Read

Jump to the Code block for a combined complete example.

Create a document record

The following example demonstrates reading a document record with a JSON helper library. In Aerospike, JSON documents are handled as a Collection Data Type (CDT). A JSON object is equivalent to a map, and a JSON array is equivalent to a list.

In this example, we create the following JSON document:

employees = [{"id": "09", "name": "Nitin", "department": "Finance"},
             {"id": "10", "name": "Jonathan", "department": "Human Resources"},
             {"id": "11", "name": "Caitlin", "department": "Engineering"}]

The JSON document is added to a bin called employees which is of data type list. There are some advantages to holding an entire document in a single bin, rather than spreading out the document’s fields over multiple bins. There is less metadata overhead when namespaces contain fewer, larger bins.

Setup

Import the necessary helpers, create a client connection, and create a key.

import { readFile } from "node:fs/promises";

const Aerospike = await import("aerospike");
const maps = Aerospike.maps;

// Set hosts to your server's address and port
const config = { hosts: "YOUR_HOST_ADDRESS:YOUR_PORT" };

// Create a key
const key = new Aerospike.Key("test", "demo", 5001);

// Establishes a connection to the server
const client = await Aerospike.connect(config);

Read

Read the name field from the third record in the map list.

// Get 'name' field from 3rd employee record
const ops = [
  maps
    .getByKey("employees", "name")
    .withContext((ctx) => ctx.addListIndex(2))
    .andReturn(maps.returnType.VALUE),
];

const result = await client.operate(key, ops);
console.info("Name of 3rd employee: ", result.bins.employees);

Code block

Expand this section for a single code block to read a document record.

const Aerospike = await import("aerospike");

import { readFile } from "node:fs/promises";

const maps = Aerospike.maps;

// Set hosts to your server's address and port
const config = { hosts: "YOUR_HOST_ADDRESS:YOUR_PORT" };

// Create a key
const key = new Aerospike.Key("test", "demo", 5001);

// Establishes a connection to the server
const client = await Aerospike.connect(config);

// Get 'name' field from 3rd employee record
const ops = [
  maps
    .getByKey("employees", "name")
    .withContext((ctx) => ctx.addListIndex(2))
    .andReturn(maps.returnType.VALUE),
];

const result = await client.operate(key, ops);
console.info("Name of 3rd employee: ", result.bins.employees);

await client.close();