Metadata-Version: 2.4
Name: comm-ipc
Version: 0.1.0
Summary: A lightweight IPC library with bridge and streaming support
Author-email: shashstormer <shashanka5398@gmail.com>
License:                    GNU LESSER GENERAL PUBLIC LICENSE
                               Version 3, 29 June 2007
        
         Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
         Everyone is permitted to copy and distribute verbatim copies
         of this license document, but changing it is not allowed.
        
        
          This version of the GNU Lesser General Public License incorporates
        the terms and conditions of version 3 of the GNU General Public
        License, supplemented by the additional permissions listed below.
        
          0. Additional Definitions.
        
          As used herein, "this License" refers to version 3 of the GNU Lesser
        General Public License, and the "GNU GPL" refers to version 3 of the GNU
        General Public License.
        
          "The Library" refers to a covered work governed by this License,
        other than an Application or a Combined Work as defined below.
        
          An "Application" is any work that makes use of an interface provided
        by the Library, but which is not otherwise based on the Library.
        Defining a subclass of a class defined by the Library is deemed a mode
        of using an interface provided by the Library.
        
          A "Combined Work" is a work produced by combining or linking an
        Application with the Library.  The particular version of the Library
        with which the Combined Work was made is also called the "Linked
        Version".
        
          The "Minimal Corresponding Source" for a Combined Work means the
        Corresponding Source for the Combined Work, excluding any source code
        for portions of the Combined Work that, considered in isolation, are
        based on the Application, and not on the Linked Version.
        
          The "Corresponding Application Code" for a Combined Work means the
        object code and/or source code for the Application, including any data
        and utility programs needed for reproducing the Combined Work from the
        Application, but excluding the System Libraries of the Combined Work.
        
          1. Exception to Section 3 of the GNU GPL.
        
          You may convey a covered work under sections 3 and 4 of this License
        without being bound by section 3 of the GNU GPL.
        
          2. Conveying Modified Versions.
        
          If you modify a copy of the Library, and, in your modifications, a
        facility refers to a function or data to be supplied by an Application
        that uses the facility (other than as an argument passed when the
        facility is invoked), then you may convey a copy of the modified
        version:
        
           a) under this License, provided that you make a good faith effort to
           ensure that, in the event an Application does not supply the
           function or data, the facility still operates, and performs
           whatever part of its purpose remains meaningful, or
        
           b) under the GNU GPL, with none of the additional permissions of
           this License applicable to that copy.
        
          3. Object Code Incorporating Material from Library Header Files.
        
          The object code form of an Application may incorporate material from
        a header file that is part of the Library.  You may convey such object
        code under terms of your choice, provided that, if the incorporated
        material is not limited to numerical parameters, data structure
        layouts and accessors, or small macros, inline functions and templates
        (ten or fewer lines in length), you do both of the following:
        
           a) Give prominent notice with each copy of the object code that the
           Library is used in it and that the Library and its use are
           covered by this License.
        
           b) Accompany the object code with a copy of the GNU GPL and this license
           document.
        
          4. Combined Works.
        
          You may convey a Combined Work under terms of your choice that,
        taken together, effectively do not restrict modification of the
        portions of the Library contained in the Combined Work and reverse
        engineering for debugging such modifications, if you also do each of
        the following:
        
           a) Give prominent notice with each copy of the Combined Work that
           the Library is used in it and that the Library and its use are
           covered by this License.
        
           b) Accompany the Combined Work with a copy of the GNU GPL and this license
           document.
        
           c) For a Combined Work that displays copyright notices during
           execution, include the copyright notice for the Library among
           these notices, as well as a reference directing the user to the
           copies of the GNU GPL and this license document.
        
           d) Do one of the following:
        
               0) Convey the Minimal Corresponding Source under the terms of this
               License, and the Corresponding Application Code in a form
               suitable for, and under terms that permit, the user to
               recombine or relink the Application with a modified version of
               the Linked Version to produce a modified Combined Work, in the
               manner specified by section 6 of the GNU GPL for conveying
               Corresponding Source.
        
               1) Use a suitable shared library mechanism for linking with the
               Library.  A suitable mechanism is one that (a) uses at run time
               a copy of the Library already present on the user's computer
               system, and (b) will operate properly with a modified version
               of the Library that is interface-compatible with the Linked
               Version.
        
           e) Provide Installation Information, but only if you would otherwise
           be required to provide such information under section 6 of the
           GNU GPL, and only to the extent that such information is
           necessary to install and execute a modified version of the
           Combined Work produced by recombining or relinking the
           Application with a modified version of the Linked Version. (If
           you use option 4d0, the Installation Information must accompany
           the Minimal Corresponding Source and Corresponding Application
           Code. If you use option 4d1, you must provide the Installation
           Information in the manner specified by section 6 of the GNU GPL
           for conveying Corresponding Source.)
        
          5. Combined Libraries.
        
          You may place library facilities that are a work based on the
        Library side by side in a single library together with other library
        facilities that are not Applications and are not covered by this
        License, and convey such a combined library under terms of your
        choice, if you do both of the following:
        
           a) Accompany the combined library with a copy of the same work based
           on the Library, uncombined with any other library facilities,
           conveyed under the terms of this License.
        
           b) Give prominent notice with the combined library that part of it
           is a work based on the Library, and explaining where to find the
           accompanying uncombined form of the same work.
        
          6. Revised Versions of the GNU Lesser General Public License.
        
          The Free Software Foundation may publish revised and/or new versions
        of the GNU Lesser General Public License from time to time. Such new
        versions will be similar in spirit to the present version, but may
        differ in detail to address new problems or concerns.
        
          Each version is given a distinguishing version number. If the
        Library as you received it specifies that a certain numbered version
        of the GNU Lesser General Public License "or any later version"
        applies to it, you have the option of following the terms and
        conditions either of that published version or of any later version
        published by the Free Software Foundation. If the Library as you
        received it does not specify a version number of the GNU Lesser
        General Public License, you may choose any version of the GNU Lesser
        General Public License ever published by the Free Software Foundation.
        
          If the Library as you received it specifies that a proxy can decide
        whether future versions of the GNU Lesser General Public License shall
        apply, that proxy's public statement of acceptance of any version is
        permanent authorization for you to choose that version for the
        Library.
Requires-Python: >=3.8
Description-Content-Type: text/markdown
License-File: LICENSE.txt
Provides-Extra: test
Requires-Dist: pytest; extra == "test"
Requires-Dist: pytest-asyncio; extra == "test"
Dynamic: license-file

# CommIPC: Asynchronous Secure Distributed Inter-Process Communication

CommIPC is an asynchronous Inter-Process Communication (IPC) system designed for Linux environments. Written in pure Python, it provides communication through Unix Domain Sockets for local processes and TCP for cross-network communication, featuring integrated bridging, synchronization, and security mechanisms.

## Table of Contents

- [Key Features](#key-features)
- [Architecture Overview](#architecture-overview)
- [Components](#components)
- [Usage Guide](#usage-guide)
    - [Basic RPC (Request-Response)](#basic-rpc-request-response)
    - [Streaming Responses](#streaming-responses)
    - [Cross-Network Bridging](#cross-network-bridging)
- [Performance and Scalability](#performance-and-scalability)
- [Testing](#testing)
- [License](#license)

## Key Features

- **Zero-Trust Security**:
    - **HMAC-SHA256 Handshake**: Mandatory cryptographic challenge for every client connection.
    - **End-to-End Signature**: All channel messages are signed with HMAC-SHA256 based on channel passwords, ensuring data integrity even if the server is compromised.
- **Advanced Channel Management**:
    - **Owner-Based Administration**: The first client to join a channel is the Admin/Owner, with exclusive rights to manage security.
    - **Explicit Password Protection**: Support for protecting channels (including system channels) with unique, cryptographically derived keys.
    - **Flexible Lifecycle Policies**: Configurable policies for handling owner disconnection (`terminate` or `promote`).
- **High Resilience**:
    - **Auto-Reconnect**: Robust reconnection logic with exponential backoff and transparent state restoration (channels, providers).
    - **Synchronous Persistence**: Client APIs wait for server confirmation for registrations and security changes, preventing communication hangs.
- **Dependency-Free**: Implemented entirely using the Python standard library, requiring no external packages.

## Architecture Overview

The system operates as a hub-and-spoke model locally, which can be extended into a mesh or linear topology using bridges.

```mermaid
graph TD
    subgraph "Local Network A"
        SrvA["CommIPCServer (Primary)"]
        CliA1["Client A1"] <--> SrvA
        CliA2["Client A2"] <--> SrvA
    end
    
    subgraph "Bridge Link"
        Bridge["CommIPCBridge"]
    end
    
    subgraph "Remote Network B"
        SrvB["CommIPCServer (Secondary)"]
        CliB1["Client B1"] <--> SrvB
    end
    
    SrvA <--> Bridge <--> SrvB
```

## Components

- **CommIPCServer**: The central message coordinator responsible for client lifecycle management, authentication, and message routing.
- **CommIPC**: The primary client interface for application integration.
- **CommIPCChannel**: A high-level abstraction layer for interacting with specific logical communication channels.
- **CommIPCBridge**: A specialized interconnect service that synchronizes providers and subscribers across discrete server instances.

## Usage Guide

### Basic RPC (Request-Response)

#### Service Provider

```python
import asyncio
from comm_ipc.client import CommIPC

async def main():
    client = CommIPC(client_id="math_service")
    channel = await client.open("math_operations")
    
    def add(params):
        return params.data["a"] + params.data["b"]
        
    await channel.add_event("sum", call=add)
    
    # Maintain the service loop
    await asyncio.Future() 

if __name__ == "__main__":
    asyncio.run(main())
```

#### Service Consumer

```python
import asyncio
from comm_ipc.client import CommIPC

async def main():
    client = CommIPC(client_id="application_client")
    channel = await client.open("math_operations")
    
    response = await channel.event("sum", {"a": 15, "b": 25})
    print(f"Calculated Sum: {response.data}") # Expected Output: 40

if __name__ == "__main__":
    asyncio.run(main())
```

### Streaming Responses

#### Stream Provider

```python
async def sequence_generator(request):
    n = request.data.get("limit", 10)
    for i in range(n):
        yield i
        await asyncio.sleep(0.05)

await channel.add_stream("data_feed", call=sequence_generator)
```

#### Stream Consumer

```python
async for chunk in channel.stream("data_feed", {"limit": 5}):
    print(f"Received Chunk: {chunk.data}")
```

### Cross-Network Bridging

```python
from comm_ipc.bridge import CommIPCBridge

# Establishes a link between a local Unix socket and a remote TCP server
bridge = CommIPCBridge(socket_path1="/tmp/local_service.sock")
await bridge.connect(
    target1_params={}, 
    target2_params={"host": "192.168.1.100", "port": 9000}
)
```

### Security & Channel Management

#### Protecting a Channel (Owner)

```python
# The first client to open the channel becomes the owner
channel = await client.open("secure-data")
await client.set_password("secure-data", "strong-password")
```

#### Joining a Protected Channel

```python
# Fails if password is wrong or missing
channel = await client.open("secure-data", password="strong-password")
```

#### Protecting System Channels

You can secure internal system channels (logs, errors, registration events) by providing a `system_passwords` dictionary when initializing the server:

```python
server = CommIPCServer(
    system_passwords={
        "__comm_ipc_logs": "log-secret",
        "__comm_ipc_errors": "error-secret",
        "__comm_ipc_system": "sys-secret"
    }
)
```

## Performance and Resilience

CommIPC is optimized for reliability:
- **Auto-Reconnect**: Automatically recovers from server restarts and network interruptions.
- **State Preservation**: Transparently restores all active channel memberships and event providers after a reconnection event.
- **Optional Client Logging**: Clients are silent by default; set `verbose=True` during initialization to enable terminal logging.
- **Unix Domain Sockets**: Minimizes latency for local-host communication by bypassing the network stack.

## Testing

The project maintains a comprehensive verification suite located in the `tests/` directory.

```bash
# Execute the full validation suite
PYTHONPATH=. pytest tests/
```

The test coverage includes:
- **Zero-Trust Verification**: HMAC handshakes, signature integrity, and E2E verification.
- **Advanced Management**: Ownership logic, lifecycle policies, and resource cleanup.
- **Resilience**: Auto-reconnect stability and state restoration.
- **Distributed Systems**: Bridge synchronization and circular path detection.
- **Streaming**: Asynchronous iterator support across local and remote instances.

## License

This project is licensed under the LGPLv3 License.
