Styjun

I'm able to select and read a local file using the code below:

Structure of my local file i'm reading looks like this.

27/03/19 12:36:18:193 LINE 1

27/03/19 12:36:18:198 LINE 2

27/03/19 12:36:18:198 LINE 3 LINE 3.1

27/03/19 12:36:18:199 LINE 4

27/03/19 12:36:18:199 LINE 5 LINE 5.1

27/03/19 12:36:25:045 LINE 6

My problem is I want to be able to split the file into an array and output parts as index

i.e.

#0| 27/03/19 #1| 12:36:18:199 #2| LINE 5 #3| LINE 5.1
data[2] = LINE 5

Also be able grep for a keyword and out put that .

Nb. the file is a server log so would need to be read in realtime.

Thanks in advance for your answers,
Cody

<img id='output'>
<script>
 var openFile = function(event) 
 var input = event.target;

 var reader = new FileReader();
 reader.onload = function()
 var text = reader.result;
 console.log(reader.result);
 ;
 reader.readAsText(input.files[0]);
 ;
</script>

Reading Files

If it's a server log and you wish to handle this client side in realtime then you'll need to:

Server

• Create a nodejs server that watches your log file for any modifications which can be done with fs.Watch and provides a socket connection
  

Client

• Create a web socket that receives notifications from your server whenever your log file has changed with the data sent (note the server web connection library also offers a client side one which is supported on all browsers, check their examples to understand quickly)


• Whenever new data is sent simply call the script below and update your view

Why create a separate server to handle this ?

• Well if you're not running a nodejs server already, then creating a nodejs server is quick and easy.




• It's a feature outside of what your main server is focused on doing

Handling Log Data:

Partial implementation on how to read the contents of your log file. You'll need to determine a pattern to be able to seperate LINE 5 LINE 5.1 as this current script simply splits on white spaces. If each LINE does not have any spaces then it'll work.

const data = `
27/03/19 12:36:18:193 LINE 1

27/03/19 12:36:18:198 LINE 2

27/03/19 12:36:18:198 LINE 3 LINE 3.1

27/03/19 12:36:18:199 LINE 4

27/03/19 12:36:18:199 LINE 5 LINE 5.1

27/03/19 12:36:25:045 LINE 6
`

const res = data
.trim()
.split(/n+/)
.map(line=>line.split(/s/));

console.log(res)

After parsing the file contends by line, you can try the below snippet to get the contends with index , Assuming the line separators are "white spaces".

function parseContends(inputString)
 if(inputString != null) [];
 var stringArray = new Array();
 for(var i =0; i < string.length; i++)
 stringArray.push(string[i]);
 
 
 console.log(stringArray);


parseContends("27/03/19 12:36:18:198 LINE 3 LINE 3.1");

The Above Snippet has been updated in the Code Pen , You can see the output in console.

[https://codepen.io/redhatvicky/pen/QoXLYw][1]