Feature #298: Views Namespace

README.md

@@ -55,7 +55,7 @@ Eta is a lightweight and blazing fast embedded JS templating engine that works i
   - Great error reporting
 - ⚡️ Exports ES Modules as well as UMD
 - 📝 Easy template syntax
-
+- Namespaces for easy tempalte include
 ## Get Started
 
 _For more thorough documentation, visit [https://eta.js.org](https://eta.js.org)_
@@ -84,8 +84,33 @@ const eta = new Eta({ views: path.join(__dirname, "templates") });
 
 const res = eta.render("./simple", { name: "Ben" });
 console.log(res); // Hi Ben!
+
+
+
 ```
+Using namespaces
+```ts
+  import { Eta } from "eta";
+  const eta = new Eta({ namespaces: {
+    '@myroot' : path.join(__dirname, "templates"),
+    '@includes' : path.join(__dirname, "templates",'includes'),
+    '@components' : path.join(__dirname, "templates",'components')
+  } });
+
+  const res = eta.render("@myroot/sample", { name: "Ben" });
+  console.log(res); // Hi Ben!
 
+```
+Namespace usage within template
+
+```html
+<% include('@includes/header') %>
+<div>
+  <h1>Welcome to the Index Page</h1>
+  <p>Here's a widget:</p>
+  <% include('@components/widget') %>
+</div>
+```
 ## FAQs
 
 <details>

src/config.ts

@@ -78,6 +78,29 @@ export interface EtaConfig {
 
   /** Control template file extension defaults. Default `.eta` */
   defaultExtension?: string;
+
+
+  /**
+  *  Give namespaces to view paths with `@prefix`.
+  *  
+  *  Example:
+  *  ```typescript
+  *  const eta = new Eta({ 
+  *     namespaces: {
+  *        '@includes': path.join(__dirname, 'src', 'views', 'includes')
+  *     }
+  *  });
+  *  
+  *  // Usage in code:
+  *  eta.render('@includes/header', { title: 'Home' });
+  *  ```
+  *  
+  *  Within a template, you can use the namespace like this:
+  *  ```html
+  *  <% include('@includes/header') %>
+  *  ```
+  */
+  namespaces?: { [key: string]: string };
 }
 
 /* END TYPES */

src/file-handling.ts

@@ -11,6 +11,9 @@ import type { Options } from "./config.ts";
 
 export function readFile(this: EtaCore, path: string): string {
   let res = "";
+  if(path.startsWith('@') && this.config.namespaces){
+    path = resolveNamespace.call(this,path) ?? path;
+  }
 
   try {
     res = fs.readFileSync(path, "utf8");
@@ -26,23 +29,58 @@ export function readFile(this: EtaCore, path: string): string {
   return res;
 }
 
+/**
+ *  Funtion resolves namespace path provided on namespaces in config
+ */
+function resolveNamespace(this: EtaCore,templatePath : string)  : string | null{
+  const defaultExtension = this.config.defaultExtension === undefined
+    ? ".eta"
+    : this.config.defaultExtension;
+  if(this.config.namespaces){
+    const entries = Object.keys(this.config.namespaces);
+    const namespace = entries.find(namespaceKey => {
+      return templatePath.startsWith(namespaceKey);
+    });
+    if(namespace){
+      templatePath = templatePath.replace(namespace,this.config.namespaces[namespace]);
+      templatePath += path.extname(templatePath) ? "" : defaultExtension;
+       return templatePath;
+    }
+  }
+  return null;
+}
+
+
+
+
+
 export function resolvePath(
   this: EtaCore,
   templatePath: string,
   options?: Partial<Options>,
 ): string {
   let resolvedFilePath = "";
+  const defaultExtension = this.config.defaultExtension === undefined
+    ? ".eta"
+    : this.config.defaultExtension;
+    const baseFilePath = options && options.filepath;
+
+
+    // Check if tempalte path has a namespace constant at the begining
+  if(templatePath.startsWith('@') && this.config.namespaces){
+    resolvedFilePath =  resolveNamespace.call(this,templatePath) ?? "";
+    return resolvedFilePath;
+  }
+
 
   const views = this.config.views;
+
 
   if (!views) {
     throw new EtaFileResolutionError("Views directory is not defined");
   }
 
-  const baseFilePath = options && options.filepath;
-  const defaultExtension = this.config.defaultExtension === undefined
-    ? ".eta"
-    : this.config.defaultExtension;
+
 
   // how we index cached template paths
   const cacheIndex = JSON.stringify({

src/render.ts

@@ -15,7 +15,7 @@ function handleCache(
     ? this.templatesAsync
     : this.templatesSync;
 
-  if (this.resolvePath && this.readFile && !template.startsWith("@")) {
+  if (this.resolvePath && this.readFile) {
     const templatePath = options.filepath as string;
 
     const cachedTemplate = templateStore.get(templatePath);
@@ -25,6 +25,7 @@ function handleCache(
     } else {
       const templateString = this.readFile(templatePath);
 
+
       const templateFn = this.compile(templateString, options);
 
       if (this.config.cache) templateStore.define(templatePath, templateFn);
@@ -54,7 +55,7 @@ export function render<T extends object>(
   const options = { ...meta, async: false };
 
   if (typeof template === "string") {
-    if (this.resolvePath && this.readFile && !template.startsWith("@")) {
+    if (this.resolvePath && this.readFile) {
       options.filepath = this.resolvePath(template, options);
     }
 
@@ -78,7 +79,7 @@ export function renderAsync<T extends object>(
   const options = { ...meta, async: true };
 
   if (typeof template === "string") {
-    if (this.resolvePath && this.readFile && !template.startsWith("@")) {
+    if (this.resolvePath && this.readFile) {
       options.filepath = this.resolvePath(template, options);
     }