Method: Jets::PolyFun::BaseExecutor#run_lambda_executor

Defined in:
lib/jets/poly_fun/base_executor.rb

#run_lambda_executor(event, context) ⇒ Object

When polymorphic method errors, this method reproduces an error in the lambda format Here’s some examples to help example:

Example of what the raw python prints out to stderr:

Traceback (most recent call last):
  File "/tmp/jets/lite/executor/20180804-10727-mcs6qk/lambda_executor.py", line 6, in <module>
    resp = handle(event, context)
  File "/tmp/jets/lite/executor/20180804-10727-mcs6qk/index.py", line 22, in handle
    return response({'message': e.message}, 400)
  File "/tmp/jets/lite/executor/20180804-10727-mcs6qk/index.py", line 5, in response
    badcode
NameError: global name 'badcode' is not defined

So last line has the error summary info. Other lines have stack trace after the Traceback indicator.

Example of the reproduced lambda error format:

{
  "errorMessage": "'NameError' object has no attribute 'message'",
  "errorType": "AttributeError",
  "stackTrace": [
    [
      "/var/task/handlers/controllers/posts_controller/python/index.py",
      22,
      "handle",
      "return response({'message': e.message}, 400)"
    ]
  ]
}



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# File 'lib/jets/poly_fun/base_executor.rb', line 86

def run_lambda_executor(event, context)
  interpreter = @task.lang
  command = %Q|#{interpreter} #{lambda_executor_script} '#{JSON.dump(event)}' '#{JSON.dump(context)}'|
  stdout, stderr, status = Open3.capture3(command)
  # puts "=> #{command}".color(:green)
  # puts "stdout #{stdout}"
  # puts "stderr #{stderr}"
  # puts "status #{status}"
  if status.success?
    stdout
  else
    # We'll mimic the way lambda displays an error.
    # $stderr.puts(stderr) # uncomment to debug
    error_lines = stderr.split("\n")
    error_message = error_lines.pop
    error_type = error_message.split(':').first
    error_lines.shift # remove first line that has the Traceback
    stack_trace = error_lines.reverse # python shows stack trace in opposite order from ruby
    JSON.dump(
      "errorMessage" => error_message,
      "errorType" => error_type, # hardcode
      "stackTrace" => stack_trace
    )
  end
end