Files
app/backend/fluksio/sdk/client.py
T
stroblmeandClaude Fable 5 a38e2745eb Add a Python SDK: flows declared in your own repository
A data scientist keeps their code where it is and decorates it: `@node`
declares a function's ports beside the function, `Flow(name, nodes=[...])`
says which of them make a flow, and `use(fn, wire=..., **settings)` rebinds
one for a single flow. `fluksio sync` uploads the document plus a generated
import shim per node, so the store still holds a complete, runnable,
git-versioned definition while the code it imports stays theirs.

`fluksio login|run|runs` and `flow.submit().wait()` are the client half, over
the run endpoints that already existed. Runs record the user repository's
commit beside the store's, so "what code produced this number" is answerable
on the side that now holds the code.

- `fluksio/sdk/`: ports, decorators, the flow builder and its checks, the shim
  generator, an HTTP client and sync. Standard library only at import, so
  `from fluksio import node` in a training script pulls in no engine.
- `FlowDef.origin` marks a flow code-defined; `Run.origin_commit` carries the
  repository's commit; `POST /modules/refresh` retires the workers without an
  install, which every sync calls — a worker holds the imported package in
  memory, so an edit to it is invisible until the process goes.
- The canvas shows a generated body read-only and names the repository to edit
  instead; a body edited there stops the next sync rather than being discarded.
- The worker's reporter carries inert `Port`, `node`, `use` and `Flow`, since
  the shim imports a module whose first line declares them.
- `examples/myresearch` is the worked example, `make sync-example` uploads it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012ue1tkFWB1bcGy3aWhCKpU
2026-08-23 20:16:08 +02:00

412 lines
14 KiB
Python

"""Talking to an engine: uploading declared flows, and running them.
Two halves of one job. :func:`sync` puts what the decorators declared into the
flow store; :class:`Client` submits runs and reads back what they produced, so
an experiment is started and inspected from the same script that defines it.
"""
from __future__ import annotations
import json
import os
import subprocess
import time
from collections.abc import Iterable
from pathlib import Path
from typing import Any
from fluksio.sdk import MARKER, Flow, SyncError
__all__ = ["Client", "RunHandle", "SyncReport", "config_path", "login", "sync"]
API = "/api/v1"
#: A run is over when it reaches one of these.
DONE = frozenset({"ok", "error", "cancelled", "abandoned"})
def config_path() -> Path:
"""Where ``fluksio login`` leaves the engine it talked to."""
base = os.environ.get("XDG_CONFIG_HOME") or str(Path.home() / ".config")
return Path(base) / "fluksio" / "client.json"
def _stored() -> dict[str, str]:
path = config_path()
if not path.exists():
return {}
try:
data = json.loads(path.read_text())
except ValueError:
return {}
return data if isinstance(data, dict) else {}
class ApiError(Exception):
"""The engine refused, with what it said."""
def __init__(self, status: int, detail: Any) -> None:
super().__init__(f"{status}: {detail}")
self.status = status
self.detail = detail
class Conflict(ApiError):
"""Someone else saved in between — the 409 the optimistic lock answers."""
def __init__(self, detail: Any) -> None:
super().__init__(409, detail)
self.current_version = 0
if isinstance(detail, dict):
self.current_version = int(detail.get("current_version") or 0)
class Client:
"""An authenticated engine, addressed over its HTTP API."""
def __init__(
self, url: str = "", token: str = "", http: Any = None, timeout: float = 30.0
) -> None:
stored = _stored()
self.url = url or os.environ.get("FLUKSIO_URL") or stored.get("url") or ""
self.token = (
token or os.environ.get("FLUKSIO_TOKEN") or stored.get("token") or ""
)
if http is None:
if not self.url:
raise SyncError(
"No engine to talk to. Run `fluksio login --url http://…`, or "
"set FLUKSIO_URL and FLUKSIO_TOKEN."
)
import httpx
http = httpx.Client(base_url=self.url, timeout=timeout)
self.http = http
if self.token:
self.http.headers["Authorization"] = f"Bearer {self.token}"
# -- plumbing ----------------------------------------------------------
def _call(self, method: str, path: str, **kwargs: Any) -> Any:
response = self.http.request(method, f"{API}{path}", **kwargs)
if response.status_code == 409:
raise Conflict(_detail(response))
if response.status_code >= 400:
raise ApiError(response.status_code, _detail(response))
if response.status_code == 204 or not response.content:
return None
return response.json()
# -- flows -------------------------------------------------------------
def get_flow(self, name: str) -> dict[str, Any] | None:
"""The stored flow, draft included, or ``None`` if there is none."""
try:
result: dict[str, Any] = self._call("GET", f"/flows/{name}")
except ApiError as exc:
if exc.status == 404:
return None
raise
return result
def put_flow(self, document: dict[str, Any]) -> dict[str, Any]:
result: dict[str, Any] = self._call(
"PUT", f"/flows/{document['name']}", json=document
)
return result
def get_source(self, flow: str, node: str) -> str:
result = self._call("GET", f"/flows/{flow}/nodes/{node}/source")
return str(result.get("code", ""))
def put_source(self, flow: str, node: str, code: str) -> dict[str, Any]:
result: dict[str, Any] = self._call(
"PUT", f"/flows/{flow}/nodes/{node}/source", json={"code": code}
)
return result
def publish(self, name: str, version: int) -> dict[str, Any]:
result: dict[str, Any] = self._call(
"POST", f"/flows/{name}/publish", json={"version": version}
)
return result
def refresh_modules(self) -> None:
"""Retire the engine's workers, so the next run imports the code as it is."""
self._call("POST", "/modules/refresh")
# -- runs --------------------------------------------------------------
def submit(
self, flow: str, params: dict[str, Any] | None = None, seed: int | None = None
) -> RunHandle:
row = self._call(
"POST", f"/runs/flows/{flow}", json={"params": params or {}, "seed": seed}
)
return RunHandle(self, row["id"], row)
def run(self, run_id: str) -> dict[str, Any]:
result: dict[str, Any] = self._call("GET", f"/runs/{run_id}")
return result
def runs(self, flow: str = "", limit: int = 20, **filters: Any) -> Any:
query = {"limit": limit, **filters}
if flow:
query["flow"] = flow
return self._call("GET", "/runs", params=query)
def metrics(self, run_id: str, name: str = "", stride: int = 1) -> Any:
query: dict[str, Any] = {"stride": stride}
if name:
query["name"] = name
return self._call("GET", f"/runs/{run_id}/metrics", params=query)
def compare(self, ids: Iterable[str], metric: str) -> Any:
return self._call(
"GET",
"/runs/series/compare",
params={"ids": ",".join(ids), "metric": metric},
)
def cancel(self, run_id: str) -> Any:
return self._call("POST", f"/runs/{run_id}/cancel")
def download(self, digest: str) -> bytes:
response = self.http.request("GET", f"{API}/artifacts/{digest}")
if response.status_code >= 400:
raise ApiError(response.status_code, _detail(response))
return bytes(response.content)
def _detail(response: Any) -> Any:
try:
body = response.json()
except ValueError:
return response.text
return body.get("detail", body) if isinstance(body, dict) else body
class RunHandle:
"""One run, and the answers it accumulates."""
def __init__(self, client: Client, run_id: str, row: dict[str, Any]) -> None:
self.client = client
self.id = run_id
self._row = row
def refresh(self) -> RunHandle:
self._row = self.client.run(self.id)
return self
@property
def status(self) -> str:
return str(self._row.get("status", ""))
@property
def done(self) -> bool:
return self.status in DONE
@property
def result(self) -> dict[str, Any]:
"""What the flow's outputs held when it finished."""
result = self._row.get("result")
return result if isinstance(result, dict) else {}
@property
def artifacts(self) -> list[dict[str, Any]]:
rows = self._row.get("artifacts")
return rows if isinstance(rows, list) else []
def wait(self, timeout: float = 0.0, poll: float = 1.0) -> RunHandle:
"""Block until the run is over, or ``timeout`` seconds have passed."""
deadline = time.monotonic() + timeout if timeout else 0.0
while True:
self.refresh()
if self.done:
return self
if deadline and time.monotonic() > deadline:
raise TimeoutError(f"run {self.id} is still {self.status}")
time.sleep(poll)
def metrics(self, name: str = "", stride: int = 1) -> list[dict[str, Any]]:
"""A streamed port's whole series — a run's metrics are its outputs."""
points: list[dict[str, Any]] = self.client.metrics(self.id, name, stride)
return points
def download(self, name: str) -> bytes:
"""The bytes of an artifact this run produced."""
for row in self.artifacts:
if row.get("name") == name:
return self.client.download(str(row["digest"]))
have = ", ".join(str(row.get("name")) for row in self.artifacts) or "none"
raise KeyError(f"run {self.id} has no artifact '{name}' (it has {have})")
def __getitem__(self, key: str) -> Any:
return self._row[key]
def __repr__(self) -> str:
return f"RunHandle({self.id!r}, status={self.status!r})"
def login(url: str, email: str, password: str, timeout: float = 30.0) -> str:
"""Exchange credentials for a token and remember the engine."""
import httpx
response = httpx.post(
f"{url.rstrip('/')}{API}/login/access-token",
data={"username": email, "password": password},
timeout=timeout,
)
if response.status_code >= 400:
raise ApiError(response.status_code, _detail(response))
token = str(response.json()["access_token"])
path = config_path()
path.parent.mkdir(parents=True, exist_ok=True)
path.write_text(json.dumps({"url": url.rstrip("/"), "token": token}, indent=2))
path.chmod(0o600)
return token
# ---------------------------------------------------------------------------
# sync
# ---------------------------------------------------------------------------
class SyncReport:
"""What one flow's sync did, for the CLI to print."""
def __init__(self, flow: str) -> None:
self.flow = flow
self.created = False
self.changed: list[str] = []
self.published = False
@property
def unchanged(self) -> bool:
return not self.created and not self.changed
def __repr__(self) -> str:
return f"SyncReport({self.flow!r}, changed={self.changed})"
def origin_of(repo: str) -> dict[str, Any]:
"""Where this flow came from, so a run can name the code that produced it."""
commit, dirty = "", False
if repo:
head = _git(repo, "rev-parse", "HEAD")
if head is not None:
commit = head
dirty = bool(_git(repo, "status", "--porcelain"))
return {"kind": "python", "repo": repo, "commit": commit, "dirty": dirty}
def _git(repo: str, *args: str) -> str | None:
try:
result = subprocess.run(
["git", "-C", repo, *args], capture_output=True, text=True, timeout=10
)
except (OSError, subprocess.SubprocessError):
return None
return result.stdout.strip() if result.returncode == 0 else None
def repo_root(start: str | Path) -> str:
"""The git repository a path sits in, or its directory if there is none."""
directory = Path(start).resolve()
if directory.is_file():
directory = directory.parent
found = _git(str(directory), "rev-parse", "--show-toplevel")
return found or str(directory)
def sync(
flows: Iterable[Flow],
client: Client,
*,
repo: str = "",
origin: dict[str, Any] | None = None,
publish: bool = True,
force: bool = False,
) -> list[SyncReport]:
"""Put declared flows into the store, refusing to overwrite canvas work.
The order matters: the document first, so the nodes it names exist, then
each node's generated body, then one publish. Both writes no-op on
identical content, so a second sync with nothing changed commits nothing.
"""
stamp = origin if origin is not None else origin_of(repo)
reports = []
for target in flows:
reports.append(_sync_one(target, client, stamp, publish=publish, force=force))
# Always, even when nothing here changed. A worker holds the imported
# package in `sys.modules` for as long as it lives, so an edit to the
# caller's own code is invisible until the process is retired — and that
# edit is invisible to this function too, since it changes no shim and no
# document. Refusing to refresh on a "no-op" sync would skip exactly the
# case the refresh exists for.
client.refresh_modules()
return reports
def _sync_one(
target: Flow,
client: Client,
origin: dict[str, Any],
*,
publish: bool,
force: bool,
) -> SyncReport:
report = SyncReport(target.name)
stored = client.get_flow(target.name)
version = 1
if stored is None:
report.created = True
else:
definition = stored.get("definition") or {}
version = int(definition.get("version") or 1)
if not force:
_refuse_on_drift(client, target, definition)
saved = client.put_flow(target.document(origin) | {"version": version})
stored_version = int((saved.get("definition") or {}).get("version") or version)
if report.created or stored_version != version:
# The store bumps the version only when the content actually changed,
# so this is its own no-op detection rather than a second guess at it.
report.changed.append("flow")
version = stored_version
for node_id, code in target.shims().items():
if not report.created and client.get_source(target.name, node_id) == code:
continue
client.put_source(target.name, node_id, code)
report.changed.append(node_id)
if publish and (client.get_flow(target.name) or {}).get("has_draft"):
client.publish(target.name, version)
report.published = True
return report
def _refuse_on_drift(client: Client, target: Flow, definition: dict[str, Any]) -> None:
"""Stop before overwriting work that was done somewhere else.
Two ways a stored flow is not ours to replace: it was drawn on the canvas
and has no origin at all, or one of its node bodies no longer carries the
line saying it was generated — which means somebody edited the code there.
"""
if not definition.get("origin"):
raise SyncError(
f"flow '{target.name}' was not created by sync, so replacing it would "
"discard whoever drew it. Rename yours, or pass --force."
)
for stored_node in definition.get("nodes") or []:
node_id = str(stored_node.get("id"))
try:
code = client.get_source(target.name, node_id)
except ApiError:
continue
if code and not code.startswith(MARKER):
raise SyncError(
f"node '{target.name}.{node_id}' was edited on the canvas, and "
"syncing would throw that edit away. Copy it out, or pass --force."
)