[FAB-3055] Enhance the url check on chaincode path

Now we can detect invalid path like '/' or 'http:///'.

Also add new test case.

Fix https://jira.hyperledger.org/browse/FAB-3055.

Change-Id: I28cca3b11ead61563220cc4eda6cb01a0feb8004
Signed-off-by: Baohua Yang <baohyang@cn.ibm.com>

core/chaincode/platforms/golang/platform.go

@@ -60,8 +60,8 @@ func decodeUrl(spec *pb.ChaincodeSpec) (string, error) {
 		urlLocation = spec.ChaincodeId.Path
 	}
 
-	if urlLocation == "" {
-		return "", errors.New("ChaincodeSpec's path/URL cannot be empty")
+	if len(urlLocation) < 2 {
+		return "", errors.New("ChaincodeSpec's path/URL invalid")
 	}
 
 	if strings.LastIndex(urlLocation, "/") == len(urlLocation)-1 {

core/chaincode/platforms/golang/platform_test.go

@@ -88,3 +88,38 @@ func Test_writeGopathSrc(t *testing.T) {
 	//ioutil.WriteFile("/tmp/chaincode_deployment.tar", inputbuf.Bytes(), 0644)
 
 }
+
+func Test_decodeUrl(t *testing.T) {
+	cs := &pb.ChaincodeSpec{
+		ChaincodeId: &pb.ChaincodeID{
+			Name: "Test Chaincode",
+			Path: "http://github.com/hyperledger/fabric/examples/chaincode/go/map",
+		},
+	}
+
+	if _, err := decodeUrl(cs); err != nil {
+		t.Fail()
+		t.Logf("Error to decodeUrl unsuccessfully with valid path: %s, %s", cs.ChaincodeId.Path, err)
+	}
+
+	cs.ChaincodeId.Path = ""
+
+	if _, err := decodeUrl(cs); err == nil {
+		t.Fail()
+		t.Logf("Error to decodeUrl successfully with invalid path: %s", cs.ChaincodeId.Path)
+	}
+
+	cs.ChaincodeId.Path = "/"
+
+	if _, err := decodeUrl(cs); err == nil {
+		t.Fail()
+		t.Logf("Error to decodeUrl successfully with invalid path: %s", cs.ChaincodeId.Path)
+	}
+
+	cs.ChaincodeId.Path = "http:///"
+
+	if _, err := decodeUrl(cs); err == nil {
+		t.Fail()
+		t.Logf("Error to decodeUrl successfully with invalid path: %s", cs.ChaincodeId.Path)
+	}
+}