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How does AWS Lambda find and execute the specified handler in a function?

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I'm trying to understand how AWS Lambda can find and execute the specified handler in a Lambda function. Specifically, I would like to know:

  1. Handler Resolution Process: How does AWS Lambda use the handler configuration (e.g., MyNamespace.MyClass::MyMethod) to identify and invoke the correct method in a .NET application?

  2. Internal Mechanisms: What are the internal mechanisms or processes that AWS Lambda uses to load the class and execute the specified method in the handler?

  3. Technical Implementation: Is there any documentation or detailed technical explanation about how this "interference" is implemented in the AWS Lambda runtime?

  4. Comparison with Standard Entry Point: How does this approach of specifying a handler externally compare to defining a standard entry point, like the Main method, in terms of execution and flexibility?

I'm looking for technical details about the handler resolution and invocation process in AWS Lambda to better understand how this functionality is implemented and how it might be simulated or adapted in other contexts.

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AWS Lambda Handler Resolution in .NET Handler Configuration:

Format: MyNamespace.MyClass::MyMethod. Execution Steps:

Load Assembly: Lambda loads the .NET assembly. Use Reflection: Finds the class and method using reflection. Invoke Method: Instantiates the class (if needed) and calls the method. Internal Mechanisms:

AWS Lambda uses the .NET Core runtime to manage the lifecycle, initialize the handler, process input, and invoke the method. Technical Documentation:

Refer to AWS Lambda .NET Core Documentation for detailed information.
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when I define a lambda in terraform. I specify the file and handler method. whatever invokes it. calls that method
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AWS Lambda finds and executes handlers Handler editing process: AWS Lambda uses the .NET Framework reflection to identify and invoke specified methods in handlers.

* Lambda parses handler configuration (MyNamespace.MyClass::MyMethod) Separate namespace, class name, and method name.

* Lambda loads the relevant .NET assembly.

* Lambda uses reflection to find the specified class.

* Lambda uses reflection to search for methods specified in a class.

* Lambda calls the specified method by passing the specified arguments. Internal mechanism:

* Lambda caches loaded .NET assemblies for fast performance.

* Lambda uses JIT (Just-In-Time) compilation to convert .NET code into machine code that runs on Lambda's operating system.

* Lambda uses a separate sandbox to run .NET code. Technical usage:

* Official documentation from AWS on the handler editing mechanism:

* Sample code showing how to specify and call .NET methods in Lambda: Comparison with standard entry points:

* Action: Specifying a handler allows Lambda to call any method. in .NET applications without being limited to the Main method.

* Flexibility: Specifying handlers allows Lambda to modify how Lambda calls .NET applications. For example, Lambda can call multiple startup methods, or it can call different methods. Each depends on the event that triggers the Lambda. Advantages of specifying handlers:

* Increased flexibility for Lambda to run .NET applications.

* Allows calling any method in .NET applications

* Allows you to modify how Lambda runs .NET applications. Disadvantages of specifying handlers:

* Added complexity to Lambda configuration.

* May make code difficult to debug

* May make it difficult to secure Lambda summarize: Specifying handlers is a powerful feature of AWS Lambda that allows Lambda to call any method. in .NET applications However, it is important to be aware of the trade-offs before using this feature.