fastapi doc : added Query Adavaned Param

Docs/Services/FastAPI/10-Query-Auth.md

@@ -0,0 +1,184 @@
+# FastAPI – Advanced Query Parameters (`Query`)
+
+This document demonstrates how to configure **query parameters** in FastAPI using `Query()` to add:
+
+* Aliases
+* Descriptions (for API documentation)
+* Deprecation warnings
+* Validation and metadata
+
+It also shows how these configurations appear in the **OpenAPI / Swagger UI**.
+
+---
+
+## Example Application
+
+Create or update `main.py` with the following content:
+
+```python
+from fastapi import FastAPI, Query, status
+from fastapi.responses import JSONResponse
+
+app = FastAPI()
+
+users_db = [
+    {"id": "1", "name": "radin"}
+]
+
+
+@app.get("/user/")
+def get_user_deprecated(
+    target: int | None = Query(
+        default=None,
+        alias="User ID",
+        description="Enter target unique ID",
+        deprecated=True,
+    )
+):
+    for item in users_db:
+        if int(item["id"]) == target:
+            return JSONResponse(
+                content={"msg": f"Your target user name is {item['name']}"},
+                status_code=status.HTTP_200_OK,
+            )
+
+    return JSONResponse(
+        content={"msg": "user not found"},
+        status_code=status.HTTP_404_NOT_FOUND,
+    )
+
+
+@app.get("/user")
+def get_user(
+    target: int | None = Query(
+        default=None,
+        alias="User ID",
+        description="Enter target unique ID",
+    )
+):
+    for item in users_db:
+        if item["id"] == str(target):
+            return JSONResponse(
+                content={"msg": f"Your target user name is {item['name']}"},
+                status_code=status.HTTP_200_OK,
+            )
+
+    return JSONResponse(
+        content={"msg": "user not found"},
+        status_code=status.HTTP_404_NOT_FOUND,
+    )
+```
+
+---
+
+## Query Parameter Configuration
+
+### `Query()` Parameters Used
+
+```python
+Query(
+    default=None,
+    alias="User ID",
+    description="Enter target unique ID",
+    deprecated=True
+)
+```
+
+| Parameter     | Purpose                                     |
+| ------------- | ------------------------------------------- |
+| `default`     | Makes the query parameter optional          |
+| `alias`       | Changes the query parameter name in the URL |
+| `description` | Appears in Swagger UI documentation         |
+| `deprecated`  | Marks the parameter as deprecated           |
+
+---
+
+## Example Requests
+
+### Using Alias in Query String
+
+```http
+GET /user?User%20ID=1
+```
+
+---
+
+## Endpoint Behavior
+
+### Deprecated Endpoint
+
+```http
+GET /user/
+```
+
+* Query parameter is marked as **deprecated**
+* Swagger UI displays a warning
+* Useful for backward compatibility
+
+---
+
+### Active Endpoint
+
+```http
+GET /user
+```
+
+* Uses the same alias and description
+* Recommended for active usage
+
+---
+
+## Response Examples
+
+### Success Response
+
+```json
+{
+  "msg": "Your target user name is radin"
+}
+```
+
+Status Code: **200 OK**
+
+---
+
+### Failure Response
+
+```json
+{
+  "msg": "user not found"
+}
+```
+
+Status Code: **404 Not Found**
+
+---
+
+## Swagger / OpenAPI Integration
+
+* Alias appears as the query parameter name
+* Description is visible in API docs
+* Deprecated parameters are clearly marked
+* Improves API discoverability and usability
+
+---
+
+## Running the Application
+
+Start the service using `uvicorn`:
+
+```bash
+uvicorn main:app --reload
+```
+
+---
+
+## Best Practices
+
+* Use `Query()` for validation and documentation
+* Avoid spaces in aliases for production APIs
+* Deprecate parameters instead of removing them
+* Keep backward compatibility during API evolution
+* Prefer consistent parameter naming
+* Use response models instead of manual `JSONResponse` when possible
+