Merge pull request #3 from monikakonieczna/Task-3-Create-API-Tests-For-GET-All-Characters-Endpoint

Task 3: Create api tests for get all characters endpoint

Author: monikakonieczna

README.md

@@ -79,8 +79,30 @@ The following scripts are configured to run tests based on different groups:
 - test:filter_characters: Runs only the tests tagged as "filter_characters".
 - test:all: Runs all tests in the suite.
 
-### Run All Tests
+### Parametrize Tests with Jest
+When writing api tests, it is common to have multiple test cases that run the same logic with different inputs and expected outputs. Jest provides a convenient way to handle this by allowing parameterized tests. This technique allows you to define a single test structure and run it multiple times with different values, reducing redundancy and improving maintainability.
+#### How to Parametrize Tests in Jest
+In Jest, you can use the test.each or describe.each functions to define parameterized tests. These functions allow you to specify a table of inputs and expected results that the test framework will loop over, executing the test for each case.
+
+Example of describe.each
+
+- describe.each groups related test cases that share common input data
+- Each test case within the describe block runs with the provided parameters
 
-```shell
-npm test
 ```
+describe.each([
+  [99999, 404],
+  [0, 404],
+  [-1, 404],
+  [1.5, 404],
+])(
+  "Rick and Morty API Tests - Get One Character - Not Existing Character ID",
+  (id, statusCode) => {
+    it("Verifies that the API handle invalid character ID correctly", async () => {
+      const response = await makeRequest("get", `${BASE_URL}/character/${id}`);
+      assertStatusCode(response, statusCode);
+      validateNotFoundErrorMessage(response.body);
+    });
+  }
+);
+```

src/helpers/validateAllCharactersHelper.ts

@@ -0,0 +1,60 @@
+import * as fs from "fs";
+import * as path from "path";
+
+// Function to load JSON data from the file
+const loadJsonData = (fileName: string): any => {
+  const filePath = path.join(__dirname, "../test_data/get__all_characters", fileName);
+  const data = fs.readFileSync(filePath, "utf-8");
+  return JSON.parse(data);
+};
+
+// Load test data
+const validCharactersPage1 = loadJsonData("valid_characters_page_1.json");
+const validCharactersPage2 = loadJsonData("valid_characters_page_2.json");
+const validCharactersPage42 = loadJsonData("valid_characters_page_42.json");
+const notFoundPage = loadJsonData("not_found_page.json");
+
+/**
+ * A helper function to validate the structure of the response data for existing character - Page 1
+ * @param character
+ */
+export function validatePage1Structure(characters: Characters) {
+    expect(characters).toEqual(validCharactersPage1);
+}
+
+/**
+ * A helper function to validate the structure of the response data for existing character - Page 2
+ * @param character
+ */
+export function validatePage2Structure(characters: Characters) {
+    expect(characters).toEqual(validCharactersPage2);
+}
+
+/**
+ * A helper function to validate the structure of the response data for existing character - Page 42
+ * @param character
+ */
+export function validatePage42Structure(characters: Characters) {
+    expect(characters).toEqual(validCharactersPage42);
+}
+
+/**
+ * A helper function to validate that the response body contains the expected character data
+ * @param character
+ */
+
+export function validatePaginationInfo(characters: Characters, count: number, pages: number, next: string | null, prev: string | null) {
+  expect(characters.info.count).toEqual(count);
+  expect(characters.info.pages).toEqual(pages);
+  expect(characters.info.next).toEqual(next);
+  expect(characters.info.prev).toEqual(prev);
+
+}
+
+/**
+ * A helper function to verify the error response message for not existing page
+ * @param character
+ */
+export function validateNotFoundErrorMessage(error: Error) {
+  expect(error.message).toEqual(notFoundPage.message);
+}

src/helpers/validateCharacter.ts src/helpers/validateCharacterHelper.tssrc/helpers/validateCharacter.ts renamed to src/helpers/validateCharacterHelper.ts

@@ -0,0 +1,30 @@
+interface Characters {
+  info: {
+    count: number;
+    pages: number;
+    next: string;
+    prev: number;
+  };
+  results: [
+    {
+      id: number;
+      name: string;
+      status: string;
+      species: string;
+      type: string;
+      gender: string;
+      origin: {
+        name: string;
+        url: string;
+      };
+      location: {
+        name: string;
+        url: string;
+      };
+      image: string;
+      episode: Array<string>;
+      url: string;
+      created: string;
+    }
+  ];
+}

src/interfaces/characters.interface.ts

@@ -0,0 +1,3 @@
+{
+    "error": "There is nothing here"
+}