DRY CRUD!
That is, of course, "Don't repeat yourself".
With my evedb.info site I have to essentially rsync two databases whilst mangling schema. The process will take FOREVER (Mainly because I'm not multithreading this process) but it's automated.
I kept having to write CRUD methods in all of my controllers to deal with updating evedb.info as I talked about in this linked post and they were ALL the same. So being the lazy programmer I am I put them all in the ApplicationController:
Here's the update method
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def update
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singular = params[:controller].singularize
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camel = singular.camelize
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klass = camel.constantize
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@temp = klass.new params[singular]
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@real = klass.find params[:id]
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changes = object_diff(@real,@temp)
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logger.info "Changes: #{changes.inspect}"
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if changes.keys.size == 0
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render :nothing => true, :status =>
k -
return
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end
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if @real.update_attributes(changes)
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render :nothing => true, :status => k
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else
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render :json => @real.errors.to_json, :status => 400
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end
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end
By abusing Rails's constantize I can mangle the controller's name ("corporations") into the model it's handling: Corporation and treat it klass as if it was actually spelled Corporation. Personally I think that is very cool.
object_diff is a method I wrote to find the differences between two ActiveRecord::Base derrived objects. Loop through attributes hash and note things that change. changes is those attributes that have changed.
The only part I haven't been able to DRY out is the index method which always returns YAML for my scripts but only the IDs of the objects.
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if params[:format] != 'yaml'
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@corporations = Corporation.find normal finder
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end
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respond_to do |format|
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format.html
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format.yaml { render :text => Corporation.find(:all, :select => 'id', rder => 'id').to_yaml }
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end
But I don't think I can DRY it out becase Corporation YAML finder actually selects another column that my script uses. Oh well.
[...] That’s nice. A google search reveals that quite a lot of people write code like [...]
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