If you would like to connect to IBM Cloud Object Storage but don’t know how to code it, you can use Postman to help you. 

In this blog post, I’ll show you how you can validate a connection to IBM Cloud Object Storage using Postman and verify the code needed to be used in your application. We will use Bearer Token and AWS Signature as authentication methods.

Using Bearer Token

First of all, ensure that you have an API key. You can get one from IBM Cloud Identity and Access Management (IAM).

1. Request an IAM token by using an API key:

   curl -X "POST" "https://iam.cloud.ibm.com/identity/token" \
        -H 'Accept: application/json' \
        -H 'Content-Type: application/x-www-form-urlencoded' \
        --data-urlencode "apikey={api-key}" \
        --data-urlencode "response_type=cloud_iam" \
        --data-urlencode "grant_type=urn:ibm:params:oauth:grant-type:apikey"

2. After you press enter, the command returns the token that you need. The token is inside " " between access_token and refresh_token:

   Note: I hid some characters for security reasons.

3. Open the Postman software and fill out the options:
   • Put your endpoint and bucket: https://<endpoint-url>/<bucket-name
   • In the Authorization tab, select Oauth 2.0 and Request Headers.
   • Put your token in that field.
   • Click on the Send button.

4. The Status will return code 200, and that means the connection was successful. Next, click the Code button:

5. On the left side, you have options for different programming languages. You can choose your desired language and Postman will display the code used on the right side:

Using AWS Signature

To use AWS Signature, you will need access_key_id and secret_access_key. You can get those values on your instance of IBM Cloud Object Storage (you will need to create an instance if you don’t have one).

1. Create service credentials (if you already have these, go directly to Postman in Step 2):
   • Log in to the IBM Cloud console and navigate to your instance of Object Storage.
   • In the side navigation, click Service Credentials.
   • Click New credential and provide the necessary information.
   • Click Add to generate the service credential.
2. In Postman, fill out the following options:
   • Enter your endpoint and bucket: https://<endpoint-url>/<bucket-name>
   • In the Authorization tab, select AWS Signature.
   • Enter your values in the AccessKey and SecretKey fields. 

3. The Status will return code 200, and that means the connection was successful. Next, click the Code button:

4. On the left side, you have options for different programming languages. You can choose your desired language and Postman will display the code used on the right side:

Learn more

Many programmers don’t know how to add a method to their application to communicate with IBM Cloud Storage or another S3 service. Using Postman, you can test and validate the authentication method and consequently find out how Postman performs this operation and use it as an example for your source code.

• IBM Cloud Object Storage
• Postman
• IBM Developer: Object Storage
• What is Object Storage?