stack-orchestrator/stack_orchestrator/build/fetch_containers.py
David Boreham da1ff609fe fetch-images command (#768)
Implementation of a command to fetch pre-built images from a remote registry, complementing the --push-images option already present on build-containers.

The two subcommands used together allow a stack to be deployed without needing to built its images, provided they have been already built and pushed to the specified container image registry.

This implementation simply picks the newest image with the right name and platform (matches against the platform Python is running on, so watch out for scenarios where Python is an x86 binary on M1 macs).

Reviewed-on: cerc-io/stack-orchestrator#768
Co-authored-by: David Boreham <david@bozemanpass.com>
Co-committed-by: David Boreham <david@bozemanpass.com>
2024-02-27 15:15:08 +00:00

181 lines
7.8 KiB
Python

# Copyright © 2024 Vulcanize
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http:#www.gnu.org/licenses/>.
import click
from dataclasses import dataclass
import json
import platform
from python_on_whales import DockerClient
from python_on_whales.components.manifest.cli_wrapper import ManifestCLI, ManifestList
from python_on_whales.utils import run
import requests
from typing import List
from stack_orchestrator.opts import opts
from stack_orchestrator.util import include_exclude_check, error_exit
from stack_orchestrator.build.build_util import get_containers_in_scope
# Experimental fetch-container command
@dataclass
class RegistryInfo:
registry: str
registry_username: str
registry_token: str
# Extending this code to support the --verbose option, cnosider contributing upstream
# https://github.com/gabrieldemarmiesse/python-on-whales/blob/master/python_on_whales/components/manifest/cli_wrapper.py#L129
class ExtendedManifestCLI(ManifestCLI):
def inspect_verbose(self, x: str) -> ManifestList:
"""Returns a Docker manifest list object."""
json_str = run(self.docker_cmd + ["manifest", "inspect", "--verbose", x])
return json.loads(json_str)
def _local_tag_for(container: str):
return f"{container}:local"
# See: https://docker-docs.uclv.cu/registry/spec/api/
# Emulate this:
# $ curl -u "my-username:my-token" -X GET "https://<container-registry-hostname>/v2/cerc-io/cerc/test-container/tags/list"
# {"name":"cerc-io/cerc/test-container","tags":["202402232130","202402232208"]}
def _get_tags_for_container(container: str, registry_info: RegistryInfo) -> List[str]:
# registry looks like: git.vdb.to/cerc-io
registry_parts = registry_info.registry.split("/")
url = f"https://{registry_parts[0]}/v2/{registry_parts[1]}/{container}/tags/list"
if opts.o.debug:
print(f"Fetching tags from: {url}")
response = requests.get(url, auth=(registry_info.registry_username, registry_info.registry_token))
if response.status_code == 200:
tag_info = response.json()
if opts.o.debug:
print(f"container tags list: {tag_info}")
tags_array = tag_info["tags"]
return tags_array
else:
error_exit(f"failed to fetch tags from image registry, status code: {response.status_code}")
def _find_latest(candidate_tags: List[str]):
# Lex sort should give us the latest first
sorted_candidates = sorted(candidate_tags)
if opts.o.debug:
print(f"sorted candidates: {sorted_candidates}")
return sorted_candidates[0]
def _filter_for_platform(container: str,
registry_info: RegistryInfo,
tag_list: List[str]) -> List[str] :
filtered_tags = []
this_machine = platform.machine()
# Translate between Python platform names and docker
if this_machine == "x86_64":
this_machine = "amd64"
if opts.o.debug:
print(f"Python says the architecture is: {this_machine}")
docker = DockerClient()
docker.login(registry_info.registry, registry_info.registry_username, registry_info.registry_token)
for tag in tag_list:
remote_tag = f"{registry_info.registry}/{container}:{tag}"
manifest_cmd = ExtendedManifestCLI(docker.client_config)
manifest = manifest_cmd.inspect_verbose(remote_tag)
if opts.o.debug:
print(f"manifest: {manifest}")
image_architecture = manifest["Descriptor"]["platform"]["architecture"]
if opts.o.debug:
print(f"image_architecture: {image_architecture}")
if this_machine == image_architecture:
filtered_tags.append(tag)
if opts.o.debug:
print(f"Tags filtered for platform: {filtered_tags}")
return filtered_tags
def _get_latest_image(container: str, registry_info: RegistryInfo):
all_tags = _get_tags_for_container(container, registry_info)
tags_for_platform = _filter_for_platform(container, registry_info, all_tags)
latest_tag = _find_latest(tags_for_platform)
return f"{container}:{latest_tag}"
def _fetch_image(tag: str, registry_info: RegistryInfo):
docker = DockerClient()
docker.login(registry_info.registry, registry_info.registry_username, registry_info.registry_token)
remote_tag = f"{registry_info.registry}/{tag}"
if opts.o.debug:
print(f"Attempting to pull this image: {remote_tag}")
docker.image.pull(remote_tag)
def _exists_locally(container: str):
docker = DockerClient()
return docker.image.exists(_local_tag_for(container))
def _add_local_tag(remote_tag: str, registry: str, local_tag: str):
docker = DockerClient()
docker.image.tag(f"{registry}/{remote_tag}", local_tag)
@click.command()
@click.option('--include', help="only fetch these containers")
@click.option('--exclude', help="don\'t fetch these containers")
@click.option("--force-local-overwrite", is_flag=True, default=False, help="Overwrite a locally built image, if present")
@click.option("--image-registry", required=True, help="Specify the image registry to fetch from")
@click.option("--registry-username", required=True, help="Specify the image registry username")
@click.option("--registry-token", required=True, help="Specify the image registry access token")
@click.pass_context
def command(ctx, include, exclude, force_local_overwrite, image_registry, registry_username, registry_token):
'''EXPERIMENTAL: fetch the images for a stack from remote registry'''
registry_info = RegistryInfo(image_registry, registry_username, registry_token)
# Generate list of target containers
stack = ctx.obj.stack
containers_in_scope = get_containers_in_scope(stack)
for container in containers_in_scope:
local_tag = _local_tag_for(container)
if include_exclude_check(container, include, exclude):
if opts.o.debug:
print(f"Processing: {container}")
# For each container, attempt to find the latest of a set of
# images with the correct name and platform in the specified registry
image_to_fetch = _get_latest_image(container, registry_info)
if opts.o.debug:
print(f"Fetching: {image_to_fetch}")
_fetch_image(image_to_fetch, registry_info)
# Now check if the target container already exists exists locally already
if (_exists_locally(container)):
if not opts.o.quiet:
print(f"Container image {container} already exists locally")
# if so, fail unless the user specified force-local-overwrite
if (force_local_overwrite):
# In that case remove the existing :local tag
if not opts.o.quiet:
print(f"Warning: overwriting local tag from this image: {container} because "
"--force-local-overwrite was specified")
else:
if not opts.o.quiet:
print(f"Skipping local tagging for this image: {container} because that would "
"overwrite an existing :local tagged image, use --force-local-overwrite to do so.")
# Tag the fetched image with the :local tag
_add_local_tag(image_to_fetch, image_registry, local_tag)
else:
if opts.o.verbose:
print(f"Excluding: {container}")