pip-services4-components 0.0.8

Description:

pipservices4components 0.0.8

Portable Component Model for Python
This module is a part of the Pip.Services polyglot microservices toolkit.
It defines a portable component model interfaces and provides utility classes to handle component lifecycle.
The module contains the following packages:

Build - basic factories for constructing objects
Config - configuration pattern
Refer - locator inversion of control (IoC) pattern
Run - component life-cycle management patterns

Quick links:

Logging
Configuration
API Reference
Change Log
Get Help
Contribute

Use
Install the Python package as
pip install pip_services4_components

Then you are ready to start using the Pip.Services patterns to augment your backend code.
For instance, here is how you can implement a component, that receives configuration, get assigned references,
can be opened and closed using the patterns from this module.
from pip_services4_commons.config import IConfigurable, ConfigParams
from pip_services4_commons.refer import IReferenceable, IReferences, Descriptor
from pip_services4_commons.run import IOpenable


class MyComponentA(IConfigurable, IReferenceable, IOpenable):
_param1 = 'ABC'
_param2 = 123
_another_component: MyComponentB
_opened = True

def configure(self, config):
self._param1 = ConfigParams.get_as_string_with_default("param1", self._param1)
self._param2 = config.get_as_integer_with_default("param2", self._param2)

def set_references(self, references):
self._another_component = references.get_one_required(
Descriptor("myservice", "mycomponent-b", "*", "*", "1.0")
)

def is_opened(self):
return self._opened

def open(self, context):
self._opened = True
print("MyComponentA has been opened.")

def close(self, context):
self._opened = True
print("MyComponentA has been closed.")

Then here is how the component can be used in the code
from pip_services4_commons.config import IConfigurable, ConfigParams
from pip_services4_commons.refer import References, Descriptor

my_component_A = MyComponentA()

# Configure the component
my_component_A.configure(ConfigParams.from_tuples(
'param1', 'XYZ',
'param2', 987
))

# Set references to the component
my_component_A.set_references(References.from_tuples(
Descriptor("myservice", "mycomponent-b", "default", "default", "1.0"), my_component_B
))

# Open the component
my_component_A.open(Context.from_trace_id("123"))
print("MyComponentA has been opened.")

If you need to create components using their locators (descriptors) implement
component factories similar to the example below.
from pip_services4_commons.refer import Descriptor
from pip_services4_components.build import Factory


class MyFactory(Factory):
my_component_descriptor = Descriptor("myservice", "mycomponent", "default", "*", "1.0")

def __init__(self):
super(MyFactory, self).__init__()

self.register_as_type(MyFactory.my_component_descriptor, MyFactory)


# Using the factory
my_factory = MyFactory()
my_component1 = my_factory.create(Descriptor("myservice", "mycomponent", "default", "myComponent1", "1.0"))
my_component2 = my_factory.create(Descriptor("myservice", "mycomponent", "default", "myComponent2", "1.0"))

...

Develop
For development you shall install the following prerequisites:

Python 3.7+
Visual Studio Code or another IDE of your choice
Docker

Install dependencies:
pip install -r requirements.txt

Run automated tests:
python test.py

Generate API documentation:
./docgen.ps1

Before committing changes run dockerized build and test as:
./build.ps1
./test.ps1
./clear.ps1

Contacts
The initial implementation is done by Sergey Seroukhov. Pip.Services team is looking for volunteers to
take ownership over Python implementation in the project.