Taro / JS / H5 / applet: applet solve unified micro-channel payment orders and transfer payments from

This article does not say the specific code path 0-1, I will focus on how to solve a few problems

The main problems encountered paid as follows:

1. Get openid

2. unified under a single, get a pre-order number (I got up, full name prepaid transaction session identifier)

3. invoking payment

4. After payment processing

 

1. Obtain openid very simple, call Taro.login () to get the code, get passed to the back-end openid, this must take back end

2. Unified several issues under orders:

Probably you need so many mandatory parameters:

{
            AppID: '', // AppID 
            mch_id: '',   // merchant ID 
            nonce_str: '', // random string 
            body: '', // Product brief description 
            out_trade_no: '', // merchant system internal order number, the only 
            total_fee: '', // order total, in minutes 
            spbill_create_ip: '', // your ip, you pass to the back-end 
            notify_url: '', // notification address, micro-channel tone, telling you to pay where 
            trade_type: 'JSAPI' ,
            openid: '' 
}

 

 

① random string

② signature

③XML assembly and analysis

 

①

export function randomString(len = 32) {
    const chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';
    const maxPos = chars.length;
    let pwd = '';
    for (let i = 0; i < len; i++) {
        pwd += chars.charAt(Math.floor(Math.random() * maxPos));
    }
    return pwd;
}

 

②

Prepare a parameter as follows

const params = {
    appid: '', 
    Mch_id: '' ,
    nonce_str:randomString(32),
    body: '',
    out_trade_no:  '',
    total_fee: '',
    spbill_create_ip:  '',
    notify_url: '',
    trade_type: 'JSAPI',
    openid: ''
}

 

signature:

const sign = signFunc(params)
        params.sign = sign

Signature function

Export function signFunc (Data) {
     // 1. sort key dictionary 
    const = sortArr Object.keys (Data) .sort ()

    // 2. turn on the key-URL 
    // const = qsString the stringify (sortObj) 
    the let qsString = '' 
    sortArr.map ((T, index) => {
         IF (index === 0 ) {
            qsString = `${t}=${data[t]}`
        } else {
            qsString = `${qsString}&${t}=${data[t]}`
        }
    })

    // 3.拼接string+key
    const stringSignTemp = qsString + `&key=${key}`

    // 4.MD5 signature 
    const Sign = MD5 (stringSignTemp) .toUpperCase ()

    return sign
}

Note that I comment phrase, is called qs of npm library, do not use it to generate the URL parameter key-value pairs, because

 

③