kub-cli is a thin Python client that exposes stable native commands for KUB tools while executing the real logic inside container images.
kub-datasetkub-simulatekub-dashboardkub-img
The wrapper does not reimplement dataset/simulation/dashboard business logic. It resolves configuration, builds runtime commands, and executes them.
License: Apache-2.0.
Why this exists
kub-cli provides a consistent command-line UX across laptops, workstations, CI, and HPC environments.
Runtime model
Supported runtimes:
apptainerdockerauto
Policy:
- Apptainer remains the preferred runtime for HPC / Slurm / MPI-oriented execution.
- Docker is supported for local/workstation/CI usage.
autoprefers Apptainer when configured and available, then falls back to Docker.
Default behavior:
- Default runtime is
auto. - In
auto, kub-cli checks Apptainer first, then Docker. - If neither runtime is installed, kub-cli reports how to install them.
Installation
From source
Editable install for development
Quick start
Set runtime and images:
export KUB_RUNTIME=auto export KUB_IMAGE_DOCKER=ghcr.io/feelpp/ktirio-urban-building:master export KUB_IMAGE_APPTAINER=/path/to/ktirio-urban-building.sif
Then use wrapper commands:
kub-simulate --runtime docker -- run case.yaml kub-dataset --runtime apptainer -- push ./data kub-dashboard --runtime auto -- serve ./results
Command behavior
For Apptainer runtime:
apptainer run [common options] --app <wrapped-app> <local-sif-image> [forwarded args...]
For Docker runtime:
docker run --rm [common options] <docker-image> <wrapped-app> [forwarded args...]
Mappings:
kub-dataset->kub-datasetkub-simulate->kub-simulatekub-dashboard->kub-dashboard
All non-wrapper arguments are forwarded transparently to the in-container app.
Wrapper options
Available on all three wrapper commands:
--runtime {auto,apptainer,docker}--image IMAGE--bind SRC:DST(repeatable)--pwd PATH--runner PATH--apptainer-flag FLAG(repeatable)--docker-flag FLAG(repeatable)--env KEY=VALUE(repeatable)--cemdb-root PATH(host path mounted to/cemdb; default current directory)--dry-run--verbose / --no-verbose--show-config--version
Wrapper options must be placed before the forwarded in-container command arguments.
By default, kub-cli mounts the current working directory to /cemdb.
If --cemdb-root PATH is provided and PATH does not exist, kub-cli creates it.
kub-cli also creates PATH/.kub and sets HOME=/cemdb plus
KUB_CONFIG=/cemdb/.kub/config.toml by default so dataset config files are writable in containers.
By default, kub-cli also sets container working directory to /cemdb (override with --pwd).
If an inner command argument includes --cemdb-root <host-path>, kub-cli rewrites it to
--cemdb-root /cemdb and mounts the provided host path to /cemdb.
For kub-simulate, kub-cli injects --config /cemdb/.kub-simulate.toml unless an explicit
inner --config is already provided, so simulation profiles live in the mounted /cemdb context.
When a local cemdb/ directory exists, kub-cli mirrors this config to
cemdb/.kub-simulate.toml for local visibility and portability.
For kub-simulate, kub-cli prepares Slurm command support inside the containerized wrapper:
- if host
sbatch/srunare available, kub-cli bridges them into/cemdb/.kub-cli/host-binand prepends this path to containerPATH - if host Slurm commands are unavailable, kub-cli injects lightweight no-op shims in
/cemdb/.kub-cli/shimsfor inner--dry-runandpreprocessflows so local script generation/preview still works without a Slurm installation - for
kub-simulateApptainer-oriented profiles (for example--profile apptainer-slurm), kub-cli also exposes a host Apptainer executable path into the container when available. For Apptainer runtime, kub-cli forwards wrapper-managed env vars withAPPTAINERENV_*/SINGULARITYENV_*to ensure in-containerPATH/config overrides apply. For Docker runtime, kub-cli runs with host UID:GID by default to avoid bind-mount permission issues; override with explicit--docker-flag --user ...if needed. Forkub-dashboardon Docker runtime, kub-cli enables host networking by default (docker run --network host) so dashboard ports are directly reachable on the host. Override with explicit--docker-flag --network ...if you need a different mode. For Apptainer runtime, kub-cli uses standard host networking behavior.
Use -- to force all remaining arguments to be forwarded:
kub-simulate --runtime docker -- --help kub-dataset --cemdb-root ./cemdb -- pull-simulator --version 0.2.0 --force
Image model
Canonical upstream reference is Docker/OCI.
Example Docker image:
ghcr.io/feelpp/ktirio-urban-building:master
Derived Apptainer remote source:
oras://ghcr.io/feelpp/ktirio-urban-building:master-sif
Default image references used when no explicit image is configured:
- Docker:
ghcr.io/feelpp/ktirio-urban-building:master - Apptainer remote source:
oras://ghcr.io/feelpp/ktirio-urban-building:master-sif
For wrapper execution with Apptainer runtime, kub-cli first checks for a local
./kub-master.sif in the current directory. If present, it is used.
For backward compatibility, ./ktirio-urban-building-master.sif is also recognized.
Otherwise kub-cli runs from the ORAS reference above.
When a local Apptainer image does not define --app kub-dataset|kub-simulate|kub-dashboard,
kub-cli automatically falls back to apptainer exec <image> <app> ....
Other tags are supported (for example pr-<nnn>), e.g.:
- Docker:
ghcr.io/feelpp/ktirio-urban-building:pr-456 - Apptainer source:
oras://ghcr.io/feelpp/ktirio-urban-building:pr-456-sif
Important:
- For Apptainer download/pull, use
oras://.... - Do not use
docker://...for Apptainer pulls in this workflow.
kub-img
kub-img is the image utility command used by kub-cli internals for image pull/info workflows.
Subcommands:
kub-img pull [SOURCE] [--runtime ...] [--image ...]kub-img info [--runtime ...] [--image ...] [--json]kub-img apps(Apptainer runtime)kub-img path
Default behavior:
kub-img pull --runtime apptainerderives source asoras://ghcr.io/feelpp/ktirio-urban-building:master-sif- If no local Apptainer destination is configured, kub-cli uses
./kub-master.sifin the current directory --runtime autoprefers Apptainer when available inPATH, then Docker
Examples:
# Docker pull kub-img pull --runtime docker --image ghcr.io/feelpp/ktirio-urban-building:master # Apptainer pull with ORAS source kub-img pull oras://ghcr.io/feelpp/ktirio-urban-building:master-sif \ --runtime apptainer \ --image ./ktirio-urban-building.sif # Apptainer pull with defaults (source and local destination auto-resolved) kub-img pull --runtime apptainer # Runtime-aware image info kub-img info --runtime docker --image ghcr.io/feelpp/ktirio-urban-building:master --json kub-img info --runtime apptainer --image ./ktirio-urban-building.sif
Configuration
Precedence (highest to lowest):
- CLI options
- Environment variables
- Project config:
.kub-cli.tomlin current working directory - User config:
~/.config/kub-cli/config.toml - Built-in defaults
Precedence behavior details:
- Scalar settings (
runtime,workdir,runner, image values,verbose) are last-wins. - List settings (
bind,apptainer_flags,docker_flags) are additive merged across layers with de-duplication while preserving order.
Environment variables
KUB_RUNTIME:auto|apptainer|dockerKUB_IMAGE_DOCKER: Docker image referenceKUB_IMAGE_APPTAINER: Apptainer image path (local SIF); optional override for default local destinationKUB_IMAGE: legacy generic image fallback (backward compatibility)KUB_BIND: additional binds, comma- or semicolon-separatedKUB_WORKDIR: runtime working directoryKUB_APP_RUNNER: generic runner overrideKUB_APPTAINER_RUNNER: Apptainer runner overrideKUB_DOCKER_RUNNER: Docker runner overrideKUB_VERBOSE: boolean (true/false,1/0,yes/no,on/off)KUB_APPTAINER_FLAGS: extra Apptainer flags (shell-split)KUB_DOCKER_FLAGS: extra Docker flags (shell-split)
Config file format
You can place config at:
~/.config/kub-cli/config.toml.kub-cli.toml
Keys may be top-level or under [kub_cli].
[kub_cli] runtime = "auto" workdir = "/work" verbose = false [kub_cli.image] docker = "ghcr.io/feelpp/ktirio-urban-building:master" apptainer = "./ktirio-urban-building.sif" [kub_cli.env] OMP_NUM_THREADS = "8"
Backward compatibility
kub-cli keeps compatibility with existing Apptainer-centric usage:
- Existing
KUB_IMAGEstill works as a fallback image setting. - Existing Apptainer command flow remains unchanged when runtime resolves to
apptainer. - Existing wrapper UX and argument forwarding semantics are preserved.
For explicit multi-runtime setups, prefer KUB_IMAGE_DOCKER and KUB_IMAGE_APPTAINER.
Troubleshooting
- Docker runtime selected but Docker missing: install Docker or set
--runner. - Apptainer runtime selected but Apptainer missing: install Apptainer or set
--runner. - No image configured for selected runtime: set
--image, runtime-specific env vars, or config. - Need to inspect resolved command: use
--dry-run.
Development
uv venv .venv . .venv/bin/activate uv pip install -e '.[dev]' pytest
Smoke tests with fake container runners:
pytest -q tests/test_smoke_fake_runtimes.py
Version bumping for maintainers:
# bump patch/minor/major from pyproject version kub-cli bump patch kub-cli bump minor kub-cli bump major # explicit target version kub-cli bump patch --to 0.2.0 # preview only kub-cli bump patch --dry-run
kub-cli bump updates pyproject.toml, fallback src/kub_cli/__init__.py, and rotates CHANGELOG.md by converting ## Unreleased into the new released section.
Release versioning policy:
kub-cliuses SemVer (MAJOR.MINOR.PATCH).- Release tags must be
vMAJOR.MINOR.PATCH. - The tag version must match
project.versioninpyproject.toml.
PyPI publishing via GitHub environment:
- Workflow:
.github/workflows/publish.yml - Trigger: publish a GitHub Release (SemVer tag, for example
v0.2.0) or runworkflow_dispatch. - Publish job uses GitHub
environment: pypiand OpenID Connect trusted publishing (no PyPI API token needed in GitHub secrets). - Publishing is restricted to the official repository
feelpp/kub-cli.
One-time setup:
- In GitHub repository settings, create environment
pypi. - In PyPI Organizations, ensure project
kub-clibelongs to organizationfeelpp. - In the
kub-cliPyPI project settings (under organizationfeelpp), add a trusted publisher bound to:- owner/repository:
feelpp/kub-cli - workflow:
publish.yml - environment:
pypi
- owner/repository:
- Ensure the first trusted release tag already exists in the repository.
Release steps:
# 1) bump version in source tree kub-cli bump patch # 2) commit + tag matching SemVer version git add pyproject.toml src/kub_cli/__init__.py git commit -m "Release 0.1.1" git tag v0.1.1 git push origin main --tags # 3) publish GitHub Release (this triggers PyPI workflow) gh release create v0.1.1 --generate-notes
The workflow validates the tag format and checks that it matches pyproject.toml before building and publishing to PyPI.
License
This project is licensed under the Apache License 2.0. See LICENSE.