crypto = require('crypto').webcrypto
var subtlecrypto = crypto.subtle;

参数:
    ipv4为点分十进制的ipv4地址，比如'192.168.2.100'
    cidrs为CIDR地址列表，比如['192.168.1.1/32','192.168.2.1/24']
 
使用示例:
    if (baidu_utils.ipInCidr('192.168.2.100', ['192.168.1.1/32','192.168.2.1/24'])) {
        r.return(403);
    }

'1234'.toBytes().toString('base64');
'1234'.toBytes().toString('base64url');
require('crypto').createHash('sha1').update('A').update('B').digest('base64');
require('crypto').createHmac('sha1', 'key').update('A').update('B').digest('base64url');

String.bytesFrom('MTIzNA==', 'base64');
String.bytesFrom('MTIzNA', 'base64url');

r.headersOut['Content-Disposition']='attachment;filename=' + '\"' + r.args['filename'] + '\"';

r.headersOut['Access-Control-Allow-Origin']=r.headersIn['Origin'];

r.return(302, '/a');

if (baidu_utils.ipInCidr(r.remoteAddress, ['192.168.1.1/32','192.168.2.1/24'])) { r.return(403); }

var refers = ['http://*.baidu.com.cn/*','http://*.baidu.com/*'];
var i = 0;
for (; i < refers.length; i += 1) {
    if (baidu_utils.matchWildcard(r.headersIn['referer'], refers[i])) {
        r.return(403);
        return;
    }
}

var uas = ['curl','AppleWebKit'];
var i = 0;
var ua = r.headersIn['User-Agent'];
for (; i < uas.length; i += 1) {
    if (ua.includes(uas[i])) {
        r.return(403);
        return;
    }
}

r.variables['limit_rate'] = '1k';

var part = r.uri.substr(1).split('/');
if (part.length < 3) {
    r.return(403);
    return;
}
 
var date_in_uri = part[0];
var d = new Date('');
d.setFullYear(date_in_uri.substring(0, 4));
d.setMonth(date_in_uri.substring(4, 6) - 1); //the month (0-11) in the specified date
d.setDate(date_in_uri.substring(6, 8));
d.setHours(date_in_uri.substring(8, 10));
d.setMinutes(date_in_uri.substring(10));
var time = d.getTime();
var timeout = 1000000000000; // not overdue
if (time + timeout < Date.now()) {
    r.return(403);
    return;
}
 
var md5_in_uri = part.splice(1,1)[0];
var md5_str = 'bdcloud666' + part.join('/');
var md5 = require('crypto').createHash('md5').update(md5_str).digest('hex');
if (md5_in_uri != md5) {
    r.return(403);
    return;
}

r.uri = '/test';

r.args['test1'] = 'test';
if (r.args['test1'] == 'test') { /* use first one if duplicate */
    delete r.args['test2'];
    delete r.args['test']; /* remove all duplicate arg */
}
 
r.args['gy'] = 'test';  /* remove all duplicate arg, add a new one */
r.variables['args'] = 'test=test'; /* set entire args directly */

var xff = r.headersIn['X-Forwarded-For'] + ', ';
r.headersIn['X-Forwarded-For'] = xff.substring(0, xff.length - 2);

function done() {
    r.headersOut['dup'] = 'dup';
}
r.respHeader(done);

if (r.args['a']) {
    r.args['version'] = 'new';
}
else if (r.args['b']) {
    r.args['version'] = 'old';
}

function done() {
    if (r.status == 404) {
        r.status = 302;
        r.headersOut['Location'] = 'http://www.baidu.com/test';
    }
}
 
r.respHeader(done);

function myFunc(item, index) {
    console.log(item);
    // action
}
r.rawHeadersIn.forEach(myFunc);

ngx.fetch('https://www.baidu.com/auth')
.then(function(response) {
    if (!response.ok) {
        return r.return(403, 'forbidden');
    }
})
.catch(e => console.log(e.message));

function pr(x) {
    return new Promise(resolve => {resolve(x)});
}
 
async function add(x) {
    const a = await pr(x);
    throw a + 1;
    const b = await pr(x + 10);
    return a + b;
}
 
add(50).then(v => {console.log(v - 1)}).catch(v => console.log(v));

if (typeof crypto == 'undefined') {
    crypto = require('crypto').webcrypto;
}

let dkey = await crypto.subtle.importKey('raw', params.key,
                                   {name: params.name},
                                   false, ['decrypt']);
 
let ekey = await crypto.subtle.importKey('raw', params.key,
                                   {name: params.name},
                                   false, ['encrypt']);
 
let enc = await crypto.subtle.encrypt(params, ekey, params.data);
let plaintext = await crypto.subtle.decrypt(params, dkey, enc);
plaintext = Buffer.from(plaintext);