System Operations - PyPNM System Web Service Reload¶

Trigger A Hot Reload Of The PyPNM FastAPI Service During Development.

Table Of Contents¶

Overview
Endpoint
Request
Response
Notes
Field Tables

Overview¶

The PyPNM System Web Service Reload endpoint provides a lightweight way to signal a hot reload of the FastAPI application when it is running with an auto-reload process manager (for example, uvicorn --reload).

Internally, the endpoint touches the route module file to update its timestamp. When uvicorn (or an equivalent server) is configured with reload enabled, this file-change event triggers a code reload. This is intended primarily for development and test environments, not for production.

Endpoint¶

GET /pypnm/system/webService/reload

Request¶

No request body or query parameters are required.

The endpoint follows whatever global middleware you have configured for the API (authentication, logging, CORS, etc.).

Example Request (cURL)¶

curl -X GET "http://127.0.0.1:8000/pypnm/system/webService/reload"

If your service is exposed via HTTPS or a different interface/port, adjust the URL accordingly, for example:

curl -X GET "https://pypnm.example.net:443/pypnm/system/webService/reload"

Response¶

On success, the endpoint returns a small JSON object indicating that the reload trigger was issued. It does not wait for or validate that the reload has completed; it only reports whether the file-touch operation succeeded.

Successful Response¶

Status: 200 OK
Body (JSON):

{
  "status": "reload triggered"
}

Error Responses¶

If the underlying file-touch operation fails (for example, due to filesystem permissions or an unexpected runtime error), a 500 Internal Server Error is returned with a JSON payload.

Status: 500 Internal Server Error
Body (JSON):

{
  "detail": "Failed to trigger reload: <reason from underlying exception>"
}

The exact error message will depend on the underlying exception encountered while attempting to touch the route file.

Notes¶

This endpoint relies on the application being started with an auto-reload mechanism such as:

pypnm --reload

or:

uvicorn pypnm.main:app --reload

Without --reload (or an equivalent setting), touching the file will have no practical effect on a running production process.

The endpoint should generally be restricted to trusted users and non-production environments, as it influences application behavior and may cause transient unavailability during reloads.
The reload mechanism is implemented by updating the timestamp of the current route module:
If the file-touch operation succeeds, "status": "reload triggered" is returned.
If it fails, a 500 with an error detail is returned.

Field Tables¶

The response is a simple JSON object rather than a complex analysis payload. The contract is:

Element	Type	Description
HTTP method	`GET`	Read-only signal that attempts to trigger reload
URL path	string	`/pypnm/system/webService/reload`
Response body	object	JSON object with a `status` field.

Response Body Fields¶

Field	Type	Description
status	string	`"reload triggered"` on success, or an error status message.