Added CLI to construct an OpenAPI schema of either the instrument server or backend server and save it as either a JSON or YAML file

Author: tieneupin

src/murfey/cli/generate_openapi_schema.py

@@ -0,0 +1,116 @@
+import contextlib
+import io
+import json
+from argparse import ArgumentParser
+from pathlib import Path
+
+import yaml
+from fastapi.openapi.utils import get_openapi
+
+import murfey
+from murfey.cli import LineWrapHelpFormatter, PrettierDumper
+
+
+def run():
+    # Set up argument parser
+    parser = ArgumentParser(
+        description=(
+            "Generates an OpenAPI schema of the chosen FastAPI server "
+            "and outputs it as either a JSON or YAML file"
+        ),
+        formatter_class=LineWrapHelpFormatter,
+    )
+    parser.add_argument(
+        "--target",
+        "-t",
+        default="server",
+        help=(
+            "The target FastAPI server to construct the OpenAPI schema for. \n"
+            "OPTIONS: instrument-server | server \n"
+            "DEFAULT: server"
+        ),
+    )
+    parser.add_argument(
+        "--output",
+        "-o",
+        default="yaml",
+        help=(
+            "Set the output format of the OpenAPI schema. \n"
+            "OPTIONS: json | yaml \n"
+            "DEFAULT: yaml"
+        ),
+    )
+    parser.add_argument(
+        "--to-file",
+        "-f",
+        default="",
+        help=(
+            "Alternative file path and file name to save the schema as. "
+            "Can be a relative or absolute path"
+        ),
+    )
+    parser.add_argument(
+        "--debug",
+        action="store_true",
+        default=False,
+        help="Shows additional steps when setting ",
+    )
+    args = parser.parse_args()
+
+    # Load the relevant FastAPI app
+    target = str(args.target).lower()
+    if args.debug:
+        print(f"Constructing OpenAPI schema for {target}")
+
+    # Silence output during import; only return genuine errors
+    buffer = io.StringIO()
+    with contextlib.redirect_stdout(buffer), contextlib.redirect_stderr(buffer):
+        if target == "server":
+            from murfey.server.main import app
+        elif target == "instrument-server":
+            from murfey.instrument_server.main import app
+        else:
+            raise ValueError(
+                "Unexpected value for target server. It must be one of "
+                "'instrument-server' or 'server'"
+            )
+
+    output = str(args.output).lower()
+    if not app.openapi_schema:
+        schema = get_openapi(
+            title=app.title,
+            version=app.version,
+            openapi_version=app.openapi_version,
+            description=app.description,
+            routes=app.routes,
+        )
+    else:
+        schema = app.openapi_schema
+
+    murfey_dir = Path(murfey.__path__[0])
+    save_path = (
+        murfey_dir / "util" / f"openapi.{output}"
+        if not args.to_file
+        else Path(args.to_file)
+    )
+    with open(save_path, "w") as f:
+        if output == "json":
+            json.dump(schema, f, indent=2)
+        elif output == "yaml":
+            yaml.dump(
+                schema,
+                f,
+                Dumper=PrettierDumper,
+                default_flow_style=False,
+                sort_keys=False,
+                indent=2,
+            )
+        else:
+            raise ValueError(
+                "Invalid file format select. Output must be either 'json' or 'yaml'"
+            )
+    print(f"OpenAPI schema save to {save_path}")
+
+
+if __name__ == "__main__":
+    run()