Xero Python API Access

// Updated code from here(https://help.interfaceware.com/kb/writing-a-xero-adapter) to work with python 3.x
// Requires openssl and curl in the environment path variable
// Run with python [filename].py

#!/usr/bin/python
import time, os, base64, urllib.parse as urllib, random, collections, binascii;

def OutputTable(Name, Table):
   print(Name);
   for key, value in Table.items():
      print(" ", key, ": ", value);

def OauthEscape(Value):
   Result = urllib.quote_plus(Value);
   Result = Result.replace("+", "%20"); # cheap hack
   return Result;

def ConcatenateSigParams(Params):
   X = "";
   for K,V in Params.items():
      X = X+K+'='+OauthEscape(V)+'&'
   return X[:-1]; # remove the last character

def AuthInfo(Auth):
   R = "";
   for K,V in Auth.items():
    R = R+' '+K+'="'+V+'",'
   return R

CONSUMER_KEY='INSERT CONSUMER KEY HERE'
Url = 'https://api.xero.com/api.xro/2.0/ENDPOINT/GUID/history'
Params = {}
#Params['where'] = 'Name == "Kevin Macey"' # uncomment and remove GUID/history and add contacts as endpoint to search contacts

Headers = {}

Auth = {}
Auth['oauth_nonce'] = str(int(time.time())) + str(int(random.random()*1000000));
Auth['oauth_timestamp'] = str(int(time.time()));
Auth['oauth_version'] = '1.0';
Auth['oauth_signature_method'] = 'RSA-SHA1';
Auth['oauth_consumer_key'] = CONSUMER_KEY;
Auth['oauth_token'] = CONSUMER_KEY;

# Merge GET params with oauth params
AllParams = {}
for key, value in Params.items():
   AllParams[key] = value;
for key, value in Auth.items():
   AllParams[key] = value;

OrderedParams = collections.OrderedDict(sorted(AllParams.items()));
SortedParamAuthString = ConcatenateSigParams(OrderedParams);
SignatureText = 'GET&'+OauthEscape(Url)+"&"+OauthEscape(SortedParamAuthString);

temp = open("text.txt", "wb");
temp.write(SignatureText.encode('utf-8'));
temp.close();
os.system("cat text.txt | openssl dgst -sha1 -sign privatekey.pem -binary > signature.bin")
SignatureBinary = open( "signature.bin", 'rb' ).read();
Signature=base64.b64encode(SignatureBinary);

Headers['Authorization'] = 'OAuth' + AuthInfo(Auth) + ' oauth_signature="' + OauthEscape(Signature) + '"'
Headers['Accept'] = "application/json"
print("==========================================================================")
OutputTable('Params', Params);
print("==========================================================================")
OutputTable('Oauth Headers', Auth);
print("==========================================================================")
OutputTable('All Parameters', AllParams);
print("==========================================================================")
OutputTable('Ordered Parameters', OrderedParams);
print("==========================================================================")
OutputTable('Headers', Headers);
print("==========================================================================")
print("Sorted Parmam String: ", SortedParamAuthString);
print("==========================================================================")
print("Signature Text: ", SignatureText);
print("==========================================================================")
print("Signature : ", Signature);
print("==========================================================================")
CurlCommand = "curl -vv"

# We have to escape the " characters to \" for the windows command line
for key, value in Headers.items():
   CurlCommand += ' --header \'' + key + ": " + value.replace('"', '\"') + "\'"

CurlCommand += " \"" + Url + "\"?";
# Add the GET variables
for key, value in Params.items():
   CurlCommand += key + "=" + urllib.quote_plus(value) + "&";
# Strip off the last & character
CurlCommand = CurlCommand[:-1]

print(CurlCommand);
os.system(CurlCommand);