Output Log File Through Ajax In Django

I have followed an SO's accepted answer on how to read the log file in Django from /var/log/gateway from here and I managed to output the file on terminal like here. 2013-05-09T11:

Solution 1:

Well, you can use an idea like this:

Using GET parameters you can control the view's method like this:

defLogs(request):
    whole_file = Trueif request.GET.get('whole_file') == 0:
        whole_file = False
    return_string = ''withopen('../../../../../var/log/gateway') as f:
        whileTrue:
            line = f.readline()
            if line:
                return_string += line + '<br>'# <br> is for breakline html, do it your wayifnot whole_file: break# break if you only need first linereturn HttpResponse(line)

This way, you include a variable inside the get parameter that tells your view whether to return the whole log file (first time) or just the first line (next times).

Then in your ajax you will have to include a way to insert GET parameters to the url. You use the {{url}} tag an I'm not quite sure how to do it with it but I'm sure you'll find something in the doc, if you can't then try some other approach like an static string (not very pretty) or create your own custom tag for it.

This would be an example of your possible javascript:

$.ajax({
    type: "GET", 
    url : "/ajax_log/?whole_file=0", //this will request the whole filesuccess: function (data) {
            $("#output").append(data);
            setTimeout("doUpdate()", 2000);
    }
});
}

setTimeout("doNextUpdate()", 2000);

functiondoNextUpdate(){

    $.ajax({
        type: "GET", 
        url : "/ajax_log/?whole_file=1", //this will request the just the first line            success: function (data) {
                $("#output").append(data);
                setTimeout("doUpdate()", 2000);
        }
    });
    }
}

That is my idea to accomplish what you want. I hope it helps.

Solution 2:

I've found a way to solve this is by doing the Server-Sent Event

On server side, I use django-sse that is dependent on sse

import os
from django.conf import settings
from django.views.generic import View
from django_sse.views import BaseSseView
import time
from django.utils.timezone import now
from datetime import datetime
from django.utils.timezone import now
from dateutil import parser

classMySseEvents(BaseSseView):
    defiterator(self):
        whileTrue:
            ifnot os.path.exists('/var/log/gateway'):
                file('/var/log/gateway', 'w+').close()
            withopen('/var/log/gateway') as f:
                whileTrue:
                    #get the current time
                    currenttime = now()
                    #read a line from gateway
                    line = f.readline()
                    if line:
                        #split the line read into 4 sectionstr = line.split(' ',3)
                        #compare if the time from the log file is less than the current time
                        logtime = parser.parse(str[0])
                        if logtime >= currenttime:
                            #print when the log is written after the current time
                            output = '%s: %s' % (datetime.strftime(logtime,'%d/%m %H:%M %p'), str[3])
                            self.sse.add_message("line", output)
                            time.sleep(1)
                            yield

The if logtime >= currenttime: check that I did above is to make sure that html only print out the logs after the time the page is loaded not the whole log file.

Then on the HTML5 side I did similar to what the example made by the author shown on the first link that I have provided.

<divid="tab9"class="tab_content"><table><tr><td><p> Shows the records of the logs on gateway.</p><divstyle="border:1px solid; height: 200px; width: 850px; overflow: auto;"id="output"></div></td></tr></table></div><script>
$(document).ready(function() {
    var source = newEventSource('/gtwy/logging/');
    var events_dom = $("#output");

    source.addEventListener("line", function(e) {
        events_dom.append(e.data + "<br>");
    });
});
</script>

Using this, I managed to display the log as it is available. The only problem that I face is to create the gateway file itself that it needs permission because I'm trying to create it in /var/log.