The canonical S3 event image watermarking #serverless application. This application shows how you can use Sparta to:
- Provision a Lambda function and an API Gateway
- Configure S3 event listeners
- Provision an API Gateway that returns pre-signed S3 URLs for public download.
- Access the transformed image
S3_BUCKET=<S3_BUCKET_TO_USE_FOR_CODE_ARTIFACTS> SPARTA_S3_TEST_BUCKET=<S3_BUCKET_TO_USE_AS_EVENT_SOURCE> go run main.go provision --s3Bucket ${S3_BUCKET}
INFO[0000] ========================================
INFO[0000] Welcome to SpartaImager GoVersion=go1.8.3 LinkFlags= Option=provision SpartaVersion=0.12.0 UTC="2017-06-11T17:47:59Z"
INFO[0000] ========================================
INFO[0000] Provisioning service BuildID=f1cfa7da8c30f189ce43320299da619410c0001c CodePipelineTrigger= InPlaceUpdates=false NOOP=false Tags=
INFO[0000] Verifying IAM Lambda execution roles
INFO[0000] IAM roles verified Count=2
INFO[0000] Checking S3 versioning Bucket=sparta-code-bucket VersioningEnabled=true
INFO[0000] Running `go generate`
...
INFO[0054] Waiting for CloudFormation operation to complete
INFO[0068] Stack output Description="API Gateway URL" Key=APIGatewayURL Value="https://hxkf6p61r7.execute-api.us-west-2.amazonaws.com/v1"
INFO[0068] Stack provisioned CreationTime=2017-06-11 16:44:50.619 +0000 UTC StackId="arn:aws:cloudformation:us-west-2:123412341234:stack/SpartaImager/496cf250-4ec5-11e7-88ca-50a686fc379a" StackName=SpartaImager
To upload a file, use the S3 command line tool (or equivalent):
SPARTA_S3_TEST_BUCKET=<S3_BUCKET_TO_USE_AS_EVENT_SOURCE> aws s3 cp ./site/ben.jpg s3://<S3_BUCKET_TO_USE_AS_EVENT_SOURCE>/ben.jpgUsing the APIGatewayURL output referenced above, fetch information about the transformed item via the /info path. The transformed item name is the original filename with a xformed_ prefix: ben.jpg ==> xformed_ben.jpg
Provide the following query arguments to the /info resource:
- bucketName : The name of the S3 bucket (
SPARTA_S3_TEST_BUCKETvalue above) - keyName : The name of the file to return metadata about. Eg:
xformed_ben.jpg
curl "https://hxkf6p61r7.execute-api.us-west-2.amazonaws.com/v1/info?bucketName=<S3_BUCKET_TO_USE_AS_EVENT_SOURCE>&keyName=xformed_ben.jpg" | python -m json.toolOr if you have jq installed:
curl "https://hxkf6p61r7.execute-api.us-west-2.amazonaws.com/v1/info?bucketName=<S3_BUCKET_TO_USE_AS_EVENT_SOURCE>&keyName=xformed_ben.jpg" | jq .{
"S3": {
"AcceptRanges": "bytes",
"Body": {},
"CacheControl": null,
"ContentDisposition": null,
"ContentEncoding": null,
"ContentLanguage": null,
"ContentLength": 407954,
"ContentRange": null,
"ContentType": "image/jpeg",
"DeleteMarker": null,
"ETag": "\"9bb993ee2060ffeb0b752f9a345c04ec\"",
"Expiration": null,
"Expires": null,
"LastModified": "2017-06-11T18:04:16Z",
"Metadata": {},
"MissingMeta": null,
"PartsCount": null,
"ReplicationStatus": null,
"RequestCharged": null,
"Restore": null,
"SSECustomerAlgorithm": null,
"SSECustomerKeyMD5": null,
"SSEKMSKeyId": null,
"ServerSideEncryption": null,
"StorageClass": null,
"TagCount": null,
"VersionId": null,
"WebsiteRedirectLocation": null
},
"URL": "https://<S3_BUCKET_TO_USE_AS_EVENT_SOURCE>.s3-us-west-2.amazonaws.com/ben.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAIRNCZ7DRLEX3NIRA%2F20170611%2Fus-west-2%2Fs3%2Faws4_request&X-Amz-Date=20170611T181726Z&X-Amz-Expires=300&X-Amz-Security-Token=FQoDYXdzEKr%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaDNhDlEZvt8tXPoW%2BLSKZAj5EqEvplV5qlyzPe%2FFtFXy%2B9PhYbD%2FbXNYVjiFsUg4v7ivSbqz3%2FMxeFigMXCaYzgxoCk%2B26urq0ehgrERiT3JnKnmmtbthQlYp4c4lL9Bm3M8K8xDMBc%2F8XSe6b5LcCX6ZQ1Vh2sago0hPdRc4QSqdhMbpiUGssfSS4i3RdgUHhh4oQ9sPutKxp9yBCU1GDREdKsoOuURBSEWjKOo5SgV9MvRVHap8Y8ex1Iau3W0VXLaUPy4nLvHorZ0MpASPZyLaiBlTMea0IHreg9wUX4IekA5EcrsbhLkMUBF4aueT2KIZ4MfdSOAbof9oSik3mnFD5M75aAkk3iya7kWwYmy3hqqrt7b%2BAZWUhCqv5JYXhvkM1PAm4SEKKOXx9ckF&X-Amz-SignedHeaders=host&X-Amz-Signature=51a5d9a7fa1fd8ce16a0cbbc0913a4e87f58b105920f312227097b21ef910e15"
}NOTE : The presigned URL will expire after 5 minutes.
Finally, using the URL value returned in the JSON response, download the transformed item:
curl "https://<S3_BUCKET_TO_USE_AS_EVENT_SOURCE>.s3-us-west-2.amazonaws.com/ben.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAIRNCZ7DRLEX3NIRA%2F20170611%2Fus-west-2%2Fs3%2Faws4_request&X-Amz-Date=20170611T181726Z&X-Amz-Expires=300&X-Amz-Security-Token=FQoDYXdzEKr%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaDNhDlEZvt8tXPoW%2BLSKZAj5EqEvplV5qlyzPe%2FFtFXy%2B9PhYbD%2FbXNYVjiFsUg4v7ivSbqz3%2FMxeFigMXCaYzgxoCk%2B26urq0ehgrERiT3JnKnmmtbthQlYp4c4lL9Bm3M8K8xDMBc%2F8XSe6b5LcCX6ZQ1Vh2sago0hPdRc4QSqdhMbpiUGssfSS4i3RdgUHhh4oQ9sPutKxp9yBCU1GDREdKsoOuURBSEWjKOo5SgV9MvRVHap8Y8ex1Iau3W0VXLaUPy4nLvHorZ0MpASPZyLaiBlTMea0IHreg9wUX4IekA5EcrsbhLkMUBF4aueT2KIZ4MfdSOAbof9oSik3mnFD5M75aAkk3iya7kWwYmy3hqqrt7b%2BAZWUhCqv5JYXhvkM1PAm4SEKKOXx9ckF&X-Amz-SignedHeaders=host&X-Amz-Signature=51a5d9a7fa1fd8ce16a0cbbc0913a4e87f58b105920f312227097b21ef910e15" > xformed_ben.jpg