CODEWITHSUNDEEP
javascriptnode.js
Alberto Alibaba
Alberto Alibaba

Reputation: 305

node function result undefined

this function check_auth return always undefined ? cookie is ok result is ok, maybe the problem is the async call if yes how can fix it? I don't wont connection if the function is not satisfied

 function check_auth(req,res){
var cookie=check_cookie(req);
var check_result_ret;
  if(cookie){ 
      console.log("exist cookie: "+cookie);
      var sql    = 'SELECT session_id,username,id FROM session WHERE session_id = ' + connection.escape(cookie);
      connection.query(sql, function(err, results) {
          if (err) throw err;
if (results.length  > 0 && results[0]['session_id'] ==cookie) {
 users[results[0]['session_id']]={username:results[0]["username"],id:results[0]["id"]};
check_result_ret=1;
}else{
             check_result_ret=0;
           }
                  });

}else{
       check_result_ret=0;
  }
 return check_result_ret;
}

server node part

switch (path) {
case '/':
var test=check_auth(request,response);
console.log("result",test);
if(test==1){    
fs.readFile("main.html", 'utf-8', function (error, data) {
 //make somthing
});
}else{
    send404(response);  
}
break; etc....

Upvotes: 0

Views: 162

Answers (1)

Rana Deep
Rana Deep

Reputation: 617

The problem is check_auth returns check_result_ret before the callback function(err, results) of connection.query is called .

I guess you need to read more on how asynchronous programming works .This might help http://www.sebastianseilund.com/nodejs-async-in-practice

maybe this helps,

check_auth(req,res){
...do stuff
  connection.query(sql, function(err, results) {
    if (err) throw err;
    if (results.length  > 0 && results[0]['session_id'] ==cookie) {
      users[results[0]['session_id']]={username:results[0]["username"],id:results[0["id"]};
      check_result_ret=1;
    }
    else{
      check_result_ret=0;
    }
   var test = check_result_ret;
   if(test==1){    
     fs.readFile("main.html", 'utf-8', function (error, data) {
             //make somthing afer reading the file
             anotherAsyncCall(input,options,function(output){
                //do something with output 
             });
     });
   }
   else{
    send404(response);  
   }
})

Upvotes: 1

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