Fixed API output data and replaced exactfit algorithm

Author: MirkoZETA

CHANGELOG.md

@@ -6,30 +6,31 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ### ROADMAP
-- Switch to Flex Net Sim v0.8.2.
-- Enhance previous algorithms.
-- Add algorithm BestFit.
 - Switch to new domain.
 
 ## [2.0.0] - 2025-03-03
 
 ### Added
-- New `/run_simulation_stream` endpoint for streaming simulation results in real-time
-- Refactored backend code to reduce duplication and improve maintainability
-- Added unit tests for the streaming endpoint
-- Modified `simulator.hpp` to flush stdout after each line for better streaming support (see `src/README.md`)
-- Improved help endpoint with more concise documentation
-- Enabled CORS only for `/run_simulation_stream` endpoint to allow controlled API access
+- New `/run_simulation_stream` endpoint for streaming simulation results in real-time:
+  - Streaming responses include event types and structured JSON data.
+- Refactored backend code to reduce duplication and improve maintainability.
+- Added unit tests for the streaming endpoint.
+- Modified `simulator.hpp` to flush `stdout` after each line for better streaming support (see `src/README.md`).
+- Improved the `\help` endpoint with more concise documentation.
+- Enabled CORS only for the `/run_simulation_stream` endpoint to allow controlled API access.
 
 ### Changed
+- Switched to Flex Net Sim v0.8.2.
 - Standardized API response format for better consistency:
-  - Success responses now use `status: "success"` with data in a `data` field
-  - Error responses now use `status: "error"` with a `message` and detailed `error` fields
-  - Streaming responses include event types and structured JSON data
-- Reorganized test suite into separate files for better maintainability
-- Improved parameter validation with descriptive error messages
-- Changed error response code from 500 to 400 for invalid parameters
-- Moved parameter validation from C++ to the API layer for better user experience
+  - Success responses now use `status: "success"` with data in a `data` field.
+  - Error responses now use `status: "error"` with a `message` and detailed `error` fields.
+- Reorganized the test suite into separate files for better maintainability.
+- Improved parameter validation with descriptive error messages.
+- Changed the error response code from `500` to `400` for invalid parameters.
+- Moved parameter validation from C++ to the API layer for a better user experience.
+- Replaced the `ExactFit` algorithm with `BestFit`.
+- Enhanced algorithms
+
 
 ## [1.1.1] - 2025-03-01
 
@@ -65,7 +66,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - This API hopefully serves as playground to all new users of Flex Net Sim C++ simulation library.
 - The current version utilizes Flex Net Sim v0.8.1.
 - `/run_simulation` endpoint for simulation includes parameters such as:
-    - `algorithm`: FirstFit, ExactFit.
+    - `algorithm`: FirstFit, BestFit.
     - `networkType`: Only 1 (EON) available for now.
     - `goalConnections`: 1 to 10,000,000.
     - `confidence`: significance level (alpha) greater than zero.

README.md

@@ -1,6 +1,6 @@
 # Flex Net Sim Backend API
 
-[![Static Badge](https://img.shields.io/badge/version-1.1.0-blue)](https://github.com/MirkoZETA/FlexNetSim-API)
+[![Static Badge](https://img.shields.io/badge/version-2.0.0-blue)](https://github.com/MirkoZETA/FlexNetSim-API)
 ![Static Badge](https://img.shields.io/badge/language-python-blue)
 [![Static Badge](https://img.shields.io/badge/licese-MIT-green)](https://github.com/MirkoZETA/FlexNetSim-API/blob/master/LICENSE)
 [![Static Badge](https://github.com/MirkoZETA/FlexNetSim-API/actions/workflows/fns-api-workflow.yml/badge.svg)](https://github.com/MirkoZETA/FlexNetSim-API/actions/workflows/fns-api-workflow.yml)
@@ -40,7 +40,7 @@ Runs a network simulation with the provided parameters and returns complete resu
 
 | Parameter       | Type      | Description                | Allowed Values & Constraints                                   | Default   |
 |---------------|---------|----------------------------|-------------------------------------------------|-----------|
-| `algorithm`    | `string`  | RSA algorithm              | `FirstFit`, `ExactFit`                         | `FirstFit` |
+| `algorithm`    | `string`  | RSA algorithm              | `FirstFit`, `BestFit`                         | `FirstFit` |
 | `networkType`  | `integer` | Network type               | Only `1` (EON) supported                        | `1`       |
 | `goalConnections` | `integer` | Target connection requests | Must be > 0 and < 10,000,000                   | `100000`  |
 | `confidence`   | `float`   | Confidence level           | Must be > 0 and < 1.0                           | `0.05`    |
@@ -134,7 +134,7 @@ The endpoint returns a stream of Server-Sent Events with the following event typ
 2. **Data Events** (multiple events, one per line of output):
    ```
    event: data
-   data: {"status": "running", "data": "Line of simulation output"}
+   data: {"status": "running", "message": "Line of simulation output"}
    ```
 
 3. **End Event**:

backend.py

@@ -4,6 +4,8 @@
 from flask import Flask, request, Response, stream_with_context
 from flask_cors import CORS
 from utils.helpers import *
+import time
+import json
 
 # --- Flask Application Setup --- 
 app = Flask(__name__)
@@ -76,65 +78,69 @@ def run_simulation():
 def run_simulation_stream():
   """
   Executes a network simulation with the provided parameters and streams the output.
-  
+
   Accepts a JSON request with simulation parameters and runs the C++ executable
   with those parameters. Returns a streaming response with simulation results
   as they become available.
-  
+
   Returns:
       Streaming response: Line-by-line simulation data
   """
   # Validate prerequisites
   is_valid, error_response = validate_simulation_prerequisites()
   if not is_valid:
     return error_response
-    
+
   try:
     data = request.get_json()
-    
+
     # Parse and validate parameters
     is_valid, result = parse_simulation_parameters(data)
     if not is_valid:
       return result
-    
+
     # Build command
     command = build_simulation_command(result)
     logger.debug(f"Running streaming simulation with command: {' '.join(command)}")
 
     # Create streaming function
     def generate():
       # Send initial event
-      yield f"event: start\ndata: {{\n  \"status\": \"started\",\n  \"message\": \"Simulation started\"\n}}\n\n"
-      
+      yield f"event: start\n"
+      yield f"data: {json.dumps({'status': 'started', 'message': 'Simulation started', 'timestamp': time.time()})}\n\n"
+
       # Execute simulation with streaming output
       process = subprocess.Popen(
-        command, 
-        stdout=subprocess.PIPE, 
-        stderr=subprocess.PIPE, 
+        command,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
         text=True,
         bufsize=1  # Line buffered
       )
-      
+
       # Stream stdout
       for line in iter(process.stdout.readline, ""):
         if line:
-          yield f"event: data\ndata: {{\n  \"status\": \"running\",\n  \"data\": \"{line.strip()}\"\n}}\n\n"
-          
+          yield f"event: data\n"
+          yield f"data: {json.dumps({'status': 'running', 'message': line.strip(), 'timestamp': time.time()})}\n\n"
+
       # Check for errors at the end
       process.stdout.close()
       return_code = process.wait()
-      
+
       if return_code != 0:
-        error = process.stderr.read()
-        yield f"event: error\ndata: {{\n  \"status\": \"error\",\n  \"message\": \"Simulation execution failed\",\n  \"error\": \"{error.strip()}\"\n}}\n\n"
-        logger.error(f"Streaming simulation failed. Return code: {return_code}, Error: {error.strip()}")
+        error = process.stderr.read().strip()
+        yield f"event: error\n"
+        yield f"data: {json.dumps({'status': 'error', 'message': 'Simulation execution failed', 'error': error, 'timestamp': time.time()})}\n\n"
+        logger.error(f"Streaming simulation failed. Return code: {return_code}, Error: {error}")
 
       # Close the stream resources
       process.stderr.close()
-      
+
       # Send completion event
-      yield f"event: end\ndata: {{\n  \"status\": \"completed\",\n  \"message\": \"Simulation completed\"\n}}\n\n"
-    
+      yield f"event: end\n"
+      yield f"data: {json.dumps({'status': 'completed', 'message': 'Simulation completed', 'timestamp': time.time()})}\n\n"
+
     return Response(
       stream_with_context(generate()),
       mimetype="text/event-stream",
@@ -150,8 +156,9 @@ def generate():
     logger.exception("Unexpected error during streaming simulation:")
     return jsonify({
       "status": "error",
-      "message": "An unexpected error occurred", 
-      "error": str(e)
+      "message": "An unexpected error occurred",
+      "error": str(e),
+      "timestamp": time.time()
     }), 500
 
 @app.route("/help", methods=["GET"])
@@ -174,7 +181,7 @@ def simulation_help():
     - /run_simulation_stream (POST): Streams results in real-time using Server-Sent Events
 
   COMMON PARAMETERS (JSON body, all optional):
-    algorithm: "FirstFit" or "ExactFit" (default: "FirstFit")
+    algorithm: "FirstFit" or "BestFit" (default: "FirstFit")
     networkType: 1 for EON (default: 1)
     goalConnections: 1-10000000 (default: 100000)
     confidence: 0-1 (default: 0.05)
@@ -206,7 +213,7 @@ def simulation_help():
         data: {"status": "started", "message": "Simulation started"}
 
         event: data
-        data: {"status": "running", "data": "Line of output"}
+        data: {"status": "running", "message": "Line of output"}
 
         event: end
         data: {"status": "completed", "message": "Simulation completed"}

requirements.txt

@@ -2,4 +2,5 @@ flask
 gunicorn
 pytest
 pytest-cov
-flask-testing
+flask-testing
+flask-cors