I'm going to be honest: this is a question I asked on the Django-Users mailinglist last week. Since I didn't get any replies there yet, I'm reposting it on Stack Overflow in the hope that it gets more attention here.
I want to create an app that makes it easy to do user friendly,
multiple / mass file upload in your own apps. With user friendly I
mean upload like Gmail, Flickr, ... where the user can select multiple
files at once in the browse file dialog. The files are then uploaded
sequentially or in parallel and a nice overview of the selected files
is shown on the page with a progress bar next to them. A 'Cancel'
upload button is also a possible option.
All that niceness is usually solved by using a Flash object. Complete
solutions are out there for the client side, like: SWFUpload
http://swfupload.org/ , FancyUpload http://digitarald.de/project/fancyupload/
, YUI 2 Uploader http://developer.yahoo.com/yui/uploader/ and probably
many more.
Ofcourse the trick is getting those solutions integrated in your
project. Especially in a framework like Django, double so if you want
it to be reusable.
So, I have a few ideas, but I'm neither an expert on Django nor on
Flash based upload solutions. I'll share my ideas here in the hope of
getting some feedback from more knowledgeable and experienced people.
(Or even just some 'I want this too!' replies :) )
You will notice that I make a few assumptions: this is to keep the
(initial) scope of the application under control. These assumptions
are of course debatable:
All right, my idea's so far:
If you want to mass upload multiple files, you are going to have a
model to contain each file in. I.e. the model will contain one
FileField or one ImageField.
Models with multiple (but ofcourse finite) amount of FileFields/
ImageFields are not in need of easy mass uploading imho: if you have a
model with 100 FileFields you are doing something wrong :)
Examples where you would want my envisioned kind of mass upload:
An app that has just one model 'Brochure' with a file field, a
title field (dynamically created from the filename) and a date_added
field.
A photo gallery app with models 'Gallery' and 'Photo'. You pick a
Gallery to add pictures to, upload the pictures and new Photo objects
are created and foreign keys set to the chosen Gallery.
It would be nice to be able to configure or extend the app for your
favorite Flash upload solution. We can pick one of the three above as
a default, but implement the app so that people can easily add
additional implementations (kinda like Django can use multiple
databases). Let it be agnostic to any particular client side solution.
If we need to pick one to start with, maybe pick the one with the
smallest footprint? (smallest download of client side stuff)
The Flash based solutions asynchronously (and either sequentially or
in parallel) POST the files to a url. I suggest that url to be local
to our generic app (so it's the same for every app where you use our
app in). That url will go to a view provided by our generic app.
The view will do the following: create a new model instance, add the
file, OPTIONALLY DO EXTRA STUFF and save the instance.
DO EXTRA STUFF is code that the app that uses our app wants to run.
It doesn't have to provide any extra code, if the model has just a
FileField/ImageField the standard view code will do the job.
But most app will want to do extra stuff I think, like filling in
the other fields: title, date_added, foreignkeys, manytomany, ...
I have not yet thought about a mechanism for DO EXTRA STUFF. Just
wrapping the generic app view came to mind, but that is not developer
friendly, since you would have to write your own url pattern and your
own view. Then you have to tell the Flash solutions to use a new url
etc...
I think something like signals could be used here?
Forms/Admin: I'm still very sketchy on how all this could best be
integrated in the Admin or generic Django forms/widgets/...
(and this is were my lack of Django experience shows):
In the case of the Gallery/Photo app:
You could provide a mass Photo upload widget on the Gallery detail
form. But what if the Gallery instance is not saved yet? The file
upload view won't be able to set the foreignkeys on the Photo
instances. I see that the auth app, when you create a user, first asks
for username and password and only then provides you with a bigger
form to fill in emailadres, pick roles etc. We could do something like
that.
In the case of an app with just one model:
How do you provide a form in the Django admin to do your mass
upload? You can't do it with the detail form of your model, that's
just for one model instance.
There's probably dozens more questions that need to be answered before
I can even start on this app. So please tell me what you think! Give
me input! What do you like? What not? What would you do different? Is
this idea solid? Where is it not?
Thank you!
I just released a simple app for this about a month ago: django-uploadify.
It's basically a Django template tag that acts as a wrapper for the very nifty Uploadify (requires jQuery). Using it is as simple as adding this to your template...
{% load uploadify_tags }{% multi_file_upload ‘/upload/complete/url/’ %}
The tag will fire events (1 per file) on both the client-side and server-side (Django signal) to indicate when an incoming file has been received.
For example, assuming you have a model 'Media' that handles all user-uploaded files...
def upload_received_handler(sender, data, **kwargs):
if file:
new_media = Media.objects.create(
file = data,
new_upload = True,
)
new_media.save()
upload_recieved.connect(upload_received_handler, dispatch_uid=‘whatever.upload_received’)
Check out the wiki for info on how to set it up and create the signal handlers (client/server).
About your conceptual implementation from above, here's a few points of consideration:
Having the app automatically create the "File Model" instance probably isn't as robust as people may already have their own models they're working with
If you want to implement any type of security or authentication, you need an open system and less of an 'auto-create' type
I really think signals/events are the way to handle this, and also handle the 'DO OTHER STUFF' part of what you mentioned.
My conclusion was that multi-upload can never really be a form widget in the sense that Django implements form widgets. 1 file will most likely be represented by 1 model instance (with some exceptions), which means that we end up with a situation where 1 widget can represent N model instances. However Django is setup so that a widget represents 1 value for 1 field in 1 instance. It just doesn't fit for the majority of use-cases to have it as a widget (hence why I went the template tag route).
Related
I'm an advanced beginner at django and python. I'm writing an app to handle registration and abstract submission for a conference, and I'm trying to use class-based views. Users get an emailed link that includes their registration code in the url. Starting at this url, users move through a series of views that collect all the necessary info.
The complication comes from the fact that users often stop half way through, and then want to complete the process several days or weeks later. This means that they might continue from the current page, or they might just click that original link. In addition, after several weeks they might have missed certain deadlines, so, e.g., they can no longer submit an abstract (but they can still register). Along the way, they have checked or unchecked various options that also influence the path they should take through the app.
My question is: where is the best place to put the logic that determines if the user is currently allowed to view that page, and if not, the best url to redirect them too? I thought I would create a custom view class that, e.g., overrides the dispatch method to include global checks (e.g., is conference registration open?), and then subclasses could add additional checks (e.g., has the user entered all the necessary info for her abstract?). The problem I ran into was that the checks were run in the wrong order (I want base class checks run first). I then started investigating custom view decorators or custom middleware. At this point I realized I could use some expert advice about which approach to take. (If it matters, I am not using the django authentication system.) Thanks in advance.
Maybe the form wizard could help you managing the viewing sequence.
In general django greybeards advocate keeping row-wise logic in Models, and table-wise logic in Managers, so it seems appropriate to keep complex view logic in a master view class.
The wizard class can help maintain the order of the views, but to resume an out-dated session you may need to do some model saves (which could get too complex very quickly) or some cookie handling.
In the past, when presented with a similar situation, I took the simplest route and separated user registration and the task that the user wants to perform (event registration). The user registers once but if they fluff up the event registration, they just have to log back in at a later date and do it again (their hassle - not yours!).
I have become a bit confused on the best way to move forward with something I'd like to achieve in Wordpress. My problem is partly workflow I think and knowing the correct way to do what I'd like to achieve but also there may be a few blanks on how to actually implement some of what I need to do. I have checked various online resources but they all are specific to what they are doing and I can't easily understand them to apply them in to the context of my own project, which is why I wanted to ask here. I'm sure my initial question will inevitably branch out to sub questions but here we go:
For my website I have created a custom post type called 'projects'. I have successfully set this up.
Then for each project I need to allow the following data to be entered:
Project Title
Project Description
Also post meta data that will display as a list on each project page (I'll need to display both the key and value on the page but only for those fields that contain data 'i.e. I don't want the list to show as Location: blank'):
Client Name:
Location:
Project Value:
Architect:
Engineer:
Site Area:
My main question is this, I need to show images for each project and allow the user to select a 'template' for each project post, this is because there are about 5 grid designs for layout of the images (1 main Image, 1 square image with two small images right side, 3 portrait image cols etc).
I thought the correct way would be to create a custom post type called projects, add write panels to allow easy input of data (I've yet to add image uploads as this will need to vary depending on the template selected and number of images required), at data input stage the user selects the preferred image layout/template and then uploads images for the containers that allow images (I’ll need to id each image upload to position it in the template with CSS, that was the plan).
Firstly, am I approaching this correctly? And secondly, how can I add functionality to the write panel I have created to allow users to a) select a 'Template' (bit like you can with pages but for my custom post type) and b) to add image upload fields which change depending on the template selected?
Finally, I would like to stay away from using plug-ins and try and achieve this myself through functions.php etc. This is to avoid problems later as plugins update or lose support etc.
Any help is appreciated, thank you.
This sort of question seems to come up a lot in regards to Wordpress (I answered essentially the same question the other day). I know you want to avoid plugins but this sounds like a job for Advanced Custom Fields.
You can create exactly the fields you need for your custom post type (including an image upload field), and then add them into the template the corresponds with your custom post type.
ACF does have a 'lite mode' which can be included directly in a theme. This way you needn't worry about updates nuking site functionality. Believe me you will save yourself a lot of time and energy this way.
It's admirable to try and do it with pure WP, but it's a maturing platform, it just doesn't lend itself to this sort of customization easily.
I'm building a small site framework for a set of sites that are likely to have quite a few unstructured pages - meaning they have:
Slightly different layouts per page
Lots of one-off text
None/very little generated content from models
I would like to allow clients to edit the content of these pages through my admin UI (I'm using Django for this project), but with the requirement that they are not exposed to the page HTML and are only able to edit parts of the page that I've specified as fields; for example:
Titles
A few blocks of text content
Perhaps some blocks of predefined image locations
PDF files that need embedding
Where these fields vary significantly between pages.
The layout, and what fields these pages require would be specified by the developer, so there's no need to dynamically generate much for this.
The 'best' idea I've had so far is to serialise these blocks of content once they've been edited by the user and store them in a 'Pages' table/model in my relational database, or just throw MongoDB or similar at it.
Conceptually, how would you implement such pages? As mentioned, I'm using Django so any implementation suggestions specific to Django are welcome, but general high-level ideas would be great too.
I would implement a ContentBlock model, which has .kind (header, text, image, pdf) and a .data, which would house the content (if text) or path to an uploaded pdf/image/etc. Presumably then you'd hardcode the pages with the appropriate blocks defined - I'd just use hardcoded slugs, eg, 'home-title', 'home-intro', 'about-title', 'about-text', 'about-right-photo', etc.
I would suggest not using Django's admin interface. It's much more suited to editing homogenous, non-business-logic models. I'd just add an edit view that renders the appropriate form fields for the blocks instead - html editor, file upload, etc. It's possible to do that in the django admin, but in my experience it's not worth the trouble - plus, if you do your own edit view, you can have it use the same base templates as the rest of the site, which IMO is a better user experience.
Here are a couple of apps which do that for you:
django-generic-flatblocks
django-boxes
Along with django-frontendadmin, it's super cool.
I'm looking at porting a custom-written PHP CMS into Django. One of the features the CMS currently has is an image upload function. I write an article, tag it with information, then choose a photo for it. If the system has any photos which have been added to articles with tags in common with the new one, it will suggest the photo for that article too. If there are no matches then a new image can be added.
In case this doesn't make sense, let's say I tag an article as Bruce Springsteen, The Beatles and Led Zeppelin. Next time I add an article with the tag The Beatles, it should suggest I use the image added for the first article.
What would be the best Django-applicable way to implement this? I've looked at the Photologue app and have integrated it, and I know it has tagging support (the problem here is that I'm using django-taggit, whereas Photologue supports django-tagging). One approach could be simply building it myself -- when a user uploads an article, I run a hook after they save it to associate the tags with the image. I'm just not sure how to then autosuggest an image in the admin tools based on that info.
Any ideas/approaches greatly appreciated.
This is almost certainly something you're going to have to build yourself. Django has a moderate number of libraries out there (that you've clearly already found). Unlike other solutions, it doesn't have a lot of things that get you 100% to your desired solution (whereas something like Drupal might get you 100% of the way there).
What you will probably need to do (at a high level) is something like this:
Create an AJAX view that takes the current tags as an argument and does a query on the existing posts to see what tags match and returns images from those posts.
Use jQuery/javascript on your view to call your AJAX view on the page as tags are added
Use jQuery to update a <div> on your page and show all the images that your view returned
Here is a similar example that might help get you started.
You might look into django-ajax as a helper library for your requests, but it definitely isn't necessary.
The hook between the your image module and any other django module can be implemented using django's contenttypes framework which also provides some useful instance methods for returning related/hooked objects.
I'm trying to write a simple CRM app in Django; partly as a learning exercise and partly for in-house use.
My schema is slightly complex, as rather that have a single Contact model (with a home phone, work phone, home email, etc.), I have stripped down Cntact model plus a Phone model, an Email model, etc., with a ForeignKey pointing back to a Contact. The point is to let Contacts have an arbitrary number of phone numbers, email addresses, etc. Simple, right?
I have some working views and templates for displaying the data - no issues there. And with only a very small amount of poking at admin.py I have a um...eight different TabularInlines set up, and the admin interface works to create and edit the data...but it's ugly and clunky to the point of unusability, and of course there's no conception of permissions or anything. I'm also not really a fan of having a completely different interface for displaying and searching through the data than for editing and adding contacts...I'd like as much as possible to be done inline, so that I can search for a name, look at the record, click "add note", have it popup a form, fill in the details, click submit, and be done, all with AJAXy goodness so there's no page reloads.
Question: Should I plug away at modifying the admin interface to try and make it usable for a user-facing app? And if so, can anyone point me to a good guide or example where someone has really changed the admin interface to make it work for user-facing CRUD operations?
Or should I just go ahead and write my own CRUD views? And if so, can anyone point me to a good guide or example where someone has written custom CRUD views that work with lots of ForeignKeys and inlines? Ideally I want a form that displays a single Contact, all his Email records, plus a blank form to add a new Email record, plus a button to add more blank forms, plus his Phone records, plus a blank form, and so on for all 8 of my associated models.
(Or am I thinking about this all wrong? Any advice appreciated.)
For our intranet, we use ModelAdmin subclasses (not mounted on the admin site via admin.site.register) for most of our C(R)UD views. By using custom templates for the views, it doesn't look like Django admin at all. What is very convenient though, is that it already handles all the validation/saving for us.
In general, I found admin-"hacking" quite useful to quickly write up C(R)UD views and usually with relatively small changes to your ModelAdmin subclass, you can make it work for your use case.
So I'd vote for use ModelAdmin, but not the one you use in admin, hook a different template and come up with some fancy CSS.
I successfully created a software on top of admin.
The admin hooks (these days) allow very fine-grained customizations, i.e. in general you only need to touch what you want to change.
The changes can go from a trivial cosmetic adjustment to a complete swap-out:
If you provide templates/admin/base.html your admin site can look any way you like. And of course, a navigation bar at the top could include links to some of your own views. Watch out not to hardcode URLs in your links, always reverse.
You can overload ModelAdmin's "change_view", "changelist_view" etc. and swap them for your own views. For example I replaced a default changelist and its simple filtering with a search interface that allows dynamic queries to be built, result columns to be customized by the user, and loading/saving of these searches. That didn't affect any of the other views of that ModelAdmin.
Overloading a ModelAdmin's "get_urls()" let's you rewrap existing admin urls to go to your own views. I did the latter for one model where I wanted the simple Add screen to be replaced by a totally customized Wizard (only leaning on ModelForm).
Don't forget the simplest approach, esp. regarding your "AJAXy goodness": Just define "css" and "js" in your ModelAdmin's Meta. Want to move an inline from the bottom to sit between third and fourth field, and that's not possible via parameters? A one-liner in jquery.
Check out "django-grappelli" for an example of how to improve admin look and feel.
What did you mean by "and of course there's no conception of permissions or anything"?