Adds RediSearch demo.

Author: Simon Prickett

examples/README.md

@@ -2,14 +2,15 @@
 
 This folder contains example scripts showing how to use Node Redis in different scenarios.
 
-| File Name                   | Description                                                                        |
-|-----------------------------|------------------------------------------------------------------------------------|
-| `blocking-list-pop.js`      | Block until an element is pushed to a list                                         |
-| `command-with-modifiers.js` | Define a script that allows to run a command with several modifiers                |
-| `connect-as-acl-user.js`    | Connect to Redis 6 using an ACL user                                               |
-| `lua-multi-incr.js`         | Define a custom lua script that allows you to perform INCRBY on multiple keys      |
-| `search+json.js`            | Use [Redis Search](https://redisearch.io/) and [Redis JSON](https://redisjson.io/) |
-| `set-scan.js`               | An example script that shows how to use the SSCAN iterator functionality           |
+| File Name                   | Description                                                                                                    |
+|-----------------------------|----------------------------------------------------------------------------------------------------------------|
+| `blocking-list-pop.js`      | Block until an element is pushed to a list                                                                     |
+| `command-with-modifiers.js` | Define a script that allows to run a command with several modifiers                                            |
+| `connect-as-acl-user.js`    | Connect to Redis 6 using an ACL user                                                                           |
+| `lua-multi-incr.js`         | Define a custom lua script that allows you to perform INCRBY on multiple keys                                  |
+| `search-hashes.js`          | Uses [RediSearch](https://redisearch.io) to index and search data in hashes                                    |
+| `search+json.js`            | Uses [RediSearch](https://redisearch.io/) and [RedisJSON](https://redisjson.io/) to index and search JSON data |
+| `set-scan.js`               | An example script that shows how to use the SSCAN iterator functionality                                       |
 
 ## Contributing
 

examples/search-hashes.js

@@ -0,0 +1,82 @@
+// This example demonstrates how to use RediSearch to index and query data 
+// stored in Redis hashes.
+
+import { createClient, SchemaFieldTypes } from 'redis';
+
+async function searchHashes() {
+  const client = createClient();
+
+  await client.connect();
+
+  // Create an index...
+  try {
+    // Documentation: https://oss.redis.com/redisearch/Commands/#ftcreate
+    await client.ft.create('idx:animals', {
+      name: {
+        type: SchemaFieldTypes.TEXT,
+        sortable: true
+      },
+      species: SchemaFieldTypes.TAG,
+      age: SchemaFieldTypes.NUMERIC
+    }, {
+      ON: 'HASH',
+      PREFIX: 'noderedis:animals'
+    });
+  } 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 sample data...
+  await Promise.all([
+    client.hSet('noderedis:animals:1', {name: 'Fluffy', species: 'cat', age: 3}),
+    client.hSet('noderedis:animals:2', {name: 'Ginger', species: 'cat', age: 4}),
+    client.hSet('noderedis:animals:3', {name: 'Rover', species: 'dog', age: 9}),
+    client.hSet('noderedis:animals:4', {name: 'Fido', species: 'dog', age: 7})
+  ]);
+
+  // Perform a search query, find all the dogs...
+  // Documentation: https://oss.redis.com/redisearch/Commands/#ftsearch
+  // Query synatax: https://oss.redis.com/redisearch/Query_Syntax/
+  const results = await client.ft.search('idx:animals', '@species:{dog}');
+
+  // results:
+  // {
+  //   total: 2,
+  //   documents: [
+  //     { 
+  //       id: 'noderedis:animals:4',
+  //       value: {
+  //         name: 'Fido',
+  //         species: 'dog',
+  //         age: '7'
+  //       }
+  //     },
+  //     {
+  //       id: 'noderedis:animals:3',
+  //       value: {
+  //         name: 'Rover',
+  //         species: 'dog',
+  //         age: '9'
+  //       }
+  //     }
+  //   ]
+  // }
+ 
+  console.log(`Results found: ${results.total}.`);
+
+  for (const doc of results.documents) {
+    // noderedis:animals:4: Fido
+    // noderedis:animals:3: Rover
+    console.log(`${doc.id}: ${doc.value.name}`);
+  }
+
+  await client.quit();
+}
+
+searchHashes();