sonata-tasks

Reusable, product-independent tasks for sonata-engine. The base installation contains command execution contracts and common command-line tool tasks. Provider and transport integrations are installed through optional extras.

The base catalogue includes Kubernetes namespace ownership, port forwarding, Pod and OCI image inspection, and Minikube profile preflight in sonata_tasks.kubectl, sonata_tasks.imagetools, and sonata_tasks.minikube. sonata_tasks.vm.logged provides bounded VM command output with a complete log copied to the host. Callers supply their own executor, VM provider, and product-specific image checks.

sonata_tasks.containerd inspects a caller-owned container and its image using caller-supplied commands, then checks the runtime image reference and published manifest digest. The caller controls namespace, rootless session, and evidence storage; the task has no NanoLab or recipe dependency.

With the shell extra, sonata_tasks.shell.SubprocessShell streams stdout and stderr to the active workflow sink, including when no output listener is provided. An explicit listener receives each line as well; command results still contain the complete output and exit code.

sonata_tasks.process also exports OwnedCommandRunner, OwnedCommandResult and run_owned_command for bounded local Linux commands. They require procfs, pidfds and subreaper support. An isolated supervisor owns and reaps descendants, including children that create their own sessions, without changing the caller's subreaper state or signaling unrelated processes. Output goes to an exclusive log file; optional framed summaries share the same byte budget.

import os
import sys
from pathlib import Path
from threading import Event

from sonata_tasks.process import run_owned_command

result = run_owned_command(
    [sys.executable, "-c", "print('ordinary application command')"],
    cwd=Path.cwd(),
    env=os.environ,
    log_path=Path("command.log"),
    timeout_s=30,
    cancelled=Event(),
    output_limit_bytes=1024 * 1024,
)
print(result)

The result records exit status, cancellation, timeout, quota exhaustion, forced stops and confirmed reaping. A zero exit code alone is insufficient to declare success. OwnedCommandRunner.stop(timeout_s) requires at least 0.1 seconds for descendant cleanup; a runner executes only once. Linux restrictions apply to this API, while the existing managed_process_resource remains portable.

The implementation in sonata_tasks.owned_process uses only the standard library. A worker that cannot install the catalogue may copy that module from its installed distribution, preserving the distribution version and verifying the source digest. It does not need the workflow engine at worker runtime.

sonata_tasks.artifacts provides exclusive bounded artifact directories, serialized JSONL append, immutable JSON/raw publication and streaming file descriptors. Acquisition requires directory flock; publication uses hard links, fsync and no-follow append flags. Configurable markers share the same directory lock during acquisition and cannot create independent concurrent owners; the filesystem must support those operations. A fresh writer refuses existing contents, and its ownership marker remains after close. Default accounting charges this writer's own bytes, including partially failed appends. No files are excluded by name. The codec limits each JSON record to 1 MiB; raw writes are bounded by the total quota.

An ordinary command audit can also account for a log written outside the writer:

import os
import sys
from pathlib import Path
from tempfile import TemporaryDirectory
from threading import Event

from sonata_tasks.artifacts import ArtifactWriter, describe_artifact, read_records
from sonata_tasks.process import run_owned_command

with TemporaryDirectory() as temporary:
    root = Path(temporary) / "audit"
    writer = ArtifactWriter(
        root,
        1024 * 1024,
        measure_usage=lambda: sum(
            p.stat().st_size
            for p in root.rglob("*")
            if p.is_file() and not p.is_symlink()
        ),
    )
    result = run_owned_command(
        [sys.executable, "-c", "print('ordinary application command')"],
        cwd=root,
        env=os.environ,
        log_path=root / "command.log",
        timeout_s=30,
        cancelled=Event(),
        output_limit_bytes=1024,
    )
    writer.append(
        "commands",
        {
            "returncode": result.returncode,
            "reaped": result.reaped,
            "errors": list(result.errors),
            "log": describe_artifact(root / "command.log"),
        },
    )
    writer.close()
    print(list(read_records(root / "commands.jsonl")))

Callers must serialize producers sharing a measure_usage callback; a writer's lock only protects its own writes. An explicit reserve_bytes is available to write_json("summary.json", value, use_reserve=True), with no privileged filename or default reservation. owner_marker selects a safe hidden filename, defaulting to .artifact-owner. read_records yields valid objects and raises a distinct IncompleteRecordError with path and line_number for a final record without a newline. Complete malformed, non-object, non-finite or oversized records raise ArtifactCorruptionError; clients decide how to report missing evidence.

sonata_tasks.sources captures a Git working tree for repeatable local builds: tracked files (including deletions), nonignored untracked files, executable modes and safe relative symlinks. Already dangling internal links are preserved; links outside the checkout or to existing excluded inputs, cycles and submodules fail. This differs from the committed-source remote transfer in sonata_tasks.archive.

from pathlib import Path

from sonata_tasks.artifacts import ArtifactWriter
from sonata_tasks.sources import capture_source_snapshot, materialize_snapshot

writer = ArtifactWriter(Path("/tmp/application-snapshot"), 16 * 1024 * 1024)
try:
    snapshot = capture_source_snapshot(
        Path("/path/to/application"), writer, max_bytes=128 * 1024 * 1024
    )
    writer.write_json("receipt.json", {"fingerprint": snapshot.fingerprint})
finally:
    writer.close()
workspace = materialize_snapshot(snapshot, Path("/tmp/application-build"))

The caller owns/closes storage and chooses its receipt schema. Capture creates tree and source-manifest.jsonl; failed capture retains partial evidence. max_bytes bounds input bytes, including symlink target bytes; the writer's quota separately bounds the manifest, with a 100000-entry inventory limit. SourceSnapshot seals the manifest and inventory with bare-hex SHA-256 identities. verify_snapshot rejects changed inputs/manifest; materialize_snapshot verifies before and after copying to a fresh independent workspace. source_entry supports checking original inputs in a workspace that also contains generated outputs. The caller must control its filesystem namespace and serialize concurrent writes; repeated inventory checks detect ordinary concurrent changes, without making capture atomic against hostile filesystem mutation. Verification ignores empty directories and binds file/link modes, paths and contents, not directory metadata.

sonata_tasks.buildx.buildx_builder_resource can acquire a private application builder with exclusive=True. It refuses existing names, assigns a unique owner node, bootstraps the builder and returns its name. use=False leaves the client's selected builder intact. Default reuse and optional replacement remain available.

from sonata_engine import TaskInputs
from sonata_tasks.buildx import buildx_builder_resource
from sonata_tasks.execution.local import LocalCommandTaskExecutor
from sonata_tasks.execution.models import CommandOptions

inputs = TaskInputs.empty()
builder = buildx_builder_resource(
    name="application-build",
    executor=LocalCommandTaskExecutor(),
    exclusive=True,
    use=False,
    options=CommandOptions(env={"DOCKER_CONFIG": "/tmp/application-docker"}),
)
name = builder.acquire(inputs)
try:
    print(f"Build application images with docker buildx build --builder {name}")
finally:
    builder.release(inputs, name)

Exclusive cleanup verifies the original single node and docker-container driver before removing the builder. Failed creation and validation compensate partial state; the original exception retains cleanup failures as notes. An explicit owner_node lets a caller record the identity. After failed acquisition, release(inputs, "application-build") can retry unresolved cleanup; it does nothing after confirmed removal or absence. Foreign replacement, added nodes or unavailable inspection prevent removal and report an error. Callers serialize other mutations of the same Buildx client store during inspection and removal; Docker's CLI has no atomic compare-and-delete operation. Emulation installation and platform requirements remain caller policy.

A failed buildx rm may erase the client record while leaving the daemon alive. After such a failure, record absence remains unresolved and requires operator reconciliation. A retry succeeds if the same owned builder is still inspectable and its removal succeeds; an empty listing alone cannot confirm daemon cleanup.

Compose resources can clear previous project state before deployment when the caller explicitly owns an isolated project name:

from pathlib import Path
from sonata_engine import Workflow
from sonata_tasks.command import CommandTask
from sonata_tasks.compose import DockerComposeProject, docker_compose_resource
from sonata_tasks.execution.local import LocalCommandTaskExecutor

project = DockerComposeProject(
    name="application-integration-test",
    file=Path("compose.yaml"),
    ready_url="http://127.0.0.1:8080/health",
    build=False,
)
resource = docker_compose_resource(
    project,
    executor=LocalCommandTaskExecutor(),
    pre_clean=True,
    remove_volumes=True,
    remove_orphans=True,
)
workflow = Workflow("application-integration-test")
workflow.add(
    CommandTask(
        title="Check application",
        argv=("curl", "-fsS", project.ready_url),
        executor=LocalCommandTaskExecutor(),
    ),
    requires=(resource,),
)
workflow.run()

By default pre_clean=False: acquisition only deploys and waits for readiness. Both pre-clean and final teardown use the same optional volume/orphan flags. Failed acquisition performs best-effort teardown and retains cleanup failures as exception notes. The caller chooses the namespace and removal policy; the resource does not verify exclusive ownership of existing Compose state. It returns the original project object, including subclass fields, and accepts resource dependencies through requires.

VM executors can translate local project directories to an explicitly selected remote checkout. Supply both roots when configuring an injected VM runner:

from pathlib import Path
from sonata_tasks.execution.adapters import VmCommandTaskExecutor
from sonata_tasks.execution.models import CommandOptions, CommandTaskSpec


def run_remote_build(vm_runner):
    executor = VmCommandTaskExecutor(
        vm_runner,
        target_key="application-build-vm",
        local_root=Path("/workspace/application"),
        remote_root="/srv/application/releases/test",
    )
    return executor.run(
        CommandTaskSpec(
            task_id="build",
            summary="Build application",
            argv=("make",),
            options=CommandOptions(cwd=Path("src"), env={"MODE": "test"}),
        )
    )

The runner receives /srv/application/releases/test/src as remote_dir. Absolute local directories must remain under the resolved local root; relative ones resolve against it. Parent-directory and symlink escapes, or simultaneous cwd and remote_dir, fail before calling the backend, including in dry runs. With no cwd, the original remote_dir passes through and the runner retains its defaults. Without mapping roots, local cwd remains unsupported. Remote roots are nonempty POSIX paths; relative roots retain the runner's meaning and are not canonicalized on the remote filesystem. Timeouts remain unsupported. The binding identity includes the target and both mapping roots, so changes to the destination invalidate command fingerprints. Enabling mapping also changes existing bindings once, which can cause previously journalled commands to rerun.

Pure measurement readers are available without optional integrations:

from sonata_tasks.k6 import k6_value, k6_values
from sonata_tasks.metrics import counter_delta, point_stats

summary = {"http_reqs": {"values": {"count": 12}}}
requests = k6_value(k6_values(summary, "http_reqs"), "http_reqs", "count")
observations = [
    {"timestamp": 1, "value": "10", "labels": {"job": "application"}},
    {"timestamp": 2, "value": "14", "labels": {"job": "application"}},
]
assert requests == 12
assert counter_delta(observations) == 4
assert point_stats(observations, counter=True)["delta"] == 4

k6_values accepts flat summary exports and nested handleSummary values. k6_value requires a finite nonnegative JSON number; the first present alias wins, even when malformed. Missing/invalid values raise ValueError. The standard checks and http_req_failed rate/value fields must be within 0..1. finite_number also accepts numeric strings, excluding booleans and nonfinite values, with optional nonnegative validation.

Counter deltas group complete string-to-string publisher labels and require two samples per publisher. Timestamped publisher samples are sorted; incomplete timestamps retain input order. A decrease contributes the new counter value. Invalid, missing or overflowing evidence returns None, while a constant counter returns zero. Statistics sum equal timestamps and allow negative gauges. Invalid values, sums or timestamp keys produce counts and invalid_points without statistics; an unavailable or overflowing delta is omitted. Timestamp keys must be hashable and consistently comparable, non-null/non-boolean and finite when numeric. Missing keys have distinct internal identities and cannot collide with observed keys; dates and units are not parsed. Callers choose metrics, counter classification, time windows and qualification policy.

sonata_tasks.credentials validates and stages private application files through any existing RemoteProvider. This base-only API needs POSIX current-user ownership, no-follow/nonblocking opens, and trusted providers with caller-controlled filesystem namespaces. Source files must be nonempty regular owner-readable files with no group/world permissions. Copies are 0600 inside 0700 directories; remote targets must support mktemp, chmod and rm. Names and prefix are public basenames, never credential contents.

from pathlib import Path

from sonata_tasks.credentials import stage_private_files, validate_private_file

source = validate_private_file(Path("service.key"))
with stage_private_files(provider, request, {"service-key": source}) as staged:
    directory, paths = staged
    configure_service(paths["service-key"])

The context removes both temporary locations on success and failure. Operational provider failures omit command output and exception messages. Body/programming exceptions retain their type after successful cleanup; CredentialCleanupError reports only the interrupted operation's type when cleanup fails. An invalid mktemp response is refused without guessing a directory to remove. The provider and caller remain responsible for protecting the remote filesystem namespace.

Frozen source archives

Use sonata_tasks.archive.stage_source_archive in an ordinary application to reuse an existing archive across targets. Supply expected_digest (64 hex characters, optionally prefixed with sha256:) to bind the consumed bytes to previous evidence. Local mismatches fail before any remote changes; the remote SHA-256 is checked before Python's data-filter extraction. Direct callers use remove_source_archive for normal release; failed staging compensates both remote paths and notes operational cleanup failures on the primary error.

from pathlib import Path
from sonata_tasks.archive import stage_source_archive, remove_source_archive

stage_source_archive(
    provider,
    request,
    archive=Path("application.tar"),
    expected_digest=application_digest,
    remote_archive="/srv/application-run/source.tar",
    remote_source_dir="/srv/application-run/source",
)
try:
    run_application("/srv/application-run/source")
finally:
    remove_source_archive(
        provider,
        request,
        remote_archive="/srv/application-run/source.tar",
        remote_source_dir="/srv/application-run/source",
    )

source_archive_resource(archive=path, expected_digest=digest, provider=provider, request=request, remote_archive=archive_path, remote_source_dir=source_path) offers the same frozen reuse as a workflow Resource. Use strict_cleanup=True to remove both remote paths and report unsuccessful release. Its existing Git-export mode rejects expected_digest without a frozen archive and still exports per acquisition, uses tar extraction and best-effort release by default. Frozen resources always release; local bytes remain caller-owned.

Targets need Python >=3.12 plus mkdir, rm and sha256sum. Safe extraction preserves file execute bits and sets directories to0755. The shared SOURCE_ARCHIVE_EXTRACT_SCRIPT provides identical extraction on a planning host. Reserve exclusive canonical absolute nonroot destinations: source and archive must not overlap. Providers and parent namespaces are trusted; callers coordinate concurrent writers. Cleanup cannot guarantee recovery after forced termination or a permanently unreachable target.

Captured Linux memory text

sonata_tasks.procfs provides ordinary, dependency-free parsers. They accept captured text on any platform and do not open procfs or collect from processes.

from sonata_tasks.procfs import parse_kib_field, parse_smaps

rss = parse_kib_field("VmRSS: 12 kB\n", "VmRSS")  # 12288 bytes
missing = parse_kib_field(None, "Pss")  # None, distinct from zero
memory = parse_smaps("1000-2000 rw-p 0 00:00 0\nSize: 4 kB\nRss: 2 kB\nPss: 1 kB\n")
assert memory["anonymous"]["rss"] == 2048

Smaps results contain the complete mapping inventory and byte totals for anonymous, file, shared_memory and unknown VMA backing. A file mapping with anonymous copy-on-write pages remains file-backed; these totals do not attribute every resident page or allocator ownership. Incomplete/malformed mapping records and duplicate required Size/Rss/Pss fields raise ValueError instead of yielding partial totals. Selected KiB fields likewise reject malformed or duplicate values while leaving missing fields as None. Callers bound captured input, select fields and choose any size thresholds.