Implementing Log Services in Angularjs

This experience uses ANGULARJS to customize a logging service.

In Angularjs, some of the service's formulations are:

var app = Angular.module (' app ', []); App.provider (function() {...}); App.service (function() {}); App.factory (function() {});

Equivalent to:

function ($provide) {    $provide. Provider (function() {...})}]) App. Config ([function($provide) {    $provide. Service (function() {...})}]) App. Config ([function($provide) {    $provide. Factory ()} (function() { ...});}])

In fact, $provider. Service () and $provider.factory () can also be implemented by $provider.provider () in an injected manner.

function ($provide) {    $provide. Service (function() {        this. Name = "";          this. Author = "";    })}])

The above is equivalent to:

function ($provide, $injector) {    $provide. Provider (function() {       this  function($injector) {        return $injector. Instantiate () (function() {             this. Name = "";             this. Author = "";     });})

Above, that is, the service itself is a provider that can be initialized by $injector to a service.

In the same vein, we write factory:

function ($provide) {    $provide. Factory (function() {        return {name: ', Author: '} ;    })}])

The above is equivalent to:

App. Config ([' $provide ', ' $injector ',function($provide, $injector) {    $provide. Provider (  function() {        thisfunction($injector) {            return $ Injector.invoke (function() {                return {name: ', Author: '}})}    ) }])

Create your own provider

function () {    var color = ' red ';          This function (newcolor) {        = newcolor;    }         function () {        return  color;    }})

We can make some settings in config using Appcolor, the custom provider method.

function (appcolorprovider) {    appcolorprovider.setcolor (' green ');}])

Then inject the Appcolor service into the run.

App.run ([' Appcolor ', Funciton (appcolor) {    console.log (appcolor);}])

Create a log service

Suppose you need the following log format:

<timestamp>-<context>::<method name> (' <message> ')
<timestamp>-<context>: <message>

Create a class about the log:

varLogger =function(context) { This. Context =context;} Logger.getinstance=function(context) {return NewLogger (context);}//AlternativeLogger.supplant =function(str, o) {returnStr.replace (/\{([^{}]*) \}/g,function(A, b) {varR =O[b]; return typeofr = = = ' String ' | |typeofr = = = ' Number '?r:a; })}//format TimeLogger.getformattedtimestamp =Funciton (date) {returnLogger.supplant (' {0}:{1}:{2}:{3} ', [Date.gethours (), Date.getminutes (), Date.getseconds (), Date.getmilleseconds ()]);} Logger.prototype={_log:function(ORIGINALFN, args) {varnow = Logger.getformattedtimestamp (NewDate ()); varMessage = "', Supplantdate = []; Switch(args.length) {//print format:<timestamp>-<context>: <message>             Case1: Message= Logger.supplant ("{0}-{1}:{2}", [Now, This. Context, Args[0]]);  Break;  Case3:                //print Format:<timestamp>-<context>::<method name> (' <message> ')                //The first parameter is a method name                //The second argument is a message                //The third parameter is the objectSupplantdata = args[2]; Message= Logger.supplant ("{0}-{1}::{1} (\ ' {3}\ ')", [Now, This. Context, Args[0], args[1]]);  Break;  Case2:                //Detecting the second parameter type                if(typeofARGS[1] = = = ' String ') {Message= Logger.supplant ("{0}-{1}::{2} (\ ' {3}\ ')", [Now, This. Context, Args[0], args[1]]); } Else{sup;antdata= Args[1]; Message= Logger.supplant ("{0}-{1}:{2}", [Now, This. context.args[0]])                }                 Break; } $log [Originalfn].call (NULL, logger.supplant (message, suppantdata)); }, log:function(){         This. _log (' log ', arguments); }, Info:function(){         This. _log (' info ', arguments); }, warn:function(){         This. _log (' Warn ', arguments); }, Debug:function(){         This. _log (' Debug ', argments); }, Error:function(){         This. _log (' ERROR ', arguments); }};

We may use this log class as follows:

// example is the name of a class or file or module var logger = logger.getinstance (' Example '); Logger.log (' This is a alog '); Logger.warn (' warn ', ' This was a worn '); Logger.error (' This is a {0} ' error {1} ', [' big ', ' hello ']);

The complete code is as follows:

App.provider (' Logger ', [function(){    varIsEnabled =true;  This. Enabled =function(_isenabled) {isenabled= !!_isenabled; }         This. $get = [' $log ',function($log) {varLogger =function(context) { This. Context =context; } logger.getinstance=function(context) {return NewLogger (context); }    //AlternativeLogger.supplant =function(str, o) {returnStr.replace (/\{([^{}]*) \}/g,function(A, b) {varR =O[b]; return typeofr = = = ' String ' | |typeofr = = = ' Number '?r:a; })    }    //format TimeLogger.getformattedtimestamp =Funciton (date) {returnLogger.supplant (' {0}:{1}:{2}:{3} ', [Date.gethours (), Date.getminutes (), Date.getseconds (), Date.getmillesecon    DS ()]); } Logger.prototype={_log:function(ORIGINALFN, args) {if(!isenabled) {                return; }                    varnow = Logger.getformattedtimestamp (NewDate ()); varMessage = "', Supplantdate = []; Switch(args.length) {//print format:<timestamp>-<context>: <message>                 Case1: Message= Logger.supplant ("{0}-{1}:{2}", [Now, This. Context, Args[0]]);  Break;  Case3:                    //print Format:<timestamp>-<context>::<method name> (' <message> ')                    //The first parameter is a method name                    //The second argument is a message                    //The third parameter is the objectSupplantdata = args[2]; Message= Logger.supplant ("{0}-{1}::{1} (\ ' {3}\ ')", [Now, This. Context, Args[0], args[1]]);  Break;  Case2:                    //Detecting the second parameter type                    if(typeofARGS[1] = = = ' String ') {Message= Logger.supplant ("{0}-{1}::{2} (\ ' {3}\ ')", [Now, This. Context, Args[0], args[1]]); } Else{sup;antdata= Args[1]; Message= Logger.supplant ("{0}-{1}:{2}", [Now, This. context.args[0]])                    }                     Break; } $log [Originalfn].call (NULL, logger.supplant (message, suppantdata)); }, log:function(){             This. _log (' log ', arguments); }, Info:function(){             This. _log (' info ', arguments); }, warn:function(){             This. _log (' Warn ', arguments); }, Debug:function(){             This. _log (' Debug ', argments); }, Error:function(){             This. _log (' ERROR ', arguments);                    }    }; returnLogger; }]}])

The custom logger is turned off globally.

function (loggerprovider) {    loogerprovider.enabled (false);}])

Reference: http://www.webdeveasy.com/service-providers-in-angularjs-and-logger-implementation/

Implementing Log Services in Angularjs