Need more help on Snapshot testing in Postman

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1

My question: I can’t get snapshot testing to work for me. I’ve taken the snapshot response, I’ve created a mock server with that response. What should my test script look like? Is there a pre-requisite step?

I’ve already tried: I’ve gone to the topic Snapshot testing for APIs using Postman but could not understand what their test script included.

2

Hi @rnfasoliz

Have you added the snapshot response as an “example” of your mock server like this?

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Once you have this example you can add your tests in the “tests” tab to check the response data, for example;

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Hope this helps…

3

Thanks for the reply, but my goal is to validate the json schema and not only the status code. It seemed like snapshot testing is the key. I know how to make a snapshot and create a mock server with that snapshot, but not sure on how the test script is written in order to validate the json schema.

4

Here is a schema validation example for a REST API, it should give you the base structure for whats needed in your test tab;

const schema = {
    "type": "object",
    "properties": {
        "id": {
      "type": "integer"
    },
    "category": {
      "type": "object",
      "properties": {
        "id": {
          "type": "integer"
        },
        "name": {
          "type": "string"
        }
      },
      "required": [
        "id",
        "name"
      ]
    },
    "name": {
      "type": "string"
    },
    "photoUrls": {
      "type": "array",
      "items": [
        {
          "type": "string"
        }
      ]
    },
    "tags": {
      "type": "array",
      "items": [
        {
          "type": "object",
          "properties": {
            "id": {
              "type": "integer"
            },
            "name": {
              "type": "string"
            }
          },
          "required": [
            "id",
            "name"
          ]
        }
      ]
    },
    "status": {
      "type": "string"
    }
  },
  "required": [
    "id",
    "category",
    "name",
    "photoUrls",
    "tags",
    "status"
  ]
};

pm.test("Validating the API schema", () => {
    pm.response.to.have.jsonSchema(schema);
});
5

Awesome thank you for the help!

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