Wherobots TypeScript SDK

TypeScript SDK for interacting with WherobotsDB. This package implements a Node.js client that programmatically connects to a WherobotsDB runtime and execute Spatial SQL queries.

Prerequisites

1. Node.js version 18 or higher
2. TypeScript version 5.x (if using TypeScript)
3. A Wherobots API Key. See the Wherobots API Key Documentation for instructions on how to generate a key.

Installation

$ npm install wherobots-sql-driver

Usage

Example: Executing SQL statement and printing results

This example follows the typical pattern of an async function to establish the connection to WherobotsDB. After establishing this connection, you can call async methods to execute SQL queries through this connection.

import { Connection, Runtime } from "wherobots-sql-driver";

(async () => {
  const conn = await Connection.connect({
    // replace "YOUR-WHEROBOTS-API-KEY" with the key created above
    // or alternatively the key can be set with the `WHEROBOTS_API_KEY` environment variable
    apiKey: "YOUR-WHEROBOTS-API-KEY",
    runtime: Runtime.SEDONA,
  });
  const results = await conn.execute("SHOW SCHEMAS IN wherobots_open_data");
  console.log(JSON.stringify(results.toArray(), null, 2));
  conn.close();
})();

Running this example returns the results of the query as JSON:

[
  {
    "namespace": "overture"
  },
  {
    "namespace": "overture_2024_02_15"
  },
  {
    "namespace": "overture_2024_05_16"
  },
  {
    "namespace": "overture_2024_07_22"
  },
  {
    "namespace": "test_db"
  }
]

Code example explanation

1. Calling Connection.connect() asynchronously establishes a SQL Session connection in Wherobots Cloud and returns a Connection instance.
2. Calling the connection's execute() methods runs the given SQL statement and asynchronously returns the result as an Apache Arrow Table instance.
3. The Arrow Table instance can be converted to a primitive by calling toArray(), and then printed to the console as formatted JSON with JSON.stringify().
4. Calling the connection's close() method tears down the SQL Session connection.

Running the example - JavaScript

1. Paste the contents of the above code example into a file called wherobots-example.js
2. Run the example with: node wherobots-example.js

Running the example - TypeScript

1. Paste the contents of the above code example into a file called wherobots-example.ts
2. Run the example with: npx tsx wherobots-example.ts

Runtime and region selection

You can chose the Wherobots runtime you want to use using the runtime parameter, passing in one of the Runtime enum values. For more information on runtime sizing and selection, please consult the Wherobots product documentation.

Additional parameters to connect()

The Connection.connect() function can take the following additional options:

• resultsFormat: one of the ResultsFormat enum values; Arrow encoding is the default and most efficient format for receiving query results.

  • NOTE: currently only Arrow encoding is supported

• dataCompression: one of the DataCompression enum values; Brotli compression is the default and the most efficient compression algorithm for receiving query results.

  • NOTE: currently only Brotli compression is supported

• geometryRepresentation: one of the GeometryRepresentation enum values; selects the encoding of geometry columns returned to the client application. The default is EWKT (string) and the most convenient for human inspection while still being usable by geospatial data manipulation libraries.

• region: Currently, the only supported Wherobots compute region is aws-us-west-2, in AWS's Oregon (us-west-2) region.

Additional parameters to execute()

The Connection#execute method can take an optional second argument, options:

• options.signal: an AbortSignal which can be used to cancel the execution (optional)