The are two ways of accessing the Salesforce API via Simple Object Access (SOAP) and REspresentational State Transfer (REST). To programmatically upload files or attachments to Salesforce using Python we evaluate first how to do it using REST.

Looking at these docs Insert or Update Blob Data uploading via REST is only possible if your organization is in the Salesforce pilot program. For now we will implement the upload via SOAP and using a Python library to access Salesforce named Beatbox .

Below is a command line script I coded to allow one to upload file to Salesforce. For local testing I set the parentId of the upload file to an Account named Ron Local or set with other value appropriately, in production you would normally set the uploaded file to an Email id. See also file upload limitations set by Salesforce. After successful upload you can verify the uploaded file by going to the profile page of the Account Ron Local or whatever name of the Account you used.

#!/usr/bin/env python

import sys
import os 
import beatbox

sf = beatbox._tPartnerNS
svc = beatbox.Client()

def main(username, password, file):
    """ For local testing I initially created an Account object in Salesforce
    that has name 'Ron Local'. In production replace parentId with desired id. ie Email id
    """
    loginResult = svc.login(username, password)
    print "sid = " + str(loginResult[sf.sessionId])
    print "welcome " + str(loginResult[sf.userInfo][sf.userFullName])

    account_id = ""
    aq = svc.query("select Id from Account where Name = 'Ron Local'")
    print "query size = " + str(aq[sf.size])
    
    if (str(aq[sf.done]) == 'true'):
        for rec in aq[sf.records:]:
            print str(rec[0]) + " : " + str(rec[1])
            account_id = str(rec[1]) 

    sObject = {
        'type': 'Attachment',
        'Body': base64_encode( read_file(file) ),
        'ParentId': account_id,
        'IsPrivate': False,
        'Name': extract_filename(file),
    } 

    qr = svc.create(sObject)
    if str(qr[sf.success]) == 'true':
        print "upload successfull: id " + str(qr[sf.id])
    else:
        print "upload failed."

def read_file(path):
    output = None
    with open(path) as f:
        output = f.read()
    return output

def base64_encode(content):
    return content.encode(encoding='base64', errors='strict')

def extract_filename(path):
    return os.path.basename(path)


if __name__ == '__main__':
    if len(sys.argv) != 4:
        print "upload2sf.py username password file-path"
    else:
        main(sys.argv[1], sys.argv[2], sys.argv[3])

Usage: Install Beatbox via pip or easy_install:

pip install beatbox
python upload2sf.py email@somewhere.com password+security-token /Downloads/mastering-vi-vim.pdf