I know there is a lot of information available for passing variables between one controller action and another, both within the same controller and to other controllers.
But what I am trying to do, which I have been unable to find any documentation on, is temporarily store a variable in one controller action, so that it is available when another controller action(within the same controller) is called shortly after.
I tried using an instance variable but it didn't work.
I don't believe I can use flash because that is only for the very next action.
A class variable wouldn't be suitable because it would lead to conflicts if users were doing things simultaneously.
Any other ideas?
You likely want to use the session for this in your controller during first pass:
session[:save_me] = "for next time"
then on the next time in there
if( session[:save_me] )
#do cool stuff here
session[:save_me] = nil
end
Http is stateless so we use a session to pass information from request to request.
Related
When writing a CKAN extension, I can create a custom GET-able method, which automatically receives the context.
e.g.
#side_effect_free
def custom_method(context, data_dict):
# Do something with the context and/or data_dict
The context argument above, which is basically injected by CKAN, contains, among other things, the user object which can be used to identify the user.
In other cases, like for example in a template helper, how can I get access to the user information? Ideally, I would like to have a context object just as above, so that I can call for example package_search and the rest of the actions provided in the toolkit.
Turns out that when calling actions, skipping the context variable will cause ckan to add it later inside the call, so there's no need to provide the context yourself. Also, if you want information on the user, the g variable from Flask has everything you need.
This is about an API handling the validation during saving an object. Which means that the front-end client sends a request to the API to a specific end point, then on the back-end the API creates a new object if the right conditions are meet.
Right now the regular method that we use is that the models has a ruleset for each fields and then the validation is invoked when the save function is invoked, but technically the validation is done right before the object is saved into the database.
Then during today's code review I came across a solution which I wasn't sure if it's a good practice or not. And it was about that the front-end must send a specific parameter to the API every time. This is because other APIs are using our API as well, and we needed to know if the request was sent as and API request or a browser request. If this parameter is present then we want to execute an extra validation function on a specific field.
(1)If I would have to implement it, then I would check the incoming parameter in the service handler or in the controller level, and if I got one, I would invoke the validation right away, and if it fails I would throw an error.
(2)The implementation I saw however adds an extra variable to the model, and sets the model variable when there is an incoming parameter, then validates only when the save function is invoked on the object(which first validates the ruleset defined on the object fields, then saves the object into the database)
So my problem with (2) is that the object now grown bigger with an extra variable that is only related to a specific event. So I would say it's better to implement (1). But (2) also has an advantage, and that is when you create the object on different end point by parsing the parameters, then the validation will work there as well, even if the developer forget to update the code there.
Now this may seems like a silly question because, why would I care about just 1 extra variable, but this is like a bedrock of something good or bad. So if I say this is ok, then from now on the models will start growing with extra variables that are only related to specific events, which I think should be handled on the controller/service handler level. On the other hand the code would be more reliable if it's not the developer who should remember all the 6712537 functionalities and keep them in mind when makes some changes somewhere. Let's say all the devs will get heart attack tomorrow from the excitement of an amazing discovery, and a new developer has to work on the project while he doesn't know about these small details, and then he has to change something on the code that is related to this functionality - so that new feature should be supported by this old one as well.
So my question is if is there any good practice on this, and what do you think what would be the best approach?
So I spent some time on thinking on the solution, and I think the best is to have an array of acceptable trigger variables in the model class. Then when the parameters are passed to the model on the controller level, then the loader function can be modified that it takes the trigger variables from the parameters and save it in the model's associative array variable that stores the trigger variables.
By default this array is empty, and it doesn't matter how much new variables are needed to be created, it will only contain the necessary ones when those are used.
Then of course the loader function needs to be modified in a way that it can filter out the non trigger variables as well as it is done for the regular fields, and there can be even a rule set of validation on the trigger variables if necessary.
So this solves the problem with overgrowing the object with unnecessary variables and the centralized validation part, because now the validation can be always done in the model instead of the controller.
And since the loader function is modified to store the trigger variables in the model's trigger variables array variable, the developer never has to remember that this functionality was created. Which is good, because in the future when he creates a new related function or end point that should handle object creation, he will not miss it to validate it against the old functionality, because the the loader function that he modified in the past like this will handle it for him.
It needs to be noted tho, that since the loader function doesn't differentiate between the parameters, and where to load them other then checking the names of the parameters with the filter functions, these parameter names should be identical from each other, otherwise a buggy functionality can be created accidentally. Like if you forget that a model attribute with the same name was used, then you can accidentally trigger an event that was programmed to be triggered if the trigger variable with the same name is present. However this can be solved by prefixing the trigger variables for example.
I am new to mocking and stubbing, but I think I have a circumstance where their use would be ideal.
In my application, when a user saves a Product, an after_save callback fires that creates Publication instances which cause the product data to be sent to certain 3rd parties via API.
I have a request spec for Product that tests my CRUD operations.
If I stub either the API methods or mock the Publication model, will those mocks/stubs be used in my spec even though they are actually called in the Product after_save callback? I'm confused about this point.
Update
I figured I would just do it like this:
Publication.any_instance.stub(:publist).and_return(true)
And do that at the beginning of my test. That way whatever instance is created would be handled. Is that how it works?
Yes that stub will do what it says and the publist method on any instance of the publication class will always return true.
Instead of putting it "at the top" though do something like.
context 'when there is a publist' do
Publication.any_instance.stub(:publist).and_return(true)
it 'should ...' do
...
end
end
then if required you can do tests without the stub, or tests where publist returns false in other context blocks and be nice and clear in the spec.
currently the JSONStore API provides a load() method that says in the documentation:
This function always stores whatever it gets back from the adapter. If
the data exists, it is duplicated in the collection". This means that
if you want to avoid duplicates by calling load() on an already
populated collection, you need to empty or drop the collection before.
But if you want to be able to keep the elements you already have in
the collection in case there is no more connectivity and your
application goes for offline mode, you also need to keep track of
these existing elements.
Since the API doesn't provide a "overwrite" option that would replace the existing elements in case the call to the adapter succeeds, I'm wondering what kind of logic should be put in place in order to manage both offline availability of data and capability to refresh at any time? It is not that obvious to manage all the failure cases by nesting the JS code due to the promises...
Thanks for your advices!
One approach to achieve this:
Use enhance to create your own load method (i.e. loadAndOverwrite). You should have access to the all the variables kept inside an JSONStore instance (collection name, adapter name, adapter load procedure name, etc. -- you will probably use those variables in the invokeProcedure step below).
Call push to make sure there are no local changes.
Call invokeProcedure to get data, all the variables you need should be provided in the context of enhance.
Find if the document already exists and then remove it. Use {push: false} so JSONStore won't track that change.
Use add to add the new/updated document. Use {push: false} so JSONStore won't track that change.
Alternatively, if the document exists you can use replace to update it.
Alternatively, you can use removeCollection and call load again to refresh the data.
There's an example that shows how to use all those API calls here.
Regarding promises, read this from InfoCenter and this from HTML5Rocks. Google can provide more information.
We’re using Ninject.Extensions.Interception (LinFu if it matters) to do a few things and I want to know if its possible to return a value form the method being intercepted.
EG
A Call is made into one of our repository methods
Our Interceptor gets the BeforeInvoke event, we use this to look into the ASP.NET Cache to see if there is any relevant data
- Return the relevant data (this would cause the method to return immediately and NOT execute the body of the method
- Or Allow the method to run as per normal
Extra points if in the AfterInvoke method we take a peek at the data being returned and add it to the cache.
Has anybody done something similar before?
From your question I assume that you derive from SimpleInterceptor. This will not allow to return imediately. Instead you have to implement the Iinterceptor interface. You can decide to call the intercepted method by calling the Proceed method on the invocation or not.