Flask POST request and javascript - flask

Is it possible to POST data with flask_sqlalchemy and prevent a page reload?
I have a webpage with a form. The form only appears after a function, activated by an onclick event, is run. I want my user to be able to submit information using the form, and see the form only empty and the rest of the page remain unchanged.
I have already tried return '', 204 but this does not fix the issue.

Use Javascript or jQuery:
Javascript example:
function resetFormPause() {
myVar = setTimeout(resetForm, 250);
}
function resetForm() {
document.getElementById('form').reset();
}
Add onclick='resetFormPause()' to your submit button and use <form id='form'>.
We use setTimeout() to allow the data to be sent. If we merely add the resetForm() function, we will delete the data that we want to send. If we have small text to send, 250ms is plenty of time. If we have larger data, then we use the same idea, but we have to (a) allow more time, or (b) use an event to trigger the execution of resetForm().

Related

Django - Create new object in Form, update select box and save it

I think what I'm trying to achieve is not hard, but I have no clue how to do it hehehehe !
Basically what I need is the feature that we have in Django Admin, when you are creating a new object, if you have a Foreign Key, you can add new data (opening a pop-up), save it and then the select box updates automatically.
What I have is this form:
I know that would be easy to do it with some Javascript, but my point is, Django has some rules, and as far I know, I can't add new data to a form already created, right? Otherwise Django won't validate this form. How could I achieve this?
PS: "Local" is the select box where I want to add new data. The user should be able to create a new Local on this page, instead of going to another page to do it. Thanks :)
Here your question:
I can't add new data to a form already created, right? Otherwise Django won't validate this form. How could I achieve this?
Then the answer:
you are right, django will check values match form value rules. But:
realize that your main form is invoked for twice: on GET and on POST. Between both form executions you make changes on database values trhough your new form. That means that in second main form invocation the value added to database is available:
field1 = forms.ModelChoiceField(queryset= ***1*** )
***1***: on second invocation new value is already available on field1.
Then, you don't should to be afraid about this subject, the new value will be available on form on your main form POST request.
Nothing wrong with updating the value using javascript as long the key in your new combo box has the right key in the database then it should be ok.
Call this function after you saved the last entry.
function refreshLocal(){
$.get(window.location.href, '', function(html){
// change the id to the local combox's id
var serverLocalDropBox = $(html).find('#id_local');
if (serverLocalDropBox.length){
$('#id_local').replaceWith(serverLocalDropBox);
}
})
}
If you don't want to use javascript solution, you can post the form with refresh flag and on the server side if you see that flag just don't validate and return the form as is. Since you have a new entry in the foreignkey it will automatically update the queryset to include the new entry.
function serverRefreshLocal(){
var $form = $('#your_form_id');
$form.append('<input type="hidden" name="refresh" value="true" />');
// you can use ajax submit and ajax refresh here if you don't want to leave the page
$form.submit();
}
// Server Side
def your_form_post_view(request):
if request.POST.get('refresh', 'false') == 'true':
# initial is the trick to save user input
your_form = YourForm(initial=request.POST)
context = {
'form': your_form,
}
return render(request, 'your_template.html', context)
# your view code goes here

Django - doing an internal view post

I have a Django app that has two view requests. The first request ("add_item") is the add request, which does some validation and then ultimately adds an item to a user's queue. The second request hits a user's facebook feed, iterates through the posts, and adds some of them to their queue. Ideally, I don't want to replicate the logic for the add in that second request. I'd rather just call the first request within the second request's loop.
I can't figure out how to do this and still pass in the user's context in the request. Does anyone have an example of how to do this? I tried passing in the POST data and the user context that the first request requires:
request = { "POST": { "queue_id": 1, "data": "some_data_to_add" }, "user": request.user }
add_item(request)
However, request.user doesn't get serialized properly. I'm also pretty sure I can't just pass the POST data that way, I'm sure it also needs to be serialized somehow. In general, I think this is not the standard way to do something like this.
Create a separate a view which perform the task of adding items into the queue and call that function from both first and second view.
for example:
def adding_items(<necessary params>):
item add logic here.
def first_view(request):
# call adding items to update queue.
adding_items( <params> )
def second_view(request):
# call adding items to update queue.
adding_items( <params> )
Thats it :)

Sitecore Web Forms for Marketers and DMS - not recording campaigns, goals and dropout info

In WFFM there is an option so that, when someone abandons the form, any data that was entered in the form itself is recorded and should be accessible via the Dropout Report.
I have a WFFM for which I have turned on Analytics and turned on the dropout feature. Unfortunately I don't see any data being recorded in the DB and the Dropout Report is visible, but empty.
I see from the javascript code included in the WFFM folder that a series of AJAX calls are supposed to save the fields on blur events -- with calls to /sitecore modules/web/Web Forms for Marketers/Tracking.aspx
I tried debugging the Javascript code, but the method supposed to post the info to /sitecore modules/web/Web Forms for Marketers/Tracking.aspx is never being called. Can you think of any reasons for this code not to work? Also, does anyone know which table this information is supposed to be recorded? Is it the fields table in the WFFM DB?
Finally, even though I have turned on analytics on this particular WFFM form and I have associated a campaign and a goal to the submission of the form, none of these is being recorded. I see that the data entered in the form is stored successfully and is displaying in the Data Report, but no info about the Campaign nor the Goal are recorded in the DB.
I even checked manually directly in the DMS DB running:
select top 10
p.DateTime, p.UrlText, cp.CampaignName
,i.Url, vi.VisitId
from pages p
inner join ItemUrls i on p.ItemId = i.ItemId
inner join Visits vi on vi.VisitId = p.VisitId
inner join GeoIps g on vi.Ip = g.Ip
left join Campaigns cp on cp.CampaignId = vi.CampaignId
order by p.DateTime desc
This one shows that the page where the form is rendered is being hit, but no campaign is associated to the visit.
Then I tried the following:
select pe.datetime, ped.Name, pg.UrlText from PageEvents pe
inner join PageEventDefinitions ped on ped.PageEventDefinitionId = pe.PageEventDefinitionId
inner join Pages pg on pg.PageId = pe.PageId
order by pe.DateTime desc
But I don't see any entry for this particular campaign nor for the goal (while I see entries for other campaigns and goals associated to non-WFFM Sitecore items)
Any advice would be greatly appreciated!
Thanks,
Francesco
EDIT
The sc.webform.js file contains this method:
_create: function () {
var self = this,
options = this.options;
if (options.tracking) {
this.element.find("input[type!='submit'], select, textarea")
.bind('focus', function (e) { self.onFocusField(e, this) })
.bind('blur change', function (e) { self.onBlurField(e, this) });
this.element.find("select")
.change(function () { $scw.webform.controls.updateAnalyticsListValue(this) });
this.element.find("input[type='checkbox'], input[type='radio']")
.click(function () { $scw.webform.controls.updateAnalyticsListValue(this) });
}
this.element.find(".scfDatePickerTextBox").each(function () { $scw.webform.controls.datePicker(this) });
},
This is supposed to be called by the form on sc.webform widget initialization. It should bind the focus and blur change events for all input fields, drop downs and text areas. Unfortunately, when I tried to put a break point inside this method, it never gets called.
SECOND EDIT
Interesting. I figured out that the whole thing should start from this line of Javascript code embedded in the page that contains the WFFM form:
<script type="text/javascript">
$scwhead.ready(function() {
$scw('#form_A8BF483419174F97A2830E12CBCF7E4F').webform({formId: "{A8BF4834-1917-4F97-A283-0E12CBCF7E4F}",pageId: "{21C24144-B964-4FBA-8388-D9B90EBBC17C}",eventCountId: "pagecolumns_0_columncontent_0_bottomrow_0_form_A8BF483419174F97A2830E12CBCF7E4F_form_A8BF483419174F97A2830E12CBCF7E4F_eventcount",tracking: true})
});
</script>
Once I put a break point here, I was finally able to trace into the _create method of the jQuery.UI widget defined in sc.webform.js. The code that calls _create is actually inside the jQuery.UI library. Kinda makes sense, right?
Finally, the code inside _create is executed, the blur events are bound to the TrackEvents method, also defined within the widget:
_trackEvents: function(events) {
$scw.ajax({
type: 'POST',
url: "/sitecore modules/web/Web Forms for Marketers/Tracking.aspx" + location.search,
data: {track: JSON.stringify(events)},
dataType: 'json'
});
What doesn't make sense is that now, even though I can finally see trackEvents being called whenever I tab from field to field in the WFFM form (why wasn't working before it's a mistery to me), I don't see any data recorded in the WFFM DB. I even tried a quick query in the DB:
select f.Timestamp, f.StorageName, fi.Value, fi.FieldName
from Form f
inner join Field fi on f.Id = fi.FormId
order by f.Timestamp desc, FieldName
Does anybody know where is Tracking.aspx supposed to save the captured field informations?
This may be silly to ask, but did you configure the data source correctly for your WFFM? I mean, obviously, you're using WFFM..but is it set to use SQL or is it using the "file" that WFFM uses by default as it's database.
like this to use SQL:
<!-- MSSQL-->
<formsDataProvider type="Sitecore.Forms.Data.DataProviders.WFMDataProvider,Sitecore.Forms.Core">
<param desc="connection string">Database=Sitecore_WebForms;Data Source=xxx;user id=xxx;password=xxx;Connect Timeout=30</param>
</formsDataProvider>
<!-- SQLite -->
<!--<formsDataProvider type="Sitecore.Forms.Data.DataProviders.SQLite.SQLiteWFMDataProvider,Sitecore.Forms.Core">
<param desc="connection string">Data Source=/data/sitecore_webforms.db;version=3;BinaryGUID=true</param>
</formsDataProvider>-->
If you don't configure that correctly, I'm wondering if somehow data is being recorded in one place but not another? Also, another question I have is to ask if this is a dev environment, are you running webforms in live mode? It just seems to me like this is a configuration issue.
We are experiencing the exact same problem on 6.5 update 6 and WFFM 2.3.3 rev. 111209. We can see the asynchronous calls to the server including the probably well formed json object containing the correct event.
Example:
track:[{"fieldId":"{E0A0BCDD-85E1-4D8D-9E76-5ABD240423C9}","type":"Field Completed","value":"test","formId":"{0F3B57C1-1B6A-43B9-A5A6-2E958C168B31}","pageId":"{025AFF68-62B9-42CE-B49F-0C36311E1976}","ticks":16}]
We don't see any of the dropouts arrive in the database, though...
Have you made sure your campaigns and goals have been deployed? If you have switched databases they may not be. To redeploy do this:
For each Goal in System -> Marketing Center -> Goals
Change the workflow state to draft
Save
Then in the review ribbon click deploy.
This will create an entry in the pageeventdefinition table and allow
you to query.
Don't forget to do the same for campaigns.

Django - show loading message during long processing

How can I show a please wait loading message from a django view?
I have a Django view that takes significant time to perform calculations on a large dataset.
While the process loads, I would like to present the user with a feedback message e.g.: spinning loading animated gif or similar.
After trying the two different approaches suggested by Brandon and Murat, Brandon's suggestion proved the most successful.
Create a wrapper template that includes the javascript from http://djangosnippets.org/snippets/679/. The javascript has been modified: (i) to work without a form (ii) to hide the progress bar / display results when a 'done' flag is returned (iii) with the JSON update url pointing to the view described below
Move the slow loading function to a thread. This thread will be passed a cache key and will be responsible for updating the cache with progress status and then its results. The thread renders the original template as a string and saves it to the cache.
Create a view based on upload_progress from http://djangosnippets.org/snippets/678/ modified to (i) instead render the original wrapper template if progress_id='' (ii) generate the cache_key, check if a cache already exists and if not start a new thread (iii) monitor the progress of the thread and when done, pass the results to the wrapper template
The wrapper template displays the results via document.getElementById('main').innerHTML=data.result
(* looking at whether step 4 might be better implemented via a redirect as the rendered template contains javascript that is not currently run by document.getElementById('main').innerHTML=data.result)
Another thing you could do is add a javascript function that displays a loading image before it actually calls the Django View.
function showLoaderOnClick(url) {
showLoader();
window.location=url;
}
function showLoader(){
$('body').append('<div style="" id="loadingDiv"><div class="loader">Loading...</div></div>');
}
And then in your template you can do:
This will take some time...
Here's a quick default loadingDiv : https://stackoverflow.com/a/41730965/13476073
Note that this requires jQuery.
a more straightforward approach is to generate a wait page with your gif etc. and then use the javascript
window.location.href = 'insert results view here';
to switch to the results view which starts your lengthy calculation. The page wont change until the calculation is finished. When it finishes, then the results page will be rendered.
Here's an oldie, but might get you going in the right direction: http://djangosnippets.org/snippets/679/
A workaround that I chose was to use beforunload and unload events to show the loading image. This can be used with or without window.load. In my case, it's the view that is taking a great amount of time and not the page loading, hence I am not using window.load (because it's already a lot of time by the time window.load comes into picture, and at that point of time, I do not need the loading icon to be shown anymore).
The downside is that there is a false message that goes out to the user that the page is loading even when when the request has not even reached the server or it's taking much time. Also, it doesn't work for requests coming from outside my website. But I'm living with this for now.
Update: Sorry for not adding code snippet earlier, thanks #blockhead. The following is a quick and dirty mix of normal JS and JQuery that I have in the master template.
Update 2: I later moved to making my view(s) lightweight which send the crucial part of the page quickly, and then using ajax to get the remaining content while showing the loading icon. It needed quite some work, but the end result is worth it.
window.onload=function(){
$("#load-icon").hide(); // I needed the loading icon to hide once the page loads
}
var onBeforeUnLoadEvent = false;
window.onunload = window.onbeforeunload= function(){
if(!onBeforeUnLoadEvent){ // for avoiding dual calls in browsers that support both events
onBeforeUnLoadEvent = true;
$("#load-icon").show();
setTimeout(function(){
$("#load-icon").hide();},5000); // hiding the loading icon in any case after
// 5 seconds (remove if you do not want it)
}
};
P.S. I cannot comment yet hence posted this as an answer.
Iterating HttpResponse
https://stackoverflow.com/a/1371061/198062
Edit:
I found an example to sending big files with django: http://djangosnippets.org/snippets/365/ Then I look at FileWrapper class(django.core.servers.basehttp):
class FileWrapper(object):
"""Wrapper to convert file-like objects to iterables"""
def __init__(self, filelike, blksize=8192):
self.filelike = filelike
self.blksize = blksize
if hasattr(filelike,'close'):
self.close = filelike.close
def __getitem__(self,key):
data = self.filelike.read(self.blksize)
if data:
return data
raise IndexError
def __iter__(self):
return self
def next(self):
data = self.filelike.read(self.blksize)
if data:
return data
raise StopIteration
I think we can make a iterable class like this
class FlushContent(object):
def __init__(self):
# some initialization code
def __getitem__(self,key):
# send a part of html
def __iter__(self):
return self
def next(self):
# do some work
# return some html code
if finished:
raise StopIteration
then in views.py
def long_work(request):
flushcontent = FlushContent()
return HttpResponse(flushcontent)
Edit:
Example code, still not working:
class FlushContent(object):
def __init__(self):
self.stop_index=2
self.index=0
def __getitem__(self,key):
pass
def __iter__(self):
return self
def next(self):
if self.index==0:
html="loading"
elif self.index==1:
import time
time.sleep(5)
html="finished loading"
self.index+=1
if self.index>self.stop_index:
raise StopIteration
return html
Here is another explanation on how to get a loading message for long loading Django views
Views that do a lot of processing (e.g. complex queries with many objects, accessing 3rd party APIs) can take quite some time before the page is loaded and shown to the user in the browser. What happens is that all that processing is done on the server and Django is not able to serve the page before it is completed.
The only way to show a show a loading message (e.g. a spinner gif) during the processing is to break up the current view into two views:
First view renders the page with no processing and with the loading message
The page includes a AJAX call to the 2nd view that does the actual processing. The result of the processing is displayed on the page once its done with AJAX / JavaScript

Ajax to login users...callback function not working

This is my second foray into Ajax and I'm not quite sure how to pull this off.
So I have a modal window that opens when an anonymous user attempts to perform a certain task. The window contains a user signup form that I then $.post to my Django login view. If username/password are valid, user is logged in an status code of 1 is returned as the response. IF not, a status of 0 is returned.
When I try to do it outside of js, it works. However, within my script, it fails. I think that it has to do with the response content_type and how I'm interpreting it. I'm not sure.
def login_async(request):
if request.method=='POST' and len(request.POST['username'])<20 and len(request.POST['password'])<20:
username=request.POST.get('username', '') #probably need to script tags here
password=request.POST.get('password', '')
user=auth.authenticate(username=username, password=password)
if user is not None:
auth.login(request,user)
status=1
response=HttpResponse()
response['Content_Type']="text/html"
response.write(status)
return response
else:
status=0
response=HttpResponse()
response['Content_Type']="text/html"
response.write(status)
return response
$('input#login').click(function(event){
$.post("/login_async/", {username:$('input[name=username]').val(), password:$('input[name=password]').val()}, //could also use $(this).serialize() here to capture all form inputs
function(data){
if(data==1){
$('#login').dialog("close");
}
});
});
What's the problem here? I initially tried to return the response as JSON but I couldn't figure out how to make serialize.serializers("json",status) work. I kept getting an error.
One last question...
If I get a valid status (user is signed in), that will influence the behavior of modal windows on the page. The modal windows open based on logged in status. If a user is signed in, one set of windows open on a click event, and vice versa. This toggle is dependent on Django context {% user.is_authenticated %}.
That context renders only once right, on page load? Can I do anything to communicate the status change to the modal windows that's secure from easy hacks?
It should be Content-Type. If that doesn't fix your problem, try adding a dataType parameter at the end of the $.post call.
$.post("/login_async/", {}, function(data){
// fancy stuff
}, "html");
Yeah I thought it over more and realized that I should just unbind the existing click event handlers on the modal windows and then bind new event handlers depending on the ajax response.
I love programming