WireMock

WireMock is for me an alternative for Postman, especially when I don’t want to share 3rd party APIs over the network (even with private token). Stubbing requests is quite easy, we can use a standalone version of WireMock and  keep all stubs in mappings (stubbing GET requests is even simpler we can just put responses in __files/path/to/resource/home.html).

Then run from folder we have mappings or __files :
java -jar wiremock-standalone-2.21.0.jar --port 9999
The sample mapping for POST api request can look like:

# Response we want to get
{
  "id": 123,
  "login": "test@example.com",
  "country": "us",
  "status": "active,
  "messages": [
    {
      "id": 56,
      "text": "Product was saved"
    },
    {
      "id": 59,
      "text": "Email has been sent to customer"
    }
  ]
}

# Mapping in file mappings/login.json
{
  "request": {
    "method": "POST",
    "url": "/api/login"
  },
  "response": {
    "status": 200,
    "body": "{\n  \"id\": 123,\n  \"login\": \"test@example.com\",\n  \"country\": \"us\",\n  \"status\": \"active,\n  \"messages\": [\n    {\n      \"id\": 56,\n      \"text\": \"Product was saved\"\n    },\n    {\n      \"id\": 59,\n      \"text\": \"Email has been sent to customer\"\n    }\n  ]\n}",
    "headers": {
      "Content-Type": "application/json"
    }
  }
}