Language statistics bar for repositories (#8037)

* Implementation for calculating language statistics

Impement saving code language statistics to database

Implement rendering langauge stats

Add primary laguage to show in repository list

Implement repository stats indexer queue

Add indexer test

Refactor to use queue module

* Do not timeout for queues

vendor/github.com/src-d/enry/v2/utils.go

@@ -0,0 +1,84 @@
+package enry
+
+import (
+	"bytes"
+	"path/filepath"
+	"strings"
+
+	"github.com/src-d/enry/v2/data"
+)
+
+const binSniffLen = 8000
+
+var configurationLanguages = map[string]bool{
+	"XML": true, "JSON": true, "TOML": true, "YAML": true, "INI": true, "SQL": true,
+}
+
+// IsConfiguration tells if filename is in one of the configuration languages.
+func IsConfiguration(path string) bool {
+	language, _ := GetLanguageByExtension(path)
+	_, is := configurationLanguages[language]
+	return is
+}
+
+// IsImage tells if a given file is an image (PNG, JPEG or GIF format).
+func IsImage(path string) bool {
+	extension := filepath.Ext(path)
+	if extension == ".png" || extension == ".jpg" || extension == ".jpeg" || extension == ".gif" {
+		return true
+	}
+
+	return false
+}
+
+// GetMIMEType returns a MIME type of a given file based on its languages.
+func GetMIMEType(path string, language string) string {
+	if mime, ok := data.LanguagesMime[language]; ok {
+		return mime
+	}
+
+	if IsImage(path) {
+		return "image/" + filepath.Ext(path)[1:]
+	}
+
+	return "text/plain"
+}
+
+// IsDocumentation returns whether or not path is a documentation path.
+func IsDocumentation(path string) bool {
+	return data.DocumentationMatchers.Match(path)
+}
+
+// IsDotFile returns whether or not path has dot as a prefix.
+func IsDotFile(path string) bool {
+	base := filepath.Base(filepath.Clean(path))
+	return strings.HasPrefix(base, ".") && base != "."
+}
+
+// IsVendor returns whether or not path is a vendor path.
+func IsVendor(path string) bool {
+	return data.VendorMatchers.Match(path)
+}
+
+// IsBinary detects if data is a binary value based on:
+// http://git.kernel.org/cgit/git/git.git/tree/xdiff-interface.c?id=HEAD#n198
+func IsBinary(data []byte) bool {
+	if len(data) > binSniffLen {
+		data = data[:binSniffLen]
+	}
+
+	if bytes.IndexByte(data, byte(0)) == -1 {
+		return false
+	}
+
+	return true
+}
+
+// GetColor returns a HTML color code of a given language.
+func GetColor(language string) string {
+	if color, ok := data.LanguagesColor[language]; ok {
+		return color
+	}
+
+	return "#cccccc"
+}