added fix for signed url issue 25

Author: KhushbooMer

imagekit-sdk/build.gradle

@@ -4,7 +4,7 @@ plugins {
 }
 
 group 'io.imagekit.sdk'
-version '2.0.0'
+version '2.0.1'
 
 sourceCompatibility = 1.8
 

imagekit-sdk/src/main/java/io/imagekit/sdk/constants/Version.java

@@ -1,5 +1,5 @@
 package io.imagekit.sdk.constants;
 
 public class Version {
-    public static final String VERSION_CODE="java-2.0.0";
+    public static final String VERSION_CODE="java-2.0.1";
 }

imagekit-sdk/src/main/java/io/imagekit/sdk/tasks/UrlGen.java

@@ -124,7 +124,7 @@ private static String buildFullUrl(String src, Map<String, String> queryParamete
 			List<Map<String, String>> transformation, String transformationPosition, boolean signed, long expireSeconds,
 			String privateKey, String urlEndpoint) {
 		StringBuilder tr = new StringBuilder("");
-		if (transformation.size() > 0) {
+		if (transformation != null && transformation.size() > 0) {
 			tr.append("tr=");
 			for (Map<String, String> map : transformation) {
 				Set<Map.Entry<String, String>> entries = map.entrySet();
@@ -193,10 +193,10 @@ private static void sign(String urlEndpoint, long expireSeconds, String privateK
 			expiryTimestamp = ((Calendar.getInstance().getTimeInMillis() / 1000) + expireSeconds);
 		}
 		String signature = signUrl(privateKey, tmpUri.toString(), urlEndpoint, expiryTimestamp);
-		queryMaker.put("ik-s=" + signature);
 		if (expiryTimestamp > 0 && expiryTimestamp != DEFAULT_TIMESTAMP) {
 			queryMaker.put("ik-t=" + expiryTimestamp);
 		}
+		queryMaker.put("ik-s=" + signature);
 	}
 
 	public static String signUrl(String privateKey, String url, String urlEndpoint, long expiryTimestamp) {

imagekit-sdk/src/test/java/io/imagekit/sdk/GetUrlTest.java

@@ -20,7 +20,7 @@
 import static org.junit.Assert.assertTrue;
 
 public class GetUrlTest {
-	private static final Pattern IMAGEKIT_SIGNED_URL_PATTERN = Pattern.compile("(https://.*)\\?ik-s=(.*)&ik-t=(.*)");
+	private static final Pattern IMAGEKIT_SIGNED_URL_PATTERN = Pattern.compile("(https://.*)\\?ik-t=(.*)&ik-s=(.*)");
 	private ImageKit SUT;
 
 	@Before
@@ -460,7 +460,6 @@ public void getUrl_with_signature() {
 	public void getUrl_with_signature_src_noTransform() {
 		Map<String, Object> options = new HashMap<>();
 		options.put("src", "https://ik.imagekit.io/your_imagekit_id/endpoint/default-image.jpg");
-		options.put("transformation", Collections.emptyList());
 		options.put("signed", true);
 		options.put("expireSeconds", 1000);