Nunjucks：如何绕过自定义扩展的自动景观？

Question

我设法在Nunjucks.js中制作异步自定义扩展，但我仍然有一些未解答的问题。以下是其中之一。

如何配置您的扩展程序以避免其输出。我的代码看起来像那样。

var nunjucks = require('nunjucks');

module.exports = function CustomExtension() {
this.tags = ['docs'];

this.parse = function(parser, nodes, lexer) {


    // parse the args and move after the block end. passing true
    // as the second arg is required if there are no parentheses
    var args = parser.parseSignature(null, true);

    parser.nextToken();


    // parse the content until end block

    var body = parser.parseUntilBlocks('enddocs');

    parser.advanceAfterBlockEnd();

    return new nodes.CallExtensionAsync(this, 'run', args, [body]);
};

this.run = function(context, arguments, body, callback) {


    var id = body();

    somAsyncMagic(id, function(html) {

        callback(null, html);

    });


};

}

顺便提一下，这段代码用在节点中。如果那可能会激起某些人的想法。

谢谢

Answer 1

您可以访问所有内部过滤器，因此答案是cb(null, nunjucks.filters.safe(html));。

var nunjucks = require('nunjucks');

var MyLoader = nunjucks.Loader.extend({
    async: true,
    getSource: function(name, callback) {
        var res = '...';
        callback(err, res);
    }
});

var env = new nunjucks.Environment(new MyLoader(), {autoescape: true}); // !

function CustomExtension(cb) {
    this.tags = ['docs'];

    this.parse = function(parser, nodes, lexer) {
        var tok = parser.nextToken();
        var args = parser.parseSignature(null, true);
        parser.nextToken();
        var body = parser.parseUntilBlocks('enddocs');
        parser.advanceAfterBlockEnd();
        return new nodes.CallExtensionAsync(this, 'run', args, [body], cb);
    };

    this.run = function(context, args, body, cb) {
        var res = env.filters.safe(args + ':' + body()); // prevent escape
        cb(null, res);
    };
}    
env.addExtension('CustomExtension', new CustomExtension());

env.renderString('{% docs "<TEST>" %}"OK"{% enddocs %}', console.log);