ReMIP Server

This directory contains the ReMIP FastAPI server, which provides a RESTful API for solving Mixed-Integer Programming (MIP) problems.

Running the Server

To run the server, you need to have the dependencies installed (e.g., via uv pip install -e . from this directory). Then, you can start the server using the remip command:

uv run remip --host 0.0.0.0 --port 8000

The server will automatically find an open port if 8000 is in use, unless a specific port is provided.

API Endpoints

GET /solver-info

Returns information about the underlying MIP solver.

• Method: GET
• Success Response: 200 OK
• Response Body Example:

  {
    "solver": "SCIP",
    "version": "x.y.z"
  }
  

POST /solve

Solves a MIP problem. It can return the solution directly or stream solver events using Server-Sent Events (SSE).

• Method: POST
• Query Parameters:
  • timeout (float, optional): Maximum time in seconds to allow the solver to run.
  • stream (string, optional): If set to sse, the server will stream solver events.
• Request Body: A JSON object representing the MIPProblem.
• Success Response: 200 OK

Request Body (MIPProblem)

The request body must be a JSON object with the following structure:

{
  "parameters": {
    "name": "MyProblem",
    "sense": 1,
    "status": 0,
    "sol_status": 0
  },
  "objective": {
    "name": "TotalProfit",
    "coefficients": [
      { "name": "x1", "value": 10 },
      { "name": "x2", "value": 15 }
    ]
  },
  "variables": [
    { "name": "x1", "cat": "Binary" },
    { "name": "x2", "cat": "Binary" }
  ],
  "constraints": [
    {
      "name": "ResourceA",
      "sense": -1,
      "coefficients": [
        { "name": "x1", "value": 2 },
        { "name": "x2", "value": 5 }
      ],
      "constant": 10
    }
  ],
  "solver_options": {
    "limits/time": 60
  }
}

Standard Response (MIPSolution)

If the stream parameter is not set, the response will be a JSON object with the solution:

{
  "name": "MyProblem",
  "status": "optimal",
  "objective_value": 25.0,
  "variables": {
    "x1": 1.0,
    "x2": 1.0
  }
}

Streaming Response (SSE)

If stream=sse is specified, the response will be a text/event-stream. The client will receive a sequence of events, such as log, metric, result, and end.

Example Event:

event: metric
data: {"timestamp":"...","objective_value":25.0,"gap":0.0,"iteration":10,"sequence":5}