Initial commit.

funcmap/funcmap.go

@@ -0,0 +1,58 @@
+package funcmap
+
+import (
+	"fmt"
+	"html/template"
+	"reflect"
+	"strings"
+
+	"github.com/Masterminds/sprig"
+	"github.com/labstack/gommon/random"
+)
+
+// CacheKey stores a random string used as a cache key for static files
+var CacheKey = random.String(10)
+
+func GetFuncMap() template.FuncMap {
+	// See http://masterminds.github.io/sprig/ for available funcs
+	funcMap := sprig.FuncMap()
+
+	// Provide a list of custom functions
+	f := template.FuncMap{
+		"hasField": HasField,
+		"file":     File,
+		"link":     Link,
+	}
+
+	for k, v := range f {
+		funcMap[k] = v
+	}
+
+	return funcMap
+}
+
+// HasField checks if an interface contains a given field
+func HasField(v interface{}, name string) bool {
+	rv := reflect.ValueOf(v)
+	if rv.Kind() == reflect.Ptr {
+		rv = rv.Elem()
+	}
+	if rv.Kind() != reflect.Struct {
+		return false
+	}
+	return rv.FieldByName(name).IsValid()
+}
+
+// File appends a cache key to a given filepath so it can remain cached until the app is restarted
+func File(filepath string) string {
+	return fmt.Sprintf("%s?v=%s", filepath, CacheKey)
+}
+
+func Link(url, text, currentPath string, classes ...string) template.HTML {
+	if currentPath == url {
+		classes = append(classes, "active")
+	}
+
+	html := fmt.Sprintf(`<a class="%s" href="%s">%s</a>`, strings.Join(classes, " "), url, text)
+	return template.HTML(html)
+}