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Make client-side cancellation work over the 2026 transports (#3046)

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Max 2026-07-02 19:21:04 +01:00 • committed by GitHub
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83
tests/interaction/_requirements.py
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@ -474,6 +474,25 @@ REQUIREMENTS: dict[str, Requirement] = {
"never reused within the session."
),
),
"protocol:request-id:caller-supplied": Requirement(
source="sdk",
behavior=(
"A caller can supply the id of a request it sends, so the id is known before any response "
"arrives; subscriptions/listen streams are demultiplexed by exactly that id."
),
note=(
f"The demux-by-listen-request-id obligation is the spec's "
f"({SPEC_2026_BASE_URL}/basic/patterns/subscriptions#receiving-notifications); supplying the "
"id up front is the SDK surface that makes it satisfiable."
),
added_in="2026-07-28",
deferred=(
"No public API surface yet: the capability exists at the dispatcher seam "
"(CallOptions['request_id'], unit-tested there), but ClientSession.send_request does not "
"expose it. The public consumer arrives with the client-side listen driver (Client.listen), "
"whose interaction tests will exercise it end to end."
),
),
"protocol:notifications:no-response": Requirement(
source=f"{SPEC_BASE_URL}/basic#notifications",
behavior=(
@ -484,14 +503,32 @@ REQUIREMENTS: dict[str, Requirement] = {
"protocol:cancel:abort-signal": Requirement(
source=f"{SPEC_BASE_URL}/basic/utilities/cancellation#cancellation-flow",
behavior=(
"Cancelling an in-flight request through the client API sends notifications/cancelled with "
"the request id and fails the local call."
"Abandoning an in-flight request client-side (cancelling the task awaiting it) cancels the "
"request itself: the server-side handler stops and the session serves later requests "
"normally."
),
deferred=(
"Not implemented in the SDK: there is no public client-side API to cancel an in-flight "
"request; cancellation requires hand-constructing the notification (which is how "
"protocol:cancel:in-flight exercises the receiving side)."
note=(
"The per-transport wire spelling (frame vs response-stream close) is pinned separately by "
"protocol:cancel:stream-frame and the client-transport:http:cancel-* pair."
),
arm_exclusions=(
ArmExclusion(
reason="requires-session",
transport="streamable-http-stateless",
note=(
"The 2025-era cancel frame POSTs on a fresh per-request transport that shares no "
"in-flight state with the blocked request, so the handler is never interrupted."
),
),
),
),
"protocol:cancel:abort-scoped": Requirement(
source=f"{SPEC_BASE_URL}/basic/utilities/cancellation#behavior-requirements",
behavior=(
"Abandoning one in-flight request cancels only that request: a concurrent request on the "
"same connection keeps running and returns its result."
),
arm_exclusions=(ArmExclusion(reason="requires-session", transport="streamable-http-stateless"),),
),
"protocol:cancel:handler-abort-propagates": Requirement(
source=f"{SPEC_BASE_URL}/basic/utilities/cancellation#behavior-requirements",
@ -550,6 +587,16 @@ REQUIREMENTS: dict[str, Requirement] = {
ArmExclusion(reason="server-initiated-request", spec_version="2026-07-28"),
),
),
"protocol:cancel:stream-frame": Requirement(
source=f"{SPEC_2026_BASE_URL}/basic/patterns/cancellation#transport-specific-cancellation",
behavior=(
"On stream (stdio-shaped) wires at 2026-07-28, abandoning an in-flight request sends exactly "
"one notifications/cancelled naming its request id - streams keep the frame spelling of "
"cancellation that streamable HTTP dropped."
),
added_in="2026-07-28",
note="Exercised over the in-memory stream pair, the same dual-era wire stdio serves.",
),
"protocol:cancel:unknown-id-ignored": Requirement(
source=f"{SPEC_BASE_URL}/basic/utilities/cancellation#error-handling",
behavior=(
@ -3256,6 +3303,30 @@ REQUIREMENTS: dict[str, Requirement] = {
transports=("streamable-http",),
note="Only observable over HTTP: Accept is an HTTP request header.",
),
"client-transport:http:cancel-closes-stream": Requirement(
source=f"{SPEC_2026_BASE_URL}/basic/transports/streamable-http#cancellation",
behavior=(
"At 2026-07-28, abandoning an in-flight request closes that request's own POST stream and "
"posts nothing further: no notifications/cancelled reaches the server (the revision defines "
"no client-to-server notifications), and the server treats the disconnect as cancellation "
"of exactly that request."
),
transports=("streamable-http",),
added_in="2026-07-28",
supersedes=("client-transport:http:cancel-posts-frame",),
note="HTTP-only by nature: the response stream that closing constitutes the signal is an HTTP exchange.",
),
"client-transport:http:cancel-posts-frame": Requirement(
source=f"{SPEC_BASE_URL}/basic/utilities/cancellation#cancellation-flow",
behavior=(
"At 2025-era revisions, abandoning an in-flight request POSTs exactly one "
"notifications/cancelled naming its request id."
),
transports=("streamable-http",),
removed_in="2026-07-28",
superseded_by="client-transport:http:cancel-closes-stream",
note="HTTP-only by nature: pins that the frame travels as its own POST on the legacy HTTP wire.",
),
"client-transport:http:concurrent-streams": Requirement(
source="sdk",
behavior="Multiple concurrent POST-initiated SSE streams each deliver their response to the right caller.",