CS001231 - Receiving system logs info in WRT

From Forum Nokia Wiki

ID	CS001231	Creation date	December 18, 2008
Platform	S60 5th Edition	Tested on devices	Nokia 5800 XpressMusic
Category	Web Runtime (WRT)	Subcategory	System information

Keywords (APIs, classes, methods, functions): Service.Logging, Service.Logging.GetList()

Overview

This code snippet shows how to retrieve information from system logs using the methods from the Logging Platform Service of the S60 Web Runtime (introduced in S60 5th Edition).

The device.getServiceObject("Service.Logging", "IDataSource") method is used to obtain access to the service object for the Contact Service API.

After setting the values for criteria.Type, the IDataSource.GetList(criteria) method is used to retrieve items from system logs.

Source file: LoggingView.html

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <script type='text/javascript' src="LoggingView.js"></script>
        <title></title>
    </head>
    <body onload="init()">
        <div id="inputdata">
            <select id="eventtype">
                <option>EKLogCallEventType</option>
                <option>EKLogDataEventType</option>
                <option>EKLogFaxEventType</option>
                <option>EKLogShortMessageEventType</option>
                <option>EKLogPacketDataEventType</option>
            </select>
            <button onclick="doRefresh()">Refresh</button><br/>
        </div>
        <hr/>
        <!-- table for showing existing items -->
        <table id="maintable" cellspacing='1' cellpadding='1' border='1'>
        <tr><td>1</td><td>2</td><td>3</td><td>4</td></tr>
        </table>
    </body>
</html>

Source file: LoggingView.js

// logging system service object
var logger; 
// system error code
var noItemsErrorCode = 1012; 
 
/**
 * Initializes the widget
 */
function init() {
    // Obtain the service object
    try {
        logger = device.getServiceObject("Service.Logging", "IDataSource");
    } catch(err) {
       alert( "error receiving Logging service handle" );
       return;
    }
 
    // Refreshing info
    doRefresh();
}
 
/**
 * Refreshes information in table
 */
function doRefresh() {
    var criteria = new Object();
    criteria.Type = "Log";
    criteria.Filter = new Object();
    criteria.Filter.EventType =
        document.getElementById('eventtype').selectedIndex;
 
    // making a call to service to receive a list of suitable items
    var logs;
    try {
        logs = logger.IDataSource.GetList(criteria);
    }catch(err) {
        alert("error receiving log items");
        return;
    }
 
    var table = document.getElementById('maintable');
    // cleaning table and adding header
    while(table.rows[0] != undefined) {
        table.deleteRow(0);
    }
    table.insertRow(0);
    table.rows[0].innerHTML = "<th>EventType</th><th>EventDuration</th>" +
        "<th>Subject</th><th>Description</th>";
 
    if(logs.ErrorCode != 0) {
        // If the error code is not "no suitable items", show an alert.
        // Otherwise just leave the function.
        if(logs.ErrorCode != noItemsErrorCode) {
            alert( logs.ErrorMessage );
        }
        return;
    } else {
        // filling table with received data
        var table = document.getElementById('maintable');
        var i;  // iterator
        var item; // pointer to item in received list
        for(i = 0; (item = logs.ReturnValue.getNext()) != undefined; ++i) {
            table.insertRow(i + 1);
            var result = "<td>";
            if(item['EventType'] != undefined) {
                result += item['EventType'];
            }
            result += "</td><td>";
            if(item['EventDuration'] != undefined) {
                result += item['EventDuration']
            }
            result += "</td><td>";
            if(item['Subject'] != undefined) {
                result += item['Subject'];
            }
            result += "</td><td>";
            if(item['Description'] != undefined) {
                result += item['Description'];
            }
            result += "</td>";
            table.rows[i + 1].innerHTML = result;
        }
    }
}

Postconditions

After loading a table with all logs is shown.
Pressing the "Refresh" button refreshes the table.
The drop-down list allows you to choose what type of logs you would like to see.

Supplementary material

You can view the source file and executable application in the attached ZIP archive. The archive is available for download at Media:Receiving_system_logs_info_in_WRT.zip.

Community: Wiki