I'm creating some system, that can accept different incoming JSONs with ~40 fields inside. But as you may know, Play form mapping, can accept up to 18 field maximum.
So I thought it could be a good idea to split these incoming fields in to groups. For example Group1, Group2.. Group8. So I would accept only 8 parameters inside each group and these groups will have their own form mappings (where all fields are optional).
It was ok, until I came to the point: for some form mappings (for case classes) these fields must be mandatory.
For example, FormMapping1 must have Group1.field1, if not - form should give an validation error. But FormMapping2 can ignore Group1.field1, but Group2.field2 is mandatory for it.
But how should I create Group1 form mapping then?
As Forms do convert JSONs to objects, it's hard for me to imagine, how can I even do this validation. I mean, my case classes should have different constructor for each case I'm having mandatory field?
I hope I've described the situation well.
Would be great to hear from you some strategies of dealing with such issues. As I suppose my strategy isn't the best.
Thanks in advance!
P.S. currently I'm thinking about move away from Play Form validation to other.
Related
I'm using Google Data Studio to visualize results from various queries (from different tables within the same BigQuery-database).
For this reason, I created and use multiple data-sources-connectors. Each one of them has a SQL query included and makes use of an defined input parameter (which can be changed by report editors) - called "userid". It is the same id for all queries and resulting charts.
However, when I click "Manage URL parameters", I'm not allowed to use the same URL parameter for more than one data source (instead they are called ds0, ds1, ds2 etc - although they all end up being used as "userid").
If I add a data source under File - Report Settings, a new field "userid" appears, which I can alter - this will update ALL charts in the report with the very same userid (as expected). This works, but I do want to make use of an url which delivers an report with all updated queries depending on ONE userid.
Therefore, I guess I'm overseeing something - it should be possible to just use one query parameter to update the same "userid" for all queries in all data connectors? Or have I overlooked the possibility to fire multiple queries within one data source connector? Or is it expected to create a looong url full of redundant query parameters in this case?
I'm curious for your input!
Best regards :)
There does not seem to be any good solution for this.
For now the best workaround seems to be to just repeat the parameter multiple times -- it's ugly but it works. For example, use the URL parameter mapping screen to call the parameter u1, u2, etc., and then just pass all of them:
?params={"u1":"foo","u2":"foo"}
(URL encoded of course)
The ugliness is mostly for us developers: it violates our sense of DRY and clean code, and makes the URL much longer than it needs to be. However, most people don't care or know about the URL parameters so its irrelevant to them.
The bigger downside is that when the URL is distributed to clients (bookmarks, mobile apps), every time new data sources are added that require the same URL parameters, a new URL has to be distributed to clients for no good reason. A workaround for this is to build the URL dynamically via a simple redirector function.
This issue https://issuetracker.google.com/issues/180705297 is a feature request to implement this capability.
If you group the elements that you want to control with the same parameter (select and then shift G) then it will give you options to select the data source and the params box to apply to the group.
When we design Rest apis, it is said that use Path Variable when you need to identify a resource and Request Parameters when you need to do operations like sorting, filtering, searching, pagination. Let us take a scenario of Employee:
Employee has three fields like name, companyName, socialSecurityNo.
Now i want an Employee with a socialSecurityNo = ABC.
It seems fine to have endpoint with path variable like /employees/{socialSecurtityNo}, since we are identifying a resource.
Also it seems intuitive that we are filtering on the basis of socialSecurityNo and have an endpoint like /employees?socialSecurityNo=ABC
What will be the right way as i am confused and think that both apply.
It's a good question.
/employees?socialSecurityNo=ABC
is filtering all employees on socialSecurityNo. If socialSecurityNo is unique to an employee, there's no point in this endpoint existing and a client should use /employees/{socialSecurtityNo}.
There's nothing wrong with filtering on a unique field value (socialSecurtityNo) and if a client finds it easier to use this version (for whatever technical reason) then that's fine. There is no 'right' way. The ultimate reason APIs exist is to allow valuable work to be done by a client. Work with the client to allow that to happen but keep best practice in mind and know when the solution isn't the best but is the most practical in the situation.
I would expect to see:
/employees?surname=Smith
as this is filtering on a non unique field value and should return a collection of Employee objects.
The 'right' thing to do is keep the results consistent. If you have both ways of finding an employee, make sure the returned result is the same in each case.
In my Symfony 2 application I need to filter input before passing it on to validation [1], however, I can't seem to find any system within Symfony to do this.
The type of filtering I looking for is e.g. to be able to filter a dash out of a specific field before validating it. E.g. users can enter 123-123 but the only accepted value is 123123. Just as I can set up validation rules with constraints, I'm looking for something similar for filters.
[1] http://symfony.com/doc/current/book/validation.html
Nifr's answer is good but is missing of an important alternative that, if I understand correctly your question, seems to fit perfectly your needs.
You can use a hook that is pretty much an event listener: if something happens or is going to happen, it intercepts the event and redirect it to your function.
In this case, you need a PRE_BIND hook (is deprecated since 2.3 version, now it's called PRE_SUBMIT)
Read this if you need help about
Either write your own Validation Assert to filter and then proxy the other validators for this purpose ...
... or one or multiple Regex Asserts.
... or use a DataTransformer to transform/filter the input.
With the DataTransformer involved you could aswell consider creating a new FieldType which renders two inputs with a seperator like the date form-field does. ( if not not used with widget => single_text )
I need to build an application wherein the admin must be able to define forms for data entry. The data to be entered is unknown to me. But the system will need to be able to support all the possible form fields (minus hidden fields, I suppose). So text areas, text fields, radios (with ability to specify what the options are), checkboxes, etc. Also, it needs to be able to support line item entries (similar to EE’s Matrix plugin).
Obviously, I don’t want to try to build this from the ground up. Are there any libraries I can use in CI to make life easier for me?
If none exist, what are some database design patterns I should consider for such a problem?
The best database-design for this is the Entity-Attribute-Value Model. For use with a FORM, essentially your form is the ENTITY, the Attribute will have a type (used for deciding how input will be captured, and data interpreted). Make sure that you index properly.
Remember that you'll only need to data to change the form, don't read from this model everytime you need to show a form. Store a flat file (.json is handy) of the finished form and read that when displaying the form.
I am trying to do validations in struts 2 for my current project. I have to group my validation messages. For Eg: If there are 3 fields that are empty and there are 3 other fields whose format is not right, I need to get a msg like
"The following fields are required: field1, field2, field3
The format of the following fields are invalid: field4, field5, field6"
I tried providing a param to fieldError.
Eg:
< s : fielderror >
< s : param value="%{requiredstring}"/>
< / s : fielderror>
According to me this is like specifying "show all errors whose validator type is requiredstring". Please correct me if I am wrong.
But this will display the message "The following fields are required" each time for every field that is empty. I want it displayed only once.
Is there a way to do this cleanly in stuts2 using validation through xml? I donot want to do all the validations in a validate method.
Thanks
You are wrong; I have no idea why you thought that'd work, the docs don't imply that's possible.
Field errors are just that--errors for a specific field. If you need to group errors by arbitrary criteria, like the validation type, you'll need to implement that yourself.
There are a number of ways to do this, including writing a custom validation interceptor, providing validators that group errors in a different way, or simply gathering the appropriate messages in an action or validation method.
You could gather errors based on the message content, but IMO that would be brittle. If this is a cross-application issue, you're better off doing it a different way.
All that said, by presenting error messages in an order not necessarily reflective of the form, you're pushing more cognitive overhead onto the user: I don't want to see groups of messages telling me which fields share the same error, I want to see what's wrong with each field, in the same order the fields are presented on the form, preferably near the form field itself.