Resource Owner Password Credentials Flow: To Configure a REST Application to Use OAuth 2.0

This activity will walk you through the process of configuring a Postman collection to use the OAuth 2.0 authorization for the requests to MYOB Acumatica.

Story

Suppose that you need to configure the MyStoreIntegration application, which is a Postman collection, to use the Resource Owner Password Credentials flow.

Process Overview

You will connect to the token endpoint, pass the client ID and client secret in the authorization header, and request access to the web service APIs (that is, you will request the api scope). You will receive the access token from MYOB Acumatica to use it in subsequent requests to MYOB Acumatica. You will not request the refresh token, which the client application can use to request a new access token when the access token has expired.

System Preparation

Before you begin performing the steps of this activity, do the following:

1. Deploy a new MYOB Acumatica instance with the T100 dataset. For details on deploying an instance, see Instance Deployment: To Deploy an Instance with Demo Data.
2. To sign in to the instance in the client application, use the tenant name (which you specified when you created the instance) and the MYSTORE branch.
3. Complete the following prerequisite activity: Registration of an OAuth 2.0 or OIDC ApplicationActivity 1.1.1: To Register the Application in MYOB Acumatica.

Step: Configuring a Postman Collection

To configure a Postman collection to use the OAuth 2.0 authorization in MYOB Acumatica, do the following:

1. If you use a self-signed certificate for HTTPS, in Postman settings, turn off SSL certificate verification.
2. In Postman, create a collection.
3. On the Authorization tab of the collection properties window, which opens when the collection has been created, select the following values:
   • Auth Type: OAuth 2.0
   • Add auth data to: Request Headers
4. In the Configure New Token section, specify the following values:
   • Token Name: MyStoreIntegration
   • Grant Type: Password Credentials
   • Access Token URL: The token endpoint address, such as https://localhost/MyStoreInstance/identity/connect/token
   • Username: admin
   • Password: The password for the admin user
   • Client ID: The client ID of the application, which you can copy from the Client ID box on the Connected Applications (SM303010) form for the MyStoreIntegration client (which you have created in Registration of an OAuth 2.0 or OIDC ApplicationActivity 1.1.1: To Register the Application in MYOB Acumatica)
   • Client Secret: The client secret that you have received and saved during the registration of the MyStoreIntegration client on the Connected Applications form
   • Scope: api
   • Client Authentication: Send client credentials in body
5. Click Get New Access Token. Once the token is received, the Manage Access Tokens dialog box opens.
   Tip: In certain versions of Postman, the approach described in this section does not work. Instead of this approach, you can send a direct POST request to the token endpoint. In the body of the request, you should pass the client ID, the client secret, MYOB Acumatica username and password, the type of the authorization flow, and the requested scope. For details about the parameters passed in the request body, see Resource Owner Password Credentials Flow: Obtaining of an Access Token.
6. In the Manage Access Tokens dialog box, click Use Token.
7. On the toolbar of the collection properties window, click Save.