Class: TransactionPinning::Middleware

Inherits:
Object
  • Object
show all
Defined in:
lib/fizzy/saas/transaction_pinning.rb

Constant Summary collapse

SESSION_KEY = 
:last_txn
DEFAULT_MAX_WAIT = 
0.25

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ Middleware

Returns a new instance of Middleware.



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# File 'lib/fizzy/saas/transaction_pinning.rb', line 6

def initialize(app)
  @app = app
  @timeout = Rails.application.config.x.transaction_pinning&.timeout&.to_f || DEFAULT_MAX_WAIT
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/fizzy/saas/transaction_pinning.rb', line 11

def call(env)
  request = ActionDispatch::Request.new(env)
  replica_metrics = {}

  if ApplicationRecord.current_role == :reading
    wait_for_replica_catchup(request, replica_metrics)
  end

  status, headers, body = @app.call(env)
  headers.merge!(replica_metrics.transform_values(&:to_s))

  if ApplicationRecord.current_role == :writing
    capture_transaction_id(request)
  end

  [ status, headers, body ]
end