No dependency runtime validators (#37)

* Added jest for automated testing

* Created BaseValidator and CatalogValidator classes

* Updated exports

* Created basic jest test for Catalog objects

* Added github action to run jest tests

Author: NandaScott

.github/workflows/jest.yml

@@ -0,0 +1,11 @@
+name: Jest CI
+on: push
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install modules
+        run: npm i
+      - name: Run tests
+        run: npm run test

jest.config.js

@@ -0,0 +1,6 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} */
+module.exports = {
+  preset: "ts-jest",
+  testEnvironment: "node",
+  modulePaths: ["<rootDir>"],
+};

package-lock.json

@@ -6,7 +6,7 @@
   "scripts": {
     "qa": "npm run check:types && npm run lint && npm run test",
     "lint": "eslint",
-    "test": "",
+    "test": "jest",
     "check:types": "tsc --noEmit"
   },
   "files": [
@@ -30,10 +30,13 @@
     "typescript"
   ],
   "devDependencies": {
+    "@types/jest": "^29.5.12",
     "@typescript-eslint/eslint-plugin": "^6.7.4",
     "@typescript-eslint/parser": "^6.7.4",
     "eslint": "^8.51.0",
+    "jest": "^29.7.0",
     "prettier": "^3.0.3",
+    "ts-jest": "^29.1.5",
     "tslib": "^2.6.2",
     "typescript": "^5.2.2"
   }

package.json

@@ -0,0 +1,35 @@
+import { ScryfallCatalog } from "src/objects";
+import CatalogValidator from "src/validators/objects/Catalog/CatalogValidator";
+
+const cardNamesRequest: Promise<ScryfallCatalog> = fetch("https://api.scryfall.com/catalog/card-names").then((resp) =>
+  resp.json(),
+);
+
+describe("Catalog", () => {
+  test("has expected fields", async () => {
+    const cardNamesCatalog = await cardNamesRequest;
+    const goodValidator = new CatalogValidator(cardNamesCatalog);
+
+    expect(goodValidator.validKeys).toBe(true);
+  });
+
+  test("expected fields are expected type", async () => {
+    const cardNamesCatalog = await cardNamesRequest;
+    const validator = new CatalogValidator(cardNamesCatalog);
+    expect(validator.validKeyType).toBe(true);
+  });
+
+  test("has no unexpected fields", async () => {
+    const cardNamesCatalog = await cardNamesRequest;
+    const mockKeyUpdates = { ...cardNamesCatalog, notAKey: true };
+    const validator = new CatalogValidator(mockKeyUpdates);
+    expect(validator.validKeys).toBe(false);
+  });
+
+  test("total_values matches data length", async () => {
+    const cardNamesCatalog = await cardNamesRequest;
+    const validator = new CatalogValidator(cardNamesCatalog);
+    const dataLength = validator.validDataLength;
+    expect(dataLength).toBe(true);
+  });
+});

src/__tests__/objects/Catalog/Catalog.test.ts

@@ -1 +1,2 @@
 export * from "./objects";
+export * from "./validators";

src/index.ts

@@ -0,0 +1,24 @@
+/**
+ * Represents the most basic needs for a Validator class.
+ * @abstract
+ * @class BaseValidator
+ */
+export default abstract class BaseValidator<T extends Record<string, unknown> = Record<string, unknown>> {
+  /** The object passed to the Validator */
+  object: T;
+  /** A list of keys we expect to exist in a given object. */
+  abstract expectedKeys: string[];
+
+  /**
+   * @constructor
+   * @param {object} object The object to test against.
+   */
+  constructor(object: T) {
+    this.object = object;
+  }
+
+  /** The keys of the object */
+  get keys(): Array<keyof typeof this.object> {
+    return Object.keys(this.object);
+  }
+}

src/validators/BaseValidator.ts

@@ -0,0 +1 @@
+export { default as BaseValidator } from "./BaseValidator";

src/validators/index.ts

@@ -0,0 +1,65 @@
+import { ScryfallCatalog } from "src/objects";
+import { BaseValidator } from "src/validators";
+
+/**
+ * CatalogValidator
+ *
+ *  @extends BaseValidator
+ */
+export default class CatalogValidator extends BaseValidator {
+  expectedKeys: string[] = <Array<keyof ScryfallCatalog>>["object", "uri", "total_values", "data"];
+
+  /**
+   * @static
+   * @param {object} obj An object to check
+   * @returns {boolean} true if the object passes all expected checks
+   */
+  static isCatalogObject(obj: Record<string, unknown>): obj is ScryfallCatalog {
+    const validator = new CatalogValidator(obj);
+
+    return validator.validKeys && validator.validKeyType && validator.validDataType;
+  }
+
+  /**
+   * true if the object matches all expected keys
+   * @type {boolean}
+   */
+  get validKeys(): boolean {
+    return this.keys.every((val) => this.expectedKeys.includes(val));
+  }
+
+  /**
+   * true if the all keys are of the expected type
+   * @type {boolean}
+   * */
+  get validKeyType(): boolean {
+    const objectIsCatalog = this.object.object === "catalog";
+    const uriIsString = typeof this.object.uri === "string";
+    const totalValsIsNumber = typeof this.object.total_values === "number";
+    const dataIsStringArray = this.validDataType;
+    return objectIsCatalog && uriIsString && totalValsIsNumber && dataIsStringArray;
+  }
+
+  /**
+   * true if the 'data' field is the correct type
+   * @type {boolean}
+   */
+  get validDataType(): boolean {
+    if (!Array.isArray(this.object.data)) throw new Error("data is not an array");
+
+    const isJSObject = typeof this.object.data === "object";
+    const isArray = Array.isArray(this.object.data);
+    const onlyHasStrings = this.object.data.every((val) => typeof val === "string");
+    return isJSObject && isArray && onlyHasStrings;
+  }
+
+  /**
+   * true if the 'data' field length matches the 'total_values' number
+   * @type {boolean}
+   */
+  get validDataLength(): boolean {
+    if (!Array.isArray(this.object.data)) throw new Error("data is not an array");
+
+    return this.object.data.length === this.object.total_values;
+  }
+}