feat(runner): add ability to export YAML OpenAPI specs (#62)

This commit gives developers the ability to also export YAML based
OpenAPI specs. These can be useful when wanting to create automatic API
documentation using documentation software like https://mintlify.com/.

runner/gen_openapi.py

@@ -2,28 +2,62 @@
 from app.main import app, use_route_names_as_operation_ids
 from app.routes import health, text_to_image, image_to_image, image_to_video
 import json
+import yaml
+import argparse
 
 
-def write_openapi_json(fname):
+def write_openapi(fname):
+    """Write OpenAPI schema to file.
+
+    Args:
+        fname (str): The file name to write to. The file extension determines the file
+            type. Either 'json' or 'yaml'.
+    """
     app.include_router(health.router)
     app.include_router(text_to_image.router)
     app.include_router(image_to_image.router)
     app.include_router(image_to_video.router)
 
     use_route_names_as_operation_ids(app)
 
+    # Write OpenAPI schema to file.
     with open(fname, "w") as f:
-        json.dump(
-            get_openapi(
-                title="Livepeer AI Runner",
-                version="0.1.0",
-                openapi_version=app.openapi_version,
-                description="An application to run AI pipelines",
-                routes=app.routes,
-            ),
-            f,
-        )
+        print(f"Writing OpenAPI schema to '{fname}'...")
+        if fname.endswith(".yaml"):
+            yaml.dump(
+                get_openapi(
+                    title="Livepeer AI Runner",
+                    version="0.1.0",
+                    openapi_version=app.openapi_version,
+                    description="An application to run AI pipelines",
+                    routes=app.routes,
+                ),
+                f,
+                sort_keys=False,
+            )
+        else:
+            json.dump(
+                get_openapi(
+                    title="Livepeer AI Runner",
+                    version="0.1.0",
+                    openapi_version=app.openapi_version,
+                    description="An application to run AI pipelines",
+                    routes=app.routes,
+                ),
+                f,
+            )
+        print("OpenAPI schema generated and saved.")
 
 
 if __name__ == "__main__":
-    write_openapi_json("openapi.json")
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--type",
+        type=str,
+        choices=["json", "yaml"],
+        default="json",
+        help="File type to write to, either 'json' or 'yaml'. Default is 'json'",
+    )
+    args = parser.parse_args()
+
+    write_openapi(f"openapi.{args.type.lower()}")