In API testing, environment variables, collection variables, and global variables are used to store values that can be reused across multiple requests, environments, or test scenarios. They help make API tests more dynamic and adaptable. Here’s an explanation of each type:
1. Environment Variables
- Definition: These variables are specific to a particular environment, such as development, staging, or production.
- Scope: Only accessible within the specific environment for which they are defined.
- Use Case: Ideal for storing environment-specific details like base URLs, authentication tokens, or database credentials.
- Example:
- In a development environment,
{{base_url}}might behttps://dev.api.example.com. - In a production environment,
{{base_url}}could behttps://api.example.com.
2. Collection Variables
- Definition: Variables that are defined within a collection and are shared across all requests in that collection.
- Scope: Available only to the requests inside the collection where they are defined.
- Use Case: Useful for values that are consistent across multiple requests in the same collection, like API keys or paths common to a set of related requests.
- Example:
- A collection for a user management API might use
{{api_key}}for authentication, which would be the same for all endpoints like/users,/users/{id}, etc.
3. Global Variables
- Definition: Variables that are accessible across all collections and environments in the workspace.
- Scope: They have the broadest scope and can be used in any request, regardless of the collection or environment.
- Use Case: Suitable for values that are universally applicable across multiple collections, such as user-specific credentials or test constants.
- Example: A global variable
{{username}}might be used for authentication across different APIs or collections.
Each type of variable can be used to make your API testing scripts more modular and reusable, improving flexibility when running tests across different setups or environments.