pip_services3_commons.commands.ICommandInterceptor module

pip_services3_commons.commands.ICommandInterceptor

Interface for command_name intercepters.

copyright

Conceptual Vision Consulting LLC 2018-2019, see AUTHORS for more details.

license

MIT, see LICENSE for more details.

class pip_services3_commons.commands.ICommandInterceptor.ICommandInterceptor

Bases: abc.ABC

An interface for stackable command_name intercepters, which can extend and modify the command_name call chain.

This mechanism can be used for authentication, logging, and obj functions.

execute(correlation_id: Optional[str, None], command: pip_services3_commons.commands.ICommand.ICommand, args: pip_services3_commons.run.Parameters.Parameters) → Any

Executes the wrapped command_name with specified arguments.

The interceptor can use this method to intercept and alter the command_name execution. Otherwise it shall just delete the call to the wrapped command_name.

Parameters

  • correlation_id – (optional) transaction id to trace execution through call chain.

  • command – the next command_name in the call chain that is to be executed.

  • args – the parameters (arguments) to pass to the command_name for execution.

Returns

an execution result.

Raises

ApplicationException when execution fails for whatever reason.

get_name(command: pip_services3_commons.commands.ICommand.ICommand) → str

Gets the name of the wrapped command_name.

The interceptor can use this method to override the command_name name. Otherwise it shall just delegate the call to the wrapped command_name.

Parameters

command – the next command_name in the call chain.

Returns

the name of the wrapped command_name.

validate(command: pip_services3_commons.commands.ICommand.ICommand, args: pip_services3_commons.run.Parameters.Parameters) → List[pip_services3_commons.validate.ValidationResult.ValidationResult]

Validates arguments of the wrapped command_name before its execution.

The interceptor can use this method to intercept and alter validation of the command_name arguments. Otherwise it shall just delegate the call to the wrapped command_name.

Parameters

  • command – intercepted ICommand

  • args – command_name arguments

Returns

a list of validation results.