Some refactoring.

Author: Simon Prickett

examples/search-json.js

@@ -2,50 +2,63 @@
 
 import { createClient, SchemaFieldTypes, AggregateGroupByReducers, AggregateSteps } from 'redis';
 
-async function searchPlusJson() {
+async function searchJSON() {
   const client = createClient();
 
   await client.connect();
 
-  // Create an index
-  await client.ft.create('users', {
-    '$.name': {
-      type: SchemaFieldTypes.TEXT,
-      SORTABLE: 'UNF'
-    },
-    '$.age': SchemaFieldTypes.NUMERIC,
-    '$.coins': SchemaFieldTypes.NUMERIC
-  }, {
-    ON: 'JSON'
-  });
+  // Create an index.
+  try {
+    await client.ft.create('idx:users', {
+      '$.name': {
+        type: SchemaFieldTypes.TEXT,
+        SORTABLE: 'UNF'
+      },
+      '$.age': SchemaFieldTypes.NUMERIC,
+      '$.coins': SchemaFieldTypes.NUMERIC
+    }, {
+      ON: 'JSON',
+      PREFIX: 'noderedis:users'
+    });
+  } catch (e) {
+    if (e.message === 'Index already exists') {
+      console.log('Index exists already, skipped creation.');
+    } else {
+      // Something went wrong, perhaps RediSearch isn't installed...
+      console.error(e);
+      process.exit(1);
+    }
+  }
 
-  // Add some users
+  // Add some users.
   await Promise.all([
-    client.json.set('users:1', '$', {
+    client.json.set('noderedis:users:1', '$', {
       name: 'Alice',
       age: 32,
       coins: 100
     }),
-    client.json.set('users:2', '$', {
+    client.json.set('noderedis:users:2', '$', {
       name: 'Bob',
       age: 23,
       coins: 15
     })
   ]);
 
   // Search all users under 30
+  // https://oss.redis.com/redisearch/Commands/#ftsearch
   // TODO: why "$.age:[-inf, 30]" does not work?
   console.log(
-    await client.ft.search('users', '*')
+    await client.ft.search('idx:users', '*')
   );
   // {
   //   total: 1,
   //   documents: [...]
   // }
 
-  // Some aggregrations...
+  // Some aggregrations, what's the average age and total number of coins...
+  // https://oss.redis.com/redisearch/Commands/#ftaggregate
   console.log(
-    await client.ft.aggregate('users', '*', {
+    await client.ft.aggregate('idx:users', '*', {
       STEPS: [{
         type: AggregateSteps.GROUPBY,
         REDUCE: [{
@@ -71,4 +84,4 @@ async function searchPlusJson() {
   await client.quit();
 }
 
-searchPlusJson();
+searchJSON();