WIP: monorepo support in CLI (#6028)

This PR introduces the `--build-command` and `--install-command`
arguments to `langgraph build`.

`--install-command` is a custom install command. If passed, it will be
run from wherever the `langgraph build` call was made, i.e. NOT where
the langgraph.json file lives (except if these are the same place). This
will override the detected install command that we previously used.

`--build-command` is a custom build command. This will run from wherever
the langgraph.json file lives, and will be done after the install has
been run.

You don't need to provide both. Just providing one will make the install
(detected or supplied) run in the directory from where `langgraph build
was called` and then have the build command (if one exists) run in the
directory where langgraph.json exists.

I think we should probably allow configuring the directories from which
these commands get run, but I don't think this needs to be part of the
MVP.

---------

Co-authored-by: William FH <13333726+hinthornw@users.noreply.github.com>

libs/cli/langgraph_cli/__init__.py

@@ -1 +1 @@
-__version__ = "0.4.0"
+__version__ = "0.4.1"

libs/cli/langgraph_cli/cli.py

@@ -303,6 +303,8 @@ def _build(
     pull: bool,
     tag: str,
     passthrough: Sequence[str] = (),
+    install_command: Optional[str] = None,
+    build_command: Optional[str] = None,
 ):
     # pull latest images
     if pull:
@@ -322,22 +324,38 @@ def _build(
         "-t",
         tag,
     ]
+    # determine build context: use current directory for JS projects, config parent for Python
+    is_js_project = config_json.get("node_version") and not config_json.get(
+        "python_version"
+    )
+    # build/install commands only apply to JS projects for now
+    # without install/build command, JS projects will follow the old behavior
+    if is_js_project and (build_command or install_command):
+        build_context = str(pathlib.Path.cwd())
+    else:
+        build_context = str(config.parent)
+
     # apply config
     stdin, additional_contexts = langgraph_cli.config.config_to_docker(
-        config, config_json, base_image, api_version
+        config,
+        config_json,
+        base_image,
+        api_version,
+        install_command,
+        build_command,
+        build_context,
     )
     # add additional_contexts
     if additional_contexts:
         for k, v in additional_contexts.items():
             args.extend(["--build-context", f"{k}={v}"])
-    # run docker build
     runner.run(
         subp_exec(
             "docker",
             "build",
             *args,
             *passthrough,
-            str(config.parent),
+            build_context,
             input=stdin,
             verbose=True,
         )
@@ -366,6 +384,14 @@ def _build(
     "\n    --base-image langchain/langgraph-server:0.2  # Pin to a minor version (Python)",
 )
 @OPT_API_VERSION
+@click.option(
+    "--install-command",
+    help="Custom install command to run from the build context root. If not provided, auto-detects based on package manager files.",
+)
+@click.option(
+    "--build-command",
+    help="Custom build command to run from the langgraph.json directory. If not provided, uses default build process.",
+)
 @click.argument("docker_build_args", nargs=-1, type=click.UNPROCESSED)
 @cli.command(
     help="📦 Build LangGraph API server Docker image.",
@@ -381,6 +407,8 @@ def build(
     api_version: Optional[str],
     pull: bool,
     tag: str,
+    install_command: Optional[str],
+    build_command: Optional[str],
 ):
     with Runner() as runner, Progress(message="Pulling...") as set:
         if shutil.which("docker") is None:
@@ -397,6 +425,8 @@ def build(
             pull,
             tag,
             docker_build_args,
+            install_command,
+            build_command,
         )
 
 

libs/cli/langgraph_cli/config.py

@@ -913,10 +913,10 @@ def _assemble_local_deps(config_path: pathlib.Path, config: Config) -> LocalDeps
                         "Rename the directory to use it as flat-layout package."
                     )
                 check_reserved(resolved.name, local_dep)
-                container_path = f"/deps/__outer_{resolved.name}/{resolved.name}"
+                container_path = f"/deps/outer-{resolved.name}/{resolved.name}"
             else:
                 # src layout
-                container_path = f"/deps/__outer_{resolved.name}/src"
+                container_path = f"/deps/outer-{resolved.name}/src"
                 for file in files:
                     rfile = resolved / file
                     if (
@@ -1286,7 +1286,7 @@ def python_config_to_docker(
     if local_deps.pip_reqs:
         pip_reqs_str = os.linesep.join(
             (
-                f"COPY --from=__outer_{reqpath.name} requirements.txt {destpath}"
+                f"COPY --from=outer-{reqpath.name} requirements.txt {destpath}"
                 if reqpath.parent in local_deps.additional_contexts
                 else f"ADD {reqpath.relative_to(config_path.parent)} {destpath}"
             )
@@ -1305,7 +1305,7 @@ def python_config_to_docker(
     faux_pkgs_str = f"{os.linesep}{os.linesep}".join(
         (
             f"""# -- Adding non-package dependency {fullpath.name} --
-COPY --from=__outer_{fullpath.name} . {destpath}"""
+COPY --from=outer-{fullpath.name} . {destpath}"""
             if fullpath in local_deps.additional_contexts
             else f"""# -- Adding non-package dependency {fullpath.name} --
 ADD {relpath} {destpath}"""
@@ -1320,7 +1320,7 @@ RUN set -ex && \\
                 '[build-system]' \\
                 'requires = ["setuptools>=61"]' \\
                 'build-backend = "setuptools.build_meta"'; do \\
-        echo "$line" >> /deps/__outer_{fullpath.name}/pyproject.toml; \\
+        echo "$line" >> /deps/outer-{fullpath.name}/pyproject.toml; \\
     done
 # -- End of non-package dependency {fullpath.name} --"""
         for fullpath, (relpath, destpath) in local_deps.faux_pkgs.items()
@@ -1423,7 +1423,7 @@ ADD {relpath} /deps/{name}
         if p in local_deps.real_pkgs:
             name = local_deps.real_pkgs[p][1]
         elif p in local_deps.faux_pkgs:
-            name = f"__outer_{p.name}"
+            name = f"outer-{p.name}"
         else:
             raise RuntimeError(f"Unknown additional context: {p}")
         additional_contexts[name] = str(p)
@@ -1436,9 +1436,28 @@ def node_config_to_docker(
     config: Config,
     base_image: str,
     api_version: Optional[str] = None,
+    install_command: Optional[str] = None,
+    build_command: Optional[str] = None,
+    build_context: Optional[str] = None,
 ) -> tuple[str, dict[str, str]]:
-    faux_path = f"/deps/{config_path.parent.name}"
-    install_cmd = _get_node_pm_install_cmd(config_path, config)
+    # Calculate paths for monorepo support
+    if build_context:
+        relative_workdir = _calculate_relative_workdir(config_path, build_context)
+        container_name = pathlib.Path(build_context).name
+        if relative_workdir:
+            faux_path = f"/deps/{container_name}/{relative_workdir}"
+        else:
+            faux_path = f"/deps/{container_name}"
+    else:
+        # Backward compatibility: use the original behavior
+        faux_path = f"/deps/{config_path.parent.name}"
+
+    # Use custom install command or auto-detect
+    if install_command:
+        install_cmd = install_command
+    else:
+        install_cmd = _get_node_pm_install_cmd(config_path, config)
+
     image_str = docker_tag(config, base_image, api_version)
 
     env_vars: list[str] = []
@@ -1465,20 +1484,35 @@ def node_config_to_docker(
 
     env_vars.append(f"ENV LANGSERVE_GRAPHS='{json.dumps(config['graphs'])}'")
 
+    # For monorepo support, we need to handle install and build commands differently
+    if build_context:
+        # Monorepo case: install from root, build from config directory
+        container_root = f"/deps/{pathlib.Path(build_context).name}"
+        install_step = f"RUN cd {container_root} && {install_cmd}"
+
+        if build_command:
+            build_step = f"RUN cd {faux_path} && {build_command}"
+        else:
+            build_step = 'RUN (test ! -f /api/langgraph_api/js/build.mts && echo "Prebuild script not found, skipping") || tsx /api/langgraph_api/js/build.mts'
+    else:
+        # Original behavior: everything happens in the same directory
+        install_step = f"RUN cd {faux_path} && {install_cmd}"
+        build_step = 'RUN (test ! -f /api/langgraph_api/js/build.mts && echo "Prebuild script not found, skipping") || tsx /api/langgraph_api/js/build.mts'
+
     docker_file_contents = [
         f"FROM {image_str}",
         "",
         os.linesep.join(config["dockerfile_lines"]),
         "",
-        f"ADD . {faux_path}",
+        f"ADD . {faux_path if not build_context else container_root}",
         "",
-        f"RUN cd {faux_path} && {install_cmd}",
+        install_step,
         "",
         os.linesep.join(env_vars),
         "",
         f"WORKDIR {faux_path}",
         "",
-        'RUN (test ! -f /api/langgraph_api/js/build.mts && echo "Prebuild script not found, skipping") || tsx /api/langgraph_api/js/build.mts',
+        build_step,
     ]
 
     return os.linesep.join(docker_file_contents), {}
@@ -1526,16 +1560,42 @@ def docker_tag(
     return f"{base_image}:{full_tag}"
 
 
+def _calculate_relative_workdir(config_path: pathlib.Path, build_context: str) -> str:
+    """Calculate the relative path from build context to langgraph.json directory."""
+    config_dir = config_path.parent.resolve()
+    build_context_path = pathlib.Path(build_context).resolve()
+
+    try:
+        relative_path = config_dir.relative_to(build_context_path)
+        return str(relative_path) if str(relative_path) != "." else ""
+    except ValueError as _:
+        raise ValueError(
+            f"Configuration file {config_path} is not under the build context {build_context}. "
+            f"Please run the command from a directory that contains your langgraph.json file, "
+        ) from None
+
+
 def config_to_docker(
     config_path: pathlib.Path,
     config: Config,
     base_image: Optional[str] = None,
     api_version: Optional[str] = None,
+    install_command: Optional[str] = None,
+    build_command: Optional[str] = None,
+    build_context: Optional[str] = None,
 ) -> tuple[str, dict[str, str]]:
     base_image = base_image or default_base_image(config)
 
     if config.get("node_version") and not config.get("python_version"):
-        return node_config_to_docker(config_path, config, base_image, api_version)
+        return node_config_to_docker(
+            config_path,
+            config,
+            base_image,
+            api_version,
+            install_command,
+            build_command,
+            build_context,
+        )
 
     return python_config_to_docker(config_path, config, base_image, api_version)