Change signature for JSON validation to T|T[]

src/index.ts

@@ -17,9 +17,9 @@ export interface TransformValdiationOptions {
  * @param {ClassType<T>} classType The Class to parse and convert JSON to
  * @param {string} jsonString The string containing JSON
  * @param {TransformValdiationOptions} [options] Optional options object for class-validator and class-transformer
- * @returns {Promise<T>} Promise of object of given class T
+ * @returns {Promise<T|T[]>} Promise of object of given class T or array of objects given class T
  */
-export function transformAndValidate<T extends object>(classType: ClassType<T>, jsonString: string, options?: TransformValdiationOptions): Promise<T>;
+export function transformAndValidate<T extends object>(classType: ClassType<T>, jsonString: string, options?: TransformValdiationOptions): Promise<T|T[]>;
 /**
  * Asynchronously converts array of plain objects to array of class (constructor) objects.
  * Reject the promise if any of the objects in array doesn't pass validation.
@@ -71,9 +71,9 @@ export function transformAndValidate<T extends object>(classType: ClassType<T>,
  * @param {ClassType<T>} classType The Class to parse and convert JSON to
  * @param {string} jsonString The string containing JSON
  * @param {TransformValdiationOptions} [options] Optional options object for class-validator and class-transformer
- * @returns {T} Object of given class T
+ * @returns {T|T[]} Object of given class T or array of objects given class T
  */
-export function transformAndValidateSync<T extends object>(classType: ClassType<T>, jsonString: string, options?: TransformValdiationOptions): T;
+export function transformAndValidateSync<T extends object>(classType: ClassType<T>, jsonString: string, options?: TransformValdiationOptions): T|T[];
 /**
  * Synchronously converts array of plain objects to array of class (constructor) objects.
  * Throws error if any of the objects in array doesn't pass validation.

src/tests/index.ts

@@ -32,16 +32,28 @@ describe("transformAndValidate()", () => {
         expect(transformedUser.greet()).to.equals("Greeting");
     });
 
-    it("should successfully transform and validate User JSON", async () => {
+    it("should successfully transform and validate JSON with User object", async () => {
         const userJson: string = JSON.stringify(user);
 
-        const transformedUser: User = await transformAndValidate(User, userJson);
+        const transformedUser = await transformAndValidate(User, userJson) as User;
 
         expect(transformedUser).to.exist;
         expect(transformedUser.email).to.equals("test@test.com");
         expect(transformedUser.greet()).to.equals("Greeting");
     });
 
+    it("should successfully transform and validate JSON with array of Users", async () => {
+        const userJson: string = JSON.stringify([user]);
+
+        const transformedUsers = await transformAndValidate(User, userJson) as User[];
+
+        expect(transformedUsers).to.exist;
+        expect(transformedUsers).to.be.an.instanceof(Array);
+        expect(transformedUsers).to.have.lengthOf(1);
+        expect(transformedUsers[0].email).to.equals("test@test.com");
+        expect(transformedUsers[0].greet()).to.equals("Greeting");
+    });
+
     it("should successfully transform and validate array of User objects", async () => {
         const users = [
             user,
@@ -161,16 +173,28 @@ describe("transformAndValidateSync()", () => {
         expect(transformedUser.greet()).to.equals("Greeting");
     });
 
-    it("should successfully transform and validate User JSON", async () => {
+    it("should successfully transform and validate JSON with User object", async () => {
         const userJson: string = JSON.stringify(user);
 
-        const transformedUser: User = transformAndValidateSync(User, userJson);
+        const transformedUser = transformAndValidateSync(User, userJson) as User;
 
         expect(transformedUser).to.exist;
         expect(transformedUser.email).to.equals("test@test.com");
         expect(transformedUser.greet()).to.equals("Greeting");
     });
 
+    it("should successfully transform and validate JSON with array of Users", async () => {
+        const userJson: string = JSON.stringify([user]);
+
+        const transformedUsers = transformAndValidateSync(User, userJson) as User[];
+
+        expect(transformedUsers).to.exist;
+        expect(transformedUsers).to.be.an.instanceof(Array);
+        expect(transformedUsers).to.have.lengthOf(1);
+        expect(transformedUsers[0].email).to.equals("test@test.com");
+        expect(transformedUsers[0].greet()).to.equals("Greeting");
+    });
+
     it("should successfully transform and validate array of User objects", async () => {
         const users = [
             user,