Error pasing arguments to python script from javascript

Question

I have an AJAX function to send an argument and retrieve some json object from a python script. I try to send the value from an input text to the script

AJAX code

function ajax_get_json(){
    var results = document.getElementById("results");
    var hr = new XMLHttpRequest();
    var tipo = document.getElementById('tipo').value;
    var atributo = " " +tipo;
    document.getElementById('texto').innerHTML = atributo;
    hr.open("GET", "prov1.py", + atributo, true);
    hr.responseType = "JSON";
    hr.setRequestHeader("Content-Type", "application/json", true);
    hr.onreadystatechange = function() {
            if(hr.readyState == 4 && hr.status == 200) {
                    var data = JSON.parse(hr.responseText);
                        results.innerHTML = "";
                        for(var obj in data){
                                results.innerHTML +="<tr><td>"+ data[obj].id+"</td><td>"+data[obj].nombre+"</td><td>"+data[obj].tipo+"</td></tr>";
                        }
            }
    }
    hr.send(null);
    results.innerHTML = "requesting...";
}

my python script is this

#!/usr/local/bin/python2.7
import sys
import cx_Oracle
import json
import cgi
import cgitb
cgitb.enable()

form = cgi.FieldStorage()
tipo = form.getvalue('tipo')

#print "Content-Type: text/html; charset=utf-8\n\n";
print "Status: 200 OK"
print "Content-type: application/json\n";
#print
lst_proveedores=[]
conn_str = 'user/pass@database'
conn = cx_Oracle.connect(conn_str)
c = conn.cursor()
c.execute(""" select id_proveedor, nombre, tipo from mpc_proveedores where tipo = '%s' """ %tipo)
for row in c:
    record1 = {"id":row[0], "nombre":row[1], "tipo":row[2]}
    lst_proveedores.append(record1)
json_string = json.dumps(lst_proveedores)
print json_string
conn.close()

In command line the script work's fine (python prov1.py tipo=MMS) and retrieve from the database the data, but when I try to retrieve the data from AJAX the script send me an empty json object. using firebug I check the response and only appear [].

I think the AJAX function have some error, because appear send the argument empty (python prov1 tipo=). I am new with AJAX and no sure if I am not using properly the functions in AJAX or is in the python script. If anybody knows a better way to retrieve the data, let me know please

Help please!!!!

score 0 · Answer 1 · edited May 23 '17 at 12:29

Couple things:

Change
var atributo = " " +tipo;
into
var atributo = "?tipo=" + encodeURIComponent(tipo);
You should check your code for SQL injection vulnerabilities
You're sending the Content-Type header when you make a request to the server, even though you have no request body. (GET requests never have request bodies.) Won't break anything, but you should probably take it out.
responseType is part of HTML5, and is not availible in all browsers.

Best of luck!

Error pasing arguments to python script from javascript

1 Answers1