<rest:response> - unclear strategy of setting header during serialization
Hello,
I encountered strange behavior during HTTP response.
I need to set custom header Access-Control-Allow-Origin:*.
To do that I am using custom response.
Following code is working and set required header:
declare
%rest:POST("{$json}")
%rest:path("/ping")
function drpg:ping(
$json as xs:string
) as element()* {
<rest:response>
<http:response status="200" message="OK">
<http:header name="Access-Control-Allow-Origin" value="*"/>
<http:header name="Content-Type" value="text/html"/>
</http:response>
</rest:response>,
let $p := json:parse($json)return ($p/json/data/_/_/_)[last()]
};
Response header:
Access-Control-Allow-Origin
*
Content-Length
11
Content-Type
text/html;charset=utf-8
Date
Sat, 14 Jul 2018 09:17:18 GMT
Server
Jetty(9.4.9.v20180320)
I want to return plain text, so when I change return parameter to xs:string* and add data function header from <rest:response> is overwritten.
Response header:
Content-Length
6
Content-Type
application/xml; charset=UTF-8
Date
Sat, 14 Jul 2018 09:26:59 GMT
Server
Jetty(9.4.9.v20180320)
Example code:
declare
%rest:POST("{$json}")
%rest:path("/drpg/ping")
function drpg:ping(
$json as xs:string
) as xs:string* {
<rest:response>
<http:response status="200" message="OK">
<http:header name="Access-Control-Allow-Origin" value="*"/>
<http:header name="Content-Type" value="text/html"/>
</http:response>
</rest:response>,
let $p := json:parse($json)return data(($p/json/data/_/_/_)[last()])
};
Why does header is overwritten ? I think if header is set explicitly it shouldn't be overwritten.
Best Regards Bogdan Bogucki
Hi Bogdan,
If you change the return type of an XQuery function to xs:string, your nodes will be implicitly converted to strings:
declare function local:f() as xs:string {
<a>X</a>
};
(: will result in 'X' :)
local:f()The string conversion of your http:response element yields an empty string, so it does not matter what you specify as attribute values.
If you want to return text/plain, you’ll have to change your content type from text/html to to text/plain:
<http:header name="Content-Type" value="text/plain"/>Best, Christian
Quoted text · Bogdan Bogucki · 155 lines
On Sat, Jul 14, 2018 at 11:30 AM Bogdan Bogucki <bbogucki at hussar.pl> wrote: > Hello, > > > > I encountered strange behavior during HTTP response. > > > > I need to set custom header Access-Control-Allow-Origin:*. > > > > To do that I am using custom response. > > > > Following code is working and set required header: > > > > declare > > %rest:POST("{$json}") > > %rest:path("/ping") > > function drpg:ping( > > $json as xs:string > > ) as element()* { > > > <rest:response> > > <http:response status="200" message="OK"> > > <http:header name="Access-Control-Allow-Origin" value="*"/> > > > <http:header name="Content-Type" value="text/html"/> > > </http:response> > > </rest:response>, > > let $p := json:parse($json) > > return ($p/json/data/_/_/_)[last()] > > }; > > > > Response header: > > Access-Control-Allow-Origin > > * > > > > Content-Length > > 11 > > Content-Type > > text/html;charset=utf-8 > > Date > > Sat, 14 Jul 2018 09:17:18 GMT > > Server > > Jetty(9.4.9.v20180320) > > > > I want to return plain text, so when I change return parameter to > xs:string* and add data function header from <rest:response> is > overwritten. > > > > Response header: > > Content-Length > > 6 > > > > Content-Type > > application/xml; charset=UTF-8 > > Date > > Sat, 14 Jul 2018 09:26:59 GMT > > Server > > Jetty(9.4.9.v20180320) > > > > Example code: > > declare > > %rest:POST("{$json}") > > %rest:path("/drpg/ping") > > function drpg:ping( > > $json as xs:string > > ) as xs:string* { > > <rest:response> > > <http:response status="200" message="OK"> > > <http:header name="Access-Control-Allow-Origin" value="*"/> > > <http:header name="Content-Type" value="text/html"/> > > </http:response> > > </rest:response>, > > let $p := json:parse($json) > > return data(($p/json/data/_/_/_)[last()]) > > }; > > > > Why does header is overwritten ? I think if header is set explicitly it > shouldn't be overwritten. > > > > Best Regards > Bogdan Bogucki > > > > >
Hello,
declare
%rest:POST("{$json}")
%rest:path("/drpg/ping")
function drpg:ping(
$json as xs:string
) as xs:string* {
<rest:response>
<http:response status="200" message="OK">
<http:header name="Access-Control-Allow-Origin" value="*"/>
<http:header name="Content-Type" value="text/plain"/>
</http:response>
</rest:response>,
let $p := json:parse($json)return ($p/json/data/_/_/_)[last()]
};
Element was converted to string but header is overwritten.
Response header:
Content-Length: 6
Content-Type: application/xml; charset=UTF-8
Date: Sat, 14 Jul 2018 11:14:32 GMT
Server: Jetty(9.4.9.v20180320)
How can I set <http:header name="Access-Control-Allow-Origin" value="*"/> ?
Why when return type is element() header is set correctly ?
Access-Control-Allow-Origin : *
Content-Length : 11
Content-Type: text/plain;charset=utf-8
Date: Sat, 14 Jul 2018 11:18:43 GMT
Server: Jetty(9.4.9.v20180320)
Pozdrawiam Bogdan Bogucki
HUSSAR SYSTEMS
NIP: 532-170-12-00
Regon: 142624070
e-mail: <mailto:bbogucki at hussar.pl> bbogucki at hussar.pl tel. kom.: +48 607 409 301 www: <http://www.hussar.pl/> www.hussar.pl
Od: Christian Grün [mailto:christian.gruen at gmail.com] Wysłano: 14 lipca 2018 11:45 Do: Bogdan Bogucki DW: BaseX Temat: Re: [basex-talk] <rest:response> - unclear strategy of setting header during serialization
Hi Bogdan,
If you change the return type of an XQuery function to xs:string, your nodes will be implicitly converted to strings:
declare function local:f() as xs:string {
<a>X</a>};
(: will result in 'X' :)
local:f()The string conversion of your http:response element yields an empty string, so it does not matter what you specify as attribute values.
If you want to return text/plain, you’ll have to change your content type from text/html to to text/plain:
<http:header name="Content-Type" value="text/plain"/>Best, Christian
Quoted text · Bogdan Bogucki · 1 line
On Sat, Jul 14, 2018 at 11:30 AM Bogdan Bogucki <bbogucki at hussar.pl> wrote:
Hello,
I encountered strange behavior during HTTP response.
I need to set custom header Access-Control-Allow-Origin:*.
To do that I am using custom response.
Following code is working and set required header:
declare
%rest:POST("{$json}")
%rest:path("/ping")
function drpg:ping(
$json as xs:string
) as element()* {
<rest:response>
<http:response status="200" message="OK">
<http:header name="Access-Control-Allow-Origin" value="*"/>
<http:header name="Content-Type" value="text/html"/>
</http:response>
</rest:response>,
let $p := json:parse($json)return ($p/json/data/_/_/_)[last()]
};
Response header:
Access-Control-Allow-Origin
*
Content-Length
11
Content-Type
text/html;charset=utf-8
Date
Sat, 14 Jul 2018 09:17:18 GMT
Server
Jetty(9.4.9.v20180320)
I want to return plain text, so when I change return parameter to xs:string* and add data function header from <rest:response> is overwritten.
Response header:
Content-Length
6
Content-Type
application/xml; charset=UTF-8
Date
Sat, 14 Jul 2018 09:26:59 GMT
Server
Jetty(9.4.9.v20180320)
Example code:
declare
%rest:POST("{$json}")
%rest:path("/drpg/ping")
function drpg:ping(
$json as xs:string
) as xs:string* {
<rest:response>
<http:response status="200" message="OK">
<http:header name="Access-Control-Allow-Origin" value="*"/>
<http:header name="Content-Type" value="text/html"/>
</http:response>
</rest:response>,
let $p := json:parse($json)return data(($p/json/data/_/_/_)[last()])
};
Why does header is overwritten ? I think if header is set explicitly it shouldn't be overwritten.
Best Regards Bogdan Bogucki
Quoted text · Bogdan Bogucki · 4 lines
> > If you change the return type of an XQuery function to xs:string, your > nodes will be implicitly converted to strings. >
This is the standard behavior of XQuery and no particular feature of RESTXQ. Play around with the query that I presented in my previous answer.
You need to remove the xs:string* return typeb you can replace it with item()*.
Hello CHristian,
Thank you for help. Understood.
Structure <rest:response> was serialized to empty string. Now It is clear for me why data is lost.
Best Regards Bogdan Bogucki
Od: Christian Grün [mailto:christian.gruen at gmail.com] Wysłano: 14 lipca 2018 13:25 Do: Bogdan Bogucki DW: BaseX Temat: Re: [basex-talk] <rest:response> - unclear strategy of setting header during serialization
If you change the return type of an XQuery function to xs:string, your nodes will be implicitly converted to strings.
This is the standard behavior of XQuery and no particular feature of RESTXQ. Play around with the query that I presented in my previous answer.
You need to remove the xs:string* return typeb you can replace it with item()*.
Written for BaseX 9.0. BaseX may have changed since: please check the current documentation.