Nov 9 2010

Required Reading for Creating and Deploying a WCF REST Service on IIS7

Deploying a REST service with Windows Communication Foundation (WCF) is great, because it’s very powerful, but it can also be enormously frustrating.

First of all, start by reading the whitepaper.
http://msdn.microsoft.com/en-us/library/dd203052.aspx

This will give you a great overview on how to construct your methods, and how to label them in order to have them exposed correctly by REST.

Next, you need to create your web.config file. Use webhttpbinding for REST.

Lastly, deployment:

How to use https for WCF services in IIS7

How to rewrite your URLs to get rid of the lame .svc extension

I am posting a small demo project, hopefully it’s useful to someone. Simply implement the API interface as you see fit, and the rest basically does itself. You’ll notice the web.config includes a SOAP binding for legacy Microsoft clients to use if they wish.

Link: API_Template


Aug 11 2010

Select DataSet and number of total rows with one stored procedure

when you want to write a search using .net and MSSQL, it’s a pain. This is because you’re forced to select every row in the table and then only display a small subset of it. This works okay for tables that have a few hundred rows, as query caching can make this faster. But what happens when you’re searching a table with half a million rows?

Unless you’re a complete masochist, you’re doing to want to split this into a more manageable data set, otherwise you’re gonna eat all the memory on your server. But this means that you can no longer use the DataSet.Tables[0].Rows.Count property to figure out how many rows you have. You can write a second stored procedure that’ll count the rows. But who wants to clog up their database with tons of stored procedures for no reason? Let’s consolidate it into one.

So what does this look like?

First: the stored procedure.

We’ll use output parameters to pass the row count back to our code


create procedure [dbo].[Search]
@searchText varchar(512), @recordsToReturn INT, @pageNumber INT, @numberofrows INT OUTPUT
AS

-- get the page we want to view
select * from
(
select *, ROW_NUMBER() OVER (ORDER BY creation_timestamp DESC) AS row from [table] where [table].columnName like '%' + @searchText + '%'
)
AS results WHERE row between (@pageNumber - 1) * @recordsToReturn + 1 and @pageNumber*@recordsToReturn;

-- get the total number of rows, not just the subset we want
set @numberofrows = (select count(*) from [table] where [table].columnName like '%' + @searchText + '%')

END

Now the C# (this’ll work in VB too, but feel free to convert it yourself)


SqlConnection conn = new SqlConnection();
conn.ConnectionString = ".....your connection string here.....";
conn.Open();

DataSet returnData = new DataSet();

SqlDataAdapter da = new SqlDataAdapter( "SearchMessages", conn);
da.SelectCommand.CommandType = CommandType.StoredProcedure;

da.SelectCommand.Parameters.Add("@searchText", SqlDbType.VarChar).Value = "bob";
da.SelectCommand.Parameters.Add("@recordsToReturn", SqlDbType.Int).Value = 10;
da.SelectCommand.Parameters.Add("@pageNumber", SqlDbType.Int).Value = 1;

//number of rows
SqlParameter outputParameter = new SqlParameter("@numberofrows", SqlDbType.Int, 2);
outputParameter.Direction = ParameterDirection.Output;

da.SelectCommand.Parameters.Add(outputParameter);

da.Fill(returnData, "theData");

int numberOfRowsInDataSet = (int)outputParameter.Value;

da.Dispose();
conn.Close();

Best of luck! As always, leave a message in the comments if you have questions


Jul 9 2010

MySQL Duplicate Function

Sometimes you want the ability to duplicate (clone) entities in mySQL. But duplicating their children can be a huge pain! Here’s how:

/* parent table */
insert into [parent table]
select 0, [field1, field2, field3] from [tablename] where [parent table primary key] = [parent table object ID]

/* child table */
insert into [child table]
select 0, [field1, field2, field3], (select max([parent table primary key]) from [parent table]) from [child table] where [parent table primary key] = [parent table object ID]

important note! make sure that you don’t select the primary key of the table. instead, select 0, and the auto_increment function will automatically figure out the correct primary key

As always, if you have questions, post em in the comments!


Mar 15 2010

Pure PHP Pagination

So, for a while I’ve been looking for a ridiculously simple way to paginate data stored in a table. And while I love PHP, it just doesn’t come with some of the free things I take for granted in .Net

Today, while working on a pretty simple plugin, I wanted to add this functionality, and I didn’t want to waste a bunch of time. I was given a link to this great script: http://www.warkensoft.com/2009/12/paginated-navigation-bar/

It took me about a minute to implement the functionality. I then spent another 5 minutes doing CSS and that was it. Done. I’m not usually one for link sharing, but this made my life much easier. Hopefully it can make yours easier too.

The solution is pure PHP, no javascript required. Some day, I may try to expand upon this to include javascripty goodness, because that’s pretty much the only thing that could make it better


Mar 5 2010

ASP.Net 301 Redirect


<script runat="server">
private void Page_Load(object sender, System.EventArgs e)
{
Response.Status = "301 Moved Permanently";
Response.AddHeader("Location","http://www.new-url.com");
}
</script>


Jan 20 2010

mysql command doesn’t work in OS X snow leopard

So you install mySql on your mac, and it’s working great, but then you go into terminal to run a mysqldump or something, and it doesn’t work!

you get a message something like:

-bash: mysqldump: command not found

so how do you fix this? well, copy and paste the following into your terminal window and press enter:

echo export PATH="/usr/local/bin:/usr/local/sbin:/usr/local/mysql/bin:$PATH" >> ~/.profile

source ~/.profile

whoa, whoa, you say. what is this doing? It makes it so that when you type any command into the terminal, it does a check of these folders before giving you the “command not found” error.

If you want to undo it, you can always edit your .profile, or just delete it.


Jan 11 2010

Run JavaScript function every n seconds


//tell javascript to run a function in 1 second
setTimeout ("myFunction()", 1000 );

function myFunction(){
//do stuff

//once the function is finished, queue this function up to run again in 1 second
setTimeout ( "myFunction()", 1000 );
}


Sep 12 2009

Get latitude and longitude of an address using google maps

Google doesn’t make it easy to show you the latitude and longitude of an address you search in google maps, but there’s an easy way to get the info.

  1. go to google maps, type the address, and click search
  2. once you’ve found it, go to your address bar and clear what’s in it
  3. paste: javascript:void(prompt('',gApplication.getMap().getCenter())); into the address bar
  4. use the coordinates for whatever you wish!

Aug 13 2009

VirtualHostX and mod_rewrite

To enable mod_rewrite manually, see: OS X server tips but if you are using VirtualHostX it changes your default config file. Add the following code to the Directives box:


Options FollowSymLinks
AllowOverride All AuthConfig
Order deny,allow
Deny from all

if you’re using the new version of VirtualHostX, make sure that you select Directory from the dropdown, then use:


Options FollowSymLinks
AllowOverride All AuthConfig


Jun 10 2009

WordPress plugin DB access framework

While designing a recent WordPress plug-in for TruthMedia that was designed to follow MVC, I had an awful lot of database work to do, and it needed to all be properly secured, which was a lot of work, and while making a rather large change to the way the database worked, I realized that writing all the db code by hand was crazy inefficient.

So I wrote a class that you can extend with any model class of your own, and it will automatically have create, read, update, and delete functionality with no more work required. It also uses all of the WordPress security features to properly escape everything and prevent injection. Although, if you can crack it I’d love to hear from you!

Click here to download!

This is how it works:

  1. Create a new class (ex. person)
  2. Give that class instance variables (ID, FirstName, LastName, Address, PhoneNumber, PostalCode, HairColour…)
  3. Make sure that you add accessor methods (getters and setters) for the ID (although it’s good practice to have them for all instance variables). Depending on your project, it may be a good idea to run stripslashes() on your string get functions so that they don’t show up with escaping. You may want to run WordPress’ attribute_escape() on setters, however, again, depending on your set up this may be unnecessary.
  4. Write your SQL code to create a table named (wordPress prefix)(plugin prefix)person (ex. wp_wec_person)
  5. Make sure you call your primary Key personID **This is very important, without this, the system breaks down**
  6. If you wish to store variables in this class, you can modify them to be private, and they won’t be written to the database

In your class, extend the class name, so for example:

class person extends wec_db {

var $ID;

var $FirstName;

function __construct($id = null, $autoload = true){

//If we are given an ID
if(!empty($eventID)){

$this->setID($eventID);


if
($autoPopulate){

$this->read();

}

}

}

//getters and setters, and any other methods for this object

}

Setup Note: to keep your plugin from stepping on the toes of others, make sure you change the prefix at the top of the class. Also, changing the name of the class to (plugin prefix)db (example:wec_db) will make sure that it doesn’t interfere with anyone else’s if they’re using this class!

Usage:

Create / Add

$person = new person();

$person->setFirstName(‘Joe’);

$person->setLastName(‘Blow’);

$person->add();

Read

$person = new person($personID);

Update

$person = new person($personID);

–or–

$person = new person($personID, false);

$person->setFirstName(‘Jane’);

$person->update();

Delete

$person = new person($personID, false);

$person->delete();

Post any questions in the comments! I’d love to hear from you!