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Prithvi Jethwa
Prithvi Jethwa

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Parse UserParameters sent from AWS CodePipeline to AWS Lambda in Go

#aws #go #awscodepipeline #awslambda

Context

I was trying to setup the UserParameters configuration within the AWS CodePipeline Template being generated,

Name: ... Actions: - Name: Invoke-Lambda ActionTypeId: Category: Invoke Owner: AWS Provider: Lambda Version: '1' Configuration: FunctionName: exampleLambdaFunction UserParameters: '{"example":"user-parameters"}'
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While testing it out on an AWS Lambda, written in Go, it took a bit longer than usual to find out the Function Definition for the Handler, to parse the AWS CodePipeline JSON Event that would be sent, For Example:

{ "CodePipeline.job": { "id": "11111111-abcd-1111-abcd-111111abcdef", "accountId": "111111111111", "data": { "actionConfiguration": { "configuration": { "FunctionName": "exampleLambdaFunction", "UserParameters": "{\"example\":\"user-parameters\"}" } }, "inputArtifacts": [ ... ], ... } } }
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Solution

Use the github.com/aws/aws-lambda-go/events package link which contains the events.CodePipelineJobEvent that helps unmarshal the AWS CodePipeline JSON event being sent

package main import ( "context" "fmt" "github.com/aws/aws-lambda-go/events" "github.com/aws/aws-lambda-go/lambda" ) func Handler(ctx context.Context, event events.CodePipelineJobEvent) (string, error) { fmt.Printf("received codepipeline event function name: %+v\n", event.CodePipelineJob.Data.ActionConfiguration.Configuration.FunctionName) fmt.Printf("received codepipeline event user parameters: %+v\n", event.CodePipelineJob.Data.ActionConfiguration.Configuration.UserParameters) return "cool", nil } func main() { lambda.Start(Handler) }
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References

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