Use UpdateBasePathMapping with an AWS SDK or CLI

To change the base path for a custom domain name

Command:

aws apigateway update-base-path-mapping --domain-name api.domain.tld --base-path prod --patch-operations op='replace',path='/basePath',value='v1'

Output:

{
    "basePath": "v1",
    "restApiId": "1234123412",
    "stage": "api"
}

require 'vendor/autoload.php';

use Aws\ApiGateway\ApiGatewayClient;
use Aws\Exception\AwsException;


/* ////////////////////////////////////////////////////////////////////////////
 *
 * Purpose: Updates the base path mapping for a custom domain name
 * in Amazon API Gateway.
 *
 * Inputs:
 * - $apiGatewayClient: An initialized AWS SDK for PHP API client for
 *   API Gateway.
 * - $basePath: The base path name that callers must provide as part of the
 *   URL after the domain name.
 * - $domainName: The custom domain name for the base path mapping.
 * - $patchOperations: The base path update operations to apply.
 *
 * Returns: Information about the updated base path mapping, if available;
 * otherwise, the error message.
 * ///////////////////////////////////////////////////////////////////////// */

function updateBasePathMapping(
    $apiGatewayClient,
    $basePath,
    $domainName,
    $patchOperations
) {
    try {
        $result = $apiGatewayClient->updateBasePathMapping([
            'basePath' => $basePath,
            'domainName' => $domainName,
            'patchOperations' => $patchOperations
        ]);
        return 'The updated base path\'s URI is: ' .
            $result['@metadata']['effectiveUri'];
    } catch (AwsException $e) {
        return 'Error: ' . $e['message'];
    }
}

function updateTheBasePathMapping()
{
    $patchOperations = array([
        'op' => 'replace',
        'path' => '/stage',
        'value' => 'stage2'
    ]);

    $apiGatewayClient = new ApiGatewayClient([
        'profile' => 'default',
        'region' => 'us-east-1',
        'version' => '2015-07-09'
    ]);

    echo updateBasePathMapping(
        $apiGatewayClient,
        '(none)',
        'example.com',
        $patchOperations
    );
}

// Uncomment the following line to run this code in an AWS account.
// updateTheBasePathMapping();