Add query parameters serialization(#29)

src/index.js

@@ -63,6 +63,32 @@ export default (function create(defaults) {
 		return (url, data, config) => redaxios(url, Object.assign({ method, data }, config));
 	}
 
+	/**
+	 * Builds request url based on query string parameters
+	 * @private
+	 * @param {string} url
+	 * @param {object|URLSearchParams} [params]
+	 * @param {function} [serializer]
+	 * @returns {string}
+	 */
+	function buildUrl(url, params, serializer) {
+		if (!params) {
+			return url;
+		}
+
+		let serializedParams;
+		if (serializer) {
+			serializedParams = serializer(params);
+		} else if (params instanceof URLSearchParams) {
+			serializedParams = params.toString();
+		} else {
+			serializedParams = (new URLSearchParams(params)).toString();
+		}
+
+		const divider = url.indexOf('?') === -1 ? '?' : '&';
+		return url + divider + serializedParams;
+	}
+
 	/**
 	 * @public
 	 * @type {((config?: Options) => Promise<Response>) | ((url: string, config?: Options) => Promise<Response>)}
@@ -133,6 +159,7 @@ export default (function create(defaults) {
 		}
 		const options = deepMerge(defaults, config || {});
 		let data = options.data;
+		url = buildUrl(url, options.params, options.paramsSerializer);
 
 		if (options.transformRequest) {
 			for (let i = 0; i < options.transformRequest.length; i++) {
@@ -142,7 +169,7 @@ export default (function create(defaults) {
 				}
 			}
 		}
-		
+
 		const fetchFunc = options.fetch || fetch;
 		const customHeaders = {};
 

test/index.test.js

@@ -83,4 +83,34 @@ describe('redaxios', () => {
 		expect(res.status).toEqual(200);
 		expect(JSON.parse(res.data)).toEqual({ hello: 'world' });
 	});
+
+	it('should support params and paramsSerializer options', async () => {
+		const oldFetch = window.fetch;
+		window.fetch = jasmine.createSpy('fetch').and.returnValue(Promise.resolve());
+
+		axios.get('/foo');
+		expect(window.fetch).toHaveBeenCalledTimes(1);
+		expect(window.fetch).toHaveBeenCalledWith('/foo', jasmine.any(Object));
+
+		let params = { a: 1, b: true };
+		axios.get('/foo', { params });
+		expect(window.fetch).toHaveBeenCalledTimes(2);
+		expect(window.fetch).toHaveBeenCalledWith('/foo?a=1&b=true', jasmine.any(Object));
+
+		axios.get('/foo?c=42', { params });
+		expect(window.fetch).toHaveBeenCalledTimes(3);
+		expect(window.fetch).toHaveBeenCalledWith('/foo?c=42&a=1&b=true', jasmine.any(Object));
+
+		params = new URLSearchParams({ d: 'test' });
+		axios.get('/foo', { params });
+		expect(window.fetch).toHaveBeenCalledTimes(4);
+		expect(window.fetch).toHaveBeenCalledWith('/foo?d=test', jasmine.any(Object));
+
+		const paramsSerializer = params => 'e=iamthelaw';
+		axios.get('/foo', { params, paramsSerializer });
+		expect(window.fetch).toHaveBeenCalledTimes(5);
+		expect(window.fetch).toHaveBeenCalledWith('/foo?e=iamthelaw', jasmine.any(Object));
+
+		window.fetch = oldFetch;
+	});
 });