"Update" button for simpler upgrades of TruBudget versions

[jzakotnik]

Discussed in https://github.com/openkfw/TruBudget/discussions/1754

^{Originally posted by **jzakotnik** March 27, 2024} One pain point from the pilots is that the upgrading is a somewhat complex process and no "update" Button exists in TruBudget. What would be the options and architecture how this could be done?

[galethil]

Hi @jzakotnik I believe that in order to accomplish this we will need to introduce new piece of infrastructure on the level of server where docker is running.

Here's a high-level description of the solution:

High-Level Steps to Enable an "Upgrade" Button for Docker Infrastructure

1. Host-Level Script:

   • Create a shell script (upgrade.sh) on the host machine that:
     • Updates the environment variable with the new Docker image tag.
     • Pulls the new Docker images.
     • Restarts the services using Docker Compose.

2. Host-Level API Service:

   • Set up a lightweight API server on the host machine using Node.js and Express.
   • This server will expose an endpoint to trigger the upgrade.sh script.

3. Backend Service:

   • Modify your backend service (running in a container) to send HTTP requests to the host-level API.
   • This backend service will handle requests from the frontend to initiate the upgrade process.

4. Frontend Integration:

   • Add an "Upgrade" button to your frontend.
   • This button will send a request to the backend service with the desired new version tag.

5. Secure Communication:

   • Ensure secure communication between the backend service and the host-level API to prevent unauthorized access.

Workflow

1. User Interaction:

   • A user clicks the "Upgrade" button on the frontend and enters the desired version tag.

2. Frontend Request:

   • The frontend sends the version tag to the backend service.

3. Backend Processing:

   • The backend service forwards the version tag to the host-level API.

4. Host-Level Execution:

   • The host-level API triggers the upgrade.sh script to update the environment variables, pull the new images, and restart the services using Docker Compose.

By following these high-level steps, you can set up your infrastructure to support an "Upgrade" button on the frontend, allowing seamless upgrades of your Docker-based application.

graph TD;
    A[Frontend] -->|1. Click 'Upgrade' Button| B[Backend Service];
    B -->|2. Send Version Tag| C[Host-Level API];
    C -->|3. Trigger upgrade.sh| D[upgrade.sh Script];
    D -->|4. Update .env and Pull New Images| E[Docker Compose];
    E -->|5. Restart Services| F[Docker Services];

    style A fill:#f9f,stroke:#333,stroke-width:4px;
    style B fill:#bbf,stroke:#333,stroke-width:4px;
    style C fill:#f96,stroke:#333,stroke-width:4px;
    style D fill:#ff9,stroke:#333,stroke-width:4px;
    style E fill:#96f,stroke:#333,stroke-width:4px;
    style F fill:#6f9,stroke:#333,stroke-width:4px;