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Bitcoin => Development & Technical Discussion => Topic started by: vess on August 03, 2010, 03:49:49 PM



Title: Authentication, JSON RPC and Python
Post by: vess on August 03, 2010, 03:49:49 PM
Hi all,

Does anyone have jsonrpc or something similar working with HTTP Authentication? I'm trying to hit up my bitcoin server with python over JSON-RPC, and of course, getting authorization errors from the new server.

I couldn't find much about this online, surprisingly, so thought I'd ask here.


Title: Re: Authentication, JSON RPC and Python
Post by: vess on August 03, 2010, 05:20:44 PM
Update: Here is the current state of my hackish code:

postdata = jsonrpc.dumps({"method": 'getbalance', "params":'','id':'jsonrpc'})

req = urllib2.Request('http://127.0.0.1:8332', postdata)
      

base64string = base64.encodestring( '%s:%s' % ('username','rpcpassword'))[:-1]
authheader =  "Basic %s ." % base64string
req.add_header("Authorization",authheader)
      
handle = urllib2.urlopen(req)
      
print handle.read()


If username or password is wrong, then I get an Authorization error from the server as expected.

Otherwise, I get nothing, just a closed connection.

Any leads or tips?


Title: Re: Authentication, JSON RPC and Python
Post by: nelisky on August 03, 2010, 05:42:51 PM
Did you see http://bitcointalk.org/index.php?topic=528.msg4923#msg4923 (http://bitcointalk.org/index.php?topic=528.msg4923#msg4923) ? That might be the problem... I had read somewhere about python urllib and bitcoing not playing along, but curl had no issues. Can't find that thread though.


Title: Re: Authentication, JSON RPC and Python
Post by: vess on August 03, 2010, 06:02:00 PM
Thanks for the pointer, interesting, but not what seems to be affecting me.

Here's my current code (running on Google App Engine)

postdata = jsonrpc.dumps({"method": 'getbalance', "params":'','id':'jsonrpc'})
req = urllib2.Request('http://127.0.0.1:8332', postdata)
userpass = 'user:a'.encode('base64')[:-1]
authheader =  "Basic %s" % userpass
req.add_header("Authorization",authheader)
handle = urllib2.urlopen(req)
json_response = handle.read()
self.response.out.write (json_response)

This yields a HTTPError: HTTP Error 500: Internal Server Error

from the GAE local python script.


using
   postdata = jsonrpc.dumps([{"jsonrpc": "2.0","method": 'getbalance', "params":'','id':'1'}])

Yields the same result.


Title: Content-Length header and 500 (was Re: Authentication, JSON RPC and Python)
Post by: jgarzik on August 03, 2010, 06:09:08 PM
Thanks for the pointer, interesting, but not what seems to be affecting me.

Here's my current code (running on Google App Engine)

postdata = jsonrpc.dumps({"method": 'getbalance', "params":'','id':'jsonrpc'})
req = urllib2.Request('http://127.0.0.1:8332', postdata)
userpass = 'user:a'.encode('base64')[:-1]
authheader =  "Basic %s" % userpass
req.add_header("Authorization",authheader)
handle = urllib2.urlopen(req)
json_response = handle.read()
self.response.out.write (json_response)

This yields a HTTPError: HTTP Error 500: Internal Server Error

This is a verified bug in bitcoin.

bitcoin requires the Content-Length header, but several JSON-RPC libraries do not provide it.  When the Content-Length header is absent, bitcoin returns 500 Internal Server Error.


Title: Re: Authentication, JSON RPC and Python
Post by: vess on August 03, 2010, 06:43:29 PM
What you say is true, but urllib2 does send Content Length.

In my case, we had a datatypes problem which Gavin helped me find: params needs to get a list in python, so

"params" : []

will work.
"params" : ""

did not.

With that amendation, my second sample code works well now. Hope it's helpful to others.


Title: Re: Content-Length header and 500 (was Re: Authentication, JSON RPC and Python)
Post by: Gavin Andresen on August 03, 2010, 06:56:44 PM
bitcoin requires the Content-Length header, but several JSON-RPC libraries do not provide it.  When the Content-Length header is absent, bitcoin returns 500 Internal Server Error.
Can you be more specific about which JSON libraries don't provide Content-Length ?  It'd be nice to document that.



Title: Re: Content-Length header and 500 (was Re: Authentication, JSON RPC and Python)
Post by: jgarzik on August 03, 2010, 06:58:58 PM
bitcoin requires the Content-Length header, but several JSON-RPC libraries do not provide it.  When the Content-Length header is absent, bitcoin returns 500 Internal Server Error.
Can you be more specific about which JSON libraries don't provide Content-Length ?  It'd be nice to document that.

The two JSON RPC libs available at CPAN (Perl), and a compliant C lib that I wrote locally to verify the behavior.


Title: Re: Authentication, JSON RPC and Python
Post by: aceat64 on August 03, 2010, 07:56:32 PM
Another issue I noticed with bitcoind's JSON-RPC is that by default there is no user, and PHP's fopen() function does not try to send the authentication information if no user was specified.

For example, this URL does not work:
Quote
"http://:password@127.0.0.1:8332/"
But this one does:
Quote
"http://username:password@127.0.0.1:8332/"

I had to set the "rpcuser" in my node's bitcoin.conf file in order to get PHP to play nicely.


Title: Re: Authentication, JSON RPC and Python
Post by: vess on August 03, 2010, 08:31:15 PM
I encountered this as well: there's no documentation as to what auth string should be accepted in the case of no user.

It's probably best to require rpcuser and rpcpassword in future versions is my two cents. This is generally what's expected from an HTTP Auth anyway.


Title: Re: Content-Length header and 500 (was Re: Authentication, JSON RPC and Python)
Post by: satoshi on August 03, 2010, 09:26:26 PM
bitcoin requires the Content-Length header, but several JSON-RPC libraries do not provide it.  When the Content-Length header is absent, bitcoin returns 500 Internal Server Error.
Can you be more specific about which JSON libraries don't provide Content-Length ?  It'd be nice to document that.
I guess we should try to support the case where there's no Content-Length parameter.  I don't want to rip and replace streams though, even if it has to read one character at a time.

Edit: That is, assuming there actually are any libraries that don't support Content-Length.


Title: Re: Content-Length header and 500 (was Re: Authentication, JSON RPC and Python)
Post by: Gavin Andresen on August 03, 2010, 10:52:10 PM
The two JSON RPC libs available at CPAN (Perl), and a compliant C lib that I wrote locally to verify the behavior.
Perl's LWP module definitely sets the Content-Length header.  I would've been surprised if it didn't, since it is required by HTTP 1.0 and the HTTP 1.1 spec says clients 'SHOULD' set it.

After some struggle, I got the first JSON::RPC library (http://search.cpan.org/~makamaka/JSON-RPC-0.96/lib/JSON/RPC.pm) at CPAN to work:
Code:
use JSON::RPC::Client;
use Data::Dumper;
 
my $client = new JSON::RPC::Client;

$client->ua->credentials(
   'localhost:8332', 'jsonrpc', 'my rpcusername' => 'my rpcpassword'   # Replace with real user/pass
    );
my @foo = $client->ua->credentials('localhost:8332', 'jsonrpc');
print "@foo\n";

my $uri = 'http://localhost:8332/';
my $obj = {
    method  => 'getinfo',
    params  => [],
 };
 
my $res = $client->call( $uri, $obj );
 
if($res){
    if ($res->is_error) {
        print "Error : ", $res->error_message;
    }
    else {
        print Dumper($res->result);
    }
}
else {
    print $client->status_line;
}
The struggle was setting the realm to 'jsonrpc' (it is fussy about that).  I'll document that on the wiki.



Title: Re: Authentication, JSON RPC and Python
Post by: jgarzik on August 04, 2010, 04:24:16 AM
Content-Length is definitely not sent on Fedora 12 and Fedora 13, will investigate further.  Will check RHEL/CentOS too.