Module: SignalFx::Lambda

Defined in:
lib/signalfx/lambda.rb,
lib/signalfx/lambda/metrics.rb,
lib/signalfx/lambda/tracing.rb,
lib/signalfx/lambda/version.rb,
lib/signalfx/lambda/tracing/extractors.rb

Defined Under Namespace

Modules: Metrics, Tracing Classes: Error

Constant Summary collapse

COMPONENT = 
'ruby-lambda-wrapper'.freeze
VERSION = 
"0.2.2"

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.fields ⇒ Object

Returns the value of attribute fields.



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# File 'lib/signalfx/lambda.rb', line 12

def fields
  @fields
end

Class Method Details

.build_wrapped_handler(wrappers) ⇒ Object

build a nested block depending on the wrappers enabled



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# File 'lib/signalfx/lambda.rb', line 34

def build_wrapped_handler(wrappers)
  wrappers.inject do |inner, outer|
    proc do |event:, context:|
      outer.call(event: event, context: context, &inner)
    end
  end
end

.fields_from_arn(arn = '') ⇒ Object

the arn packs useful data, including region, account id, resource type, and qualifier



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# File 'lib/signalfx/lambda.rb', line 60

def fields_from_arn(arn = '')
  _, _, _, region, , resource_type, _, qualifier = arn.split(':')

  fields = {
    'aws_region' => region,
    'aws_account_id' => ,
  }

  if qualifier
    case resource_type
    when 'function'
      fields['aws_function_qualifier'] = qualifier
    when 'event-source-mappings'
      fields['event_source_mappings'] = qualifier
    end
  end

  fields
end

.gather_fields(context) ⇒ Object

build a map of useful properties from the context object



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# File 'lib/signalfx/lambda.rb', line 43

def gather_fields(context)
  fields = {
    'lambda_arn' => context.invoked_function_arn,
    'aws_request_id' => context.aws_request_id,
    'aws_function_name' => context.function_name,
    'aws_function_version' => context.function_version,
    'aws_execution_env' => ENV['AWS_EXECUTION_ENV'],
    'log_group_name' => context.log_group_name,
    'log_stream_name' => context.log_stream_name,
    'function_wrapper_version' => "signalfx-lambda-#{SignalFx::Lambda::VERSION}",
  }

  fields.merge!(fields_from_arn(context.invoked_function_arn))
end

.register_handler(metrics: true, tracing: true, &handler) ⇒ Object 



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# File 'lib/signalfx/lambda.rb', line 21

def register_handler(metrics: true, tracing: true, &handler)
  @handler = handler # the original handler

  # Add the wrappers needed
  wrappers = []
  wrappers.push(@handler)
  wrappers.push(Tracing.method(:wrap_function)) if tracing
  wrappers.push(Metrics.method(:wrap_function)) if metrics

  @wrapped_handler = build_wrapped_handler(wrappers) if @wrapped_handler.nil?
end

.wrapped_handler(event:, context:) ⇒ Object 



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# File 'lib/signalfx/lambda.rb', line 14

def wrapped_handler(event:, context:)
  # gather some useful information from the execution context and ARN and
  # make it available to the handlers
  @fields = gather_fields(context)
  @wrapped_handler.call(event: event, context: context)
end