Module: Datadog::Tracing::Contrib::Sinatra::Framework

Defined in:
lib/datadog/tracing/contrib/sinatra/framework.rb

Overview

Sinatra framework code, used to essentially:

  • handle configuration entries which are specific to Datadog tracing

  • instrument parts of the framework when needed

Class Method Summary collapse

Class Method Details

.activate_rack!(datadog_config, sinatra_config) ⇒ Object

Apply relevant configuration from Sinatra to Rack



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 25

def self.activate_rack!(datadog_config, sinatra_config)
  datadog_config.tracing.instrument(
    :rack,
    service_name: sinatra_config[:service_name],
    distributed_tracing: sinatra_config[:distributed_tracing],
  )
end

.add_middleware(middleware, builder, *args, &block) ⇒ Object Also known as: unshift_middleare

Add Rack middleware at the top of the stack



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 34

def self.add_middleware(middleware, builder, *args, &block)
  insert_middleware(builder, middleware, args, block) do |proc_, use|
    use.insert(0, proc_)
  end
end

.add_middleware_after(after, middleware, builder, *args, &block) ⇒ Object

Add Rack middleware after another in the the stack



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 63

def self.add_middleware_after(after, middleware, builder, *args, &block)
  index = middlewares(builder).index(after)

  raise "middleware #{after} not found" unless index

  insert_middleware(builder, middleware, args, block) do |proc_, use|
    use.insert(index + 1, proc_)
  end
end

.add_middleware_before(before, middleware, builder, *args, &block) ⇒ Object

Add Rack middleware before another in the stack



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 52

def self.add_middleware_before(before, middleware, builder, *args, &block)
  index = middlewares(builder).index(before)

  raise "middleware #{before} not found" unless index

  insert_middleware(builder, middleware, args, block) do |proc_, use|
    use.insert(index, proc_)
  end
end

.append_middleware(middleware, builder, *args, &block) ⇒ Object

Add Rack middleware at the top of the stack



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 45

def self.append_middleware(middleware, builder, *args, &block)
  insert_middleware(builder, middleware, args, block) do |proc_, use|
    use.append(proc_)
  end
end

.config_with_defaults(datadog_config) ⇒ Object 



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 20

def self.config_with_defaults(datadog_config)
  datadog_config.tracing[:sinatra]
end

.include_middleware?(middleware, builder) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 96

def self.include_middleware?(middleware, builder)
  middlewares(builder).include?(middleware)
end

.insert_middleware(builder, middleware, args, block) ⇒ Object

Insert a middleware class in the builder as it expects it internally. The block gets passed prepared arguments for the caller to decide how to insert.



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 83

def self.insert_middleware(builder, middleware, args, block)
  use = builder.instance_variable_get('@use')
  wrapped = wrap_middleware(middleware, *args, &block)

  # Makes the insert idempotent
  # The block can also throw :skip with its own logic
  catch(:skip) do
    throw(:skip) if middlewares(builder).include?(middleware)

    yield(wrapped, use)
  end
end

.inspect_middlewares(builder) ⇒ Object 



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 109

def self.inspect_middlewares(builder)
  Datadog.logger.debug { +'Sinatra middlewares: ' << middlewares(builder).map(&:inspect).inspect }
end

.middlewares(builder) ⇒ Object

Introspect middlewares from a builder



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 101

def self.middlewares(builder)
  builder.instance_variable_get(:@use).map do |proc_|
    next :unknown unless proc_.respond_to?(:binding) && proc_.binding.local_variable_defined?(:middleware)

    proc_.binding.local_variable_get(:middleware)
  end
end

.setup ⇒ Object

Configure Rack from Sinatra, but only if Rack has not been configured manually beforehand



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 13

def self.setup
  Datadog.configure do |datadog_config|
    sinatra_config = config_with_defaults(datadog_config)
    activate_rack!(datadog_config, sinatra_config)
  end
end

.wrap_middleware(middleware, *args, &block) ⇒ Object

Wrap the middleware class instantiation in a proc, like Sinatra does internally The ‘middleware` local variable name in the proc is important for introspection (see Framework#middlewares)



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# File 'lib/datadog/tracing/contrib/sinatra/framework.rb', line 76

def self.wrap_middleware(middleware, *args, &block)
  proc { |app| middleware.new(app, *args, &block) }
end