fix(httpauth): wildcard resource fallback, json.Number precision, xerrors JSON error bodies (#1)

ClaimsPermissionProvider.ResolveMask now falls back to the "*" resource key when the
exact resource is absent in the JWT masks claim. Specific resource takes precedence;
wildcard is the fallback. Enables ADMIN wildcard masks ({"*": MaxInt64}) to pass every
endpoint guard without per-resource entries.

Add json.Number handling alongside existing int64/float64 paths. json.Number is
produced by jwt.WithJSONNumber() (httpauth-jwt) and preserves math.MaxInt64 exactly —
float64 would round to 2^63 and overflow on cast back to int64.

Export WriteJSONError(w, status, code, message) — shared JSON error helper for all
httpauth-* provider packages. Ensures a consistent {"code":"...","message":"..."} body
and Content-Type: application/json across the full middleware stack.

AuthzMiddleware and EnrichmentMiddleware now use WriteJSONError with xerrors code
constants (UNAUTHENTICATED, PERMISSION_DENIED, INTERNAL) instead of http.Error which
writes text/plain. AuthzMiddleware also fixes a wrong code string: UNAUTHORIZED →
UNAUTHENTICATED (stable gRPC-aligned name, matching xerrors.ErrUnauthorized).

Add xerrors v1.0.1 as a direct dependency for the code constants.

Reviewed-on: #1
Co-authored-by: Rene Nochebuena Guerrero <rene@nochebuena.dev>
Co-committed-by: Rene Nochebuena Guerrero <rene@nochebuena.dev>

CHANGELOG.md

@@ -5,6 +5,38 @@ All notable changes to this module will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this module adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [1.0.2] — 2026-05-18
+
+### Added
+
+- `ClaimsPermissionProvider.ResolveMask` now supports a wildcard resource key `"*"` as
+  a fallback when the requested resource is not present in the JWT masks claim. Specific
+  resource key takes precedence; wildcard is consulted only when the exact key is absent.
+  Primary use case: `ADMIN` role carries `{"*": MaxInt64}` — one JWT entry grants access
+  to every resource without per-resource enumeration.
+- `ClaimsPermissionProvider.ResolveMask` now handles `json.Number` mask values in
+  addition to the existing `int64` and `float64` paths. `json.Number` is produced by
+  `jwt.WithJSONNumber()` (used in `httpauth-jwt`); it preserves `math.MaxInt64` exactly
+  where float64 would overflow.
+- `WriteJSONError(w http.ResponseWriter, status int, code, message string)` — exported
+  helper that writes a structured JSON error body (`Content-Type: application/json`,
+  `{"code":"...","message":"..."}`). Intended for use by all `httpauth-*` provider
+  packages so the error format is enforced in one place.
+
+### Fixed
+
+- `AuthzMiddleware` and `EnrichmentMiddleware` now return JSON error bodies instead of
+  plain-text `http.Error` responses. Error codes are stable gRPC-aligned names from
+  `xerrors`: `UNAUTHENTICATED` (401), `PERMISSION_DENIED` (403), `INTERNAL` (500).
+  Previously `AuthzMiddleware` also used the wrong code `UNAUTHORIZED` for 401 responses
+  (correct value is `UNAUTHENTICATED`).
+
+### Dependencies
+
+- Added `code.nochebuena.dev/go/xerrors v1.0.1` (for code constants in error responses).
+
+[1.0.2]: https://code.nochebuena.dev/go/httpauth/releases/tag/v1.0.2
+
 ## [1.0.0] — 2026-05-08
 
 ### Added

authz.go

@@ -1,9 +1,11 @@
 package httpauth
 
 import (
+	"encoding/json"
 	"net/http"
 
 	"code.nochebuena.dev/go/rbac"
+	"code.nochebuena.dev/go/xerrors"
 )
 
 // AuthzMiddleware reads the rbac.Identity from context (set by EnrichmentMiddleware)
@@ -16,13 +18,13 @@ func AuthzMiddleware(provider rbac.PermissionProvider, resource string, required
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			identity, ok := rbac.FromContext(r.Context())
 			if !ok {
-				http.Error(w, "unauthorized", http.StatusUnauthorized)
+				WriteJSONError(w, http.StatusUnauthorized, string(xerrors.ErrUnauthorized), "unauthorized")
 				return
 			}
 
 			mask, err := provider.ResolveMask(r.Context(), identity.UID, resource)
 			if err != nil || !mask.Has(required) {
-				http.Error(w, "forbidden", http.StatusForbidden)
+				WriteJSONError(w, http.StatusForbidden, string(xerrors.ErrPermissionDenied), "forbidden")
 				return
 			}
 
@@ -30,3 +32,15 @@ func AuthzMiddleware(provider rbac.PermissionProvider, resource string, required
 		})
 	}
 }
+
+// WriteJSONError writes a structured JSON error body matching the httputil.Error format.
+// Used by all httpauth-* provider packages to ensure a consistent error format across
+// the full middleware stack.
+func WriteJSONError(w http.ResponseWriter, status int, code, message string) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	_ = json.NewEncoder(w).Encode(map[string]any{
+		"code":    code,
+		"message": message,
+	})
+}

claims_provider.go

@@ -2,6 +2,7 @@ package httpauth
 
 import (
 	"context"
+	"encoding/json"
 
 	"code.nochebuena.dev/go/rbac"
 )
@@ -25,15 +26,24 @@ func (p *claimsPermissionProvider) ResolveMask(ctx context.Context, _, resource
 	if !ok {
 		return 0, nil
 	}
-	permisos, ok := claims[p.claimsKey].(map[string]any)
+	masks, ok := claims[p.claimsKey].(map[string]any)
 	if !ok {
 		return 0, nil
 	}
-	switch v := permisos[resource].(type) {
-	case int64:
-		return rbac.PermissionMask(v), nil
-	case float64:
-		return rbac.PermissionMask(int64(v)), nil
+	// Check specific resource first, then wildcard fallback.
+	for _, key := range []string{resource, "*"} {
+		switch v := masks[key].(type) {
+		case int64:
+			return rbac.PermissionMask(v), nil
+		case float64:
+			return rbac.PermissionMask(int64(v)), nil
+		case json.Number:
+			n, err := v.Int64()
+			if err != nil {
+				return 0, nil
+			}
+			return rbac.PermissionMask(n), nil
+		}
 	}
 	return 0, nil
 }

enrichment.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 
 	"code.nochebuena.dev/go/rbac"
+	"code.nochebuena.dev/go/xerrors"
 )
 
 // IdentityEnricher builds an rbac.Identity from verified token data.
@@ -42,7 +43,7 @@ func EnrichmentMiddleware(enricher IdentityEnricher, opts ...EnrichOpt) func(htt
 		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 			uid, ok := getUID(r.Context())
 			if !ok {
-				http.Error(w, "unauthorized", http.StatusUnauthorized)
+				WriteJSONError(w, http.StatusUnauthorized, string(xerrors.ErrUnauthorized), "unauthorized")
 				return
 			}
 
@@ -50,7 +51,7 @@ func EnrichmentMiddleware(enricher IdentityEnricher, opts ...EnrichOpt) func(htt
 
 			identity, err := enricher.Enrich(r.Context(), uid, claims)
 			if err != nil {
-				http.Error(w, "internal server error", http.StatusInternalServerError)
+				WriteJSONError(w, http.StatusInternalServerError, string(xerrors.ErrInternal), "internal server error")
 				return
 			}
 

go.mod

@@ -2,4 +2,7 @@ module code.nochebuena.dev/go/httpauth
 
 go 1.26
 
-require code.nochebuena.dev/go/rbac v1.0.0
+require (
+	code.nochebuena.dev/go/rbac v1.0.0
+	code.nochebuena.dev/go/xerrors v1.0.1
+)

go.sum

@@ -1,2 +1,4 @@
 code.nochebuena.dev/go/rbac v1.0.0 h1:FnsU1HU6vvwchKuZNxDa9RPIFeNwJi0vShWvHKABMws=
 code.nochebuena.dev/go/rbac v1.0.0/go.mod h1:LzW8tTJmdbu6HHN26NZZ3HzzdlZAd1sp6aml25Cfz5c=
+code.nochebuena.dev/go/xerrors v1.0.1 h1:fgXoabY/ZwxAzaM1sKFf3sbL7ZHWyDxItB/rdbnl0mo=
+code.nochebuena.dev/go/xerrors v1.0.1/go.mod h1:03MMVfrhaf4XmTMgMrEUFCmuZPGHUCKDitiQvwCuwvY=

httpauth_test.go

@@ -2,7 +2,9 @@ package httpauth
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
+	"math"
 	"net/http"
 	"net/http/httptest"
 	"testing"
@@ -348,3 +350,111 @@ func TestChainPermissionProvider_ErrorPropagates(t *testing.T) {
 		t.Error("expected error from first provider, got nil")
 	}
 }
+
+// --- ClaimsPermissionProvider wildcard + json.Number ---
+
+func TestClaimsPermissionProvider_WildcardFallback(t *testing.T) {
+	p := NewClaimsPermissionProvider("permisos")
+	ctx := SetTokenData(context.Background(), "uid1", map[string]any{
+		"permisos": map[string]any{"*": int64(515)},
+	})
+	mask, err := p.ResolveMask(ctx, "uid1", "cualquier_recurso")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if mask != 515 {
+		t.Errorf("want 515 from wildcard, got %d", mask)
+	}
+}
+
+func TestClaimsPermissionProvider_SpecificBeatsWildcard(t *testing.T) {
+	p := NewClaimsPermissionProvider("permisos")
+	ctx := SetTokenData(context.Background(), "uid1", map[string]any{
+		"permisos": map[string]any{
+			"system": int64(42),
+			"*":      int64(999),
+		},
+	})
+	mask, err := p.ResolveMask(ctx, "uid1", "system")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if mask != 42 {
+		t.Errorf("want 42 from specific key, got %d (wildcard must not override specific)", mask)
+	}
+}
+
+func TestClaimsPermissionProvider_JSONNumber(t *testing.T) {
+	p := NewClaimsPermissionProvider("permisos")
+	ctx := SetTokenData(context.Background(), "uid1", map[string]any{
+		"permisos": map[string]any{"system": json.Number("9223372036854775807")},
+	})
+	mask, err := p.ResolveMask(ctx, "uid1", "system")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if int64(mask) != math.MaxInt64 {
+		t.Errorf("want MaxInt64 (%d), got %d", int64(math.MaxInt64), int64(mask))
+	}
+}
+
+// --- JSON error body assertions ---
+
+func assertJSONError(t *testing.T, rec *httptest.ResponseRecorder, wantStatus int, wantCode string) {
+	t.Helper()
+	if rec.Code != wantStatus {
+		t.Errorf("want status %d, got %d", wantStatus, rec.Code)
+	}
+	if ct := rec.Header().Get("Content-Type"); ct != "application/json" {
+		t.Errorf("want Content-Type application/json, got %q", ct)
+	}
+	var body map[string]any
+	if err := json.NewDecoder(rec.Body).Decode(&body); err != nil {
+		t.Fatalf("response body is not valid JSON: %v", err)
+	}
+	if body["code"] != wantCode {
+		t.Errorf("want code %q, got %q", wantCode, body["code"])
+	}
+}
+
+func TestAuthzMiddleware_ForbiddenJSON(t *testing.T) {
+	mp := &mockProvider{mask: rbac.PermissionMask(0)}
+	h := AuthzMiddleware(mp, "resource", testPerm)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	req := httptest.NewRequest(http.MethodGet, "/", nil)
+	ctx := rbac.SetInContext(req.Context(), rbac.NewIdentity("uid1", "", ""))
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, req.WithContext(ctx))
+	assertJSONError(t, rec, http.StatusForbidden, "PERMISSION_DENIED")
+}
+
+func TestAuthzMiddleware_UnauthorizedJSON(t *testing.T) {
+	mp := &mockProvider{}
+	h := AuthzMiddleware(mp, "resource", testPerm)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/", nil))
+	assertJSONError(t, rec, http.StatusUnauthorized, "UNAUTHENTICATED")
+}
+
+func TestEnrichmentMiddleware_NoUIDJSON(t *testing.T) {
+	h := EnrichmentMiddleware(&mockEnricher{})(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/", nil))
+	assertJSONError(t, rec, http.StatusUnauthorized, "UNAUTHENTICATED")
+}
+
+func TestEnrichmentMiddleware_EnricherErrorJSON(t *testing.T) {
+	me := &mockEnricher{err: errors.New("db error")}
+	inner := EnrichmentMiddleware(me)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+	}))
+	h := injectTokenData("uid1", nil, inner)
+	rec := httptest.NewRecorder()
+	h.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/", nil))
+	assertJSONError(t, rec, http.StatusInternalServerError, "INTERNAL")
+}