Wolfram Function Repository

Instant-use add-on functions for the Wolfram Language

Function Repository Resource:

 PersistentCloudForm

Source Notebook

Create forms with persistent values for cloud deployment

Contributed by: Jon McLoone

ResourceFunction["PersistentCloudForm"][form,store]

modifies form so that it has persistent user-specific values, storing values in CloudExpression[store].

Details and Options

The form must be either a FormPage or FormFunction.
The store must be either a String or a CloudExpression containing an Association with PartProtection→None.
The output is an APIFunction expression, which typically is deployed with CloudDeploy or CloudPublish for use in the cloud.
The output should not be deployed with Permissions→"Public" for long-term persistence or if sensitive information is being stored. Unauthenticated users will be tracked using a combination of IP address and browser details, giving a risk that another user could share the same values, and also resulting in loss of data if these details change.

Examples

Basic Examples (4) 

Deploy a simple GDPR (General Data Protection Regulation) permissions form:

In[1]:=
CloudDeploy[ ResourceFunction["PersistentCloudForm"][ FormFunction[{ "Name" -> "String", {"GDPRPermission", "I agree"} -> {"no", "yes"}}, AppearanceRules -> <| "Title" -> "Mailing preferences", "Description" -> "Please confirm that you give permission for us to send you email"|>, If[#GDPRPermission === "yes", "Thank you, we will keep in touch.", "OK, we won't mail you."] &], "myApp"], Permissions -> "Authenticated" -> "Execute"]
Out[1]=

When a user returns to the form, its state will reflect the last values that they submitted. These values can then be changed:

A CloudExpression is created to store the data:

In[2]:=
CloudExpression["myApp"][All]
Out[2]=

You can look up whether user "mcloone@wolfram.com" is currently giving their permission to be sent email:

In[3]:=
CloudExpression["myApp"]["mcloone@wolfram.com", "GDPRPermission"]
Out[3]=

Scope (1) 

Both FormPage and FormFunction are supported. Create a simple persistent GDPR permissions form that redirects the user on completion:

In[4]:=
CloudDeploy[ ResourceFunction["PersistentCloudForm"][ FormFunction[{ "Name" -> "String", {"GDPRPermission", "I agree"} -> {"no", "yes"}}, AppearanceRules -> <| "Title" -> "Mailing preferences", "Description" -> "PPPlease confirm that you give permission for us to send you email"|>, HTTPRedirect["http://wolfram.com"] &], "myApp"], Permissions -> "Authenticated" -> "Execute"]
Out[4]=

Properties and Relations (1) 

The data is stored in a CloudExpression. Changes to the values in the CloudExpression will be seen by the user when they visit form. For example, you can pre-populate the form for a user who has not used it yet:

In[5]:=
AssociateTo[CloudExpression["myApp"], "user@test.com" -> <|"Name" -> "John Doe", "GDPRPermission" -> "no"|>];

Publisher

Jon McLoone

Version History

  • 1.0.0 – 06 August 2020

Related Resources

License Information