astroboy
Version:
Astroboy（阿童木）is a Nodejs SFB(Separation of Front and Back ends) framework, built on koa2.
69 lines • 2.29 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
const assert = require("assert");
const path = require("path");
const fs = require("fs");
class ViewManager extends Map {
/**
* @param {Application} app - application instance
*/
constructor(app) {
super();
this.config = app.config.view;
if (typeof this.config.root === 'string') {
this.config.root = [this.config.root];
}
this.extMap = new Map();
this.fileMap = new Map();
for (const ext of Object.keys(this.config.mapping)) {
this.extMap.set(ext, this.config.mapping[ext]);
}
}
/**
* This method can register view engine.
*
* You can define a view engine class contains two method, `render` and `renderString`
*
* ```js
* class View {
* render() {}
* renderString() {}
* }
* ```
* @param {String} name - the name of view engine
* @param {Object} viewEngine - the class of view engine
*/
use(name, viewEngine) {
assert(name, 'name is required');
assert(!this.has(name), `${name} has been registered`);
assert(viewEngine, 'viewEngine is required');
assert(viewEngine.prototype.render, 'viewEngine should implement `render` method');
assert(viewEngine.prototype.renderString, 'viewEngine should implement `renderString` method');
this.set(name, viewEngine);
}
async resolve(name) {
const config = this.config;
// check cache
let filename = this.fileMap.get(name);
if (config.cache && filename) {
return filename;
}
// try find it with default extension
filename = this.resolvePath([name, name + config.defaultExtension], config.root);
// set cache
this.fileMap.set(name, filename);
return filename;
}
resolvePath(names, root) {
for (const name of names) {
for (const dir of root) {
const filename = path.resolve(dir, name);
if (fs.existsSync(filename)) {
return filename;
}
}
}
}
}
exports.ViewManager = ViewManager;
//# sourceMappingURL=ViewManager.js.map