Python hot loading Class library Hot-Redis original analysis

Python hot loading Class library Hot-Redis original analysis In Python development, the use of heat loading can realize dynamic updates and loading code during running without stopping the current operation.This article will analyze the principle of a hot loading Class library Hot-Redis. 1. Hot-Redis Introduction Hot-Redis is a Class library used in Python applications to achieve hot loading and update of code based on the Import mechanism of Python and INSPECT modules.Through hot-redis, developers can dynamically change and load the implementation of the Python class during runtime without restarting the application. 2. Python's Import mechanism In Python, the Import statement is a keyword for importing other Python modules and packages.When the Python interpreter executes the Import statement, it searches and loads related modules.When loading the module, the interpreter executes a series of steps, including the source code of the parsing module, the creation of the corresponding module object, and the top -level statement in the execution module. 3. The working principle of hot-redis The working principle of hot-redis can be divided into the following steps: Step 1: Monitor the specified python module Hot-Redis monitor the specified Python module. When the module changes, Hot-Redis will start a sub-process to reload the module. Step 2: Import and analyze the module When the module changes, Hot-Redis uses the Import mechanism of Python to import and analyze the module.The process of analyzing the module will create a module object and perform the top -level statement in the module. Step 3: Check the definition After the module parsing is completed, Hot-Redis uses the INSPECT module to check the class definition in the module.The INSPECT module provides functions and classes for checking the source code.By using the Inspect module, Hot-Redis can obtain and analyze the class definition in the module. Step 4: Re -load the module When the class definition in the module changes, the HOT-Redis will reload the module and create a new class object.In this way, the previously created object -based objects will be updated as objects defined based on new classes. Step 5: Update the object in the application By releasing modules and updating class definitions, Hot-Redis has realized dynamic updates of objects in applications.This means that developers can modify the implementation of the class at runtime, and the objects based on the application in the application will be automatically updated. 4. Example code and related configuration The following is a sample code using hot-redis for heat loading: python from hot_redis import HotRedis class MyClass: def __init__(self, name): self.name = name def greet(self): print(f"Hello, {self.name}!") # Create a hotdis object redis = HotRedis() # Register a module to be monitored redis.monitor_module("my_module.py") # Set the timer, check whether the module changes every other time redis.set_timer(5) # 运 while True: # Get the updated class object updated_class = redis.get_updated_class(MyClass) if updated_class: # Update the object in the application my_instance.__class__ = updated_class my_instance.greet() In the above sample code, a Hotredis object is first created, and modules to be monitored through the method of `Monitor_module ()`.Then set the timer using the `set_timer ()` method to check whether the module changes every time.Finally, obtain the updated object in the infinite loop and update the objects in the application. It should be noted that in order to use Hot-Redis, the corresponding dependencies need to be installed.You can install Hot-Redis through PIP: bash $ pip install hot-redis In addition, it is necessary to ensure that the hot_redis module is correctly introduced in the code. Summarize: This article analyzes the principle of Python thermal loading Class library Hot-Redis.Hot loading can be dynamically updated and loaded during runtime without the need to stop the execution of the current program.By using Python's Import mechanism and INSPECT module, HOT-Redis can realize the dynamic loading and update of the module, thereby achieving hot updates of the implementation of the application in the application.By example code and corresponding configuration, we can also use Hot-Redis to experience the effect of hot loading.