docs/en-US/signing-api-calls-python.xml

<?xml version='1.0' encoding='utf-8' ?>
<!DOCTYPE section PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
<!ENTITY % BOOK_ENTITIES SYSTEM "cloudstack.ent">
%BOOK_ENTITIES;
]>

<!-- Licensed to the Apache Software Foundation (ASF) under one
 or more contributor license agreements.  See the NOTICE file
 distributed with this work for additional information
 regarding copyright ownership.  The ASF licenses this file
 to you under the Apache License, Version 2.0 (the
 "License"); you may not use this file except in compliance
 with the License.  You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing,
 software distributed under the License is distributed on an
 "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 KIND, either express or implied.  See the License for the
 specific language governing permissions and limitations
 under the License.
-->

<section id="signing-api-calls-python">
    <title>How to sign an API call with Python</title>
    <para>To illustrate the procedure used to sign API calls we present a step by step interactive session
          using Python.</para>
    
    <para>First import the required modules:</para>
    <programlisting>

 <![CDATA[
$python
Python 2.7.3 (default, Nov 17 2012, 19:54:34) 
[GCC 4.2.1 Compatible Apple Clang 4.1 ((tags/Apple/clang-421.11.66))] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import urllib2
>>> import urllib
>>> import hashlib
>>> import hmac
>>> import base64
 ]]>
    </programlisting>
   
    <para>Define the endpoint of the Cloud, the command that you want to execute and the keys of the user.</para>
    <programlisting>
 <![CDATA[

>>> baseurl='http://localhost:8080/client/api?'
>>> request={}
>>> request['command']='listUsers'
>>> request['response']='json'
>>> request['apikey']='plgWJfZK4gyS3mOMTVmjUVg-X-jlWlnfaUJ9GAbBbf9EdM-kAYMmAiLqzzq1ElZLYq_u38zCm0bewzGUdP66mg'
>>> secretkey='VDaACYb0LV9eNjTetIOElcVQkvJck_J_QljX_FcHRj87ZKiy0z0ty0ZsYBkoXkY9b7eq1EhwJaw7FF3akA3KBQ'
  ]]>
    </programlisting>
    <para>Build the request string:</para>
    <programlisting>
 <![CDATA[
>>> request_str='&'.join(['='.join([k,urllib.quote_plus(request[k])]) for k in request.keys()])
>>> request_str
'apikey=plgWJfZK4gyS3mOMTVmjUVg-X-jlWlnfaUJ9GAbBbf9EdM-kAYMmAiLqzzq1ElZLYq_u38zCm0bewzGUdP66mg&command=listUsers&response=json'
  ]]>
    </programlisting>

    <para>Compute the signature with hmac, do a 64 bit encoding and a url encoding: </para>
    <programlisting>
  <![CDATA[
>>> sig_str='&'.join(['='.join([k.lower(),urllib.quote_plus(request[k].lower().replace('+','%20'))])for k in sorted(request.iterkeys())]) 
>>> sig_str
'apikey=plgwjfzk4gys3momtvmjuvg-x-jlwlnfauj9gabbbf9edm-kaymmailqzzq1elzlyq_u38zcm0bewzgudp66mg&command=listusers&response=json'
>>> sig=hmac.new(secretkey,sig_str,hashlib.sha1)
>>> sig
<hmac.HMAC instance at 0x10d91d680>
>>> sig=hmac.new(secretkey,sig_str,hashlib.sha1).digest()
>>> sig
'M:]\x0e\xaf\xfb\x8f\xf2y\xf1p\x91\x1e\x89\x8a\xa1\x05\xc4A\xdb'
>>> sig=base64.encodestring(hmac.new(secretkey,sig_str,hashlib.sha1).digest())
>>> sig
'TTpdDq/7j/J58XCRHomKoQXEQds=\n'
>>> sig=base64.encodestring(hmac.new(secretkey,sig_str,hashlib.sha1).digest()).strip()
>>> sig
'TTpdDq/7j/J58XCRHomKoQXEQds='
>>> sig=urllib.quote_plus(base64.encodestring(hmac.new(secretkey,sig_str,hashlib.sha1).digest()).strip())
  ]]>
    </programlisting>

    <para>Finally, build the entire string and do an http GET:</para>
    <programlisting>
  <![CDATA[
>>> req=baseurl+request_str+'&signature='+sig
>>> req
'http://localhost:8080/client/api?apikey=plgWJfZK4gyS3mOMTVmjUVg-X-jlWlnfaUJ9GAbBbf9EdM-kAYMmAiLqzzq1ElZLYq_u38zCm0bewzGUdP66mg&command=listUsers&response=json&signature=TTpdDq%2F7j%2FJ58XCRHomKoQXEQds%3D'
>>> res=urllib2.urlopen(req)
>>> res.read()
'{ "listusersresponse" : { "count":3 ,"user" : [  {"id":"7ed6d5da-93b2-4545-a502-23d20b48ef2a","username":"admin","firstname":"admin","lastname":"cloud","created":"2012-07-05T12:18:27-0700","state":"enabled","account":"admin","accounttype":1,"domainid":"8a111e58-e155-4482-93ce-84efff3c7c77","domain":"ROOT","apikey":"plgWJfZK4gyS3mOMTVmjUVg-X-jlWlnfaUJ9GAbBbf9EdM-kAYMmAiLqzzq1ElZLYq_u38zCm0bewzGUdP66mg","secretkey":"VDaACYb0LV9eNjTetIOElcVQkvJck_J_QljX_FcHRj87ZKiy0z0ty0ZsYBkoXkY9b7eq1EhwJaw7FF3akA3KBQ","accountid":"7548ac03-af1d-4c1c-9064-2f3e2c0eda0d"}, {"id":"1fea6418-5576-4989-a21e-4790787bbee3","username":"runseb","firstname":"foobar","lastname":"goa","email":"joe@smith.com","created":"2013-04-10T16:52:06-0700","state":"enabled","account":"admin","accounttype":1,"domainid":"8a111e58-e155-4482-93ce-84efff3c7c77","domain":"ROOT","apikey":"Xhsb3MewjJQaXXMszRcLvQI9_NPy_UcbDj1QXikkVbDC9MDSPwWdtZ1bUY1H7JBEYTtDDLY3yuchCeW778GkBA","secretkey":"gIsgmi8C5YwxMHjX5o51pSe0kqs6JnKriw0jJBLceY5bgnfzKjL4aM6ctJX-i1ddQIHJLbLJDK9MRzsKk6xZ_w","accountid":"7548ac03-af1d-4c1c-9064-2f3e2c0eda0d"}, {"id":"52f65396-183c-4473-883f-a37e7bb93967","username":"toto","firstname":"john","lastname":"smith","email":"john@smith.com","created":"2013-04-23T04:27:22-0700","state":"enabled","account":"admin","accounttype":1,"domainid":"8a111e58-e155-4482-93ce-84efff3c7c77","domain":"ROOT","apikey":"THaA6fFWS_OmvU8od201omxFC8yKNL_Hc5ZCS77LFCJsRzSx48JyZucbUul6XYbEg-ZyXMl_wuEpECzK-wKnow","secretkey":"O5ywpqJorAsEBKR_5jEvrtGHfWL1Y_j1E4Z_iCr8OKCYcsPIOdVcfzjJQ8YqK0a5EzSpoRrjOFiLsG0hQrYnDA","accountid":"7548ac03-af1d-4c1c-9064-2f3e2c0eda0d"} ] } }'
  ]]>
    </programlisting>
    
 </section>