test: extended test cases with the utility methods

utils/download_test.go

@@ -0,0 +1,38 @@
+package utils
+
+import (
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestUtils_ShouldDownloadImage(t *testing.T) {
+	f, err := DownloadImage("https://raw.githubusercontent.com/esimov/caire/master/testdata/sample.jpg")
+	if err != nil {
+		t.Fatalf("could't download test file: %v", err)
+	}
+
+	if !strings.Contains(f.Name(), "tmp") {
+		t.Errorf("The downloaded image should have been saved in a temporary folder")
+	}
+}
+
+func TestUtils_ShouldBeValidUrl(t *testing.T) {
+	ok := IsValidUrl("https://github.com/esimov/caire/")
+	if !ok {
+		t.Errorf("A valid URL should have been provided")
+	}
+}
+
+func TestUtils_ShouldDetectValidFileType(t *testing.T) {
+	sampleImg := filepath.Join("../testdata", "sample.jpg")
+
+	ftype, err := DetectFileContentType(sampleImg)
+	if err != nil {
+		t.Fatalf("could not detect content type: %v", err)
+	}
+
+	if !strings.Contains(ftype.(string), "image") {
+		t.Errorf("Content type expected to be of type image, got: %v", ftype)
+	}
+}