pp::URLLoader.Open callback returns PP_ERROR_NOACCESS for POST even though the request succeed.

[oh...@beamr.com]

Hi,

I have the following scenario:

Server A with pnacl

When the client browse to server A the pnacl code is doing http POST to server B using pp::URLLoader.Open().

The call succeed but still the Open callback gets error -7 (PP_ERROR_NOACCESS)

Here is the code snippet:

 pp::URLRequestInfo* _req;

 pp::URLLoader* _urlLoader;

// ...

 _req->SetURL(_url);

 _req->SetMethod("POST");

 _req->SetAllowCrossOriginRequests(true);

_urlLoader->Open(*_req, cc);

// the callback gets -7 later.

Can anyone explain to me why I get the -7 result?

Thanks.

[Bill Budge]

It's impossible to say for sure without seeing the response. But PPB_URLLoader follows the CORS standard for cross origin requests, so I would guess that either your request didn't follow CORS rules, or the server doesn't support CORS responses. Here's a link to the standard:

https://www.w3.org/TR/cors/

[Nate Tinkler]

I'm seeing the same behavior as OP.  I'm making a CORS request using pp::URLLoader which completes successfully (both the preflight OPTIONS request as well as the actual POST), however Open() returns PP_ERROR_NOACCESS (-7).

I'm doing this using a pexe loaded into the context of a normal webpage.  I'm not doing extension development (where the same request works just fine, with the same settings and options).

I know the requests have completed successfully because I can watch the entire exchange using the page's dev tools.

One possible issue: I am currently forcing the CORS preflight response using Fiddler.  I've considered that the issue could be setting Access-Control-Max-Age to 1 in the preflight response, and then not including the same Access-Control-Allow-Origin header in the POST response, so I'm going to see if I can modify that response to also include the CORS security headers.  However this is strange behavior.  I can clearly see the request be completed with the dev tools, but I'm still getting PP_ERROR_NOACCESS as the return from Open().

Request data below:

Here is the original OPTIONS request made by the PNaCl component using URLLoader:

1. Request URL:
   https://api.ionic.com/v2.2/keys/fetch
2. Request Method:
   OPTIONS
3. Status Code:
   200 Fiddler CORSPreflightAllow
4. Remote Address:
   127.0.0.1:8888
1. Response Headersview source
1. Access-Control-Allow-Credentials:
   true
2. Access-Control-Allow-Headers:
   content-type
3. Access-Control-Allow-Methods:
   POST
4. Access-Control-Allow-Origin:
   http://localhost:9000
5. Access-Control-Max-Age:
   1
6. Content-Length:
   0
2. Request Headersview source
1. Accept:
   */*
2. Accept-Encoding:
   gzip, deflate, sdch, br
3. Accept-Language:
   en-US,en;q=0.8
4. Access-Control-Request-Headers:
   content-type
5. Access-Control-Request-Method:
   POST
6. Cache-Control:
   no-cache
7. Connection:
   keep-alive
8. Host:
   api.ionic.com
9. Origin:
   http://localhost:9000
10. Pragma:
    no-cache
11. Referer:
    http://localhost:9000/
12. User-Agent:
    Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36

Here is the Corresponding POST request, also made by the URLLoader

1. Request URL:
   https://api.ionic.com/v2.2/keys/fetch
2. Request Method:
   POST
3. Status Code:
   200 OK
4. Remote Address:
   127.0.0.1:8888
1. Response Headersview source
1. Connection:
   keep-alive
2. Content-Length:
   631
3. Content-Type:
   application/json
4. Date:
   Tue, 28 Feb 2017 20:47:06 GMT
5. Server:
   nginx
6. Strict-Transport-Security:
   max-age=31536000
7. Strict-Transport-Security:
   max-age=31536000
8. X-Ionic-Server:
   federation
2. Request Headersview source
1. Accept:
   */*
2. Accept-Encoding:
   gzip, deflate, br
3. Accept-Language:
   en-US,en;q=0.8
4. Cache-Control:
   no-cache
5. Connection:
   keep-alive
6. Content-Length:
   428
7. Content-Type:
   application/json; charset=utf-8
8. Host:
   api.ionic.com
9. Origin:
   http://localhost:9000
10. Pragma:
    no-cache
11. Referer:
    http://localhost:9000/
12. User-Agent:
    Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36