CLI 0.0.14, Uvicorn update and no more [serve] (langchain-ai#12845)

Calls uvicorn directly from cli:
Reload works if you define app by import string instead of object.
(was doing subprocess in order to get reloading)

Version bump to 0.0.14

Remove the need for [serve] for simplicity.

Readmes are updated in langchain-ai#12847 to avoid cluttering this PR

libs/cli/langchain_cli/cli.py

@@ -6,7 +6,7 @@
 from langchain_cli.namespaces import app as app_namespace
 from langchain_cli.namespaces import template as template_namespace
 
-__version__ = "0.0.13"
+__version__ = "0.0.14"
 
 app = typer.Typer(no_args_is_help=True, add_completion=False)
 app.add_typer(

libs/cli/langchain_cli/namespaces/app.py

@@ -220,8 +220,10 @@ def serve(
     """
 
     app_str = app if app is not None else "app.server:app"
-    port_str = str(port) if port is not None else "8000"
     host_str = host if host is not None else "127.0.0.1"
 
-    cmd = ["uvicorn", app_str, "--reload", "--port", port_str, "--host", host_str]
-    subprocess.run(cmd)
+    import uvicorn
+
+    uvicorn.run(
+        app_str, host=host_str, port=port if port is not None else 8000, reload=True
+    )

libs/cli/langchain_cli/namespaces/template.py

@@ -113,7 +113,6 @@ def serve(
     # get langserve export - throws KeyError if invalid
     get_langserve_export(pyproject)
 
-    port_str = str(port) if port is not None else "8000"
     host_str = host if host is not None else "127.0.0.1"
 
     script = (
@@ -122,14 +121,12 @@ def serve(
         else "langchain_cli.dev_scripts:create_demo_server_configurable"
     )
 
-    command = [
-        "uvicorn",
-        "--factory",
+    import uvicorn
+
+    uvicorn.run(
         script,
-        "--reload",
-        "--port",
-        port_str,
-        "--host",
-        host_str,
-    ]
-    subprocess.run(command)
+        factory=True,
+        reload=True,
+        port=port if port is not None else 8000,
+        host=host_str,
+    )