Implementation:Bentoml BentoML Docker Backend

Knowledge Sources	Bentoml_BentoML
Domains	Container, OCI
Last Updated	2026-02-13 15:00 GMT

Overview

Implements the standard Docker container builder backend for BentoML, extending the OCIBuilder base class to build OCI images using the docker build command with BuildKit support.

Description

The docker module provides the standard Docker backend implementation for BentoML's container build system. It extends the OCIBuilder base class and exports the standard backend interface:

• BUILDKIT_SUPPORT -- Set to True since Docker 18.09+ supports BuildKit.
• ENV -- Default environment variables: DOCKER_BUILDKIT=1 (enable BuildKit) and DOCKER_SCAN_SUGGEST=false (suppress scan suggestions).
• find_binary() -- Locates the docker executable using shutil.which. This function is also reused by the Buildx backend.
• health() -- Verifies Docker is installed, then checks the server version (parsed via regex) to ensure it is >= 18.09 for BuildKit compatibility. Respects the DOCKER_BUILDKIT environment variable.
• construct_build_args() -- Builds the CLI argument list for docker build. Supports the following options:
  • add_host -- Host-to-IP mappings (dict or tuple)
  • build_arg -- Build-time variables (dict or tuple)
  • cache_from -- Cache source specification (string or dict)
  • isolation -- Windows container isolation mode (default/process/hyperv); warns on non-Windows
  • label -- Image labels (dict or tuple)
  • output -- Custom output configuration (string or dict)
  • secret -- Build secrets (string or dict)
  • Additional keyword arguments are passed through with underscores replaced by hyphens.

Usage

Use this backend as the default container builder for building Docker images with BentoML's containerization workflow.

Code Reference

Source Location

• Repository: Bentoml_BentoML
• File: src/bentoml/_internal/container/docker.py
• Lines: 1-106

Signature

BUILDKIT_SUPPORT = True
ENV = {"DOCKER_BUILDKIT": "1", "DOCKER_SCAN_SUGGEST": "false"}

def find_binary() -> str | None: ...
def health() -> bool: ...
def construct_build_args(
    *,
    context_path: PathType = ".",
    add_host: dict[str, str] | ArgType = None,
    build_arg: dict[str, str] | ArgType = None,
    cache_from: str | dict[str, str] | ArgType = None,
    isolation: t.Literal["default", "process", "hyperv"] | None = None,
    label: dict[str, str] | ArgType = None,
    output: str | dict[str, str] | ArgType = None,
    secret: str | dict[str, str] | ArgType = None,
    **kwargs: t.Any,
) -> Arguments: ...

Import

from bentoml._internal.container import docker

I/O Contract

Inputs

Name	Type	Required	Description
context_path	PathType	No	Build context directory (default: ".")
add_host	dict or tuple	No	Extra host-to-IP mappings
build_arg	dict or tuple	No	Build-time variables
cache_from	str or dict	No	Cache source specification
isolation	Literal["default","process","hyperv"]	No	Windows container isolation mode
label	dict or tuple	No	Image labels
output	str or dict	No	Output configuration
secret	str or dict	No	Build secrets

Outputs

Name	Type	Description
Arguments	Arguments	Constructed CLI argument list for docker build command
bool	bool	Health check result
str or None	str or None	Path to docker binary (from find_binary)

Usage Examples

from bentoml._internal.container import docker

# Check if docker is available and healthy
if docker.health():
    # Construct build arguments
    args = docker.construct_build_args(
        context_path="/path/to/project",
        build_arg={"VERSION": "1.0", "ENV": "production"},
        label={"maintainer": "team@example.com"},
        cache_from="myrepo/cache:latest",
        tag=("myimage:latest",),
    )

Related Pages

• Implementation:Bentoml_BentoML_OCIBuilder_Base
• Implementation:Bentoml_BentoML_Buildx_Backend