th2 common library (Python)

Installation

pip install th2-common

This package can be found on PyPI.

Usage

First things first, you need to import CommonFactory class:

from th2_common.schema.factory.common_factory import CommonFactory

Then you create an instance of imported class, choosing one of the options:

Create factory with configs from default path (/var/th2/config/*):
```
factory = CommonFactory()
```
Create factory with configs from specified directory path (path/*):
```
factory = CommonFactory(config_path=...)
```

Create factory with configs from specified file paths:

factory = CommonFactory(rabbit_mq_config_filepath=...,
                        mq_router_config_filepath=...,
                        grpc_router_config_filepath=...,
                        cradle_config_filepath=...,
                        custom_config_filepath=...)

Create factory with configs from command line arguments (sys.argv):
```
factory = CommonFactory.create_from_arguments()
```

Create factory with configs from specified arguments:

factory = CommonFactory.create_from_arguments(args)

Create factory with a namespace in Kubernetes and the name of the target th2 box from Kubernetes:
```
factory = CommonFactory.create_from_kubernetes(namespace, box_name)
```

Requirements for creatring factory with Kubernetes

It is necessary to have Kubernetes configuration written in ~/.kube/config. See more on kubectl configuration here.
It is necessary to have environment variables CASSANDRA_PASS and RABBITMQ_PASS to use configs from cradle.json and rabbitMQ.json as the passwords are not stored there explicitly.
Also note that generated_configs directory will be created to store .json files with configs from Kubernetes. Those files are overridden when CommonFactory.create_from_kubernetes(namespace, box_name) is invoked again.

After that you can get various Routers through factory properties:

message_parsed_batch_router = factory.message_parsed_batch_router
message_raw_batch_router = factory.message_raw_batch_router
event_batch_router = factory.event_batch_router

message_parsed_batch_router is working with MessageBatch
message_raw_batch_router is working with RawMessageBatch
event_batch_router is working with EventBatch

See th2-grpc-common for details.

With router created, you can subscribe to pins (specifying callback function) or send data that router works with:

router.subscribe(callback)  # subscribe to only one pin 
router.subscribe_all(callback)  # subscribe to one or several pins
router.send(message)  # send to only one pin
router.send_all(message)  # send to one or several pins

You can do these actions with extra pin attributes in addition to default ones.

router.subscribe(callback, attrs...)  # subscribe to only one pin
router.subscribe_all(callback, attrs...)  # subscribe to one or several pins
router.send(message, attrs...)  # send to only one pin
router.send_all(message, attrs...)  # send to one or several pins

Default attributes are:

message_parsed_batch_router
- Subscribe: subscribe, parsed
- Send: publish, parsed
message_raw_batch_router
- Subscribe: subscribe, raw
- Send: publish, raw
event_batch_router
- Subscribe: subscribe, event
- Send: publish, event

Metadata

Release files for th2-common 2.4.1.dev682920856

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for th2-common 2.4.1.dev682920856
File	Size	Uploaded
th2_common-2.4.1.dev682920856.tar.gz	24.7 kB	Mar 24, 2021	Details

Release files / th2_common-2.4.1.dev682920856.tar.gz

Download URL	th2_common-2.4.1.dev682920856.tar.gz
Size	24.7 kB
Tags	Source
SHA-256 checksum How to use checksums	`54a5983a74d8212d5459fb227c127fe281360efde53ff57cfe385a594b56977d`
BLAKE2b-256 checksum How to use checksums	`207f13a5220ecae03d48103cd385525d4381ff69dcba8e7210bfd36a862654d4`
Upload date	Mar 24, 2021
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/3.4.1 importlib_metadata/3.7.3 pkginfo/1.7.0 requests/2.25.1 requests-toolbelt/0.9.1 tqdm/4.59.0 CPython/3.9.2`