Class: XRay::LambdaContext

Inherits:
DefaultContext show all
Defined in:
lib/aws-xray-sdk/lambda/lambda_context.rb

Overview

LambdaContext extends the default context so that we can provide an appropriate FacadeSegment as the root context for each function invocation.

Constant Summary collapse

TRACE_ID_ENV_VAR = 
'_X_AMZN_TRACE_ID'.freeze

Constants inherited from DefaultContext

DefaultContext::CONTEXT_MISSING_KEY, DefaultContext::DEFAULT_STRATEGY, DefaultContext::LOCAL_KEY, DefaultContext::SUPPORTED_STRATEGY

Instance Attribute Summary

Attributes inherited from DefaultContext

#context_missing

Instance Method Summary collapse

Methods inherited from DefaultContext

#clear!, #handle_context_missing, #initialize, #inject_context, #store_entity

Methods included from Logging

#logger, logger, logger=

Methods included from Context

#clear!, #handle_context_missing, #inject_context, #store_entity

Constructor Details

This class inherits a constructor from XRay::DefaultContext

Instance Method Details

#check_context ⇒ Object

If the environment trace id changes, create a new facade for that segment and make it the context’s current entity



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# File 'lib/aws-xray-sdk/lambda/lambda_context.rb', line 17

def check_context
  #Create a new FacadeSegment if the _X_AMZN_TRACE_ID changes.
  return if lambda_trace_id == @current_trace_id

  @current_trace_id = lambda_trace_id
  trace_header = XRay::TraceHeader.from_header_string(header_str: @current_trace_id)
  segment = FacadeSegment.new(trace_id: trace_header.root,
    parent_id: trace_header.parent_id,
    id: trace_header.parent_id,
    name: 'lambda_context',
    sampled: trace_header.sampled == 1
  )
  store_entity(entity: segment)
end

#current_entity ⇒ Object 



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# File 'lib/aws-xray-sdk/lambda/lambda_context.rb', line 32

def current_entity
  check_context #ensure the FacadeSegment is current whenever the current_entity is retrieved
  super
end

#lambda_trace_id ⇒ Object 



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# File 'lib/aws-xray-sdk/lambda/lambda_context.rb', line 11

def lambda_trace_id
  ENV[TRACE_ID_ENV_VAR]
end