I am using a controller implementation that is extending the Spring MVC
AbstractWizardFormController
This wizard controller will consist of 4 pages. The first 2 pages are used to collect information. The third page will show results based on what information is submitted on page 1 and 2.
So to be a little more specific
Page 1 the user will select a state and some other information
Page 2 the user will enter more information such as contact information
Page 3 will display information dependent on the information collected in first two pages
There is more pages after this, but they do not pertain, so if the first think you are thinking of is using onSubmit(), then it wont work because it is not the end of the controller life.
I need to collect all the data from the first two pages, and then run a db query and return it to the third page. where and how is the best way to do this, do I run the query in reference data when returning to the third page?
You can use postProcessPage method. Its API is clear
Post-process the given page after binding and validation, potentially updating its command object. The passed-in request might contain special parameters sent by the page.
Related
The project is simple, and it has to do with formula 1 statistics. The UI looks a lot like a game menu. Going from "option" to "option" in the UI you end up in an "endpoint" page where the user can see the statistics of his like. It's tree structure where every "option" is a separate view on my project.
The user click "Race standings" to load a page. The user click a year on a form to see next page. The user click a race of that year then redirects to "race result" page. The logic for doing this is to create a nice UI so the user would like to spend time on the site and navigate through the pages.
I POST data from my view's forms to a controller's function. This function fetch the data from the database using my models and the post parameters, do the logic and return('thatView', compact('array' , 'array2', 'etc). php and javascript on the views manipulates the organized arrays fitting them into html. Arrays contains text data, for example array 1 could be the data of a race-result table.
The way my project is structure is very amateur. No patterns, no architecture, no anything good. Using directly the raceresult domain on the browser will result error. The needed parameters are missing as they cannot be set from the domain, it needs the previous page to post the data.
How could i structure my project better? What patterns could i use?
This is a basic overview you can follow:
App
-- Repositories
-- Services
Route > Controller > Service > Repository
Controller's method calls Service method. Here you put your business rules. If there as need of calling database, use repositories to do that.
It's clear for you?
Current Situation
I have a Web App with an example URL that looks like this
https://script.google.com/a/domain.com/macros/s/Adlksjflf09_LEg8kdlf9/exec?ID=1
This Web App has a doGet(e) function that redirects it to a Google Form URL. Using the example above, it would look like this
https://docs.google.com/forms/d/e/1FAIpQLSfi8jWUK2N4y03N4YYJ9p8Cyr2x06b1C6WgS_TcV98WM_ACtQ/viewform?ID=1
This ID field does not pre-fill any of the questions in the Google Form. Essentially, it's meant to hold information.
When a user submits a form response, I'm combining information from the query parameters as well as the form response and sending it as a payload to a webhook URL.
How I do that is by using CacheService. When a user opens the first URL, the doGet(e) function stores the e.queryString as a Hash in the cache. Then when a user submits the form, I can get the information from the cache and combine it with the formResponse.
The issue I have now is related to concurrency. There will be a case where more than 1 user has opened the first URL. This results in Hash['queryString'] to be overwritten in the cache which is not what I want.
Actual Question
Is there a way to take query parameters from an onFormSubmit from a form and combine it with the form response without using CacheService since my current solution does not support concurrency?
From my understanding, the onFormSubmit trigger doesn't have an e (event variable) for me to do something like a e.queryString to get the query parameters. I may be wrong, need someone to confirm.
OR
Is it possible to cache information in such a way that I can keep track of whose query string is whose and then pull the appropriate information when submitting the form.
I am new to RESTful URLs and I have a general question. Let's say I have a URL that I use to retrieve student records: somesite.com/students/123 which retrieves the details for the student with ID 123.
I then do the following to load an empty form for adding students: somesite.com/students/0 where zero indicates that I want to display an empty student detail form (or somesite.com/students/new).
The question I have is that after I add a student record I get back a new Id. However, if I add the record using AJAX without submitting and refreshing the page, my URL still shows somesite.com/students/0. If a user clicks refresh then the empty form is displayed again rather than the new student record.
How should that be handled?
It's not like your server can't respond to AJAX requests, right?
All you need to do is send back the newly generated ID, and then:
Use window.location = 'new_url' to redirect the user
Or even better, use history.pushState() (if available) to change the URL without any redirection (and reloading) happening at all
One thing that seems off, though, is the use of GET page/students/0 to get an "empty record", or, as I understand it, a "template" for new records. I don't think that's how RESTful services work, but then again, I'm not an expert in REST services.
I have read a lot of answers relating to how to dynamically add forms to an model formset in Django and can successfully implement that. However, I would now like to submit the formset with AJAX. This is mostly working now but I have an issue that I can't find a solution to in any other answer:
If you dynamically add a form to the formset, you give it a new form id number that is one larger than the maximum the form currently has and you also increment the management TOTAL_FORMS count by one. The newly added form then saves successfully as a new object.
I am trying to submit by AJAX so the user can continue editing without having the page refresh. The formset saves fine but any dynamically added forms are now existing objects. To account for this I need to increment the INITIAL_FORMS count on the management form when the save is successful. Easy enough. However, I've also realised I need to give the newly created objects an ID since they now exist in the database.
How can I get my view to tell me the ID of the new objects in its response to the AJAX call? Or is there a better way of looking at this?
Django forms and formsets are intended for classic browser-based posting of data. Though they can definitely be made to work with Javascript, the more you want to part from the normal behavior, the more complex it gets.
Depending on your requirements, you might start thinking about dropping it and switch to Javascript + REST endpoint. Of course, if you need progressive enhancements and you are required to have it work without javascript, that's not an option.
In any case, you want to have a customized view for posting from JS, so that you can get the result back and parse it easily in your AJAX handler. Probably some JSON.
There are several approaches you could take.
Have your AJAX send data to a different URL. This is pertinent if you have an API or are planning to build one at some point. So your form, when submitted normally, will do its old-style processing but your AJAX will talk to the API endpoint instead.
For instance, your form send to https://example.com/myform, but your Javascript code talks to REST api at https://example.com/api/v1/mymodel/ (sending PUT, POST and DELETE requests as appropriate).
Or if you don't have an API and building one seems overkill, you may just alter your view so it formats its output differently depending on whether the data is being submitted in the regular way or using AJAX.
You'd go about it like this:
class MyFormView(.....):
def render_to_response(self, context, **kwargs):
if self.request.is_ajax():
return self.render_to_json(context, **kwargs)
return super().render_to_response(context, **kwargs)
def render_to_json(context, **kwargs):
data = {
# see below!
}
return HttpResponse(
content=json.dumps(data).encode('ascii'),
content_type='application/json',
)
This is just an outline. You need to ensure is_ajax will detect it properly (see django doc). And you need to properly build data from context: extract the things you want to send back to your JS code and put them in the dict.
You will find it's manageable if you just do this for one, maybe two views in your project, but very quickly you'll want to have a small API instead, especially given how easy it is to build one with packages such as Django REST framework.
In your view, where you save the object, AFTER the save, the object.id will contain the new id for the object, which you can return via json or however you want in your ajax response, and then yes you will need to fill that into the formset row so that it will be submitted the next time.
One thing you have to watch out for is that django expects all existing rows to be at the top of the formset, and any new rows to be at the bottom. Otherwise, the formset save will complain about missing id's. So if you're doing any kind of sorting in your javascript, you can't do that.. unless you do quite a bit of fixing of all the field names etc in the formset. The formset code uses the numbers in the management form to determine which rows to insert and which rows to update, it does not do it on the basis of whether or not an id is present. Unfortunately...
I am trying to code my first codeigniter project. I have a login controller which basically filters the data inputed and calls a model function that checks if the user is found in the database.
What I am trying to do is reuse this controller on the index page. So basically I want to be able to do user login on the index page or on the normal controller page (index.php/login/) without code duplication.
I'm sure there is an easy way to do this, but I'm not sure what the best solution is. Make it a library?
Thanks!
For this I would simply make the form in your view post to the login controller.
As a more generic way to share code and logic throughout your application, take a look at this article:
CodeIgniter Base Classes: Keeping it DRY
You basically give each of your controllers a "type". Being logged in could be a criteria of one of your base controllers, which saves you trying to directly access any of your controllers which is bad mojo.
You can try creating a form on the index page and submit it to index.php/login/. This way you won't need two entry points.
Just do the same as you have done for the login View, specify the same action attribute of the form to the index View, and it will be sent to the same login controller with no need to create the two login controllers. You might want to append a query string in the action attribute of the form to distinguish from which View the request has come.