@@ -0,0 +1,14 @@
+---
+"@objectstack/metadata-protocol": patch
+---
+
+The metadata door serves a code-defined datasource's code definition while a stored row under its name still exists
+
+Clause-②: no
+
+- `GET /api/v1/meta/datasource/:name`, the `GET /api/v1/meta/datasource` list and the `effective` layer of `GET /api/v1/meta/datasource/:name/layers` now skip a stored `sys_metadata` row under a datasource name the host registers from code: one an installed package declares in `*.datasource.ts`, or the host's `default`. They serve the in-memory code definition instead. The datasource admin door and the boot restore already serve that ("code wins on collision"). Before this change the stored row was served first, so the two doors answered with two different bodies for one name.
+- The decision is made by name, through the same predicate the reads already ask for a shipped flow name. It never reads a row's `origin`. Every other type keeps ADR-0005's read order, in which the stored overlay wins.
+- Unchanged: the row stays at rest and is still reported in the layered read's `overlay`. The read envelope stays `deletable: true` while the row exists, and `DELETE /api/v1/meta/datasource/:name` still removes it as the repair. A draft read (`state: 'draft'`, or the draft preview) is still answered from the draft row. A runtime datasource's stored row is served as before.
+- The `/meta` and admin doors already refuse to write such a row. This change affects only how a row left from before that refusal is read.
+- Not moved: `GET /api/v1/meta/datasource/:name/published` still serves the stored row, which is the active overlay row that route describes.
+- ⛔ No public export, signature, schema or accept-set change. The built entry declarations gain two `private` member names on `ObjectStackProtocolImplementation`.
@@ -111,10 +111,19 @@ function makeSession(opts: {
     seed?: Row[];
     /** [#21944] The kernel services the protocol resolves — the host's code-datasource set among them. */
     services?: Map<string, unknown>;
+    /**
+     * [#21922] A registry that keeps what is registered under the bare key and
+     * lists it, as the real one does, so a stored row the hydrator registers
+     * (the boot pull, an unscoped list) is read back. Off: the registry lists
+     * nothing, as the other cases assume.
+     */
+    hydrating?: boolean;
 } = {}) {
     const rows = new Map<string, Row>();
     for (const r of opts.seed ?? []) rows.set(r.id, r);
     const historyRows: Array<Record<string, unknown>> = [];
+    /** [#21922] The bare-key entries a hydrating registry holds, per type. */
+    const registered = new Map<string, Map<string, Record<string, unknown>>>();
 
     const engine: any = {
         async findOne(table: string, o: { where: Record<string, unknown> }) {
@@ -126,10 +135,15 @@ function makeSession(opts: {
             for (const row of rows.values()) if (matchesWhere(row as any, o.where)) return row;
             return null;
         },
-        async find(table: string) {
+        async find(table: string, o?: { where?: Record<string, unknown>; limit?: number }) {
             if (table === 'sys_metadata_history') return historyRows;
             if (table !== 'sys_metadata') return [];
-            return Array.from(rows.values());
+            // [#21922] The caller's predicate, as the real engine applies it:
+            // the list reads one type's ACTIVE rows, so a draft row of the
+            // same name must not reach it. `check:objectql-double-limit` —
+            // the caller's bound, applied after the filter.
+            const matched = Array.from(rows.values()).filter((row) => matchesWhere(row as any, o?.where ?? {}));
+            return o?.limit === undefined ? matched : matched.slice(0, o.limit);
         },
         async insert(table: string, data: Record<string, unknown>) {
             if (table === 'sys_metadata_history') {
@@ -158,15 +172,21 @@ function makeSession(opts: {
             return { deleted: existed ? 1 : 0 };
         },
         registry: {
-            registerItem: () => {},
+            registerItem: (type: string, item: Record<string, unknown>, keyField = 'name') => {
+                if (!opts.hydrating) return;
+                if (!registered.has(type)) registered.set(type, new Map());
+                registered.get(type)!.set(String(item[keyField]), item);
+            },
             registerObject: () => {},
-            listItems: () => [],
-            // The served code definition, as the runtime's in-memory
-            // registration serves it on a read.
-            getItem: (type: string, name: string) =>
-                (type === 'datasource' && name === CODE_DS && (opts.packages ?? []).length > 0
+            listItems: (type: string) => [...(registered.get(type)?.values() ?? [])],
+            // The real registry answers the bare slot first; with nothing
+            // registered there, the served code definition, as the runtime's
+            // in-memory registration serves it on a read.
+            getItem: (type: string, name: string) => registered.get(type)?.get(name)
+                ?? (type === 'datasource' && name === CODE_DS && (opts.packages ?? []).length > 0
                     ? { ...body(CODE_DS, 'External Analytics (SQLite)'), origin: 'code' }
                     : undefined),
+            isPackageDisabled: () => false,
             applyNavContributions: (app: unknown) => app,
             // A code-defined datasource is never a SchemaRegistry item — the
             // artifact-only lookup misses it, exactly as on a booted showcase.
@@ -530,3 +550,180 @@ for (const { label, environmentId } of KERNELS) {
         });
     });
 }
+
+/**
+ * [#21922] The active reads DECLINE a stored row under a code-defined
+ * datasource name (triage's answer A, the #20946 shape).
+ *
+ * A row the `/meta` door saved before it refused these names, or one an earlier
+ * runtime write left, sits under a name the host registers from code. The boot
+ * restore no longer registers it over the code definition, so the
+ * MetadataService holds the code definition. But the by-name read still served
+ * the row first (ADR-0005's read order, `findServedOverlayRow`), and the list
+ * did too, because its stored rows are the higher layer over the
+ * MetadataService's. Now the one predicate the reads already asked of a shipped
+ * flow name (`declinesStoredRow`) answers for these names too:
+ *
+ *  - (a) the by-name read, the list and the layered read's `effective` serve
+ *    the code definition while the row exists — the list also after the row
+ *    was hydrated into the registry's bare slot (the registry half);
+ *  - (b) the row stays FOUND, so `deletable` still offers the repair, and the
+ *    `/meta` DELETE still removes it;
+ *  - (c) a runtime datasource's stored row is served exactly as before;
+ *  - (d) a draft is answered as a draft.
+ *
+ * The MetadataService double is the composition's: the in-memory registrations
+ * the runtime made at boot, read first (`MetadataManager.get` / `list`).
+ */
+const CODE_LABEL = 'External Analytics (SQLite)';
+const DEFAULT_LABEL = 'Host Default 21922';
+const SHADOW_LABEL = 'Shadow 21922';
+const RUNTIME_ROW_LABEL = 'Runtime 21922 (stored row)';
+const DRAFT_LABEL = 'Draft 21922';
+
+/** A row an earlier runtime write left under `name`: it asserts `origin: 'runtime'` and its own file. */
+const residueRow = (name: string, overrides: { label?: string; state?: string } = {}): Row => ({
+    id: `row_residue_${name}_${overrides.state ?? 'active'}`,
+    type: 'datasource',
+    name,
+    organization_id: null,
+    package_id: null,
+    state: overrides.state ?? 'active',
+    metadata: JSON.stringify({
+        ...body(name, overrides.label ?? SHADOW_LABEL),
+        origin: 'runtime',
+        config: { filename: `shadow-${name}.db` },
+    }),
+    checksum: `sha256_residue_${name}`,
+});
+
+/** The `metadata` service: what the runtime registered in memory, read first. */
+const metadataServiceOf = (items: Array<Record<string, unknown>>) => {
+    const byName = new Map(items.map((it) => [String(it.name), it] as const));
+    const read = (type: string, name: string) => (type === 'datasource' ? byName.get(name) : undefined);
+    return {
+        get: async (type: string, name: string) => read(type, name),
+        getDiagnosed: async (type: string, name: string) => ({ data: read(type, name), degraded: false, errors: [] as string[] }),
+        list: async (type: string) => (type === 'datasource' ? [...byName.values()] : []),
+    };
+};
+
+/**
+ * The two code definitions (`AppPlugin`, `DefaultDatasourcePlugin`), and the
+ * runtime datasource as the restore registered it, under a label its row does
+ * not carry, so the control can tell which layer answered.
+ */
+const IN_MEMORY: Array<Record<string, unknown>> = [
+    { ...body(CODE_DS, CODE_LABEL), origin: 'code', _packageId: PACKAGE_ID },
+    { name: 'default', label: DEFAULT_LABEL, driver: 'sqlite', config: { filename: 'host.db' }, origin: 'code' },
+    { ...body(RUNTIME_DS, 'Runtime 21922 (MetadataService copy)'), origin: 'runtime' },
+];
+
+for (const { label, environmentId } of KERNELS) {
+    describe(`[#21922] the active reads decline a stored row under a code-defined datasource name — ${label}`, () => {
+        beforeEach(resetEnvHatch);
+        afterEach(resetEnvHatch);
+
+        const session = (seed: Row[]) => makeSession({
+            ...(environmentId ? { environmentId } : {}),
+            packages: [SHOWCASE_PACKAGE],
+            services: new Map<string, unknown>([
+                [CODE_NAMES_SERVICE, new Set([CODE_DS, 'default'])],
+                ['metadata', metadataServiceOf(IN_MEMORY)],
+            ]),
+            seed,
+            hydrating: true,
+        });
+        const byName = (protocol: any, request: Record<string, unknown>) =>
+            protocol.getMetaItem({ type: 'datasource', ...request });
+        const listed = async (protocol: any, name: string): Promise<Array<Record<string, any>>> =>
+            ((await protocol.getMetaItems({ type: 'datasource' })).items as Array<Record<string, any>>)
+                .filter((it) => it.name === name);
+        /** The boot pull's call (`loadMetaFromDb`): the row, hydrated under the registry's bare key. */
+        const hydrate = (protocol: any, row: Row) => {
+            protocol.hydrateOverlayIntoRegistry('datasource', JSON.parse(row.metadata), { organizationId: null });
+            expect(protocol.engine.registry.getItem('datasource', row.name)?.label).toBe(SHADOW_LABEL);
+        };
+
+        it('(a) by name: the code definition is served while the row exists, and the envelope still offers the repair', async () => {
+            const { protocol, rows } = session([residueRow(CODE_DS)]);
+
+            for (const type of ['datasource', 'datasources']) {
+                const read = await byName(protocol, { type, name: CODE_DS });
+                expect(read.item, type).toMatchObject({ origin: 'code', label: CODE_LABEL, _packageId: PACKAGE_ID });
+                expect(read.item.config, type).toEqual({ filename: `${CODE_DS}.db` });
+                expect({ editable: read.editable, deletable: read.deletable }, type).toEqual({ editable: false, deletable: true });
+            }
+            expect(rows.size).toBe(1);
+        });
+
+        it('(a) in the list: one entry under the name, the code definition, before and after the row is hydrated into the registry', async () => {
+            const row = residueRow(CODE_DS);
+            const { protocol } = session([row]);
+
+            const before = await listed(protocol, CODE_DS);
+            hydrate(protocol, row);
+            const after = await listed(protocol, CODE_DS);
+
+            for (const list of [before, after]) {
+                expect(list.map((it) => it.label)).toEqual([CODE_LABEL]);
+                expect(list[0]).toMatchObject({ origin: 'code', _packageId: PACKAGE_ID });
+            }
+            // The by-name read agrees with the list after the hydration too.
+            expect((await byName(protocol, { name: CODE_DS })).item.label).toBe(CODE_LABEL);
+        });
+
+        it('(a) the host\'s `default`, which no package declares, the same way', async () => {
+            const row = residueRow('default');
+            const { protocol } = session([row]);
+
+            expect((await byName(protocol, { name: 'default' })).item).toMatchObject({ origin: 'code', label: DEFAULT_LABEL });
+            hydrate(protocol, row);
+            expect((await listed(protocol, 'default')).map((it) => it.label)).toEqual([DEFAULT_LABEL]);
+        });
+
+        it('(a) the layered read: `effective` is the code definition, and the row is still reported in `overlay`', async () => {
+            const { protocol } = session([residueRow(CODE_DS)]);
+
+            const layered = await protocol.getMetaItemLayered({ type: 'datasource', name: CODE_DS });
+
+            expect(layered.effective).toMatchObject({ origin: 'code', label: CODE_LABEL });
+            expect(layered.code).toMatchObject({ origin: 'code', label: CODE_LABEL });
+            expect(layered.overlay).toMatchObject({ origin: 'runtime', label: SHADOW_LABEL });
+            expect(layered.overlayScope).toBe('env');
+            expect({ editable: layered.editable, deletable: layered.deletable }).toEqual({ editable: false, deletable: true });
+        });
+
+        it('(b) the /meta DELETE still removes the row (the repair), and the reads serve the code definition after it', async () => {
+            const { protocol, rows } = session([residueRow(CODE_DS)]);
+
+            const res = await protocol.deleteMetaItem({ type: 'datasource', name: CODE_DS });
+
+            expect(res).toMatchObject({ success: true, reset: true });
+            expect(rows.size).toBe(0);
+            const read = await byName(protocol, { name: CODE_DS });
+            expect(read.item).toMatchObject({ origin: 'code', label: CODE_LABEL });
+            expect(read.deletable).toBe(false);
+            expect((await listed(protocol, CODE_DS)).map((it) => it.label)).toEqual([CODE_LABEL]);
+        });
+
+        it('(c) control: a runtime datasource\'s stored row is still served, by name and in the list', async () => {
+            const row = residueRow(RUNTIME_DS, { label: RUNTIME_ROW_LABEL });
+            const { protocol } = session([row]);
+
+            expect((await byName(protocol, { name: RUNTIME_DS })).item).toMatchObject({ label: RUNTIME_ROW_LABEL });
+            expect((await listed(protocol, RUNTIME_DS)).map((it) => it.label)).toEqual([RUNTIME_ROW_LABEL]);
+            const layered = await protocol.getMetaItemLayered({ type: 'datasource', name: RUNTIME_DS });
+            expect(layered.effective).toMatchObject({ label: RUNTIME_ROW_LABEL });
+        });
+
+        it('(d) a draft is answered as a draft: the strict draft read and the preview arm serve the draft row', async () => {
+            const { protocol } = session([residueRow(CODE_DS), residueRow(CODE_DS, { state: 'draft', label: DRAFT_LABEL })]);
+
+            expect((await byName(protocol, { name: CODE_DS, state: 'draft' })).item).toMatchObject({ label: DRAFT_LABEL });
+            expect((await byName(protocol, { name: CODE_DS, previewDrafts: true })).item).toMatchObject({ label: DRAFT_LABEL, _draft: true });
+            // The active read beside them still serves the code definition.
+            expect((await byName(protocol, { name: CODE_DS })).item).toMatchObject({ label: CODE_LABEL });
+        });
+    });
+}