourceBucket:
Type: String
Description: S3 bucket name for the CodeBuild artifact
SourceArtifact:
Type: String
Description: S3 object key for the CodeBuild artifact
Resources:
TimeFunction:
Type: AWS::Serverless::Function
Properties:
Handler: com.xxx.Hello::handleRequest
Runtime: java8
CodeUri:
Bucket: !Ref SourceBucket
Key: !Ref SourceArtifact
Events:
MyTimeApi:
Type: Api
Properties:
Path: /TimeResource
Method: GET
Here is the buildSpec.yaml
version: 0.2
phases:
build:
commands:
- echo Build started on `date`
- mvn test
post_build:
commands:
- echo Build completed on `date`
- mvn package
install:
commands:
- aws cloudformation package --template-file SamTemplate.yaml --s3-bucket codepipeline-us-east-1-xxxx
--output-template-file NewSamTemplate.yaml
artifacts:
type: zip
files:
- SamTemplate.yaml
- target/app-1.0-SNAPSHOT.jar
Any suggestions to try on?
I use maven.

Answer 1

Finally, after a few tries I found a probable solution for the packaging with aws code build, cloud formation, and lambda.
The whole point is that code build creates a wrapper zip of all files mentioned in artifacts:
This is the same zip file which must be given to aws lambda.
In order for aws lambda to accept a zip as valid, classes should be root folder, dependent libs should be in libs folder.
So I managed to do this as my build spec.
version: 0.2
phases:
install:
commands:
- aws cloudformation package --template-file SamTemplate.yaml --s3-bucket codepipeline-us-east-1-XXXXXXXX
--output-template-file NewSamTemplate.yaml
build:
commands:
- echo Build started on `date`
- gradle build clean
- gradle test
post_build:
commands:
- echo Build started on `date`
- gradle build
- mkdir -p deploy
- cp -r build/classes/main/* deploy/
- cp NewSamTemplate.yaml deploy/
- cp -r build/libs deploy/
- ls -ltr deploy
- ls -ltr build
- echo Build completed on `date`
- echo Build is complete
artifacts:
type : zip
files:
- '**/*'
base-directory : 'deploy'