egg如何添加nunjuck模板自定义过滤器？

Question

Nunjuck官网文档提供演示代码如下，没能生效，演示代码如下。

var nunjucks = require('nunjucks');
var env = new nunjucks.Environment();
 
env.addFilter('shorten', function(str, count) {
    return str.slice(0, count || 5);
});

添加了loader也没用，代码如下：

var nunjucks = require('nunjucks');
var env = new nunjucks.Environment(new nunjucks.FileSystemLoader('app/view'));

//app.js代码
class AppBootHook {
    constructor(app) {
        this.app = app;
    }

    configWillLoad() {
        env.addFilter('shorten', function(str, count) {
            return str.slice(0, count || 5);
        });
    }
}

Answer 1

可以参考 egg-view-nunjucks 文档：https://github.com/eggjs/egg-view-nunjucks?tab=readme-ov-file#filter