feat: accept Expression for v2 RTDB instance option

spec/v2/providers/database.spec.ts

@@ -21,11 +21,15 @@
 // SOFTWARE.
 
 import { expect } from "chai";
+import * as sinon from "sinon";
 import { PathPattern } from "../../../src/common/utilities/path-pattern";
 import * as database from "../../../src/v2/providers/database";
 import { expectType } from "../../common/metaprogramming";
 import { MINIMAL_V2_ENDPOINT } from "../../fixtures";
 import { CloudEvent, onInit } from "../../../src/v2/core";
+import * as params from "../../../src/params";
+import * as logger from "../../../src/logger";
+import { stackToWire } from "../../../src/runtime/manifest";
 
 const RAW_RTDB_EVENT: database.RawRTDBCloudEvent = {
   data: {
@@ -46,7 +50,17 @@ const RAW_RTDB_EVENT: database.RawRTDBCloudEvent = {
   authtype: "unauthenticated",
 };
 
+const TEST_RTDB_INSTANCE_ENV_VAR = "TEST_RTDB_INSTANCE_FOR_GETOPTS";
+const RESOLVED_RTDB_INSTANCE = "resolved-instance";
+
 describe("database", () => {
+  afterEach(() => {
+    params.clearParams();
+    sinon.restore();
+    delete process.env.FUNCTIONS_CONTROL_API;
+    delete process.env[TEST_RTDB_INSTANCE_ENV_VAR];
+  });
+
   describe("makeParams", () => {
     it("should make params with basic path", () => {
       const event: database.RawRTDBCloudEvent = {
@@ -146,6 +160,15 @@ describe("database", () => {
         },
       });
     });
+
+    it("should preserve instance Expression", () => {
+      const p = params.defineString(TEST_RTDB_INSTANCE_ENV_VAR);
+
+      expect(database.getOpts({ ref: "/foo", instance: p })).to.deep.include({
+        path: "foo",
+        instance: p,
+      });
+    });
   });
 
   describe("makeEndpoint", () => {
@@ -209,6 +232,37 @@ describe("database", () => {
         },
       });
     });
+
+    it("should create an endpoint with an instance Expression as a path pattern", () => {
+      const instance = params.defineString(TEST_RTDB_INSTANCE_ENV_VAR);
+      const ep = database.makeEndpoint(
+        database.writtenEventType,
+        {
+          region: "us-central1",
+          labels: { 1: "2" },
+        },
+        new PathPattern("foo/bar"),
+        instance
+      );
+
+      expect(ep).to.deep.equal({
+        ...MINIMAL_V2_ENDPOINT,
+        platform: "gcfv2",
+        labels: {
+          1: "2",
+        },
+        region: ["us-central1"],
+        eventTrigger: {
+          eventType: database.writtenEventType,
+          eventFilters: {},
+          eventFilterPathPatterns: {
+            ref: "foo/bar",
+            instance,
+          },
+          retry: false,
+        },
+      });
+    });
   });
 
   describe("onChangedOperation", () => {
@@ -543,6 +597,66 @@ describe("database", () => {
         },
       });
     });
+
+    it("should create a function with instance Expression without deployment warning", () => {
+      process.env.FUNCTIONS_CONTROL_API = "true";
+      const warnSpy = sinon.spy(logger, "warn");
+      const instance = params.defineString(TEST_RTDB_INSTANCE_ENV_VAR);
+
+      const func = database.onValueCreated(
+        {
+          ref: "/foo/{bar}/",
+          instance,
+        },
+        () => 2
+      );
+
+      expect(warnSpy.callCount).to.equal(0);
+      expect(func.__endpoint.eventTrigger.eventFilters).to.deep.equal({});
+      expect(func.__endpoint.eventTrigger.eventFilterPathPatterns).to.deep.equal({
+        ref: "foo/{bar}",
+        instance,
+      });
+
+      const wire = stackToWire({
+        specVersion: "v1alpha1",
+        requiredAPIs: [],
+        endpoints: {
+          exprInstance: func.__endpoint,
+        },
+      }) as any;
+
+      expect(wire.endpoints.exprInstance.eventTrigger.eventFilterPathPatterns.instance).to.equal(
+        `{{ params.${TEST_RTDB_INSTANCE_ENV_VAR} }}`
+      );
+      expect(warnSpy.callCount).to.equal(0);
+    });
+
+    it("should resolve instance Expression at runtime", async () => {
+      process.env[TEST_RTDB_INSTANCE_ENV_VAR] = RESOLVED_RTDB_INSTANCE;
+      const instance = params.defineString(TEST_RTDB_INSTANCE_ENV_VAR);
+      const valueSpy = sinon.spy(instance, "value");
+      let capturedEvent: database.DatabaseEvent<any, { bar: string }>;
+
+      const func = database.onValueCreated(
+        {
+          ref: "/foo/{bar}/",
+          instance,
+        },
+        (event) => {
+          capturedEvent = event;
+        }
+      );
+
+      await func({
+        ...RAW_RTDB_EVENT,
+        instance: RESOLVED_RTDB_INSTANCE,
+        ref: "foo/bar-value",
+      } as any);
+
+      expect(valueSpy.callCount).to.equal(1);
+      expect(capturedEvent.params).to.deep.equal({ bar: "bar-value" });
+    });
   });
 
   describe("onValueUpdated", () => {

src/v2/providers/database.ts

@@ -117,7 +117,7 @@ export interface ReferenceOptions<Ref extends string = string> extends options.E
    * Examples: 'my-instance-1', 'my-instance-*'
    * Note: The capture syntax cannot be used for 'instance'.
    */
-  instance?: string;
+  instance?: string | Expression<string>;
 
   /**
    * If true, do not deploy or emulate this function.
@@ -480,7 +480,7 @@ export function onValueDeleted<Ref extends string>(
 /** @internal */
 export function getOpts(referenceOrOpts: string | ReferenceOptions) {
   let path: string;
-  let instance: string;
+  let instance: string | Expression<string>;
   let opts: options.EventHandlerOptions;
   if (typeof referenceOrOpts === "string") {
     path = normalizePath(referenceOrOpts);
@@ -598,17 +598,19 @@ export function makeEndpoint(
   eventType: string,
   opts: options.EventHandlerOptions,
   path: PathPattern,
-  instance: PathPattern
+  instance: PathPattern | Expression<string>
 ): ManifestEndpoint {
   const baseOpts = options.optionsToEndpoint(options.getGlobalOptions());
   const specificOpts = options.optionsToEndpoint(opts);
 
-  const eventFilters: Record<string, string> = {};
-  const eventFilterPathPatterns: Record<string, string> = {
+  const eventFilters: Record<string, string | Expression<string>> = {};
+  const eventFilterPathPatterns: Record<string, string | Expression<string>> = {
     // Note: Eventarc always treats ref as a path pattern
     ref: path.getValue(),
   };
-  if (instance.hasWildcards()) {
+  if (instance instanceof Expression) {
+    eventFilterPathPatterns.instance = instance;
+  } else if (instance.hasWildcards()) {
     eventFilterPathPatterns.instance = instance.getValue();
   } else {
     eventFilters.instance = instance.getValue();
@@ -632,6 +634,10 @@ export function makeEndpoint(
   };
 }
 
+function resolveInstancePattern(instance: PathPattern | Expression<string>): PathPattern {
+  return instance instanceof Expression ? new PathPattern(instance.value()) : instance;
+}
+
 /** @internal */
 export function onChangedOperation<Ref extends string>(
   eventType: string,
@@ -641,13 +647,18 @@ export function onChangedOperation<Ref extends string>(
   const { path, instance, opts } = getOpts(referenceOrOpts);
 
   const pathPattern = new PathPattern(path);
-  const instancePattern = new PathPattern(instance);
+  const instancePattern = instance instanceof Expression ? instance : new PathPattern(instance);
 
   // wrap the handler
   const func = (raw: CloudEvent<unknown>) => {
     const event = raw as RawRTDBCloudEvent;
     const instanceUrl = getInstance(event);
-    const params = makeParams(event, pathPattern, instancePattern) as unknown as ParamsOf<Ref>;
+    const resolvedInstancePattern = resolveInstancePattern(instancePattern);
+    const params = makeParams(
+      event,
+      pathPattern,
+      resolvedInstancePattern
+    ) as unknown as ParamsOf<Ref>;
     const databaseEvent = makeChangedDatabaseEvent(event, instanceUrl, params);
 
     const compatEvent = addV1Compat(databaseEvent, {
@@ -676,13 +687,18 @@ export function onOperation<Ref extends string>(
   const { path, instance, opts } = getOpts(referenceOrOpts);
 
   const pathPattern = new PathPattern(path);
-  const instancePattern = new PathPattern(instance);
+  const instancePattern = instance instanceof Expression ? instance : new PathPattern(instance);
 
   // wrap the handler
   const func = (raw: CloudEvent<unknown>) => {
     const event = raw as RawRTDBCloudEvent;
     const instanceUrl = getInstance(event);
-    const params = makeParams(event, pathPattern, instancePattern) as unknown as ParamsOf<Ref>;
+    const resolvedInstancePattern = resolveInstancePattern(instancePattern);
+    const params = makeParams(
+      event,
+      pathPattern,
+      resolvedInstancePattern
+    ) as unknown as ParamsOf<Ref>;
     const data = eventType === deletedEventType ? event.data.data : event.data.delta;
     const databaseEvent = makeDatabaseEvent(event, data, instanceUrl, params);