feat(pg-delta): add --filter to catalog-export

.changeset/catalog-export-filter.md

@@ -0,0 +1,5 @@
+---
+"@supabase/pg-delta": minor
+---
+
+Add `--filter` option to the `catalog-export` CLI command to scope the exported catalog to matching schemas/objects.

packages/pg-delta/src/cli/commands/catalog-export.ts

@@ -4,11 +4,13 @@
 
 import { writeFile } from "node:fs/promises";
 import { buildCommand, type CommandContext } from "@stricli/core";
+import { filterCatalog } from "../../core/catalog.filter.ts";
 import { extractCatalog } from "../../core/catalog.model.ts";
 import {
   serializeCatalog,
   stringifyCatalogSnapshot,
 } from "../../core/catalog.snapshot.ts";
+import type { FilterDSL } from "../../core/integrations/filter/dsl.ts";
 import { createManagedPool } from "../../core/postgres-config.ts";
 
 export const catalogExportCommand = buildCommand({
@@ -30,6 +32,21 @@ export const catalogExportCommand = buildCommand({
         parse: String,
         optional: true,
       },
+      filter: {
+        kind: "parsed",
+        brief:
+          'Filter DSL as inline JSON to filter changes (e.g., \'{"schema":"public"}\').',
+        parse: (value: string): FilterDSL => {
+          try {
+            return JSON.parse(value) as FilterDSL;
+          } catch (error) {
+            throw new Error(
+              `Invalid filter JSON: ${error instanceof Error ? error.message : String(error)}`,
+            );
+          }
+        },
+        optional: true,
+      },
     },
     aliases: {
       t: "target",
@@ -48,6 +65,10 @@ Use cases:
   - Snapshot template1 for use as an empty-database baseline
   - Snapshot a production database to generate revert migrations
   - Snapshot any state for reproducible offline diffs
+
+Pass --filter to scope the snapshot to a subset of the catalog (same
+Filter DSL accepted by plan/sync). Useful when committing a baseline
+snapshot to a repo and only one schema's drift is interesting.
     `.trim(),
   },
   async func(
@@ -56,6 +77,7 @@ Use cases:
       target: string;
       output: string;
       role?: string;
+      filter?: FilterDSL;
     },
   ) {
     const { pool, close } = await createManagedPool(flags.target, {
@@ -65,7 +87,10 @@ Use cases:
 
     try {
       const catalog = await extractCatalog(pool);
-      const snapshot = serializeCatalog(catalog);
+      const scoped = flags.filter
+        ? await filterCatalog(catalog, flags.filter)
+        : catalog;
+      const snapshot = serializeCatalog(scoped);
       const json = stringifyCatalogSnapshot(snapshot);
       await writeFile(flags.output, json, "utf-8");
       this.process.stdout.write(

packages/pg-delta/src/core/catalog.filter.ts

@@ -0,0 +1,84 @@
+/**
+ * Prune a catalog to the objects that match a Filter DSL expression.
+ *
+ * The Filter DSL is defined over Change objects, so the catalog is
+ * diffed against an empty baseline first to materialize one CREATE
+ * change per object. The filter then evaluates against the same shape
+ * it would at plan time, and the surviving stableIds drive the prune.
+ *
+ * Dependency cascade is not applied. A scoped snapshot is partial by
+ * design: out-of-scope owners, roles, and types must exist on the
+ * target DB at apply time. Cascading would expand the filter beyond
+ * what the caller asked for and, in practice, collapse schema-scoped
+ * exports whose kept objects reference cluster-scoped owners.
+ */
+
+import { diffCatalogs } from "./catalog.diff.ts";
+import { Catalog, createEmptyCatalog } from "./catalog.model.ts";
+import { compileFilterDSL, type FilterDSL } from "./integrations/filter/dsl.ts";
+
+export async function filterCatalog(
+  catalog: Catalog,
+  filter: FilterDSL,
+): Promise<Catalog> {
+  const empty = await createEmptyCatalog(catalog.version, catalog.currentUser);
+  const changes = diffCatalogs(empty, catalog);
+  const filterFn = compileFilterDSL(filter);
+
+  const keep = new Set<string>();
+  for (const change of changes) {
+    if (!filterFn(change)) continue;
+    for (const id of change.creates ?? []) keep.add(id);
+  }
+
+  return pruneCatalog(catalog, keep);
+}
+
+function filterRecord<T>(
+  record: Record<string, T>,
+  keep: ReadonlySet<string>,
+): Record<string, T> {
+  return Object.fromEntries(
+    Object.entries(record).filter(([id]) => keep.has(id)),
+  );
+}
+
+function pruneCatalog(catalog: Catalog, keep: ReadonlySet<string>): Catalog {
+  const tables = filterRecord(catalog.tables, keep);
+  const materializedViews = filterRecord(catalog.materializedViews, keep);
+
+  return new Catalog({
+    aggregates: filterRecord(catalog.aggregates, keep),
+    collations: filterRecord(catalog.collations, keep),
+    compositeTypes: filterRecord(catalog.compositeTypes, keep),
+    domains: filterRecord(catalog.domains, keep),
+    enums: filterRecord(catalog.enums, keep),
+    extensions: filterRecord(catalog.extensions, keep),
+    procedures: filterRecord(catalog.procedures, keep),
+    indexes: filterRecord(catalog.indexes, keep),
+    materializedViews,
+    subscriptions: filterRecord(catalog.subscriptions, keep),
+    publications: filterRecord(catalog.publications, keep),
+    rlsPolicies: filterRecord(catalog.rlsPolicies, keep),
+    roles: filterRecord(catalog.roles, keep),
+    schemas: filterRecord(catalog.schemas, keep),
+    sequences: filterRecord(catalog.sequences, keep),
+    tables,
+    triggers: filterRecord(catalog.triggers, keep),
+    eventTriggers: filterRecord(catalog.eventTriggers, keep),
+    rules: filterRecord(catalog.rules, keep),
+    ranges: filterRecord(catalog.ranges, keep),
+    views: filterRecord(catalog.views, keep),
+    foreignDataWrappers: filterRecord(catalog.foreignDataWrappers, keep),
+    servers: filterRecord(catalog.servers, keep),
+    userMappings: filterRecord(catalog.userMappings, keep),
+    foreignTables: filterRecord(catalog.foreignTables, keep),
+    depends: catalog.depends.filter(
+      (d) =>
+        keep.has(d.dependent_stable_id) && keep.has(d.referenced_stable_id),
+    ),
+    indexableObjects: { ...tables, ...materializedViews },
+    version: catalog.version,
+    currentUser: catalog.currentUser,
+  });
+}

packages/pg-delta/src/core/catalog.model.ts

@@ -182,8 +182,10 @@ let _pg1516Baseline: Catalog | null = null;
 let _pg17Baseline: Catalog | null = null;
 
 async function loadBaselineJson(): Promise<Record<string, unknown>> {
-  const mod =
-    await import("./fixtures/empty-catalogs/postgres-15-16-baseline.json");
+  const mod = await import(
+    "./fixtures/empty-catalogs/postgres-15-16-baseline.json",
+    { with: { type: "json" } }
+  );
   return mod.default as Record<string, unknown>;
 }
 

packages/pg-delta/tests/integration/catalog-export-filter.test.ts

@@ -0,0 +1,153 @@
+import { describe, expect, test } from "bun:test";
+import { extractCatalog } from "../../src/core/catalog.model.ts";
+import { filterCatalog } from "../../src/core/catalog.filter.ts";
+import {
+  deserializeCatalog,
+  serializeCatalog,
+  stringifyCatalogSnapshot,
+} from "../../src/core/catalog.snapshot.ts";
+import { createPlan } from "../../src/core/plan/create.ts";
+import { POSTGRES_VERSIONS } from "../constants.ts";
+import { withDb } from "../utils.ts";
+
+for (const pgVersion of POSTGRES_VERSIONS) {
+  describe(`catalog-export --filter (pg${pgVersion})`, () => {
+    test(
+      "filterCatalog keeps only objects matching the filter",
+      withDb(pgVersion, async (db) => {
+        await db.branch.query(`
+          CREATE SCHEMA app;
+          CREATE TABLE app.users (id serial PRIMARY KEY, name text NOT NULL);
+          CREATE TABLE app.posts (id serial PRIMARY KEY, title text NOT NULL);
+          CREATE SCHEMA other;
+          CREATE TABLE other.config (key text PRIMARY KEY);
+        `);
+
+        const full = await extractCatalog(db.branch);
+        const scoped = await filterCatalog(full, { "*/schema": "app" });
+
+        expect(Object.keys(scoped.schemas).sort()).toEqual(["schema:app"]);
+        expect(Object.keys(scoped.tables).sort()).toEqual([
+          "table:app.posts",
+          "table:app.users",
+        ]);
+        expect(Object.keys(scoped.tables)).not.toContain("table:other.config");
+        expect(Object.keys(scoped.schemas)).not.toContain("schema:other");
+        expect(Object.keys(scoped.schemas)).not.toContain("schema:public");
+      }),
+    );
+
+    test(
+      "filterCatalog drops pg_depend edges that touch pruned objects",
+      withDb(pgVersion, async (db) => {
+        await db.branch.query(`
+          CREATE SCHEMA app;
+          CREATE TABLE app.users (id serial PRIMARY KEY);
+          CREATE SCHEMA other;
+          CREATE TABLE other.t (id serial PRIMARY KEY);
+        `);
+
+        const full = await extractCatalog(db.branch);
+        const scoped = await filterCatalog(full, { "*/schema": "app" });
+
+        for (const dep of scoped.depends) {
+          expect(dep.dependent_stable_id).not.toContain("other");
+          expect(dep.referenced_stable_id).not.toContain("other");
+        }
+      }),
+    );
+
+    test(
+      "round-trip: filtered snapshot diffs to zero against live source with same filter",
+      withDb(pgVersion, async (db) => {
+        await db.branch.query(`
+          CREATE SCHEMA app;
+          CREATE TABLE app.users (id serial PRIMARY KEY, name text NOT NULL);
+          CREATE SCHEMA other;
+          CREATE TABLE other.config (key text PRIMARY KEY);
+        `);
+
+        const full = await extractCatalog(db.branch);
+        const filter = { "*/schema": "app" };
+        const scoped = await filterCatalog(full, filter);
+
+        // Reconstruct via the snapshot serializer to prove the prune survives
+        // a real save→load cycle (which is what catalog-export does).
+        const roundTripped = deserializeCatalog(
+          JSON.parse(stringifyCatalogSnapshot(serializeCatalog(scoped))),
+        );
+
+        const plan = await createPlan(db.branch, roundTripped, { filter });
+        expect(plan).toBeNull();
+      }),
+    );
+
+    test(
+      "schema filter keeps schema even when its owner role is filtered out",
+      withDb(pgVersion, async (db) => {
+        // Reproduces a class of bug surfaced by Supabase images: the kept
+        // schema's CREATE change `requires` an owner role; if filterCatalog
+        // ran cascadeExclusions, the filter would drop the role change,
+        // cascade would propagate to the schema, and the snapshot would
+        // come out empty. The filter must keep the schema (and its objects)
+        // even when out-of-scope owners exist in the live catalog.
+        await db.branch.query(`
+          CREATE ROLE app_owner;
+          CREATE SCHEMA realtime AUTHORIZATION app_owner;
+          CREATE TABLE realtime.subscription (id serial PRIMARY KEY);
+        `);
+
+        const full = await extractCatalog(db.branch);
+        const scoped = await filterCatalog(full, { "*/schema": "realtime" });
+
+        expect(Object.keys(scoped.schemas)).toContain("schema:realtime");
+        expect(Object.keys(scoped.tables)).toContain(
+          "table:realtime.subscription",
+        );
+        // The owner role itself is filtered out (no `role/schema` to match).
+        expect(Object.keys(scoped.roles)).not.toContain("role:app_owner");
+      }),
+    );
+
+    test(
+      "round-trip matches realtime usage: schema filter survives plan",
+      withDb(pgVersion, async (db) => {
+        // Mirrors the Realtime baseline workflow: snapshot a 'kitchen sink'
+        // database scoped to one schema, then drift-check tenant against it
+        // using the same filter at plan time.
+        await db.branch.query(`
+          CREATE SCHEMA realtime;
+          CREATE TABLE realtime.schema_migrations (
+            version bigint PRIMARY KEY,
+            inserted_at timestamp
+          );
+          CREATE TABLE realtime.subscription (
+            id bigserial PRIMARY KEY,
+            entity regclass NOT NULL,
+            filters jsonb DEFAULT '[]'::jsonb
+          );
+          CREATE SCHEMA auth;
+          CREATE TABLE auth.users (id uuid PRIMARY KEY);
+          CREATE TABLE auth.sessions (id uuid PRIMARY KEY);
+        `);
+
+        const full = await extractCatalog(db.branch);
+        const filter = { "*/schema": "realtime" };
+        const scoped = await filterCatalog(full, filter);
+
+        expect(Object.keys(scoped.schemas)).toContain("schema:realtime");
+        expect(Object.keys(scoped.schemas)).not.toContain("schema:auth");
+        expect(Object.keys(scoped.tables)).toContain(
+          "table:realtime.schema_migrations",
+        );
+        expect(Object.keys(scoped.tables)).not.toContain("table:auth.users");
+
+        const snapshot = deserializeCatalog(
+          JSON.parse(stringifyCatalogSnapshot(serializeCatalog(scoped))),
+        );
+        const plan = await createPlan(db.branch, snapshot, { filter });
+        expect(plan).toBeNull();
+      }),
+    );
+  });
+}