th2-act 1.0.0.dev2446701100

th2_act

TH2 Act Component (Python)

Overview

This repository is a library for custom gRPC act projects (check th2-act-template-py for the implementation template). The th2-act contains helper methods to create custom ActHadlers that implements custom gRPC API. Multiple ActHandlers allowed as well.

Act is a passive th2 component with parameterized functions which is implemented as part of the test logic. Script or other components can call these functions via gRPC. Act can interact with conn (Connects), hands, check1s, other acts to execute its tasks. Information about the progress of the task is published to the estore th2 component via MQ pin. This th2 component type allows frequently used script logic into it and then share it between all th2 components.

Most of them consists of the next steps:

1. Gets a gRPC request with parameters.
2. Requests checkpoint from check1 via gRPC pin
3. Sends the passed business message to Connect via mq pin
4. Waits the specific business message from Connect during specified timeout
5. Returns responded business message with checkpoint

Installation

To install th2-act package run the following command in the terminal:

pip install th2-act

Usage

Classes Act and GRPCServer may be used in act implementation to upload act-handlers and run gRPC server.

RequestProcessor context manager may be used in act implementation to send requests to conn, save all received messages to the cache and retrieve messages from there using the filters described by the user.

RequestProcessor has several methods to work with its cache:

• method that returns first message that matches one of the filters:

  receive_first_matching(message_filters: Dict[Callable, int],
                         timeout: Union[int, float] = None,
                         check_previous_messages: bool = True) -> ActResponse
  

• method that returns first N messages that match the filters:

  receive_first_n_matching(message_filters: Dict[Callable, int],
                           n: int,
                           timeout: Union[int, float] = None,
                           check_previous_messages: bool = True) -> List[ActResponse]
  

• method that returns all messages preceding the first message (including it) that matches one of the filters:

  receive_all_before_matching(message_filters: Dict[Callable, int],
                              timeout: Union[int, float] = None,
                              check_previous_messages: bool = True) -> List[ActResponse]
  

• method that returns all messages following the first message (including it) that matches one of the filters:

  receive_all_after_matching(message_filters: Dict[Callable, int],
                             wait_time: Union[int, float] = None,
                             check_previous_messages: bool = True) -> List[ActResponse]
  

• method that returns all messages that match the filters:

  receive_all_matching(message_filters: Dict[Callable, int],
                       wait_time: Union[int, float] = None,
                       check_previous_messages: bool = True) -> List[ActResponse]
  

Methods have the following arguments:

Name	Status	Type	Defaults	Meaning
message_filters	required	Dict[lambda, RequestStatus.status]	-	The filter (lambda or function) through which the messages from cache will be filtered out - as key, RequestStatus (SUCCESS or ERROR) - as value.
n	required	int	-	How much messages to return.
timeout	optional	int of float	context time remaining	The time (in seconds) during which you are ready to wait for the messages. The messages will be returned as soon as the first matching message is found.
wait_time	optional	int of float	None	The time (in seconds) that the Act will wait before checking the cache for the matching message. Defaults to None (cache will be checked immediately and only once).
check_previous_messages	optional	bool	True	Set True if you want to look for the response throughout all received responses; set False if you want to check only newly received responses.

All methods return either a ActResponse class instance or a list of ActResponse class instances. ActResponse class contains the following fields:

• message - Message
• status - RequestStatus
• checkpoint - CheckpointID
• text - str

Schematically, the interaction with the RequestProcessor class can be represented as follows:

Implementation template is here.