fix request error when image sending too fast

[System233]

Finally I figured out where wx2.qq.comundefined come from:

puppet-wechat/src/wechaty-bro.js

Lines 332 to 347 in 035e904

	/**
	*
	* Help Functions which Proxy to WXAPP AngularJS Scope & Factory
	* getMsgImg(message.MsgId,'slave')
	* getMsgImg(message.MsgId,'big',message)
	*/
	function getMsgImg (id, type, message) {
	const contentChatScope = WechatyBro.glue.contentChatScope
	if (!contentChatScope) {
	throw new Error('getMsgImg() contentChatScope not found')
	}
	const path = contentChatScope.getMsgImg(id, type, message)
	return window.location.origin + path
	// https://wx.qq.com/?&lang=en_US/cgi-bin/mmwebwx-bin/webwxgetmsgimg?&MsgID=4520385745174034093&skey=%40crypt_f9cec94b_a3aa5c868466d81bc518293eb292926e
	// https://wx.qq.com/cgi-bin/mmwebwx-bin/webwxgetmsgimg?&MsgID=8454987316459381112&skey=%40crypt_f9cec94b_bd210b2224f217afeab8d462af70cf53
	}

https://github.com/wechaty/webwx-app-tracker/blob/a12c78fb8bd7186c0f3bb0e18dd611151e6b8aac/formatted/webwxApp.js#L2100-L2106
some getMsgImg call returned undefined and FileBox requested the url.

If I send images one by one and save them, everything is fine, if I sending images too fast, an error will be occurred and crash the process when exception be passed to wechaty.

Error: getaddrinfo ENOTFOUND wx2.qq.comundefined
    at GetAddrInfoReqWrap.onlookup [as oncomplete] (node:dns:71:26)

It should be fixed in #183, but I made a mistake, I thought $watch will works like Vue watch API, but it's not, the watch handler will be called immediately in first time even though MMStatus doesn't change.

#183 should always fail in my manual tests, but it does work, and it should not happen in #184 tests(I think the error cause by the default value of MMStatus change to 'SENDING' in #183), which is weird.

Other Enhancements

1. I want to increase the priority of file.mediaType to ensure that user behavior is not overwritten
   

   puppet-wechat/src/puppet-wechat.ts

   Line 1245 in 035e904

   const contentType = mime.getType(ext) || file.mediaType || undefined

const contentType = file.mediaType || mime.getType(ext)  || undefined

2. Can we add an error handler to catch exceptions from user listeners to ensure that process dose not crash?

import {WechatyBuilder} from "wechaty"
import {generate} from "qrcode-terminal"
const bot=WechatyBuilder.build({puppet:'wechaty-puppet-wechat'});
bot.on('scan',code=>generate(code,{small:true}));
bot.on('message',()=>{
    throw new Error('crash')
})
bot.start();

[huan]

Please keep the tests/puppeteer-attachment.spec.ts file permission to be 100755 so that it can be executed directly under Linux.

[huan]

Can we add an error handler to catch exceptions from user listeners to ensure that the process does not crash?

If an error on wechaty instance has not been caught then the process will crash.

In order to catch it, we can use:

wechaty.on('error', e => {
  console.error(e)
})

to catch it.

Please let me know if you have more questions, thank you very much.

[huan]

LGTM

Please feel free to help yourself to merge this PR when you believe everything is OK with it, thank you very much!

[System233]

LGTM

Please feel free to help yourself to merge this PR when you believe everything is OK with it, thank you very much!

Thanks, I will.