Files

115 lines
5.0 KiB
Python

"""Input/output artifact transport kept separate from the daemon state machine."""
from __future__ import annotations
import hashlib
import http.client
import json
from pathlib import Path
from typing import Protocol
from urllib.parse import quote, urlsplit
from urllib.request import HTTPRedirectHandler, Request, build_opener
from .models import ClaimedTask, ProducedArtifact
def _origin(uri: str) -> tuple[str, str, int | None]:
parsed = urlsplit(uri)
scheme = parsed.scheme.lower()
default_port = {"http": 80, "https": 443}.get(scheme)
return scheme, (parsed.hostname or "").lower(), parsed.port or default_port
class _SameOriginAuthRedirectHandler(HTTPRedirectHandler):
"""Do not forward the coordinator token when a download changes origin."""
def __init__(self, coordinator_origin: tuple[str, str, int | None]) -> None:
super().__init__()
self.coordinator_origin = coordinator_origin
def redirect_request(self, req: Request, fp: object, code: int, msg: str, headers: object, newurl: str) -> Request | None:
redirected = super().redirect_request(req, fp, code, msg, headers, newurl)
if redirected and _origin(newurl) != self.coordinator_origin:
redirected.remove_header("Authorization")
return redirected
class ArtifactClient(Protocol):
def download(self, uri: str, destination: Path) -> None: ...
def upload(
self, task: ClaimedTask, worker_id: str, artifact: ProducedArtifact
) -> str: ...
class HttpArtifactClient:
"""Transfers artifacts through the coordinator without leaking credentials."""
def __init__(self, coordinator_url: str, timeout: float, bearer_token: str | None = None) -> None:
self.coordinator_url = coordinator_url.rstrip("/")
self.timeout = timeout
self.bearer_token = bearer_token
self.coordinator_origin = _origin(coordinator_url)
self._opener = build_opener(_SameOriginAuthRedirectHandler(self.coordinator_origin))
def download(self, uri: str, destination: Path) -> None:
destination.parent.mkdir(parents=True, exist_ok=True)
request = Request(uri, headers=self._auth_headers_for(uri))
with self._opener.open(request, timeout=self.timeout) as response, destination.open("wb") as target:
while chunk := response.read(1024 * 1024):
target.write(chunk)
def upload(self, task: ClaimedTask, worker_id: str, artifact: ProducedArtifact) -> str:
"""Stream one result artifact to the coordinator and return its stable URI."""
url = (
f"{self.coordinator_url}/tasks/{quote(task.task_id, safe='')}/artifacts/"
f"{quote(artifact.path.name, safe='')}"
)
parsed = urlsplit(url)
if parsed.scheme not in {"http", "https"} or not parsed.hostname:
raise ValueError("coordinator URL must be an absolute HTTP(S) URL")
connection_class = (
http.client.HTTPSConnection if parsed.scheme == "https" else http.client.HTTPConnection
)
connection = connection_class(parsed.hostname, parsed.port, timeout=self.timeout)
try:
path = parsed.path + (f"?{parsed.query}" if parsed.query else "")
connection.putrequest("PUT", path)
connection.putheader("Content-Type", artifact.content_type)
connection.putheader("Content-Length", str(artifact.path.stat().st_size))
connection.putheader("X-Worker-ID", worker_id)
connection.putheader("X-Task-Attempt", str(task.attempt))
for name, value in self._auth_headers_for(url).items():
connection.putheader(name, value)
connection.endheaders()
with artifact.path.open("rb") as source:
while chunk := source.read(1024 * 1024):
connection.send(chunk)
response = connection.getresponse()
body = response.read()
if not 200 <= response.status < 300:
raise RuntimeError(f"artifact upload rejected with status {response.status}")
if body:
try:
response_data = json.loads(body)
except json.JSONDecodeError as error:
raise RuntimeError("artifact upload returned invalid JSON") from error
response_uri = response_data.get("uri") if isinstance(response_data, dict) else None
if isinstance(response_uri, str) and response_uri:
return response_uri
return url
finally:
connection.close()
def _auth_headers_for(self, uri: str) -> dict[str, str]:
"""Only coordinator-owned URLs receive the coordinator bearer token."""
if self.bearer_token and _origin(uri) == self.coordinator_origin:
return {"Authorization": f"Bearer {self.bearer_token}"}
return {}
def sha256_file(path: Path) -> str:
digest = hashlib.sha256()
with path.open("rb") as source:
for chunk in iter(lambda: source.read(1024 * 1024), b""):
digest.update(chunk)
return digest.hexdigest()