add URL_PREFIX config for reverse proxy path support

app/api/routes.py

@@ -17,6 +17,12 @@ from app.database import check_content_hash, get_db
 # Valid paste ID pattern (hexadecimal only)
 PASTE_ID_PATTERN = re.compile(r"^[a-f0-9]+$")
 
+
+def _url(path: str) -> str:
+    """Generate URL with configured prefix for reverse proxy deployments."""
+    prefix = current_app.config.get("URL_PREFIX", "")
+    return f"{prefix}{path}"
+
 # Runtime-generated PoW secret (used if not configured)
 _pow_secret_cache = None
 
@@ -273,22 +279,25 @@ def index():
     if request.method == "POST":
         return create_paste()
 
+    prefix = current_app.config.get("URL_PREFIX", "")
     return _json_response(
         {
             "name": "FlaskPaste",
             "version": VERSION,
+            "prefix": prefix or "/",
             "endpoints": {
-                "GET /": "API information",
+                f"GET {_url('/')}": "API information",
-                "GET /health": "Health check",
+                f"GET {_url('/health')}": "Health check",
-                "POST /": "Create paste",
+                f"GET {_url('/challenge')}": "Get PoW challenge",
-                "GET /<id>": "Retrieve paste metadata",
+                f"POST {_url('/')}": "Create paste",
-                "GET /<id>/raw": "Retrieve raw paste content",
+                f"GET {_url('/<id>')}": "Retrieve paste metadata",
-                "DELETE /<id>": "Delete paste",
+                f"GET {_url('/<id>/raw')}": "Retrieve raw paste content",
+                f"DELETE {_url('/<id>')}": "Delete paste",
             },
             "usage": {
-                "raw": "curl --data-binary @file.txt http://host/",
+                "raw": f"curl --data-binary @file.txt http://host{_url('/')}",
-                "pipe": "cat file.txt | curl --data-binary @- http://host/",
+                "pipe": f"cat file.txt | curl --data-binary @- http://host{_url('/')}",
-                "json": "curl -H 'Content-Type: application/json' -d '{\"content\":\"...\"}' http://host/",
+                "json": f"curl -H 'Content-Type: application/json' -d '{{\"content\":\"...\"}}' http://host{_url('/')}",
             },
             "note": "Use --data-binary (not -d) to preserve newlines",
         }
@@ -382,8 +391,8 @@ def create_paste():
 
     response_data = {
         "id": paste_id,
-        "url": f"/{paste_id}",
+        "url": _url(f"/{paste_id}"),
-        "raw": f"/{paste_id}/raw",
+        "raw": _url(f"/{paste_id}/raw"),
         "mime_type": mime_type,
         "created_at": now,
     }
@@ -420,7 +429,7 @@ def get_paste(paste_id: str):
         "mime_type": row["mime_type"],
         "size": row["size"],
         "created_at": row["created_at"],
-        "raw": f"/{paste_id}/raw",
+        "raw": _url(f"/{paste_id}/raw"),
     })
 
 

app/config.py

@@ -44,6 +44,9 @@ class Config:
     # Secret key for signing challenges (auto-generated if not set)
     POW_SECRET = os.environ.get("FLASKPASTE_POW_SECRET", "")
 
+    # URL prefix for reverse proxy deployments (e.g., "/paste" for mymx.me/paste)
+    URL_PREFIX = os.environ.get("FLASKPASTE_URL_PREFIX", "").rstrip("/")
+
 
 class DevelopmentConfig(Config):
     """Development configuration."""