Where's My Serrated Knife?
At the risk of seeming strident or going on out on a limburger, I hereby assert that Attribute Routing (caps deliberate) is the best thing since sliced bagels.
The ASP.NET Web API REST extravaganza (and its brethren) use, where possible, convention over configuration. That is to say, you can name a method in your Controller Get (something), such as GetAJob()
or GetReal()
, and HTTP GET
methods will invoke it.
If you have multiple Get
methods, as long as they have a unique signature, all is well.
But what if you have two parameterless Get
methods, such as one to get the count of items (returning an int
) and another to get all the items (returning a collection of a particular type)?
Cue the Bugles (not the Bagels, the Bugles)!
Never fear - Attribute Routing is here!
Here's an example of two Controller "GET"
methods that have no arguments:
public int GetCountOfDuckbilledPlatypiRecords()
{
return _DuckbilledPlatypusRepository.GetCount();
}
public IEnumerable<duckbilledplatypus> GetAllDuckbilledPlatypi()
{
return _DuckbilledPlatypusRepository.GetAll();
}
If I run the Web API app and enter in the browser: "http://localhost:28642/api/DuckbilledPlatypi" I confuse the Charles Dickens out of the router, which can only say:
"Multiple actions were found that match the request: Int32 GetCountOfDuckbilledPlatypiRecords() on<br /> type HandheldServer.Controllers.DuckbilledPlatypiController System.Collections.Generic.IEnumerable`1<br />[HandheldServer.Models.DuckbilledPlatypus] GetAllDuckbilledPlatypi() on type<br /> HandheldServer.Controllers.DuckbilledPlatypiController"
But if I add Attribute Routing, like so:
[Route("api/DuckbilledPlatypi/Count")]
public int GetCountOfDuckbilledPlatypiRecords()
{
return _DuckbilledPlatypusRepository.GetCount();
}
[Route("api/DuckbilledPlatypi/GetAll")]
public IEnumerable<duckbilledplatypus> GetAllDuckbilledPlatypi()
{
return _DuckbilledPlatypusRepository.GetAll();
}
...and then enter "http://localhost:28642/api/DuckbilledPlatypi/Count" I get 42 (or whatever - depends on how many Platypi I
have, of course.)
And If I enter http://localhost:28642/api/DuckbilledPlatypi/GetAll, I get, as hoped, the entire collection back.
The Custard and Mustard Cavalry
So: when you need diverse "queries" in your Controller, it's Attribute Routing to the rescue!
Note: The new update (ASP.NET MVC 5.1) improves attribute routing, even. See the official release notes.
Speaking of rescue, if you like this tip, be sure to generously tip the next member of a waitstaff that serves you.
I am in the process of morphing from a software developer into a portrayer of Mark Twain. My monologue (or one-man play, entitled "The Adventures of Mark Twain: As Told By Himself" and set in 1896) features Twain giving an overview of his life up till then. The performance includes the relating of interesting experiences and humorous anecdotes from Twain's boyhood and youth, his time as a riverboat pilot, his wild and woolly adventures in the Territory of Nevada and California, and experiences as a writer and world traveler, including recollections of meetings with many of the famous and powerful of the 19th century - royalty, business magnates, fellow authors, as well as intimate glimpses into his home life (his parents, siblings, wife, and children).
Peripatetic and picaresque, I have lived in eight states; specifically, besides my native California (where I was born and where I now again reside) in chronological order: New York, Montana, Alaska, Oklahoma, Wisconsin, Idaho, and Missouri.
I am also a writer of both fiction (for which I use a nom de plume, "Blackbird Crow Raven", as a nod to my Native American heritage - I am "½ Cowboy, ½ Indian") and nonfiction, including a two-volume social and cultural history of the U.S. which covers important events from 1620-2006: http://www.lulu.com/spotlight/blackbirdcraven