langchain/libs/cli/langchain_cli/namespaces/app.py

359 lines
11 KiB
Python

"""
Manage LangChain apps
"""
import shutil
import subprocess
import sys
from pathlib import Path
from typing import Dict, List, Optional, Tuple
import typer
from typing_extensions import Annotated
from langchain_cli.utils.events import create_events
from langchain_cli.utils.git import (
DependencySource,
copy_repo,
parse_dependencies,
update_repo,
)
from langchain_cli.utils.packages import (
LangServeExport,
get_langserve_export,
get_package_root,
)
from langchain_cli.utils.pyproject import (
add_dependencies_to_pyproject_toml,
remove_dependencies_from_pyproject_toml,
)
REPO_DIR = Path(typer.get_app_dir("langchain")) / "git_repos"
app_cli = typer.Typer(no_args_is_help=True, add_completion=False)
@app_cli.command()
def new(
name: Annotated[
Optional[str],
typer.Argument(
help="The name of the folder to create",
),
] = None,
*,
package: Annotated[
Optional[List[str]],
typer.Option(help="Packages to seed the project with"),
] = None,
pip: Annotated[
Optional[bool],
typer.Option(
"--pip/--no-pip",
help="Pip install the template(s) as editable dependencies",
is_flag=True,
),
] = None,
noninteractive: Annotated[
bool,
typer.Option(
"--non-interactive/--interactive",
help="Don't prompt for any input",
is_flag=True,
),
] = False,
):
"""
Create a new LangServe application.
"""
has_packages = package is not None and len(package) > 0
if noninteractive:
if name is None:
raise typer.BadParameter("name is required when --non-interactive is set")
name_str = name
pip_bool = bool(pip) # None should be false
else:
name_str = (
name if name else typer.prompt("What folder would you like to create?")
)
if not has_packages:
package = []
package_prompt = "What package would you like to add? (leave blank to skip)"
while True:
package_str = typer.prompt(
package_prompt, default="", show_default=False
)
if not package_str:
break
package.append(package_str)
package_prompt = (
f"{len(package)} added. Any more packages (leave blank to end)?"
)
has_packages = len(package) > 0
pip_bool = False
if pip is None and has_packages:
pip_bool = typer.confirm(
"Would you like to install these templates into your environment "
"with pip?",
default=False,
)
# copy over template from ../project_template
project_template_dir = Path(__file__).parents[1] / "project_template"
destination_dir = Path.cwd() / name_str if name_str != "." else Path.cwd()
app_name = name_str if name_str != "." else Path.cwd().name
shutil.copytree(project_template_dir, destination_dir, dirs_exist_ok=name == ".")
readme = destination_dir / "README.md"
readme_contents = readme.read_text()
readme.write_text(readme_contents.replace("__app_name__", app_name))
pyproject = destination_dir / "pyproject.toml"
pyproject_contents = pyproject.read_text()
pyproject.write_text(pyproject_contents.replace("__app_name__", app_name))
# add packages if specified
if has_packages:
add(package, project_dir=destination_dir, pip=pip_bool)
typer.echo(f'\n\nSuccess! Created a new LangChain app under "./{app_name}"!\n\n')
typer.echo("Next, enter your new app directory by running:\n")
typer.echo(f" cd ./{app_name}\n")
typer.echo("Then add templates with commands like:\n")
typer.echo(" langchain app add extraction-openai-functions")
typer.echo(
" langchain app add git+ssh://git@github.com/efriis/simple-pirate.git\n\n"
)
@app_cli.command()
def add(
dependencies: Annotated[
Optional[List[str]], typer.Argument(help="The dependency to add")
] = None,
*,
api_path: Annotated[List[str], typer.Option(help="API paths to add")] = [],
project_dir: Annotated[
Optional[Path], typer.Option(help="The project directory")
] = None,
repo: Annotated[
List[str],
typer.Option(help="Install templates from a specific github repo instead"),
] = [],
branch: Annotated[
List[str], typer.Option(help="Install templates from a specific branch")
] = [],
pip: Annotated[
bool,
typer.Option(
"--pip/--no-pip",
help="Pip install the template(s) as editable dependencies",
is_flag=True,
prompt="Would you like to `pip install -e` the template(s)?",
),
],
):
"""
Adds the specified template to the current LangServe app.
e.g.:
langchain app add extraction-openai-functions
langchain app add git+ssh://git@github.com/efriis/simple-pirate.git
"""
parsed_deps = parse_dependencies(dependencies, repo, branch, api_path)
project_root = get_package_root(project_dir)
package_dir = project_root / "packages"
create_events(
[{"event": "serve add", "properties": dict(parsed_dep=d)} for d in parsed_deps]
)
# group by repo/ref
grouped: Dict[Tuple[str, Optional[str]], List[DependencySource]] = {}
for dep in parsed_deps:
key_tup = (dep["git"], dep["ref"])
lst = grouped.get(key_tup, [])
lst.append(dep)
grouped[key_tup] = lst
installed_destination_paths: List[Path] = []
installed_destination_names: List[str] = []
installed_exports: List[LangServeExport] = []
for (git, ref), group_deps in grouped.items():
if len(group_deps) == 1:
typer.echo(f"Adding {git}@{ref}...")
else:
typer.echo(f"Adding {len(group_deps)} templates from {git}@{ref}")
source_repo_path = update_repo(git, ref, REPO_DIR)
for dep in group_deps:
source_path = (
source_repo_path / dep["subdirectory"]
if dep["subdirectory"]
else source_repo_path
)
pyproject_path = source_path / "pyproject.toml"
if not pyproject_path.exists():
typer.echo(f"Could not find {pyproject_path}")
continue
langserve_export = get_langserve_export(pyproject_path)
# default path to package_name
inner_api_path = dep["api_path"] or langserve_export["package_name"]
destination_path = package_dir / inner_api_path
if destination_path.exists():
typer.echo(
f"Folder {str(inner_api_path)} already exists. " "Skipping...",
)
continue
copy_repo(source_path, destination_path)
typer.echo(f" - Downloaded {dep['subdirectory']} to {inner_api_path}")
installed_destination_paths.append(destination_path)
installed_destination_names.append(inner_api_path)
installed_exports.append(langserve_export)
if len(installed_destination_paths) == 0:
typer.echo("No packages installed. Exiting.")
return
try:
add_dependencies_to_pyproject_toml(
project_root / "pyproject.toml",
zip(installed_destination_names, installed_destination_paths),
)
except Exception:
# Can fail if user modified/removed pyproject.toml
typer.echo("Failed to add dependencies to pyproject.toml, continuing...")
try:
cwd = Path.cwd()
installed_destination_strs = [
str(p.relative_to(cwd)) for p in installed_destination_paths
]
except ValueError:
# Can fail if the cwd is not a parent of the package
typer.echo("Failed to print install command, continuing...")
else:
if pip:
cmd = ["pip", "install", "-e"] + installed_destination_strs
cmd_str = " \\\n ".join(installed_destination_strs)
typer.echo(f"Running: pip install -e \\\n {cmd_str}")
subprocess.run(cmd, cwd=cwd)
chain_names = []
for e in installed_exports:
original_candidate = f'{e["package_name"].replace("-", "_")}_chain'
candidate = original_candidate
i = 2
while candidate in chain_names:
candidate = original_candidate + "_" + str(i)
i += 1
chain_names.append(candidate)
api_paths = [
str(Path("/") / path.relative_to(package_dir))
for path in installed_destination_paths
]
imports = [
f"from {e['module']} import {e['attr']} as {name}"
for e, name in zip(installed_exports, chain_names)
]
routes = [
f'add_routes(app, {name}, path="{path}")'
for name, path in zip(chain_names, api_paths)
]
t = (
"this template"
if len(chain_names) == 1
else f"these {len(chain_names)} templates"
)
lines = (
["", f"To use {t}, add the following to your app:\n\n```", ""]
+ imports
+ [""]
+ routes
+ ["```"]
)
typer.echo("\n".join(lines))
@app_cli.command()
def remove(
api_paths: Annotated[List[str], typer.Argument(help="The API paths to remove")],
*,
project_dir: Annotated[
Optional[Path], typer.Option(help="The project directory")
] = None,
):
"""
Removes the specified package from the current LangServe app.
"""
project_root = get_package_root(project_dir)
project_pyproject = project_root / "pyproject.toml"
package_root = project_root / "packages"
remove_deps: List[str] = []
for api_path in api_paths:
package_dir = package_root / api_path
if not package_dir.exists():
typer.echo(f"Package {api_path} does not exist. Skipping...")
continue
try:
pyproject = package_dir / "pyproject.toml"
langserve_export = get_langserve_export(pyproject)
typer.echo(f"Removing {langserve_export['package_name']}...")
shutil.rmtree(package_dir)
remove_deps.append(api_path)
except Exception:
pass
try:
remove_dependencies_from_pyproject_toml(project_pyproject, remove_deps)
except Exception:
# Can fail if user modified/removed pyproject.toml
typer.echo("Failed to remove dependencies from pyproject.toml.")
@app_cli.command()
def serve(
*,
port: Annotated[
Optional[int], typer.Option(help="The port to run the server on")
] = None,
host: Annotated[
Optional[str], typer.Option(help="The host to run the server on")
] = None,
app: Annotated[
Optional[str], typer.Option(help="The app to run, e.g. `app.server:app`")
] = None,
) -> None:
"""
Starts the LangServe app.
"""
# add current dir as first entry of path
sys.path.append(str(Path.cwd()))
app_str = app if app is not None else "app.server:app"
host_str = host if host is not None else "127.0.0.1"
import uvicorn
uvicorn.run(
app_str, host=host_str, port=port if port is not None else 8000, reload=True
)