snake_case

webcontroller/template_manager.go

@@ -0,0 +1,106 @@
+package webcontroller
+
+import (
+	"html/template"
+	"os"
+	"path/filepath"
+	"strconv"
+	"time"
+
+	"github.com/Fornaxian/log"
+)
+
+// TemplateManager parses templates and provides utility functions to the
+// templates' scripting language
+type TemplateManager struct {
+	templates *template.Template
+
+	// Config
+	templateDir         string
+	externalAPIEndpoint string
+	debugModeEnabled    bool
+}
+
+// NewTemplateManager creates a new template manager
+func NewTemplateManager(templateDir, externalAPIEndpoint string, debugMode bool) *TemplateManager {
+	return &TemplateManager{
+		templateDir:         templateDir,
+		externalAPIEndpoint: externalAPIEndpoint,
+		debugModeEnabled:    debugMode,
+	}
+}
+
+// ParseTemplates parses the templates in the template directory which is
+// defined in the config file.
+// If silent is false it will print an info log message for every template found
+func (tm *TemplateManager) ParseTemplates(silent bool) {
+	var templatePaths []string
+
+	filepath.Walk(tm.templateDir, func(path string, f os.FileInfo, err error) error {
+		if f.IsDir() {
+			return nil
+		}
+		templatePaths = append(templatePaths, path)
+		if !silent {
+			log.Info("Template found: %s", path)
+		}
+		return nil
+	})
+
+	tpl := template.New("")
+
+	// Import template functions from funcs.go
+	tpl = tpl.Funcs(tm.funcMap())
+
+	var err error
+	tpl, err = tpl.ParseFiles(templatePaths...)
+	if err != nil {
+		log.Error("Template parsing failed: %v", err)
+	}
+
+	// Swap out the old templates with the new templates, to minimize
+	// modifications to the original variable.
+	tm.templates = tpl
+}
+
+// Get returns the templates, so they can be used to render views
+func (tm *TemplateManager) Get() *template.Template {
+	if tm.debugModeEnabled {
+		tm.ParseTemplates(true)
+	}
+	return tm.templates
+}
+
+func (tm *TemplateManager) funcMap() template.FuncMap {
+	return template.FuncMap{
+		"bgPatternCount": tm.bgPatternCount,
+		"debugMode":      tm.debugMode,
+		"apiUrl":         tm.apiURL,
+		"pageNr":         tm.pageNr,
+		"add":            tm.add,
+		"sub":            tm.sub,
+	}
+}
+
+func (tm *TemplateManager) bgPatternCount() uint8 {
+	return uint8(time.Now().UnixNano() % 17)
+}
+func (tm *TemplateManager) debugMode() bool {
+	return tm.debugModeEnabled
+}
+func (tm *TemplateManager) apiURL() string {
+	return tm.externalAPIEndpoint
+}
+func (tm *TemplateManager) pageNr(s string) (nr int) {
+	// Atoi returns 0 on error, which is fine for page numbers
+	if nr, _ = strconv.Atoi(s); nr < 0 {
+		return 0
+	}
+	return nr
+}
+func (tm *TemplateManager) add(a, b int) int {
+	return a + b
+}
+func (tm *TemplateManager) sub(a, b int) int {
+	return a - b
+}