Working lambda function with s3 code doesn't work with plugin

[spongenee]

Expected Behavior

running lambda can add datadog wrapper with no issues

Actual Behavior

once I add the plugin, without adding instrumenting code, running lambdas that involve loading content from s3 fails with below error

"errorMessage": "cannot load such file -- aws-sigv4",
  "errorType": "Init<LoadError>"

Functions that do not load s3 files runs with no error.
The s3 code

      s3_object = s3.get_object({bucket: ENV['S3_BUCKET_NAME'], key: '*****'})
      file_contents = s3_object[:body].read
      application_file = YAML.load(file_contents)

Steps to Reproduce the Problem

1. Add below to serverless.yml

+  - serverless-plugin-datadog 
 custom:
+  datadog:
+    site: datadoghq.com
+    apiKeySecretArn: ********

2. deploy and invoke function

Specifications

• Serverless Framework version: 3.22.0
• Datadog Serverless Plugin version: 5.89.0
• Lambda function runtime (Python 3.7, Node 10, etc.): Ruby 3.2.2

Stacktrace

{
"errorMessage": "cannot load such file -- aws-sigv4",
"errorType": "Init<LoadError>",
"stackTrace": [
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:141:in `require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:141:in `rescue in require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:135:in `require'",
  "/var/runtime/ruby/3.2.0/gems/aws-sdk-core-3.219.0/lib/aws-sdk-core.rb:6:in `<top (required)>'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'",
  "/var/runtime/ruby/3.2.0/gems/aws-sdk-kms-1.99.0/lib/aws-sdk-kms.rb:11:in `<top (required)>'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'",
  "/var/runtime/ruby/3.2.0/gems/aws-sdk-s3-1.182.0/lib/aws-sdk-s3.rb:11:in `<top (required)>'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:141:in `require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:141:in `rescue in require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:135:in `require'",
  "/var/task/helpers/s3_helper.rb:1:in `<top (required)>'",
  "/var/task/handlers/base_handlers/pg_handler.rb:11:in `require_relative'",
  "/var/task/handlers/base_handlers/pg_handler.rb:11:in `<top (required)>'",
  "/var/task/handlers/void_charge.rb:1:in `require_relative'",
  "/var/task/handlers/void_charge.rb:1:in `<top (required)>'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'",
  "<internal:/var/lang/lib/ruby/site_ruby/3.2.0/rubygems/core_ext/kernel_require.rb>:136:in `require'"
]
}

[lym953]

@duncanista Any idea? This code might be relevant: https://github.com/DataDog/datadog-lambda-rb/blame/main/Dockerfile#L20-L21 I have no idea how it works though.

[duncanista]

Hey @spongenee!

Thanks for tagging me along @lym953.

The main problem right now is that AWS won't respect the RUBYPATH, I have been trying to fix this for a while. And I'm still working on figuring out how to.

The workaround is to add datadog-lambda gem as a dependency, as opposed to a layer. Let me know if there are any questions. I'll raise an issue in datadog-lambda-rb to keep track of this!