use mime package, update tests

pkg/routing/content_types.go

@@ -3,17 +3,16 @@ package routing
 
 import (
 	"errors"
+	"mime"
 	"path/filepath"
 	"strings"
 )
 
-// getContentType returns the http header safe content-type attribute for the
-// requested path. If the requested path is not formatted correctly with an extension
+// getContentType returns the http header safe Content-Type for the requested
+// path. If the requested path is not formatted correctly with an extension
 // then the function will return the zero-value for a string and an error.
-// BUG(george-e-shaw-iv) Cannot handle interpreted files such as .php files
-// BUG(george-e-shaw-iv) Does not cover the bulk of encountered content types on the web
 func GetContentType(path string) (string, error) {
-	var contentType string
+	var ct string
 
 	path = filepath.Base(path)
 	ext := filepath.Ext(path)
@@ -23,22 +22,11 @@ func GetContentType(path string) (string, error) {
 		return "", errors.New("Invalid file path")
 	}
 
-	switch ext {
-	case ".html":
-		contentType = "text/html"
-	case ".css":
-		contentType = "text/css"
-	case ".js":
-		contentType = "text/javascript"
-	case ".png":
-		contentType = "image/png"
-	case ".jpg":
-		fallthrough
-	case ".jpeg":
-		contentType = "image/jpeg"
-	default:
-		contentType = "text/plain"
+	ct = mime.TypeByExtension(ext)
+
+	if ct == "" {
+		return "", errors.New("Could not get content type")
 	}
 
-	return contentType, nil
+	return ct, nil
 }

pkg/routing/content_types_test.go

@@ -7,29 +7,28 @@ import (
 func TestContentType(t *testing.T) {
 	cases := []struct {
 		input string
-		mime  string
 		ok    bool
 	}{
-		{"/path/to/index.html", "text/html", true},
-		{"somepath/file.css", "text/css", true},
-		{"test.js", "text/javascript", true},
-		{"asdf.png", "image/png", true},
-		{"asdfpng", "", false},
-		{"/something.jpg", "image/jpeg", true},
-		{"/something.jpeg", "image/jpeg", true},
-		{"this/should/fail/.png", "", false},
+		{"/path/to/index.html", true},
+		{"somepath/file.css", true},
+		{"test.js", true},
+		{"./relative/asdf.png", true},
+		{"/something.jpg", true},
+		{"/something.jpeg", true},
+		{"doc.pdf", true},
+		{"this/should/fail/.png", false},
+		{"php/doesnt/have/a/contenttype.php", false},
+		{".pdf", false},
+		{"asdfpng", false},
 	}
 
 	for _, tc := range cases {
 		mime, err := GetContentType(tc.input)
 		if err != nil && tc.ok == true {
-			t.Fatalf("\nGetContentType(%s): Got an error, expected OK.", tc.input)
+			t.Fatalf("\nGetContentType(%s): Expected OK, got error: %s", tc.input, err)
 		}
 		if err == nil && tc.ok == false {
-			t.Fatalf("\nGetContentType(%s): Expected error, got: %s", tc.input, tc.mime)
-		}
-		if mime != tc.mime {
-			t.Fatalf("\nGetContentType(%s):\nWant: %s\nGot: %s", tc.input, tc.mime, mime)
+			t.Fatalf("\nGetContentType(%s): Expected error, got OK: %s", tc.input, mime)
 		}
 	}