Check out these resources for reading up and learning about how to do API Integrations in Salesforce with other systems.
- Lightning Platform API Basics – Trailhead
- API Integration Services – Trailhead
- Integration in Salesforce using Standard REST API and Custom REST API with Postman – Video
- Connect to Salesforce using Postman and Connected App – Video
- Get and Post data from and to Salesforce using REST API via connected app using Postman – Video
- How to connect to Salesforce with Postman – Blog
- Setting up Postman to Access Salesforce APIs – Blog
- Creating custom REST Endpoints in Salesforce – Passing data into Salesforce – Custom Rest API – Video
- APIs and Integration for the Salesforce Platform – Video
- Obtain Access & Refresh tokens from Salesforce REST API – Medium
- Design Solutions with Salesforce APIs – Trailhead
- REST API Developer Guide – Salesforce Developer Guide
- Explore Integration Patterns and Practices – Trailhead
- Comparison of Salesforce REST API Composite Resources – Video
To update Salesforce records using Standard Salesforce API but without using the Salesforce Record Id, use External Id instead – Salesforce Developer Guide
Some tools to help with your Apex API Integration needs. For complex JSON structures, you can use JSON2Apex. This tool generates strongly typed Apex code for parsing a JSON structure. You simply paste in the JSON, and the tool generates the necessary Apex code for you. Learn more: