Tutorial by Examples: e

PostgreSQL is an actively developed and mature open source database. Using the psycopg2 module, we can execute queries on the database. Installation using pip pip install psycopg2 Basic usage Lets assume we have a table my_table in the database my_database defined as follows. idfirst_namelast_n...

Loops can be nested, to preform iterated task within another iterated task. Consider the following loops: ch = 'abc'; m = 3; for c = ch for k = 1:m disp([c num2str(k)]) % NUM2STR converts the number stored in k to a charachter, % so it can be concatanet...

If you want have a long text to display in the context, you need to set a custom content. For example, you have this: But you wish your text will be fully shown: All you need to do, is to add a style to your content like below: private void generateNotification(Context context) { ...

Following example shows steps involved in initializing a view from XIB. This is not a complex operation but exact steps need to be followed in order to do it right way first time, avoiding exceptions. How does loadNibNamed Works Main steps are: Create XIB Create class .h and .m Define outlet...

The first thing to do when taking your Meteor app offline is to create some visual indication of whether the local client app is connected to the server or not. There are lots of ways to do this, but the simplest way is to probably do something like this: Template.registerHelper('getOnlineStatus', ...

One of the easier steps is adding the appcache. Appcache will allow your application content to load even when there is no internet access. You won't be able to get any data from your mongo servers, but the static content and assets will be available offline. meteor add appcache

Finally, we want to get some of our dynamic data to be stored offline. meteor add ground:db Lists = new Meteor.Collection("lists"); GroundDB(Lists); Todos = new Meteor.Collection("todos") GroundDB(Todos);

The appcache will cause some confusion in your development workflow, because it hides Meteor's auto-updating features. When you turn off the server component of your app, the client portion in your browser will continue working. This is a good thing! But, you don't get the immediate feedback that ...

The first step to logging is simply to run Meteor from the shell, and you'll get the server logs in the command console. meteor The next step is to pipe the contents of std_out and std_err to a logfile, like so: meteor > my_app_log.log 2> my_app_err.log

Once you have your server side logging in place, it's time to hop over to the client side. If you haven't explored the console API, be prepared for a treat. There's actually all sorts of things that you can do with the built in Console API that's native to every Chrome and Safari installation. So mu...

Once you have both your server-side logging running, and your client side development tools, you can start looking at Meteor specific extensions like the Meteor Chrome DevTools Extension. This lets you actually observe server logging in the client! Because the database is everywhere. As is logging. ...

The following example is from 0.5 - 0.7 days, and illustrates how to log an error when the database hasn't populated the client side cursor yet. Template.landingPage.postsList = function(){ try{ return Posts.find(); }catch(error){ //color code the error (red) console.error(erro...

The following uses the Chrome Logging API. If the .group() syntax is used in multiple templates, it will graphically organize the console logs from different templates into a hierarchical tree. You can also see how to inspect the current data context, and how to stringify data. Template.landingPa...

Simple example of using the Chrome Logging API. Template.landingPage.events({ 'click .selectItemButton':function(){ // color code and count the user interaction (blue) console.count('click .selectItemButton'); } });

Logging can often clutter up the console, so it's common to define log levels to control what detail of data is getting logged. A common pattern is to specify a log level variables. var DEBUG = false; var TRACE = false; Template.landingPage.events({ 'click .selectItemButton':function(){ ...

Some teams find that they want to leave console log statements in their code, but not have them display in production. They will override the logging functions if a variable isn't set (possibly an environment variable). Additionally, this may qualify as a security feature in some situations. if (...

A special mention should be made for the community developed LogLevel package. It appears to strike a balance between being lightweight and simple to use, while working well with Meteor's bundle pipeline and preserving line numbers and filenames. https://atmospherejs.com/practicalmeteor/loglevel ...

This deployment guide assumes you're using an Ubuntu server, and are either self-hosting or using an Infrastructure as a Service (IaaS) provider, such as Amazon Web Services or Rackspace. Your Ubuntu server needs to be running a daemon for launching other apps, for which we recommend the Upstart ser...

One favored approach to deploying to a server is to use Git or GitHub. This basically involves logging into your server, moving to the directory you want to run your app from, then cloning your files directly from GitHub. You then build your app on the server. This approach ensures that platform spe...

Alternatively, you may want to build your application, and then deploy it.. cd myapp meteor build --directory ../output cd .. scp output -r username@destination_host:/var/www/myapp-production