Merge pull request #13 from MITLibraries/IN-1441-base-url-flag

IN 1441 - support a base URL on notebook launch

Author: ghukill

README.md

@@ -118,21 +118,20 @@ NOTEBOOK_PORT= ### port to serve running notebook on
 Base command
 
 ```text
-Usage: launcher [OPTIONS] COMMAND [ARGS]...
+Usage: uv run marimo-launcher [OPTIONS] COMMAND [ARGS]...
 
 Options:
   -v, --verbose  Pass to log at debug level instead of info
   --help         Show this message and exit.
 
 Commands:
-  run
-  validate
+  run  Launch notebook in 'run' or 'edit' mode.
 ```
 
 ### `launcher run`
 
 ```text
-Usage: python -m launcher.cli run [OPTIONS]
+Usage: uv run marimo-launcher run [OPTIONS]
 
   Launch notebook in 'run' or 'edit' mode.
 
@@ -154,6 +153,9 @@ Options:
   --port INTEGER       port to bind (env: NOTEBOOK_PORT)  [default: 2718]
   --token TEXT         set a required authentication token/password for the
                        notebook; if not set, no token/password is required
+                       (env: NOTEBOOK_TOKEN)
+  --base-url TEXT      explicit base URL prefix to pass through to marimo on
+                       notebook launch (env: NOTEBOOK_BASE_URL)
   --help               Show this message and exit.
 ```
 

launcher/cli.py

@@ -94,7 +94,17 @@ def cli(
     show_default=True,
     help=(
         "set a required authentication token/password for the notebook; "
-        "if not set, no token/password is required"
+        "if not set, no token/password is required (env: NOTEBOOK_TOKEN)"
+    ),
+)
+@click.option(
+    "--base-url",
+    envvar="NOTEBOOK_BASE_URL",
+    default=None,
+    show_default=True,
+    help=(
+        "explicit base URL prefix to pass through to marimo on notebook launch "
+        "(env: NOTEBOOK_BASE_URL)"
     ),
 )
 @click.pass_context
@@ -110,6 +120,7 @@ def run(
     host: str,
     port: int,
     token: str | None,
+    base_url: str | None,
 ) -> None:
     """Launch notebook in 'run' or 'edit' mode."""
     notebook_dir_path = resolve_notebook_directory(
@@ -126,6 +137,7 @@ def run(
         token=token,
         notebook_path=notebook_path,
         requirements_file=requirements_file,
+        base_url=base_url,
     )
 
     logger.info(f"launching notebook '{full_notebook_path}' with args {cmd}")
@@ -230,6 +242,7 @@ def prepare_run_command(
     token: str | None,
     notebook_path: str,
     requirements_file: Path | None,
+    base_url: str | None = None,
 ) -> list[str]:
     """Build the shell command used to launch a marimo notebook via `uv run`.
 
@@ -253,6 +266,8 @@ def prepare_run_command(
         - notebook_path: path to the marimo notebook file.
         - requirements_file: optional path to a requirements file for `uv` (enables
             `--with-requirements`).
+        - base_url: base URL path launched notebook will listen on
+            e.g. host:port/<base_url>
     """
     # start with `uv run` so marimo executes in a managed Python environment
     cmd: list[str] = ["uv", "run"]
@@ -281,6 +296,10 @@ def prepare_run_command(
     else:
         cmd += ["--no-token"]
 
+    # set base url flag if passed
+    if base_url:
+        cmd += ["--base-url", base_url]
+
     # path to the notebook is the final positional argument
     cmd += [str(notebook_path)]
 

tests/fixtures/inline_deps/notebook.py

@@ -2,7 +2,7 @@
 # requires-python = ">=3.13"
 # dependencies = [
 #     "marimo",
-#     "tinydb==4.8.2",
+#     "tinydb",
 # ]
 # ///
 

tests/test_cli.py

@@ -139,6 +139,43 @@ def test_cli_subprocess_run_minimal_required_args_get_defaults_success(runner):
     ]
 
 
+def test_cli_subprocess_run_base_url_override(runner):
+    args = [
+        "run",
+        "--mount",
+        "tests/fixtures/inline_deps",
+        "--base-url",
+        "/my/super/path.py",
+    ]
+
+    with mock.patch("launcher.cli.subprocess.run") as mock_subprocess_run:
+        mock_subprocess_run.return_value = subprocess.CompletedProcess(
+            args=args, returncode=0
+        )
+        _result = runner.invoke(cli, args)
+
+    # assert subproces.run has correct working directory of notebook
+    assert mock_subprocess_run.call_args.kwargs.get("cwd") == "tests/fixtures/inline_deps"
+
+    # assert subprocess.run had defaults applied
+    assert mock_subprocess_run.call_args.args[0] == [
+        "uv",
+        "run",
+        "marimo",
+        "run",
+        "--headless",
+        "--host",
+        "0.0.0.0",
+        "--port",
+        "2718",
+        "--sandbox",
+        "--no-token",
+        "--base-url",
+        "/my/super/path.py",
+        "notebook.py",
+    ]
+
+
 def test_cli_subprocess_run_missing_mount_or_repo_args_error(runner):
     args = ["run"]