Allow nested filtering

lib/pubsub/getFilteredSubs-test.ts

@@ -7,22 +7,27 @@ import { collapseKeys, getFilteredSubs } from './getFilteredSubs'
 describe('collapseKeys', () => {
   it('makes the deep objects into dots', () => {
     assert.deepEqual(collapseKeys({}), {})
-    assert.deepEqual(collapseKeys({ a: 4, b: { c: 5, d: 'hi', e: { f: false } } }), {
-      a: 4,
-      'b.c': 5,
-      'b.d': 'hi',
-      'b.e.f': false,
-    })
-    assert.deepEqual(collapseKeys({ a: [1, 2, 3, { b: 4, c: [], d: null, e: undefined }] }), {
-      'a.0': 1,
-      'a.1': 2,
-      'a.2': 3,
-      'a.3.b': 4,
-    })
+    assert.deepEqual(
+      collapseKeys({ a: 4, b: { c: 5, d: 'hi', e: { f: false } } }),
+      {
+        a: 4,
+        'b.c': 5,
+        'b.d': 'hi',
+        'b.e.f': false,
+      },
+    )
+    assert.deepEqual(
+      collapseKeys({ a: [1, 2, 3, { b: 4, c: [], d: null, e: undefined }] }),
+      {
+        'a.0': 1,
+        'a.1': 2,
+        'a.2': 3,
+        'a.3.b': 4,
+      },
+    )
   })
 })
 
-
 // since we're not resetting the db every time we need to change this
 let count = 1
 const makeTopic = () => `topic-${count++}`
@@ -53,7 +58,13 @@ describe('getFilteredSubs', () => {
     }
 
     await server.models.subscription.put(subscription)
-    assert.containSubset(await getFilteredSubs({ server, event: { topic, payload: { language: 'en' } } }), [{ topic, id: '1' }])
+    assert.containSubset(
+      await getFilteredSubs({
+        server,
+        event: { topic, payload: { language: 'en' } },
+      }),
+      [{ topic, id: '1' }],
+    )
   })
 
   it('can match on payload', async () => {
@@ -74,8 +85,60 @@ describe('getFilteredSubs', () => {
 
     await server.models.subscription.put(subscription)
 
-    assert.containSubset(await getFilteredSubs({ server, event: { topic, payload: { language: 'en' } } }), [{ topic, id: '2' }])
-    assert.deepEqual(await getFilteredSubs({ server, event: { topic, payload: { language: 'en-gb' } } }), [])
+    assert.containSubset(
+      await getFilteredSubs({
+        server,
+        event: { topic, payload: { language: 'en' } },
+      }),
+      [{ topic, id: '2' }],
+    )
+    assert.deepEqual(
+      await getFilteredSubs({
+        server,
+        event: { topic, payload: { language: 'en-gb' } },
+      }),
+      [],
+    )
+  })
+
+  it('can match on nested payload', async () => {
+    const topic = makeTopic()
+    const server = await mockServerContext()
+    const subscription = {
+      id: '2',
+      topic,
+      filter: { meta: { user: 'foo' }, message: { content: 'hi' } },
+      subscriptionId: '2',
+      subscription: {} as any,
+      connectionId: 'abcd',
+      connectionInitPayload: {},
+      requestContext: {} as any,
+      ttl: Math.floor(Date.now() / 1000) + 100000,
+      createdAt: Date.now(),
+    }
+
+    await server.models.subscription.put(subscription)
+
+    assert.containSubset(
+      await getFilteredSubs({
+        server,
+        event: {
+          topic,
+          payload: { meta: { user: 'foo' }, message: { content: 'hi' } },
+        },
+      }),
+      [{ topic, id: '2' }],
+    )
+    assert.deepEqual(
+      await getFilteredSubs({
+        server,
+        event: {
+          topic,
+          payload: { meta: { user: 'lol' }, message: { content: 'bye' } },
+        },
+      }),
+      [],
+    )
   })
 
   it('can match on no payload', async () => {

lib/pubsub/getFilteredSubs.ts

@@ -2,7 +2,13 @@
 import { collect } from 'streaming-iterables'
 import { ServerClosure, Subscription } from '../types'
 
-export const getFilteredSubs = async ({ server, event }: { server: Omit<ServerClosure, 'gateway'>, event: { topic: string, payload?: Record<string, any> } }): Promise<Subscription[]> => {
+export const getFilteredSubs = async ({
+  server,
+  event,
+}: {
+  server: Omit<ServerClosure, 'gateway'>
+  event: { topic: string, payload?: Record<string, any> }
+}): Promise<Subscription[]> => {
   if (!event.payload || Object.keys(event.payload).length === 0) {
     server.log('getFilteredSubs', { event })
 
@@ -18,18 +24,35 @@ export const getFilteredSubs = async ({ server, event }: { server: Omit<ServerCl
   const flattenPayload = collapseKeys(event.payload)
 
   const filterExpressions: string[] = []
-  const expressionAttributeValues: { [key: string]: string | number | boolean } = {}
+  const expressionAttributeValues: {
+    [key: string]: string | number | boolean
+  } = {}
   const expressionAttributeNames: { [key: string]: string } = {}
 
   let attributeCounter = 0
   for (const [key, value] of Object.entries(flattenPayload)) {
     const aliasNumber = attributeCounter++
-    expressionAttributeNames[`#${aliasNumber}`] = key
+    const keyParts = key.split('.')
+    const keyPartsAttributeName = keyParts
+      .map((part, index) => `#${aliasNumber + index}`)
+      .join('.')
+    key.split('.').forEach((keyPart, index) => {
+      expressionAttributeNames[`#${aliasNumber + index}`] = keyPart
+      attributeCounter += index
+    })
     expressionAttributeValues[`:${aliasNumber}`] = value
-    filterExpressions.push(`(#filter.#${aliasNumber} = :${aliasNumber} OR attribute_not_exists(#filter.#${aliasNumber}))`)
+
+    filterExpressions.push(
+      `(#filter.${keyPartsAttributeName} = :${aliasNumber} OR attribute_not_exists(#filter.${keyPartsAttributeName}))`,
+    )
   }
 
-  server.log('getFilteredSubs', { event, expressionAttributeNames, expressionAttributeValues, filterExpressions })
+  server.log('getFilteredSubs', {
+    event,
+    expressionAttributeNames,
+    expressionAttributeValues,
+    filterExpressions,
+  })
 
   const iterator = server.models.subscription.query({
     IndexName: 'TopicIndex',
@@ -54,7 +77,11 @@ export const collapseKeys = (
 ): Record<string, number | string | boolean> => {
   const record = {}
   for (const [k1, v1] of Object.entries(obj)) {
-    if (typeof v1 === 'string' || typeof v1 === 'number' || typeof v1 === 'boolean') {
+    if (
+      typeof v1 === 'string' ||
+      typeof v1 === 'number' ||
+      typeof v1 === 'boolean'
+    ) {
       record[k1] = v1
       continue
     }