Add readonly, public metadata service

Closes #2 (closed)

geomagio/api/ws/app.py

@@ -20,6 +20,7 @@ ERROR_CODE_MESSAGES = {
     503: "Service Unavailable",
 }
 
+METADATA_ENDPOINT = bool(os.getenv("METADATA_ENDPOINT", False))
 VERSION = os.getenv("GEOMAG_VERSION", "version")
 
 
@@ -28,9 +29,11 @@ app = FastAPI(docs_url="/docs", root_path="/ws")
 app.include_router(algorithms.router)
 app.include_router(data.router)
 app.include_router(elements.router)
-app.include_router(metadata.router)
 app.include_router(observatories.router)
 
+if METADATA_ENDPOINT:
+    app.include_router(metadata.router)
+
 
 @app.middleware("http")
 async def add_headers(request: Request, call_next):