captureing output of nodejs via PHP exec - javascript

I am trying to get the output from my node.js script via PHP exec thats wrapped inside an ajax call I am able to call it i think and get some feed back, but console.log doesn't seem to return to the output var
This is how i call the script
$ex = exec('/usr/local/bin/node '.$path.'doAjax.js >/dev/null/ 2>&1 &',$_POST,$out);
var_dump($ex,$out);
In doAjax.js i do
console.log('hhhhhhhhhhhhh');
But all i get for output is
string(0) "" array(0) { }
Is there another way todo output or capture it ?

yes the code and output where switched, but then i always got code 8
i semi solved this problem by moving code to the httpd doc root and changing to shell_exec
though i still need to make sure apache won't be able to display the node code

Related

Javascript Value of Variable not updating in Servlet

I have simplified my Code to breakdown the Problem and to have a simple Example with a Timestamp for whats actually going wrong.
So please not be suprised why i do a AJAX call, this is for the real functionality of the Servlet.
Its a Servlet and the follwing code is part of a JSP page, im Working on JAVA 1.7 and a Tomcat 7. I run it in Firefox and Chrome.
My goal is to retrieve a value from a Java method and write it on the servlet page into the DIV "ContentCharts".
The Problem is that Javascript does not update the vaule of "zeit" and always writes the same Timestamp into the DIV-Container and on the Console
$(document).ready(function()
{
function ausgabe()
{
<%
GregorianCalendar now = new GregorianCalendar();
DateFormat df = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.LONG);
String JZeit = df.format(now.getTime());
System.out.println("FKT ausgabe zeit:"+ JZeit);
%>
var zeit='<%=JZeit %>';
console.info('Zeit:', zeit);
document.getElementById('ContentCharts').innerHTML = zeit;
}
$("#subtab2").click(function()
{
$.ajax
(
{
url:'overview',
data:{dbname:this.className},
type:'get',
cache:false,
success:function(){ausgabe();},
error:function(){alert('error');}
}
);
}
}
To test this I write the value of the JAVA varible "Jzeit" into the Serverlogs and get this (Click to see the Picture) results when I click the buttons three times. As you can see in the Picture here I get the right Timestamps.
Now I have also post the Value of the JS varialbe "zeit" into the Firebug Console. And now i get the Wrong time Stamps (Click to see the Picture)
The Content in the DIV is refreshing but here is the same Problem like in the Console, its always the same Timestamp.
These are my thoughts and Questions:
Why has the JS variable the wrong value when its right in JAVA?
Is there any option to say JS that it has to update the variable?
Could it be that JS saves the answers of the JAVA code and does not run it anymore, but runs the upper JAVA Code Snippet because there is no direct connection betwen JS and JAVA, like a value allocation?
How can i fix my Problem?
If you need more Informations to help me please ask for it.
You're a bit confused about the ajax pattern.
Note that anything you write in <%= jsp tags %> will be rendered on the server, then sent to the client where it will never change. Therefore your ausgabe function will always return the same result when it is called. Subsequent calls to the function will not make repeated server requests, which is the behavior you're observing.
To fix this, the success function in your ajax call should take an argument which will be instantiated with the response from the server. The java code you've written in the jsp tags in the ausgabe function should be moved to the server and any variables you need should be returned from the overview endpoint. Then, the ausgabe function should be refactored to take an argument containing the server-calculated values, and update your page as desired.
Here is some reading on ajax requests:
https://developer.mozilla.org/en-US/docs/AJAX/Getting_Started
http://api.jquery.com/jquery.ajax/

how to execute command prompt from php

As am very new to php.
I have the following command as:
cd E:\PHP\home_php\img\tmp
E:
montage -mode concatenate -tile 3x3 *.png result.png
I want to execute the command from cmd.exe in php(if possible from javascript too).
Right now I have to execute .bat file but that file has some static value. I need to pass few dynamic value. How can I open cmd with required command.
I tried php montage but I need .bat kind of thing in cmd from php/JS.
Try this :echo exec('your command');
http://php.net/manual/en/function.exec.php you can also use backticks for some weird reason: http://php.net/exec
You can use number of PHP funcions to execute system code:
shell_exec("your command") would execute code and return an output to you
system("your command", $returnCode) would execute your command and return numerical status of your command
exec("your command", $outputArray, $returnCode) would execute command and return your output line by line in outputArray + return code
Before asking such a simple question you really should first go to http://php.net and search for required functionality instead of asking it here.

Node JS - Express.js get query with multiple parameters

I'm quite new to JavaScript and Node JS and I have a such a situation. When I try to call get of express.js with a single parameter everything works fine, but when I try to call get with more than one parameter, it trims the query.
For example I have such call and function
app.get('path/data', myFunc);
// in another file
function myFunc(req, res) {
// do some stuff
}
When the url is path/data?id=5 or path/data?name=foo everything is fine. But when I use for example url like path/data?id=5&name=foo in myFunc I get url as path/data?id=5. So I get url's first part - what is before & sign.
Now what am I doing wrong? Is there something that I'm missing? How can I get whole url in myFunc without being trimmed?
Use
app.get('path/data?:id?:name')
And for retrieving the values, use req.query.id and req.query.name.
For accessing the REST api, you need to hit:
http://localhost:8080/demo?id=3&name=stack
So, by this you can add multiple parameters in your api.
Hope this helps.
I found the problem. I was requesting via curl and it turns out that shell command trims in case of there is an & in the url. So there is a need no add quotes like this
curl "path/data?id=5&name=foo"

Executing PHP script with button in Javascript

Here's the break down: My problem is two fold, i want to use a button to call to my php script, which in turn calls to my nodejs script running on my little internal test server (this is all done local for now).
Here is my html + script pull:
<input type="submit" value="Save Sketch" id= "run_system">
</body>
<script>
$('#run_system').on('click', function(){
$.ajax({
url : 'exec.php',
type : "GET"
}).done(function(data){
console.log(data);
});
});
</script>
and here is my php script:
<?php exec('node screenshot.js //place holder url that gets dumped into js file// "); ?>
so my problem is that the previous call to this php is not executing this. Everything i've googled says that this exec("") should run my nodejs script. What am i missing?
I am guessing the type : GET is incorrect, tried not having that line, putting POST in there, nothing seems to work though
Oh one more addition, so when i run the above all it does is print what was in the php file to the console, doesn't actually run the script
One of the issues is that the exec is executing the command, but you're not capturing / returning the output of that command. You can probably add an echo or print before exec to return the output to the AJAX request.
You might also want to bind to the submit event to handle form submissions as well as submit button clicks, but that would be bound to the form itself.
Ultimately though, I would recommend that you contemplate handling this exec by adding a simple HTTP server to your screenshots.js node script (or something that wraps it) and handle the AJAX request with that. Will likely need to add a Access-Control-Allow-Origin exemption.

Codeigniter - sending json to script file

I query the db i my model like so
function graphRate($userid, $courseid){
$query = $this->db->get('tblGraph');
return $query->result();
}
My controller gets data back from my model and I json encode it like so
if($query = $this->rate_model->graphRate($userid, $courseid)){
$data['graph_json'] = json_encode($query);
}
$this->load->view('graph', $data);
And thats returns me a json object like so
[
{"id":"1","title":"myTitle","score":"16","date":"2013-08-02"},
{"id":"2","title":"myTitle2","score":"17","date":"2013-09-02"},
{"id":"3","title":"myTitle3","score":"18","date":"2013-10-02"}
]
In my view graph I'm loading an js file
<script type="text/javascript" src="script.js"></script>
Now I want to use $data that is being sent from my controller to my view, to my external script.js to use as labels and data to feed my chart. But How do I get that Json data to my external script.js so I can use it?
1 more thing about the json data, isn't it possible to get the output of the json data as
{
"obj1":{"id":"1","title":"myTitle","score":"16","date":"2013-08-02"},
"obj2":{"id":"2","title":"myTitle2","score":"17","date":"2013-09-02"},
"obj3":{"id":"3","title":"myTitle3","score":"18","date":"2013-10-02"}
}
The problem isn't a Codeigniter problem, it's a javascript scope/file inclusion/where-do-i-get-my-data-from problem.
I run into this all the time and have used these solutions:
naming my php files with .php extensions and loading them as if they're views.
Just putting the script that needs data from a view IN the view file where it's used
Using an ajax request in my included js file to hit a controller and get json data.
I use #2 most frequently (for things like datatables where I WANT the js code right there next to the table it's referencing.
I use #1 occasionally, but try NOT to do that because it means some .js files are in my webroot/js dir and some are in teh application/views directory, making it confusing for me or anyone else who wants to support this project.
#3 is sometimes necessary...but I like to avoid that approach to minimize the number of requests being made and to try to eliminate totally superfluous requests (which that is).
You need to print the result of the output json string to the html generated file.
But you need to parse the string with some script. I would recommend you: http://api.jquery.com/jQuery.parseJSON/
For the second question. It is possible by doing:
$returnValue = json_encode(
array (
"obj1" => array("id"=>"1","title"=>"myTitle","score"=>"16","date"=>"2013-08-02"),
"obj2" => array("id"=>"2","title"=>"myTitle2","score"=>"17","date"=>"2013-09-02"),
"obj3" => array("id"=>"3","title"=>"myTitle3","score"=>"18","date"=>"2013-10-02"),
)
);
Print the output using PHP like:
echo json_encode($query);
Then from the client-side (where JavaScript resides) load that JSON that you printed using PHP. This can be done easily using JQuery.
Like this:
$.get("test.php", function(data) {
alert("Data Loaded: " + data);
});
You can find more information about this here: http://api.jquery.com/jQuery.get/
Now you'll need to parse this data so that JavaScript can understand what you got as text from the server. For that you can use the JSON.parse method on the "data" object in the aforementioned example. Once parsed, you can use the object like any other object in JavaScript. You can find more information about JSON.parse here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse
I hope that helps.

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