AWS remove files in S3 using CodeBuild in CodePipeline - amazon-web-services

Question

How can I remove unwanted files in an S3 bucket as the output of a pipeline in CodePipeline, using CodeBuild's buildspec.yml file?
For example:
The build folder of a GitHub repo is put in the designated S3 bucket so the bucket can be used as a static website.
I pushed a file earlier to the bucket which I don't need anymore. How do I use the buildspec.yml file to "clean" the bucket before pushing the artifacts of my pipeline to the bucket?
An example buildspec.yml file:
version: 0.2
phases:
build:
commands:
- mkdir build-output
- find . -type d -name public -exec cp -R {} build-output \;
- find . -mindepth 1 -name build-output -prune -o -exec rm -rf {} +
post_build:
commands:
- mv build-output/**/* ./
- mv build-output/* ./
- rm -R build-output
artifacts:
files:
- '**/*'
Should the command:
rm -rf *
in build phase like this?
build:
commands:
- aws s3 rm s3://mybucket/ --recursive
And how do I reference the right bucket instead of hardcoding the name in the file?

Answer 1

To delete the files in the S3 bucket, you can use the aws s3 rm --recursive command as you already alluded to.
You can pass in the bucket name from the pipeline to CodeBuild by setting it in the environment variable.
ArtifactsBucket:
Type: AWS::S3::Bucket
Properties:
BucketName: my-artifacts
CodeBuildProject:
Type: AWS::CodeBuild::Project
Properties:
Environment:
EnvironmentVariables:
- Name: ARTIFACTS_BUCKET
Value: !Ref ArtifactsBucket
Type: PLAINTEXT
In the buildspec, you can then refer to the ARTIFACTS_BUCKET env var, for example:
build:
commands:
- aws s3 rm --recursive "s3://${ARTIFACTS_BUCKET}/"
An alternative approach you could take is to declare lifecycle management on the bucket. For example, you can say "delete all objects after 30 days" like so:
ArtifactsBucket:
Type: AWS::S3::Bucket
Properties:
BucketName: my-artifacts
LifecycleConfiguration:
Rules:
- ExpirationInDays: 30
Id: Expire objects in 30 days
Status: Enabled