Containers

Containers, like Docker, are a way to package software and its dependencies into a standardized unit for software development. Containers are lightweight, standalone, and executable software packages that include everything needed to run an application: code, runtime, system tools, system libraries, and settings.

Untrusted Code Execution

If you are planning to execute code generated by an LLM, you should treat it as untrusted and use containers to isolate the execution environment.

Requirements

GenAIScript uses Docker to orchestrate the containers.

• Install docker

start a container

Start by creating and starting a new container. GenAIScript will pull the container image on demand and will remove the container when it is no longer needed.

const container = await host.container()

Custom image

By default, the container uses the python:alpine image, which provides a minimal python environment. You can change the image using the image option.

const container = await host.container({ image: "node:20" })

Building images

Use docker build to create reusable images.

You can build a custom image from a GitHub repository with a single command in your scripts.

const repo = "codelion/optillm" // GitHub repository = image name
const branch = "main"
const dir = "."
await host.exec(
    `docker build -t ${repo} https://github.com/${repo}.git#${branch}:${dir}`
)

then use repo as your image name

const container = await host.container({ image: repo, ... })

Disable auto-purge

By default, the container is removed when it is no longer needed. You can disable this behavior using the persistent option.

const container = await host.container({ persistent: true })

Enable network

By default, the container network is disabled and web requests won’t work. This is the safest solution; if you need to install additional packages, it is recommended to create an image with all the necessary software enabled.

You can enable network access using networkEnabled.

const container = await host.container({ networkEnabled: true })

Port bindings

You can bind container ports to host ports and access web servers running in the container.

For example, this configuration will map the host 8088 port to 80 on the container and you will be able to access a local web server using http://localhost:8088/.

const container = await host.container({
    networkEnabled: true,
    ports: {
        containerPort: "80/tcp",
        hostPort: 8088,
    }, // array also supported
})

Then

Run a command

You can run a command in the container using the exec method. It returns the exit code, standard output and error streams.

const { stdout } = await container.exec("python", ["--version"])

Read and write files

The container has a volume mounted in the host file system, which allows to read and write files to the container.

await container.writeText("hello.txt", "Hello, world!")
const content = await container.readText("hello.txt")

Copy files to container

You can also copy files from the host to the container.

// src/* -> ./src/*
await container.copyTo("src/**", ".")

Disconnect network

If you created the container with network enabled, you can disconnect the network to isolate the container.

await container.disconnect()

Using containers in tools

The containerized tools guide shows how to use containers in tools to handle untrusted text securely.