Introduction to Working with Facebook

When writting my application, it happened to be a canvas app, or it was accessed via apps.facebook.com with a iframe to my acctual app. When I would get a new user I would immediatley get a new cookie that was named fbs_APPID within this cookie, most importantly, there was a access token. Now to know any information about a user, one must have one thing, an OAuth access token.

Getting an OAuth access token

Most times you will have a token in the cookies, however on some random times that I never figured out the pattern to, you just don’t have that information there. And as for most apps, you need to know some information about a user, and possibly even post or something of the like with the users permission. However, for protection, Facebook just doesn’t allow any application developer access to their entire database. So to allow only certain access to certain applications, applications are given OAuth tokens, these tokens are user specificic and generally session specific. With these tokens, you could use the later discussed Facebook Graph to get just about any needed data.
The process of getting an OAuth token if it is not in the “fbs_” cookie can be quite strenuous. First you need to redirect the user to the Graph server with certain application-specific parameters. Next, one of the parameters happened to be a call back url, now that url is called and Facebook gives you a code. Using this code and your application secret you can finally get a new OAuth access token. Basically what all these redirects does is allow Facebook to check that this user is acctually logged in and that this user is allowing the application access to this information.

The Facebook Graph

Why they call it the “Graph” I am not quite sure, however it is quite a handy tool. Just heading over to http://graph.facebook.com/me will provide you some basic information about yourself, provided that you are currently logged into Facebook on that browser. Furthermore looking up more information is easy, all you need to know about something is it’s Facebook ID. Everything on Facebook has an ID, from an event to a group, to a person. With people you can even use words like the ones that are for your profile. You can access some basic information on me by going to http://graph.facebook.com/jordan.deloach.
Want other information? It’s easy

• http://graph.facebook.com/me/picture links to that select person’s profile (replace Me with the FB ID of anything on Facebook)
• http://graph.facebook.com/me/home Your news feed
• http://graph.facebook.com/me/feed Your wall
• http://graph.facebook.com/me/movies Your movies.

Obviously there are many more than this, and it as simple as fetching these url’s in your application to get all this data. Check out the Graph API for more examples and the nitty-gritty syntax. You can get all sorts of data on any event, photo, anything really.

Where these two technologies meet

Now the reason that we discussed OAuth tokens was that so you had them in your application for when the time came when you needed some data. Not all data requires a token, in fact any data visible by outside (non-friend) users is visible. However when that no longer cuts it, an access token with proper permissions can get you all the data you need. When applying the access token it is as simple as putting it as a GET argument

https://graph.facebook.com/me/friends?access_token=w5h2kl5jhkleh235hjkl23h5jkwhfklq3

Note: when using an access token you must use HTTPS or a secure connection.

Another note: Me refers to the user who authorized the access token, not the developer.

And another, major note: all data will be returned in JSON Object forrm, so all you need is a few libraries, or if they are included with your language you’re fine.
For Java I used the libraries are JSON.org, they worked just fine.

Now for this application, as I wrote it in a matter of days and released it the day of schedule releases, I had to go with a language I knew very well, and I had to have a reliable, dependable source to host it at. I automatically though of the Google App Engine as it is pretty sweet to play around with and now would be a great time to test it in a live environment. My previous application I had wrote on Google’s free, scalable engine was written in Python. It utilized the amazing Django framework, but I felt like I didn’t really understand the Python language as well as some others. The only other option for selection on the App Engine was Java. This was perfect as I had just completed a summer class on Java and it was extremely fresh in my mind.

Core Java Servlets

Now coming from PHP for web development the idea of Servlets and JSP’s was totally a different way of thinking. With PHP I was used to putting what code I needed to on each page to achieve what needed to be done. With a bit of Python/Django experience, Java’s way was still different, but not as different as PHP to Java. Java’s JSP method reminded me a lot of Django templates, except that JSP’s are a load more powerful. As Django templates (at least from my experience) only allow a few tags, a JSP allows practically any Java code (that would normally go inside a main method) and allows imports and special features unique to JSP’s, like includes. JSP’s includes in fact reminded me some more of Django’s templates with all the splitting up possible of the HTML files.

Now that we briefly know what a JSP is, a servlet is just like a Java class that implements the standard Apache servlet. Within these servlets you have two methods by default doGet(HttpServletRequest req, HttpServletResponse resp) and doPost() with the same arguments. There are a few differences from a standard Java class beyond those previously noted:

resp.getWriter().println(); // to print to the screen you must get the PrintWriter via the resp.getWriter() method
resp.setContentType("text/html"); // must do if you print out any HTML and don't want it to appear as standard text
resp.sendRedirect(String url); // a simple way to send a user to be redirected

There is (obviously) no console input on a web browser, so the standard way to get input via the web is through GET and POST methods. These are handled via the corresponding doGet() and doPost() methods. Now to actually get the value passed, you must know the variable name and use it accordingly.

req.getParameter(String paramName); // where paramName is the ?name=Joe&age=18 name or age

Sometimes you will also find yourself in need of getting an array, from say a multiple choice drop down.

req.getParameterValues(String paramName); // just once and it will return a String[]

Now onto more of the theory behind servlets, and less of the syntax. Now please remember when I say theory, this is just the way I perceive it. In my application if I would have a full blown HTML page, I would always put it in a JSP as it is so simple and better looking. However when there was a simpler page that had a bit more code behind it, I would make that a servlet. An example of a simpler page with more code that I used as a servlet would be my form handlers (any adding or updating interaction with the database), and also I handled the OAuth authentication with servlets.

JSP’s

JSP’s, or Java Server Pages, are a mix between Java code & client-side scripting. It allows you to mix the power of Java and your the models in your MVC framework with the simplicity of a HTML file. You probably see them all over the web, as they are quite effective, especially in larger businesses and universities.
I have not personally gone that far into all the powers of JSP’s but enough to know that I like them. I am not going to try and write a tutorial but just point out a few things I use and a good tutorial or two.
Now one of the simplest, but greatest is the server-side include of static content. This allows you to keep your web pages on the server side leaner and able to easily change base things like headers or footers.

<%@ include file="/include.html" %>

Other useful things to know, if you need to get any parameters or need to mess with the request or response, they are simply called request and response in all JSP’s. So you could use a request.getParameter("id"); for example.
If you need to write anything to the page from within the Java code just throw a out.println(String value); or out.print(String value).

For anything more than what I included check Google for some JSP tutorials or here is a good looking one.

Benefits

I see there being several benefits of using Java as the language behind more complex applications because of it is an object oriented language. It being OO allows code to get so many more times complex. Now, in web development at least, a OO language is only as good as the database that supports it . I happened to be very lucky with Google App Engine as it was powered by a OO database allowing me to store some of my unique data types like “Student”, “Teacher”, “Course”, and “Schedule” in the database and retrieve it like it has been open since it was created. Most of the interface for this was provided in the JDO classes in javax.JDO.
With this and a few classes for getting and selecting certain Students/Teachers/Courses, it was very easy to get exactly the results I want in a few lines of code in a JSP. And I know that in Python and PHP you can have classes and objects, but it’s just not the same as it is in Java. While Java can be pretty strict with it’s types and defining them, it in turn gives a lot of power to create awesome and dynamic applications for the end user.

Finally

As I have been reading in my “Clean Code” book, it is better to take longer and write software better the first time. Better being Javadoc’d and Object-Oriented. If you were to write it the other way, with say PHP or Python and have each script access the relational database, get the results, sort the results into the data you need, and output it correctly, that is so much code duplication. One script could be anywhere from 20% – 50% of the same code over and over, why not just write it great in the beginning in an OO way so the only code duplication you have is one or two lines to load the pre-written-by-you libraries that does all that work in one place, one time.

And sorry Brent I think I like Java Servlets & JSP’s a wee bit more than Python/Django even though I think Django is a great framework and would love if it were written in Java instead, Python just isn’t as big and powerful as Java.

My application, only available for MHS students, allows you to add your schedule (teachers and classes), see who’s in your class, comment and Facebook Like both your teachers and your hours.

It was written on the Google App engine, using an OO (object oriented) database with JSP’s and Core-servlets. I  will be writing a post about this stuff later.

For some who want to complain about how “bad” it is, I remind you this was about 8 days of work. However here is some of my attached code for it. Note: this is only SOME, not all.

socialschedulesSource [zip]

I do not see the “Hello World” that intimidating anymore, for the single reason is that I know what and why all those words are there at the beginning of the file, and the best way for you to get into it is to understand it.

public class HelloWorld {

    public static void main(String[] args) {

        System.out.println("Hello World");

    }

}

The first line is public class HelloWorld. public simply means that from anywhere and by anybody this class can be called. The class simply means that it is a class, as all beginning files in Java will be. The HelloWorld I think should be pretty easy to understand. The second line, public static void main(String[] args)... is a bit more complicated. The public meaning that this method can be called from outside this class. static means that this method can be called without initializing the whole class as an object. void simply means that it returns no value, as methods in the future might, like int or boolean. The next part, main means that this method should be run whenever this program is run, for any Java program to run, there must be a main method. String[] args is probably the strangest part, String is a line of characters, like a word, sentence, anything really. In Java, this [] mean an array, so String[] args means that for it’s parameters it takes an array of Strings. However you won’t deal with this for a while in your Java career. System.out.println... breaks down to System, which is a package (a folder full of classes) and out is a class within the package that deals with output. Finally println is a method (function) which prints the line.

Understanding Strings

Ever wondered why in Java, you see things like int and double and they are lower-cased, but String is capitalized? All class names in Java are capitalized, and so must String be.

String myname = "Jordan";

You are creating a new object (unique version of a class) of the class String. With strings you can do so much more than a primitive type (int, boolean, short, etc.). As myname is an object, it has methods that uniquely work with it.

System.out.print(myname.length()); // prints number of chars in myname

System.out.print(myname.charAt(4)); // prints ‘a' for the 5th char in it

There are many more options, but that will do for examples of how this is an amazing way to store Strings.

More on Classes and Objects

To help you differentiate between classes and objects, I offer the following example.

MathOps.factorial(5); // uses the class MathOps and static method factorial()

MathOps math = new MathOps();

math.factorial(5); // uses the unique object

// another example that shows benefits

ShoppingCart cart1 = new ShoppingCart();

ShoppingCart cart2 = new ShoppingCart();

cart1.add("blanket");

cart1.add("shampoo");

cart2.add("ice cream");

cart1.remove("shampoo");

System.out.println(cart1.list());

System.out.println(cart2.list());

Yes, I have not actually made any of those classes, but those were just for examples, see with the ShoppingCart example, you saw exactly the benefits of the different objects as opposed to storing them in one big class where it would get all mixed up together.

User Input & Reading Files

It is quite strange, but in Java these are EXTREMELY similar so they shall be grouped together. To read user input in Java, one must first look for it.

Scanner s = new Scanner(System.in);

Scanner is a great class. I used to oppose it, but now seeing it’s virsitility, it’s a great class. Anyways what this says is create a new object named “s” that reads System input. To get a line of input is as easy as s.nextLine();

System.out.print("Please enter your name: ");

String name = s.nextLine();

System.out.println("Hello " + name);

Now the reason it was grouped with reading files is because if you want to ready a file, just tell Scanner so.

Scanner s = new Scanner(new File("filename.txt"));

while(s.hasNext()) { // hasNext() returns true as long is there more lines

    System.out.println(s.nextLine());

}

That would print out every line of the file. It is just like reading input, just a different start.

Loops and If’s

If your familiar with PHP this is extremely easy and only requires a paragraph or two.

boolean a  = true;

if(a) {

    // then do this

} else if(!a) {

    // then do this, notice the space between else and if not elseif

} else {

    // else do this

}

if(a) {

    // one line only can use this format

} else {

    // same for loops too

}

for(int i = 0; i < 10; i++) // you can use {} if you want

    System.out.println(i);

while(true) {

    // infinite loop

}

Good Things to Know

Integer.parseInt("123"); // can take a string (like user input) and convert it

Double.parseDouble("2.3"); //ditto

String b = "hey";

b.charAt(0); // gets the a (parameter) character from a string

Conclusion

With just that basic two to three page intro, you should be pretty set. Using just the things desribed here, you can do just about anything text-based. If you want to start working with GUI’s you’ll have to go to google and find a nice tutorial on how to do that. It’s more work, but it is just an extension of this sort of thing.

Glossary

Method (Java) ~ Function (PHP)

Int ~ Medium ranged integers

Double ~ For numbers with a decimal

Boolean ~ True or false

As most of you know * is a wildcard, the cool thing is it can be applied virtually anywhere in the Linux Shell. It’s great for being lazy when you don’t want to complete a whole file name.

sudo nano /etc/apache2/sites-enabled/*

That command would edit the sites-enabled file, it is named ( at least on my server ) something strange like “000-default” and instead of remembering that, just put part of it. And a even more known thing is to use a ~ for your home directory, cool thing is you don’t even need to keep it in /home for it to find it.

cd ~/Pictures/May*9

That command would change directory into Pictures in your home directory and go to the folder that starts with May and ends with 9, such as May 2009

Don’t wait for a command to finish, just list them all at once with &&

sudo apt-get update && sudo apt-get upgrade

The command right there is a great command that simplifies Ubuntu updates to just one line, instead of updating ( finding out what needs to be upgraded ) and acctually upgrading the packages. These commands can really be piled on, like yesterday I used the following:

wget http://localhost:8080/ && cat index.html && rm index.html

I would download a file, print it out, and delete it. All in one command. && is great.

sudo mkdir /media/Data && sudo mount /dev/sdc1 /media/Data

Stop scanning through all that output, find it quickly with grep

This one took me a long time to understand ( not sure why ) but whenever your searching for something in output, just add a “| grep zzzz” at the end to find zzzz. Here is a real life example:

sudo netstat -tupan | grep 8080

That command would look at what program is using port 8080, or another example:

ls -Ra ~ | grep file.txt

That would list all the files in your home directory, ( the R is for recursive so it goes through all the folders in there not just the base one and the a is for all files, even hidden. ) and it would print out anything it finds that has “file.txt” in it.

Important Options on Important Commands

• ls -l lists files with there permissions
• sudo -i become root
• cp -r, mv -r, ls -R, etc. Recursivley do something ( look through all the folders, not just the starting folder )
• any command with -h -h or –help is normally the help output and is almost always there.
• almost any command with -v verbose tells you everything it is doing, great for debugging

Great Commands

• cat read a file without entering it, eg cat file.txt would output the contents of file.txt
• touch create a file without entering it, eg touch file.txt creates file.txt
• “echo ‘text here’ >> file.txt” adds ‘text here’ add the bottom of file.txt, can also use with commands like lshw >> lshw.txt
• lshw -html >> lshw.html lists your hardware with lots of details in a neat html file.
• sudo start/stop/restart servicename like sudo stop mysqld stops mysql

Other Random Things:

• “.” is the present directory, just the period, like cp /etc/apache2/ ./ would copy everything in the apache2 folder to the present directory
• “..” or “../” is the upper directory, apache2′s would be /etc and /bin’s would be / ( great for cd ../ )
• The “d” at the end of things like sshd or mysqld normally stands for daemon
• cron schedules things to run at certain times
• Use public/private keys

11 Reasons to Love Ubuntu:

• Ubuntuforums.org
• Simple website, setup, all around simple
• Apt-get
• Apt-get
• Ubuntu Wiki
• The Ubuntu community
• Most programs have a special install for it, or at least have specific instructions for Ubuntu.
• Wonderful built in software
• 2 Updates a year
• LTS updates
• Ubuntu chartroom is great for instant support

28 Reasons to love Linux:

• Open Source
• Open Source
• Open Source
• Open Source
• Great help base (though Ubuntu’s is superior)
• Anything is possible with the right knowledge
• Gnome
• Reliability
• Free
• Lash / ffmpeg / lspci / lsusb (amazing, simple commands)
• Grep
• Amazing logging (try finding that in windows!)
• File transfer speeds are shown (MAJOR)
• Makes the best servers
• Cron
• Wget / fdisk / DF –H (so many great command)
• Wine (the Windows emulator, not the alcoholic beverage)
• Not graphically weighed down, but still looks good
• You have a choice of gui ( Gnome, KDE, Xfce, etc. )
• You can run just about any sort of server on Linux
• So freaking customizable
• X
• X over SSH
• Great built in support for encryption
• Really easy to start making your own scripts and customizing it just the way you like it.
• Best security, anywhere. No config necessary (but you still can)
• CUPS
• It can run on anything even a 200 MHz processor

24 Reasons to love Unix:

• SSH
• Amazing setup (root /) so much better than C: and D: and E: and F: etc.
• Great integration with PHP, Python, etc.
• Bash / SH
• Mounting is SO easy
• Terminal is worth knowing (cmd.exe is a joke)
• Great built in support for compression (more than just windows zip!)
• Transmission (app)
• Finder/Nautilus are not the ugly  explorer.exe
• Mounting more than a hard drive is possible (network and virtuals)
• You don’t need extras; the basics do it (Ex: ISO making is included in Unix by default)
• Efficiency
• Rarely has Apps act up like Windows (You’ll forget what to do when you see a Don’t Send)
• The Icons look good
• You finally can break away from the start menu of windows.
• Directory/File permissions are worth using
• Directory/File owners are worth using
• Groups are worth using
• Customizabilicity. ( Yes, it’s not a word but even when you can customize your boot loader than is pretty amazing )
• SUDO
• Terminal can look pretty flashy ( compared to cmd.exe )
• It doesn’t lie, it throws files away, it doesn’t recycle them ( attack on the Recycle Bin of Windows )
• It gets along with everyting, Windows, Mac, Linux, Unix always communicates great.
• There is hope for when you have problems

• I have installed a gigabit switch and patch panel. It rocks.
• I have got a server up and running beautifully that my family uses for backups and media streaming
• I am in the middle of setting up a git server on my server.
• I have been messing around with RSA and DSA and PGP keys.
• Finishing up school
• Prepping for taking CIS 200 at K-State. College class at 15 ( Software Design Fundamentals )
• I have become an avid Ubuntu addict.
• Can’t wait to get a Macbook.

“We have to pass the bill so that you can find out what is in it.” Speaker of the House, Nancy Pelosi ( D – California )

Now that we have “passed the bill” we can finally “what is in it.” What’s in it? Good question, we have secret deals for Nebraska and other states, we have $500 billion in cuts to Medicare, $52 billion in Social Security cuts, and taking over the loan industry.

Now those first ones are easy to believe, but that last one “taking over the loan industry?” Yes, sadly it is true. According to a March 22 article of USA Today “The government will shut down private lenders, sell expensive loans to 19 million college students and use the profits to finance ObamaCare.”

This bill is loaded with unfair, important-industry-cutting, profiting crap. After just knowing what is in this wretched bill, it should be enough to show you this bill is not right.

Yes, there are some good effects, but it is how we get there. Just like we can quickly solve the middle east problem with a nuke, it’s an unacceptable way of getting there.

How do the American people feel about this bill?

60% disapprove of this bill! And 57% are disgusted at the Democrats way of getting this past, the secret deals, the close door meetings, etc. Since Obama has been pushing this, Obama has hit his lowest rating ever.  These three statistics clearly show most Americans don’t want this, yet Democrats are using crude and rude tactics to get this in. A final, resounding statistic is 11% currently agree with  congress right now. If that doesn’t make something ring in your head, well… nothing will.

Some evidence of new government power

According to a “Ways and Means” report of the U.S. House, IRS agents now have the right to:

• IRS agents verify if you have “acceptable” health care coverage;
  
• IRS has the authority to fine you up to $2,250 or 2 percent of your income (whichever is greater) for failure to prove that you have purchased “minimum essential coverage;”
  
• IRS can confiscate your tax refund;
  
• IRS audits are likely to increase;
  
• IRS will need up to $10 billion to administer the new health care program this decade;
  
• IRS may need to hire as many as 16,500 additional auditors, agents and other employees to investigate and collect billions in new taxes from Americans; and
  
• Nearly half of all these new individual mandate taxes will be paid by Americans earning less than 300 percent of poverty ($66,150 for a family of four.)

See all those “quotes” are places where its up to the specific IRS agent, how they feel about you, that day, etc. I don’t know about you, but this scares me a little.

What can we/you/I do?

Support the “no”-ers. Those people, Republicans or Democrats, who weren’t affraid of anything, those were able to vote against everyone else. They need support both now and in the upcoming midterms. Another thing we can do is in the midterms, elect those who promise to repeal it.

Right now Senator Jim DeMint has promised a health care repeal bill by the end of the week. The repealing process has started, now it just needs support! Even if it is not successful right away in November when the GOP gains power, the repealing will be in an ever great forward motion. And even if that fails, many think that is what many will care about in the 2012 election, “will you repeal healthcare?”

In Conclusion

I hope this article has been a bipartisan explanation of what is, what is wrong, and what is to come. And I am quite tired, so I shall end this article right now.

Sources:

http://www.cbsnews.com/8301-503544_162-6084818-503544.html

http://www.cbsnews.com/8301-503544_162-6084856-503544.html

http://www.rasmussenreports.com/public_content/politics/obama_administration/daily_presidential_tracking_poll

http://republicans.waysandmeans.house.gov/News/DocumentSingle.aspx?DocumentID=176997

So this is my “make shift gigabit switch and phone switch” as the real 8 gigabit switch and connector pieces are en route. It is connecting my room line and the line to the router as everyone else is yet to get on the bandwagon.