How to make Echo support media type `text/xml` ?

[qianguozheng]

Description

When I using echo to build my own web server, I find that when the client request with none standard http Content-Type, echo will just return 415 media type unsupported,

For the packet captured as below, the Content-Type is text/xml.

POST /wx?signature=0af0cbc713df074c3fefa4a9916c9b7fdf28194c&timestamp=1488192434&nonce=1149750594&openid=oQwuZwwzZW7uoOvKM70E8A3Z4xKM HTTP/1.1
User-Agent: Mozilla/4.0
Accept: */*
Host: hiweeds.net
Pragma: no-cache
Content-Length: 280
Content-Type: text/xml

<xml><ToUserName><![CDATA[gh_caef70508bdb]]></ToUserName>
<FromUserName><![CDATA[oQwuZwwzZW7uoOvKM70E8A3Z4xKM]]></FromUserName>
<CreateTime>1488192434</CreateTime>
<MsgType><![CDATA[event]]></MsgType>
<Event><![CDATA[unsubscribe]]></Event>
<EventKey><![CDATA[]]></EventKey>
</xml>HTTP/1.1 415 Unsupported Media Type
Content-Type: application/json; charset=UTF-8
Date: Mon, 27 Feb 2017 10:47:14 GMT
Content-Length: 36

{"message":"Unsupported Media Type"}

Checklist

• [ * ] Dependencies installed
• [ * ] No typos
• [ * ] Searched existing issues and docs

Expected behaviour

We want to support processing such request.

Actual behaviour

Echo just block it before I processing it.

Steps to reproduce

just use curl command to request echo based web server. with content-type as text/xml

Working code to debug

Normal Echo based web server.

package main

func main() {
}

Version/commit

Latest

[vishr]

It seems like you are using Contex#Bind to decode an xml payload, if that is the case, we only check for application/xml. Not sure if we would like to include text/xml?

@Anon-Penguin @ansel1

http://stackoverflow.com/questions/4832357/whats-the-difference-between-text-xml-vs-application-xml-for-webservice-respons

[qianguozheng]

@vishr could we make it support adding middleware to make it support any media type user want to use ?

[ansel1]

Wouldn't using a custom binder accomplish this? Perhaps by wrapping the DefaultBinder?

[vishr]

As @ansel1 stated, for any custom content type you should use set a custom binder which wraps the default binder, however this is just an alias for application/xml so I have included it in default binder. Please verify.

I will update document on how to use customer binder (if it's not there ;)

[qianguozheng]

Thanks, I would like to learn how to use customer binder.