fed-sx-m1: Step 8d-dispatch-cap — capabilities_body_for + Accept-aware route + 13 tests

next/kernel/http_server.erl

@@ -10,7 +10,8 @@
          post_activity_response/0,
          validation_failed_response/0,
          cid_response/1,
-         accept_format/1, accept_format_from/1]).
+         accept_format/1, accept_format_from/1,
+         capabilities_body_for/1]).
 
 %% HTTP request router per design §16.1.
 %%
@@ -43,6 +44,11 @@ route(Req, Cfg) ->
     case {M, P} of
         {<<80,79,83,84>>, <<47,97,99,116,105,118,105,116,121>>} ->
             handle_post_activity(Req, Cfg);
+        {<<71,69,84>>,
+         <<47,46,119,101,108,108,45,107,110,111,119,110,
+           47,115,120,45,99,97,112,97,98,105,108,105,116,105,101,115>>} ->
+            F = accept_format_from(Req),
+            ok_response(capabilities_body_for(F));
         _ ->
             dispatch(M, P)
     end.
@@ -356,3 +362,30 @@ accept_format_from(Req) ->
                 not_found -> text
             end
     end.
+
+%% capabilities_body_for/1 — content-negotiated capability bodies.
+%% Each format returns a distinct byte sequence so dispatch can be
+%% observed end-to-end. Real serialisation (JSON-LD, dag-cbor, etc.)
+%% lands once the corresponding encoder BIFs are wired; v1 uses
+%% tagged stubs that are syntactically the right shape.
+capabilities_body_for(text) ->
+    capabilities_body();
+%% `{"caps":"fed-sx-m1"}\n` — 21 bytes
+capabilities_body_for(json) ->
+    <<123,34,99,97,112,115,34,58,34,
+      102,101,100,45,115,120,45,109,49,34,125,10>>;
+capabilities_body_for(activity_json) ->
+    %% Same payload as :json — the difference is the Content-Type
+    %% header (Step 8d-content-type follow-up); body shape matches.
+    capabilities_body_for(json);
+%% `(caps "fed-sx-m1")\n` — 19 bytes
+capabilities_body_for(sx) ->
+    <<40,99,97,112,115,32,34,
+      102,101,100,45,115,120,45,109,49,34,41,10>>;
+%% A minimal CBOR map: 0xA1 0x64 "caps" 0x69 "fed-sx-m1"
+%% A1 = map(1); 64 = text(4) "caps"; 69 = text(9) "fed-sx-m1"
+capabilities_body_for(cbor) ->
+    <<161,100,99,97,112,115,105,
+      102,101,100,45,115,120,45,109,49>>;
+capabilities_body_for(_) ->
+    capabilities_body().

next/tests/http_capabilities_format.sh

@@ -0,0 +1,133 @@
+#!/usr/bin/env bash
+# next/tests/http_capabilities_format.sh — Step 8d-dispatch-cap test.
+#
+# Proves Accept header dispatch end-to-end on the
+# /.well-known/sx-capabilities route. 12 cases.
+
+set -uo pipefail
+cd "$(git rev-parse --show-toplevel)"
+
+SX_SERVER="${SX_SERVER:-hosts/ocaml/_build/default/bin/sx_server.exe}"
+if [ ! -x "$SX_SERVER" ]; then
+  SX_SERVER="/root/rose-ash/hosts/ocaml/_build/default/bin/sx_server.exe"
+fi
+if [ ! -x "$SX_SERVER" ]; then
+  echo "ERROR: sx_server.exe not found." >&2
+  exit 1
+fi
+
+VERBOSE="${1:-}"
+PASS=0; FAIL=0; ERRORS=""
+TMPFILE=$(mktemp); trap "rm -f $TMPFILE" EXIT
+
+# Shared bindings for the test:
+#   AK = "accept" header key
+#   CapPath = capabilities path (looked up from the module)
+PRELUDE='AK = <<97,99,99,101,112,116>>, CapPath = http_server:capabilities_path(),'
+
+cat > "$TMPFILE" <<EPOCHS
+(epoch 1)
+(load "lib/erlang/tokenizer.sx")
+(load "lib/erlang/parser.sx")
+(load "lib/erlang/parser-core.sx")
+(load "lib/erlang/parser-expr.sx")
+(load "lib/erlang/parser-module.sx")
+(load "lib/erlang/transpile.sx")
+(load "lib/erlang/runtime.sx")
+(load "lib/erlang/vm/dispatcher.sx")
+
+(epoch 2)
+(eval "(get (erlang-load-module (file-read \"next/kernel/http_server.erl\")) :name)")
+
+;; capabilities_body_for(text) == capabilities_body()
+(epoch 10)
+(eval "(get (erlang-eval-ast \"http_server:capabilities_body_for(text) =:= http_server:capabilities_body()\") :name)")
+
+;; All format stubs are distinct
+(epoch 11)
+(eval "(get (erlang-eval-ast \"T = http_server:capabilities_body_for(text), J = http_server:capabilities_body_for(json), S = http_server:capabilities_body_for(sx), C = http_server:capabilities_body_for(cbor), (T =/= J) and (J =/= S) and (S =/= C) and (T =/= C)\") :name)")
+
+;; json body starts with '{' (123)
+(epoch 12)
+(eval "(get (erlang-eval-ast \"case http_server:capabilities_body_for(json) of <<123, _/binary>> -> ok; _ -> bad end\") :name)")
+
+;; sx body starts with '(' (40)
+(epoch 13)
+(eval "(get (erlang-eval-ast \"case http_server:capabilities_body_for(sx) of <<40, _/binary>> -> ok; _ -> bad end\") :name)")
+
+;; cbor body starts with 0xA1 (161) — map(1)
+(epoch 14)
+(eval "(get (erlang-eval-ast \"case http_server:capabilities_body_for(cbor) of <<161, _/binary>> -> ok; _ -> bad end\") :name)")
+
+;; activity_json shares its body with json
+(epoch 15)
+(eval "(get (erlang-eval-ast \"http_server:capabilities_body_for(activity_json) =:= http_server:capabilities_body_for(json)\") :name)")
+
+;; Unknown format falls back to text
+(epoch 16)
+(eval "(get (erlang-eval-ast \"http_server:capabilities_body_for(weird_format) =:= http_server:capabilities_body()\") :name)")
+
+;; Route with Accept: application/json -> json body
+(epoch 17)
+(eval "(get (erlang-eval-ast \"${PRELUDE} AV = <<97,112,112,108,105,99,97,116,105,111,110,47,106,115,111,110>>, Req = [{method, <<71,69,84>>}, {path, CapPath}, {headers, [{AK, AV}]}], R = http_server:route(Req), case R of [_, _, {body, B}] -> B =:= http_server:capabilities_body_for(json); _ -> false end\") :name)")
+
+;; Route with Accept: application/sx -> sx body
+(epoch 18)
+(eval "(get (erlang-eval-ast \"${PRELUDE} AV = <<97,112,112,108,105,99,97,116,105,111,110,47,115,120>>, Req = [{method, <<71,69,84>>}, {path, CapPath}, {headers, [{AK, AV}]}], R = http_server:route(Req), case R of [_, _, {body, B}] -> B =:= http_server:capabilities_body_for(sx); _ -> false end\") :name)")
+
+;; Route with Accept: application/cbor -> cbor body
+(epoch 19)
+(eval "(get (erlang-eval-ast \"${PRELUDE} AV = <<97,112,112,108,105,99,97,116,105,111,110,47,99,98,111,114>>, Req = [{method, <<71,69,84>>}, {path, CapPath}, {headers, [{AK, AV}]}], R = http_server:route(Req), case R of [_, _, {body, B}] -> B =:= http_server:capabilities_body_for(cbor); _ -> false end\") :name)")
+
+;; No Accept header -> text body
+(epoch 20)
+(eval "(get (erlang-eval-ast \"${PRELUDE} Req = [{method, <<71,69,84>>}, {path, CapPath}], R = http_server:route(Req), case R of [_, _, {body, B}] -> B =:= http_server:capabilities_body(); _ -> false end\") :name)")
+
+;; POST capabilities still 404
+(epoch 21)
+(eval "(get (erlang-eval-ast \"${PRELUDE} Req = [{method, <<80,79,83,84>>}, {path, CapPath}], case http_server:route(Req) of [{status, 404} | _] -> ok; _ -> bad end\") :name)")
+EPOCHS
+
+OUTPUT=$(timeout 60 "$SX_SERVER" < "$TMPFILE" 2>/dev/null)
+
+check() {
+  local epoch="$1" desc="$2" expected="$3"
+  local actual
+  actual=$(echo "$OUTPUT" | awk -v e="$epoch" '
+    $0 ~ "^\\(ok-len " e " " { getline; print; exit }
+    $0 ~ "^\\(ok " e " "     { print; exit }
+    $0 ~ "^\\(error " e " "  { print; exit }
+  ')
+  [ -z "$actual" ] && actual="<no output for epoch $epoch>"
+  if echo "$actual" | grep -qF -- "$expected"; then
+    PASS=$((PASS+1))
+    [ "$VERBOSE" = "-v" ] && echo "  ok $desc"
+  else
+    FAIL=$((FAIL+1))
+    ERRORS+="  FAIL [$desc] (epoch $epoch) expected: $expected | actual: $actual
+"
+  fi
+}
+
+check  2  "module load name"                  "http_server"
+check 10  "text format = existing body"       "true"
+check 11  "all format stubs distinct"         "true"
+check 12  "json body starts with '{'"         "ok"
+check 13  "sx body starts with '('"           "ok"
+check 14  "cbor body starts with 0xA1"        "ok"
+check 15  "activity_json == json body"        "true"
+check 16  "unknown format -> text"            "true"
+check 17  "Accept: json -> json body"         "true"
+check 18  "Accept: sx -> sx body"             "true"
+check 19  "Accept: cbor -> cbor body"         "true"
+check 20  "no Accept -> text body"            "true"
+check 21  "POST capabilities still 404"       "ok"
+
+TOTAL=$((PASS+FAIL))
+if [ $FAIL -eq 0 ]; then
+  echo "ok $PASS/$TOTAL next/tests/http_capabilities_format.sh passed"
+else
+  echo "FAIL $PASS/$TOTAL passed, $FAIL failed:"
+  echo "$ERRORS"
+fi
+[ $FAIL -eq 0 ]

plans/fed-sx-milestone-1.md

@@ -518,7 +518,8 @@ publish(ActorId, ActivityRequest) ->
 - [x] **8c-post-publish-srv** — gen_server wrapper around nx_kernel: `start_link/3`, named-process `publish/1`, `query/0`, `log_tip/0`, `with_projections/1`, `stop/0`. `next/tests/nx_kernel_server.sh` (11 cases). HTTP layer integration follows.
 - [x] **8c-post-publish-http** — POST `/activity` handler now calls `nx_kernel:publish/1` when the kernel process is registered; falls back to the existing stub when not. Success → 200 with `cid: <cid>\n` body via `cid_response/1`; sig/replay failures → 422 via `validation_failed_response/0`. `next/tests/http_publish.sh` (10 cases).
 - [x] **8d-accept** — `accept_format/1` + `accept_format_from/1` parse the Accept header into `:activity_json | :json | :sx | :cbor | :text`. Priority: activity+json > json > sx > cbor; everything else falls to text. `next/tests/http_accept.sh` (13 cases).
-- [ ] **8d-dispatch** — Wire format dispatch into responses (e.g., the `cid_response`/`actor_doc_response`/etc. emit body shapes matching the chosen format).
+- [x] **8d-dispatch-cap** — `capabilities_body_for/1` returns distinct stubs per format (json `{...}`, sx `(...)`, cbor `A1 64 caps 69 fed-sx-m1`); activity_json shares the json body. Route intercepts GET capabilities to thread the Accept format through `accept_format_from/1`. `next/tests/http_capabilities_format.sh` (13 cases).
+- [ ] **8d-dispatch-rest** — Same treatment for `actor_doc_response`, `artifact_response`, `projection_response`, `cid_response` (plus Content-Type headers).
 
 **Deliverables:**
 
@@ -997,6 +998,7 @@ A few things still under-specified; resolve as work begins.
 Newest first. One line per sub-deliverable commit. Erlang conformance gate
 (`bash lib/erlang/conformance.sh`) must remain 729/729 on every entry.
 
+- **2026-05-28** — Step 8d-dispatch-cap: `capabilities_body_for/1` returns distinct byte sequences per format — text reuses the existing `capabilities_body/0`; json/activity_json share `{"caps":"fed-sx-m1"}`; sx returns `(caps "fed-sx-m1")`; cbor returns a minimal `A1 64 caps 69 fed-sx-m1` map. Route now intercepts GET `/.well-known/sx-capabilities` to pull the Accept format via `accept_format_from/1` and dispatch through `capabilities_body_for`. Unknown formats fall back to text. POST capabilities still 404 (only GET handled). `next/tests/http_capabilities_format.sh` 13/13 verifies all formats + the intercept + no-Accept default. Content-Type headers not yet set (8d-dispatch-rest covers headers + applying the same shape to actor/artifact/projection/cid responses). Erlang conformance 729/729.
 - **2026-05-28** — Step 8d-accept: `accept_format/1` + `accept_format_from/1` parse the Accept header into a content-negotiation atom. Priority order via successive `match_prefix` checks: application/activity+json → `activity_json`; application/json → `json`; application/sx → `sx`; application/cbor → `cbor`; everything else (including nil / empty / non-binary) → `text`. Comma-separated lists with activity+json first still resolve to activity_json — leading-prefix match is sufficient for v1 envelopes. Step 8d split into 8d-accept (done) + 8d-dispatch (wire into response bodies). `next/tests/http_accept.sh` 13/13. Erlang conformance 729/729.
 - **2026-05-28** — Step 5c-populate: `bootstrap:populate_registry/0` walks `read_genesis` output and calls `registry:register/3` (gen_server API) for each entry. Total return is 31 = 3 + 10 + 7 + 3 + 3 + 2 + 3 across the seven kinds, matching the manifest authored in Step 4. `next/tests/bootstrap_populate.sh` 14/14 verifies per-kind counts + lookups against known names (`activity_types/create`, `object_types/define-activity`, `validators/envelope-shape`). Erlang conformance 729/729.
 - **2026-05-28** — Step 9-pre-fold: in-process integration test proving the full POST → publish → broadcast → projection-fold chain. With `projection:start_link` + `nx_kernel:start_link` + `nx_kernel:with_projections([p_count, p_collect])`, three authorized POST `/activity` calls advance both projections to 3 — and the kernel's log to 3 entries — and the projection's collected activity carries the POST body as `:object`. Unauthorized or sig-failed POSTs leave projection state unchanged. Step 9a/b proper (curl-driven smoke tests) wait on Step 8b-start (TCP) + Define\* SX-source eval bridge, but the structural chain is already verified end-to-end. `next/tests/http_publish_fold.sh` 10/10. Erlang conformance 729/729. Step 9 split into 9-pre-fold (done) + 9a + 9b.