Fix NOTIFY calls without parameter (#25)

andywer · Aug 7, 2019 · 252cca3 · 252cca3
1 parent 736709c
commit 252cca3
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Showing 3 changed files with 40 additions and 7 deletions.
diff --git a/dist/index.d.ts b/dist/index.d.ts
@@ -59,7 +59,7 @@ export interface Subscriber {
     close(): Promise<void>;
     getSubscribedChannels(): string[];
     listenTo(channelName: string): Promise<pg.QueryResult> | undefined;
-    notify(channelName: string, payload: any): Promise<pg.QueryResult>;
+    notify(channelName: string, payload?: any): Promise<pg.QueryResult>;
     unlisten(channelName: string): Promise<pg.QueryResult> | undefined;
     unlistenAll(): Promise<pg.QueryResult>;
 }

diff --git a/src/index.ts b/src/index.ts
@@ -133,7 +133,7 @@ function forwardDBNotificationEvents (dbClient: pg.Client, emitter: TypedEventEm
 
     let payload
     try {
-      payload = notification.payload !== undefined ? parse(notification.payload) : undefined
+      payload = notification.payload ? parse(notification.payload) : undefined
     } catch (error) {
       error.message = `Error parsing PostgreSQL notification payload: ${error.message}`
       return emitter.emit("error", error)
@@ -181,7 +181,7 @@ export interface Subscriber {
     close(): Promise<void>;
     getSubscribedChannels(): string[];
     listenTo(channelName: string): Promise<pg.QueryResult> | undefined;
-    notify(channelName: string, payload: any): Promise<pg.QueryResult>;
+    notify(channelName: string, payload?: any): Promise<pg.QueryResult>;
     unlisten(channelName: string): Promise<pg.QueryResult> | undefined;
     unlistenAll(): Promise<pg.QueryResult>;
 }
@@ -298,10 +298,15 @@ function createPostgresSubscriber (connectionConfig?: pg.ClientConfig, options:
       subscribedChannels = [ ...subscribedChannels, channelName ]
       return dbClient.query(`LISTEN ${format.ident(channelName)}`)
     },
-    notify (channelName: string, payload: any) {
+    notify (channelName: string, payload?: any) {
       notificationLogger(`Sending PostgreSQL notification to "${channelName}":`, payload)
-      const serialized = serialize(payload)
-      return dbClient.query(`NOTIFY ${format.ident(channelName)}, ${format.literal(serialized)}`)
+
+      if (payload !== undefined) {
+        const serialized = serialize(payload)
+        return dbClient.query(`NOTIFY ${format.ident(channelName)}, ${format.literal(serialized)}`)
+      } else {
+        return dbClient.query(`NOTIFY ${format.ident(channelName)}`)
+      }
     },
     unlisten (channelName: string) {
       if (subscribedChannels.indexOf(channelName) === -1) {

diff --git a/test/integration.test.ts b/test/integration.test.ts
@@ -47,10 +47,38 @@ test("can listen and notify", async t => {
   }
 })
 
-test("can use custom `parse` function", async t => {
+test("can handle notification without payload", async t => {
   const notifications: PgParsedNotification[] = []
   const receivedPayloads: any[] = []
 
+  const hub = createPostgresSubscriber({ connectionString: "postgres://postgres:postgres@localhost:5432/postgres" })
+  await hub.connect()
+
+  try {
+    await hub.listenTo("test")
+    await hub.events.on("notification", (notification: PgParsedNotification) => notifications.push(notification))
+    await hub.notifications.on("test", (payload: any) => receivedPayloads.push(payload))
+
+    await hub.notify("test")
+    await delay(200)
+
+    t.deepEqual(hub.getSubscribedChannels(), ["test"])
+    t.deepEqual(notifications, [
+      {
+        channel: "test",
+        payload: undefined,
+        processId: notifications[0].processId
+      }
+    ])
+    t.deepEqual(receivedPayloads, [undefined])
+  } finally {
+    await hub.close()
+  }
+})
+
+test("can use custom `parse` function", async t => {
+  const notifications: PgParsedNotification[] = []
+
   const connectionString = "postgres://postgres:postgres@localhost:5432/postgres"
 
   const hub = createPostgresSubscriber(