In an API-first design lifecycle, you may be designing a new feature that depends on new API endpoints, but another team is responsible for implementing those endpoints, and aren't finished yet. Instead of being blocked by this, you can use a mock server, which will return sample data for requests to the API's endpoints, simulating the behavior of a real API. You can then use the mock server to test your API, before it's even implemented by the other team.
Before creating a gRPC mock server, you must have an API definition. This can either be an API in your workspace, a protobuf (protocol buffer) file you want to import, or you can create a new API using the Postman API Builder.
To create the gRPC mock server, do the following:
.proto
file.The mock server will be automatically generated, and ready for use. The request URL will be a server name beginning with a random name and ending in .srv.pstmn.io
. Select methods, then select Invoke, and your request will receive responses with random values.
The mock server will dynamically update based on changes to your protobuf API. If changes are made in API Builder to the protobuf API, requests to the mock server will automatically implement the changes.
Each time you make a request against the mock server, different random data will be returned. However, if you are writing tests, you might need to get the same response every time. This is possible using the seed metadata in each response. The seed is a random number in the response metadata. If you pass the seed in a request, the same response will be returned each time.
To pass seed data, do the following:
seed
.
seed
with the value of the seed.
The mock servers in gPRC are independent of the mock server feature in Postman. See setting up mock servers for more information about using mock servers for your other APIs.
Last modified: 2022/09/15
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