Fix .env port conflict between backend and frontend (Next.js) when running on the same device

[Breezewrf]

Hi there,

As mentioned by #114, the issue occurs because both the backend and the Next.js frontend read the PORT variable from .env.
(I suspect it, not for sure, but experimented) Setting PORT=8001 causes both to try to use the same port, resulting in a conflict.

Solution

• Use Server_PORT instead of PORT in .env, and updated backend code to read from Server_PORT instead of PORT.
• Updated documentation and .env usage to recommend using Server_PORT (or SERVER_PORT) for the backend, and leaving PORT for the frontend.
• Added a note to use SERVER_BASE_URL in the .env to point to the backend.

This resolves the port conflict and allows both servers to run simultaneously on the same device.

[gemini-code-assist]

Hello @Breezewrf, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

Summary of Changes

Hello! Gemini here, providing a summary of this pull request. This PR addresses an issue where both the backend API server and the Next.js frontend application might attempt to use the same PORT environment variable when run on the same machine, leading to a port conflict. The core change involves renaming the environment variable used by the backend from PORT to Server_PORT to avoid this conflict. The backend code is updated to read from the new variable, and the documentation is modified to guide users on setting Server_PORT for the backend, allowing the frontend to use its default PORT configuration, and how to configure the frontend to connect to the backend using SERVER_BASE_URL.

Highlights

• Port Conflict Resolution: Resolves a potential port conflict when running the backend and frontend on the same device by using distinct environment variables for their respective ports.
• Backend Configuration Update: Changes the backend API server to read its listening port from the Server_PORT environment variable instead of PORT.
• Documentation Enhancement: Updates the Ollama instruction documentation to recommend using Server_PORT for the backend, clarify the port conflict issue, and advise on setting SERVER_BASE_URL for frontend-backend communication.

Changelog

• Ollama-instruction.md
  • Updated the example .env configuration to use Server_PORT=8001 instead of PORT=8001.
  • Added a detailed note explaining the port conflict issue when running frontend and backend together, recommending Server_PORT for the backend and SERVER_BASE_URL for frontend configuration.
• api/main.py
  • Modified the main execution block to retrieve the server port from the Server_PORT environment variable, falling back to 8001 if not set, instead of using PORT.

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---

Ports clash, a digital fight,
Backend needs its own number, bright.
Server_PORT now reigns,
Documentation explains,
Both servers can run, day and night.

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[gemini-code-assist]

Code Review

This PR effectively addresses the port conflict issue (#114) for local development by introducing Server_PORT for the backend, allowing PORT to be used by the frontend without collision. The changes in api/main.py and the intent behind the documentation updates in Ollama-instruction.md are good.

However, there are a few areas for improvement:

1. Documentation Clarity: The example for port configuration in Ollama-instruction.md needs refinement to avoid new confusion.
2. Docker Configuration Impact (Critical): These changes have a significant impact on the existing docker-compose.yml configuration, which is not addressed in this PR. If the Docker setup is intended to work post-merge, docker-compose.yml will need corresponding updates. Without them, the backend service in Docker will likely be unreachable or misconfigured.
3. Variable Naming Consistency: While the code and .env examples now use Server_PORT, the PR description mentions (or SERVER_PORT). It's best to maintain strict consistency with Server_PORT everywhere to avoid confusion.

I've added specific comments on the documentation. The Docker impact is a major concern that needs to be addressed or acknowledged.

Summary of Findings

• Documentation Clarity on Port Configuration: The example in Ollama-instruction.md (line 55) for setting frontend and backend ports is contradictory and could cause port conflicts. It needs to clearly state that frontend and backend ports must be different.
• Docker Compose Configuration Mismatch (Critical): The changes to use Server_PORT in the backend Python application will break the current docker-compose.yml setup. The docker-compose.yml file still relies on the PORT environment variable for port mapping and SERVER_BASE_URL configuration for the backend service. This needs to be updated to use Server_PORT to ensure the Dockerized backend is reachable and correctly configured. For example, port mappings should change from ${PORT:-8001}:${PORT:-8001} to ${Server_PORT:-8001}:${Server_PORT:-8001} and SERVER_BASE_URL should also reflect Server_PORT.
• Documentation Phrasing: The explanation on line 57 of Ollama-instruction.md regarding the purpose of Server_PORT could be phrased more clearly for better readability.
• Environment Variable Naming Consistency: The code and .env examples correctly use Server_PORT. It's recommended to ensure this exact casing is used consistently across all documentation and discussions, avoiding alternatives like SERVER_PORT to prevent confusion.

Merge Readiness

This pull request makes a good step towards resolving the port conflict issue for local development. However, due to the critical impact on the Docker configuration (which is not updated in this PR) and the need for clarification in the documentation, I recommend that these changes be addressed before merging.

Specifically, the docker-compose.yml file needs to be updated to align with the use of Server_PORT for the backend. Without this, the Docker setup will likely fail or behave unexpectedly. The documentation also needs the suggested adjustments for clarity.

As a reviewer, I am not authorized to approve the pull request. Please ensure these points are considered and further review is conducted before merging.

[gemini-code-assist]

The example provided here, "set Server_PORT=8001 for the backend and leave the frontend to use its default port 8001," is contradictory and could lead to the same port conflict this PR aims to solve. If the backend uses port 8001, the frontend cannot use the same port on the same device.

Next.js typically defaults to port 3000. If a user customizes the frontend port using the PORT variable in .env, it must be different from Server_PORT.

Could you update this line to provide a clearer and non-conflicting example?

Suggested change

	- For example, set `Server_PORT=8001` for the backend and leave the frontend to use its default port 8001.
	- For example, set `Server_PORT=8001` in your `.env` file for the backend. The frontend (e.g., Next.js) will use the `PORT` variable from `.env` (if you set one for it) or its own default port (e.g., 3000). Ensure the frontend's port is different from `Server_PORT`.

[gemini-code-assist]

The phrasing "to prevent frontend take it into configuration" is a little awkward and could be clearer. How about rephrasing to better explain the benefit of using separate port variables?

Suggested change

	- Use `Server_PORT` instead of `PORT` to prevent frontend take it into configuration if frontend and backend running on identical device.
	- Use `Server_PORT` for the backend's port. If your frontend also reads a `PORT` variable from the `.env` file (as Next.js does), ensure it's set to a different value. This separation prevents both applications from attempting to use the same port configuration when reading from the same `.env` file.