feat: add a generic API request interface

This public, generic interface is useful for making arbitrary API calls to the EasyPost API that
are not yet supported by the client library's services. When possible, the service for your use case
should be used instead as it provides a more convenient and higher-level interface depending on the endpoint.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: Justintime50

src/easypost.js

@@ -115,6 +115,23 @@ export default class EasyPostClient {
     this.responseHooks = [];
   }
 
+  /**
+   * Make an API call to the EasyPost API.
+   *
+   * This public, generic interface is useful for making arbitrary API calls to the EasyPost API that
+   * are not yet supported by the client library's services. When possible, the service for your use case
+   * should be used instead as it provides a more convenient and higher-level interface depending on the endpoint.
+   * @param {string} method - The HTTP method to use (e.g. 'get', 'post', 'put', 'patch', 'del').
+   * @param {string} endpoint - The API endpoint to call (e.g. '/addresses').
+   * @param {Object} [params] - The parameters to send with the request.
+   * @returns {Promise<Object>} The response from the API call.
+   */
+  async makeApiCall(method, endpoint, params = {}) {
+    const response = await this._request(endpoint, method, params);
+
+    return response.body;
+  }
+
   /**
    * Create a copy of an {@link EasyPostClient} with overridden options.
    * @param {EasyPostClient} client The `EasyPostClient` instance to clone.

test/cassettes/EasyPost_3093958733/makes-an-API-call-using-the-generic-makeApiCall-method_2342601902/recording.har

@@ -147,4 +147,14 @@ describe('EasyPost', function () {
     expect(responseConfig1).to.be.null;
     expect(responseConfig2).to.be.null;
   });
+
+  it('makes an API call using the generic makeApiCall method', async function () {
+    const response = await client.makeApiCall(EasyPostClient.METHODS.GET, '/addresses', {
+      page_size: 1,
+    });
+
+    expect(response.addresses).to.be.an('array');
+    expect(response.addresses.length).to.equal(1);
+    expect(response.addresses[0].object).to.equal('Address');
+  });
 });

test/services/easypost.test.js

@@ -136,4 +136,16 @@ export default class EasyPost {
    * Clears all response hooks from the EasyPost client.
    */
   public clearResponseHooks(): void;
+  /**
+   * Make an API call to the EasyPost API.
+   *
+   * This public, generic interface is useful for making arbitrary API calls to the EasyPost API that
+   * are not yet supported by the client library's services. When possible, the service for your use case
+   * should be used instead as it provides a more convenient and higher-level interface depending on the endpoint.
+   */
+  public makeApiCall(
+    method: 'get' | 'post' | 'put' | 'patch' | 'del',
+    endpoint: string,
+    params?: Record<string, any>,
+  ): Promise<Record<string, any>>;
 }