Method: Faulty::Circuit#run

Defined in:
lib/faulty/circuit.rb

#run(cache: nil) { ... } ⇒ Object

Run a block protected by this circuit

If the circuit is closed, the block will run. Any exceptions raised inside the block will be checked against the error and exclude options to determine whether that error should be captured. If the error is captured, this run will be recorded as a failure.

If the circuit exceeds the failure conditions, this circuit will be tripped and marked as open. Any future calls to run will not execute the block, but instead wait for the cool down period. Once the cool down period passes, the circuit transitions to half-open, and the block will be allowed to run.

If the circuit fails again while half-open, the circuit will be closed for a second cool down period. However, if the circuit completes successfully, the circuit will be closed and reset to its initial state.

When this is run, the given options are persisted to the storage backend.

Parameters:

  • cache (String, nil) (defaults to: nil) —

    A cache key, or nil if caching is not desired

Yields:

  • The block to protect with this circuit

Returns:

  • The return value of the block

Raises:

  • If the block raises an error not in the error list, or if the error is excluded.

  • (OpenCircuitError) —

    if the circuit is open

  • (CircuitTrippedError) —

    if this run causes the circuit to trip. It's possible for concurrent runs to simultaneously trip the circuit if the storage engine is not concurrency-safe.

  • (CircuitFailureError) —

    if this run fails, but doesn't cause the circuit to trip



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# File 'lib/faulty/circuit.rb', line 308

def run(cache: nil, &block)
  push_options
  cached_value = cache_read(cache)
  # return cached unless cached.nil?
  return cached_value if !cached_value.nil? && !cache_should_refresh?(cache)

  current_status = status
  if current_status.can_run? && reserve(current_status)
    run_exec(current_status, cached_value, cache, &block)
  else
    run_skipped(cached_value)
  end
end