workflows-vasp-other-languages

This repository holds the httk₂ VASP relaxation authored once per native language SDK of httk-workflow: Ada, C, C++, Fortran, Java, Perl, and Rust. Each directory is a self-contained workflow package, referenced directly by a git commit, like those of workflows-vasp. Every runner is a bridge client of the SDK in the installed httk-workflow, so it publishes the same protocol bytes as a Python or Bash runner.

Directory	Short name	Language
vasp-relax-ada	vasp.relax-ada	Ada 2012
vasp-relax-c	vasp.relax-c	C99
vasp-relax-cpp	vasp.relax-cpp	C++17
vasp-relax-fortran	vasp.relax-fortran	Fortran 2008
vasp-relax-java	vasp.relax-java	Java 17
vasp-relax-perl	vasp.relax-perl	Perl 5
vasp-relax-rust	vasp.relax-rust	Rust 2021

All seven share one shape: prepare stages the payload POSCAR (and INCAR, if present) into the workdir, run runs the configured VASP command under supervision and classifies the result, and publish copies the finished calculation into the job's data/ when the job sets publish_data. prepare uses each SDK's stage_input verb, so no runner copies files itself. They declare the same workflow semantics as vasp.relax (the same declaration.json, input structure and outputs relaxed_structure and total_energy), and each collect.py locates the CONTCAR and OUTCAR with record.result_file and reads them with the read_structure and read_total_energy helpers of httk.codes.vasp.collect from an installed httk-workflow-vasp (pip install httk-workflow-vasp). They are deliberately minimal starting points: the remedy ladder, derived INCAR tags, and POTCAR assembly of vasp.relax are not reimplemented here.

Job parameters

Every member is optional: poscar (default files/POSCAR), incar (default files/INCAR), timeout (default 86400), publish_data (default false), data_prefix (default vasp), and vasp_command, the VASP command as one whitespace-split argv string. The vasp.command workspace setting overrides vasp_command:

httk workspace settings set --key vasp.command --value 'srun vasp_std' WORKSPACE

These native-language runners call the generic run verb, which is not code-aware: it runs vasp.command exactly as given and never prepends the attempt's launch prefix (HTTK_WORKFLOW_LAUNCH). On a cluster without confinement the command must therefore include the site launcher, as above, and the runners do not run in parallel inside a confined attempt (manager.confine=bwrap). The Python and Bash VASP workflows in workflows-vasp add the launch prefix automatically.

By default the persistent workdir is the result. Pass --parameter publish_data=true to httk job new to also publish the files into data/ (below data_prefix).

Building

Every package except Perl declares [workflow.build]. It is built and registered for this platform class (uname -sm; Java bytecode has no platform tag) when it is installed into a workspace, before a manager runs its jobs, and rebuilt by name:

httk workflow install --workspace WORKSPACE ./vasp-relax-c
httk workflow build --workspace WORKSPACE vasp.relax-c

The build command is make, which compiles against the installed SDK in $HTTK_WORKFLOW_LANGUAGES_DIR/<language>, a variable httk workflow build exports. The Rust package copies the SDK crate to target/sdk first, since Cargo cannot expand an environment variable in a path dependency. Package publication transfers sources only, and no package carries a run bridge script: each manifest's [workflow.runner] command names what the manager runs. The compiled packages declare command = ["{artifacts}/relax"] (Java: ["java", "-cp", "{artifacts}/classes", "Relax"]), which the manager expands to the registered build. The Perl package needs no build: its command is ["perl", "{package}/relax.pl"], and the script loads the SDK from $HTTK_WORKFLOW_PERL_API.

Toolchains needed on the building machine, besides make:

Package	Toolchain
vasp-relax-ada	gnatmake (GNAT) and a C compiler (cc)
vasp-relax-c	a C compiler (cc)
vasp-relax-cpp	g++ and a C compiler (cc)
vasp-relax-fortran	gfortran and a C compiler (cc)
vasp-relax-java	a JDK 17+ (javac); running needs java
vasp-relax-perl	perl (no build)
vasp-relax-rust	cargo; the build is --offline with no crates.io dependencies

Reference a workflow by commit

A workflow is installed in a workspace before jobs of it are created; --install installs (and builds) it first:

httk job new --install --workflow 'git+https://github.com/httk/workflows-vasp-other-languages@<ref>#vasp-relax-c' --input structure=POSCAR

<ref> may be a commit, branch, or tag, or omitted for the default branch; it is canonicalized to the full commit hash the repository is cloned at, and the named subdirectory's httk_workflow.toml package is installed. Once installed, its short name (e.g. vasp.relax-c) also resolves.

Install as a plugin

httk plugin install 'git+https://github.com/httk/workflows-vasp-other-languages'

installs all seven workflow packages listed in httk_plugin.toml at once on this machine; each is still installed into a workspace (httk job new --install --workflow vasp.relax-c) before its jobs are created.

Testing

make test

runs pytest on tests/ against the installed httk-workflow and httk-workflow-vasp. Each language's end-to-end test installs (and so builds) its package into a workspace, runs one relaxation job through a real task manager with the mock VASP in tests/mock_vasp.py, and collects it; it is skipped when that language's toolchain is missing. HTTK_TEST_PROFILE=extended also runs each package with publish_data.