PAGI-0.002008

Changes for version 0.002008 - 2026-09-01

Specification
- HTTP/WebSocket/SSE sub-spec 0.4 -> 0.5. These are new requirements, not clarifications, so $scope->{pagi}{spec_version} moves with them. The core spec is unchanged.
- The terminal response event is defined as what it asserts: the application's claim that the response is complete (RFC 9110 S6.1), which the server renders as the chunked terminator or END_STREAM. The existing prohibitions follow from that.
- The ban on synthesizing terminal framing binds every producer, not only the server. Middleware that buffers and re-emits a body MUST NOT complete an incomplete stream, nor derive an ETag, Content-Length, or other completeness-dependent metadata from the bytes it happened to see.
- Says which of the two signals answers which question: absence of the terminal event governs what may be forwarded or synthesized; disconnect_reason governs only whether to raise or log. The previous wording left it to inference, and every consumer inferred it the same way and wrong.
- A response body is either inline events or one file/fh event, never both. Mixing them leaves a body-transforming intermediary unable to honour the encoding it already declared; the server now fails such a send.
- An intermediary MUST examine the response head before transforming a body or attaching metadata derived from one, and MUST NOT invalidate what that head promised -- trailers => 1 commits the server to chunked framing, and a 206 body is a range rather than the representation.
- An intermediary re-emitting a buffered event MUST preserve its other keys, including more, whose default of 0 makes an omission an assertion of completeness.
What may break
- Sending a file/fh body after inline body bytes. Undefined before, so it worked; a conforming server now fails that send. Send the whole body inline instead, or put the leading bytes in the file.
- Relying on an intermediary to finish an incomplete response. Middleware may no longer synthesize a terminal event, ETag or Content-Length on an application's behalf, so such a response now stays observably incomplete.
- Middleware that transforms bodies without consulting the response head is now non-conforming, even where it happens to work.
- Not affected: complete responses, file/fh alone, inline streaming to completion.