Reviewing RavenBurgerCo: What Could be Improved?
There are two things that I would change in the RavenBurgerCo sample app.
The first would be session management, I dislike code like this:
I would much rather do that in a base controller and avoid manual session management. But that is most a design choice, and it ain’t really that important.
But what is important is the number of indexes that the application uses. We have:
- LocationIndex
- DeliveryIndex
- DriveThruIndex
And I am not really sure that we need all three. In fact, I am pretty sure that we don’t. What we can do is merge them all into a single index. I am pretty sure that the reason that there were three of them was because there there was a bug in RavenDB that made it error if you gave it a null WKT (vs. just recognize this an a valid opt out). I fixed that bug, but even with that issue in place, we can get things working:
public class SpatialIndex : AbstractIndexCreationTask<Restaurant>
{
public SpatialIndex()
{
Map = restaurants =>
from restaurant in restaurants
select new
{
_ = SpatialGenerate(restaurant.Latitude, restaurant.Longitude),
__ = restaurant.DriveThruArea == null ?
new object[0] :
SpatialGenerate("drivethru", restaurant.DriveThruArea),
___ = restaurant.DeliveryArea == null ?
new object[0] :
SpatialGenerate("delivery", restaurant.DeliveryArea)
};
}
}And from then, it is just a matter of updating the queries, which now looks like the following:
Getting the restaurants near my location (for Eat In page):
return session.Query<Restaurant, SpatialIndex>()
.Customize(x =>
{
x.WithinRadiusOf(25, latitude, longitude);
x.SortByDistance();
})
.Take(250)
.Select( ... );Getting the restaurants that deliver to my location (Delivery page):
return session.Query<Restaurant, SpatialIndex>()
.Customize(x => x.RelatesToShape("delivery", point, SpatialRelation.Intersects))
// SpatialRelation.Contains is not supported
// SpatialRelation.Intersects is OK because we are using a point as the query parameter
.Take(250)
.Select( ... ) ;Getting the restaurants inside a particular rectangle (Map page):
return session.Query<Restaurant, SpatialIndex>()
.Customize(x => x.RelatesToShape(Constants.DefaultSpatialFieldName, rectangle, SpatialRelation.Within))
.Take(512)
.Select( ... );Note that we use DefaultSpatialFieldName, instead of indexing the location twice.
And finally, getting the restaurants that are applicable for drive through for my route (Drive Thru page):
return session.Query<Restaurant, SpatialIndex>()
.Customize(x => x.RelatesToShape("drivethru", lineString, SpatialRelation.Intersects))
.Take(512)
.Select( ... );And that is that.
Really great project, and quite amazing, both client & server code. It is simple, it is elegant and it is effective. Well done Simon!
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