Need Application Advice - django

I have a django application that contains customer and product information. It is simple but gets the job done. My customer wants the capability to send form letters and news letters and create them from within my app. From a text editing perspective, I understand how simple form letters work by replacing certain blocks of text with queries from the database. But my customer wants fliers with complex graphics and column-based layouts. There are some very mature products out there that I can't come close (nor want to) compete with. He talked about building and editing these pages from within my app. This seems a bridge too far but I don't know if its even possible to build that into a django app.
I have no idea how to approach this and it seems very complicated. But, before say no, I want to explore the available technology and level of effort entailed. Are there open source packages that can help? How could one integrate this capability into a django-based web application? and how hard is it? For a part-time intermediate developer how long would it take?

I'd farm the layout off to something like TeX Live. From there you can generate a PDF and attach it to an email message. Don't let "... a popular means by which to typeset complex mathematical formulae" throw you, TeX is useful for more than that.

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Is it an efficient method to use a framework to code a single interactive webpage in python?

This is an open source contributor project for Wikidata's Chronic Pain project.
I would like to create a webpage that :
Have inputboxes where the user select several wikipedia page titles (with suggestions)
Can also take these parameters via the URL
Get items metadata from Wikidata.
Makes a SPARQL request to gather scholarly articles.
Render data from Wikidata and Wikipedia, linking to various wiki pages.
The webpage will be hosted on Wikimedia fundation server. I have access to a linux container as well as a Jupyter Notebook (not sure this one is suitable for this project). It has to be coded in Python 3 since I will use Pywikibot framework to interact with Wikidata.
I'm new to programming so that I don't really know what is the best approach. I heard that it was difficult to code webpages in Python without using a framework like Django. However this page is very simple so that it may not be the most efficient to deploy Django for this ?
NB : your question is bordering on "primarily opinion based" (which doesn't mean it's a bad question by itself but that answers might be more, well, opinions than hard facts).
This being said, "a single interactive page" doesn't mean the server code behind is just loading a static html file and sending it to the client. For example, the main UI part of our product is, technically speaking, "a single interactive page", but this "single" page is full react app and is backed by a dedicated API with a dozen entry points, which the dispatch to a whole load of backend code including database access, celery tasks etc. It would of course be technically possible to code all this with only pure wsgi or even plain old cgi code, but well, it could also be possible to write it directly in C or even assembly and no one would ever consider this a viable solution.
To make a long story short: do not even waste your time trying to code this project with plain wsgi (and let's not talk cgi), you will end up reinventing the squared wheel and everyone will hate you for this (stakeholders because you'll never deliver a robust, working product in due time and budget, and other devs because they'll now have to port the whole darn thing to a stable, mature and maintained framework). Now if Django appears to be overkill for this project there are much lighter frameworks like flask. Actually both are the "industry standard" and safe choices.

Django vs. Grok / Zope3 vs. Pylons

I am a computer programmer by training but have been away from web development for a while. I am doing a little bit of background research on various Python web development frameworks. I understand that Django, Grok / Zope 3, and Pylons are all good solid frameworks, but have little in the way of background working with them. Can someone explain to me the difference in approach of the each of the frameworks, and where one shines when compared to the others?
My specific use case is in building a web application that will recommend products to users based on a variety of user supplied information. Thus, it will take a fair bit of user input in the shape of a basic profile, product preferences, attempt to establish social relationships between users. It will also need to support staff uploading products into the system with labeled features that can be then matched to users.
On the last point, would parts of Plone help with providing an interface for non-tech people to upload products and descriptions of the products? Are piece of Plone easy to borrow? Seems like I shouldn't have to reinvent the wheel in terms of having a way for people to upload items for sale / recommendation along with some metadata to describe the items. Thanks for the help.
Based on your background and requirements, I'd advise you to go with something like http://pinaxproject.com/ which is based on Django.
Pyramid (the successor to Pylons) is a very low-level framework and you need to either choose the libraries or write all your application code yourself. For someone experienced this makes sense and gives you full control over your code. But it is a bit of a hurdle if you start from scratch and aren't familiar with the available libraries.
Django and Grok are both high level frameworks, with Django being the more popular choice. If you aren't familiar yet with using object databases or URL traversal, Grok is more time consuming to learn.
Plone is not suited for your use-case. It's a content management system and not a general web framework. Very little of the libraries it uses can be reused in a different context, certainly none of its UI. If you want to provide an engaging user experience with personalized content, Plone isn't for you - that's not what its been build to handle.
Disclaimer: I'm a release manager for Plone and Zope 2 / Zope Toolkit and have used Pyramid but not Django.
Dolmen project is a CMS built on top of Grok. Is very simple, but there are very few that use it. If you go with Grok, you could be able to reuse the GUI.
But As Hanno said, Grok is more time-consuming to learn than Django. Also Django has far more users than Grok.
The advantage of using Grok is that you can profit from Zope Component Architecture almost without writing ZCML and using decorators instead.
With Pyramid/Pylons you get a very simple framework and nothing else. It is a decoupled framework, so you are free to use whatever templating enginge you want (Mako, Genshi, Jinja, Cheetah), you are free to choose sqlalchemy, zodb, mongoDb, etc., and you are also free to choose the url mapping scheme (traversal vs. django-style mapping or a combination of both). You can also use ZCA here if you want. For starters this might become quite confusing or verbose.
Django is a kind of monolithic framework that gives you one way to do stuff. That's why it's easy to learn and a very good option. But, in my experience, you sometimes get to a point where you want to deviate from Django standards and it simply cannot be done without patching a bunch of stuff.
And, as for Zope3, I'd recommend you to download a copy of BlueBream and se how it does for you.
As a Plone user I can say that creating Content Objects in Plone is difficult. There is not much documentation on how to do it and it is complicated. Some recommend using UML and specialized Plone products to make it easier but that introduces yet another dependency.
I mention the problem with content objects because your "products" (not the same as a Plone product) would probably be represented in Plone as a content object which you would need to write yourself.
Plone is best when users and editors are entering and approving text in the form of news articles, press releases, photos etc. When that is the use case there are predefined content objects for such things so one does not need to write them oneself.
--Jonathan Mark

Tools and tips for switching CMS

I work for a university, and in the past year we finally broke away from our static HTML site of several thousand pages and moved to a Drupal site. This obviously entails massive amounts of data entry.
What if you're already using a CMS and are switching to another one that better suits your needs? How do you minimize the mountain of data entry during such a huge change? Are there tools built for this, or some best practices one should follow?
The Migrate module for Drupal would provide a big help. The Economist.com data migration to Drupal will give you an overview of the process.
The video from the Migration: not just for the birds presentation at Drupalcon DC 2009 is probably somewhat out-of-date, but also gives a good introduction.
Expect to have to both pre-process and post-process your data manually, whatever happens. Accept early on that your data is likely to be in a worse state than you think it is: fields will be misused; record-to-record references (foreign keys) might not be implemented properly, or at all; content is likely to need weeding and occasionally to be just bad or incorrect.
Check your database encoding. Older databases won't be in Unicode encodings, and get grumpy if you have to export data dumps and import them elsewhere. Even then, assume that there'll be some wacky nonprintable characters in your data: programs like Word seem to somehow inject them everywhere, and I've seen... codepoints... you people wouldn't believe. Consider sweeping your data before you even start (or even sweeping a database dump) for these characters. Decide whether or not to junk them or try to convert them in the case of e.g. Word "smart" punctuation characters.
It's very difficult to create explicit data structures from implied one. If your incoming data has a separate date field, you can map that to a date field; if it has a date as part of a big lump of HTML, even if that date is in a tag with an id attribute, simple scripting won't work. You could use offline scripting with BeautifulSoup or (if your HTML's a bit nicer) the faster lxml to pre-process your data set, extract those implicit fields, and save them into an implicit format. Consider creating an intermediate database where these revisions are going to go.
The Migrate module is excellent, but to get really good data fidelity and play more clever tricks you might need to learn about its hook system (Drupal's terminology for functions following a particular naming scheme) and the basics of writing a module to put these hooks in (a module is broadly just a PHP file where all the functions begin with the same text, the name of the module file.)
All imported content should be flagged for at least a cursory check. You can do this by importing it with status=0 i.e. unpublished, and then create a view with the Views module to go through the content and open it in other tabs for checking. Views Bulk Operations lets you have a set of checkboxes alongside your view items, so you could approve many nodes at once.
Expect to run and re-run and re-run the import, fixing new things every time. Check ten, or twenty items, as early as possible. If there are any problems, check ten or twenty more. Fix and repeat the import.
Gauge how long a single import run is likely to take. Be pessimistic: we had an import we expected to take ten hours encounter exponential slowdown when we introduced the full data set; until we finally fixed some slow queries, it was projected to take two weeks.
If in doubt, or if you think the technical aspects of the above are just going to take more time than the work itself, then just hire temps to do the data. But you still need decent quality controls, as early as possible during their work. Drupal developers are also for hire: try your country's relevant IRC channel, or post a note in a relevant groups.drupal.org group. They're more expensive than temps but they usually write better PHP...! Consider hiring an agency too: that's a shameless plug, as I work for one, but sometimes it's best to get experts in for these specific jobs.
Really good imports are always hard, harder than you expect. Don't let it get you down!
Migrate + table wizard (and schema + views) is the way to go. With table wizard you can expose any table to drupal and map fields accordingly using migrate.
Look here for a detailed walktrough:
http://www.lullabot.com/articles/drupal-data-imports-migrate-and-table-wizard
You'll want to have an access to existing data from django. This helps me a lot with migrating: http://docs.djangoproject.com/en/1.2/howto/legacy-databases/ . With correct model definitions you'll have full django power including the admin. In fact, I'm using django just as admin backend for several legacy php projects - django's admin can easily outachieve a lot of custom hand-written admin scripts.
Authorization should remain the same. Users should be able to login with their credentials but it is hard to write a migration script for auth data because password hashing schemas may be different and there is no way to convert between them without knowing plain passwords. Django provides a way to support different sources of auth so you can write Drupal auth backend: http://docs.djangoproject.com/en/1.2/topics/auth/#writing-an-authentication-backend
There is no need to do the full rewrite. If some parts are working fine they can still be powered by Drupal. New code can written using Django with same UI. Routing between old and new parts can be performed by web server url rewriting. Both django and drupal parts can be powered by the same DB.

CMS for Multilingual Localization and Translation Workflow

I'm helping build a multilingual website in English, Chinese and French (after in Spanish, Korean and Arabic). I've collected a database of over 2000+ entries. It is essentially a huge product catalog (specifically travel packages) where more or less the info is the same (prices, sizes, numbers, etc.) but the labels change (of course excluding certain intro texts that must be written manually). I want to avoid having to translate piece by piece manually.
There needs to be a way for users to save the things they are interested in and rate their favorites. Also, I need an e-commerce shopping cart. Search functionality is a must since people tend to start general (one or two categories or wants) and work towards specifics. Another need is to localization and internationalization. The other need is a specific workflow system so as content is updated and new additions are made, editors can be notified and translators can translate what needs to be done. Work flow is key since the project will involve dozens of non-technical people from around the world.
I originally tried to a work-around solution in Drupal but it seemed ill-equipped and clunky. I tried a self-built PHP CMS but the project seems to big for purely manual. I'm considering Plone and Django, but I don't have any experience working in Python, only PHP. I'm open to trying a new CMS if it meets my needs of internationalization, translation work flow, search functionality and on-going user experience.
Any suggestions on the best CMS for all this?
Plone would be a good solution for the CMS, workflow, search and multilingual.
Ecommerce is not Plone's strength though. I would recommend integrating Plone with something like Satchmo than doing the ecommerce in Plone itself. (This has been done with success in other deployements)
If you are looking at a Django solution to these problems you might consider Satchmo or Lightning Fast Shop for the e-commerce part and Pootle for the translation process...

which layout engine for finding coordinates of html elements on the web page?

I am doing some web data classification task and was thinking if I could get the co-ordinates of html elements as they would appear on a web-browser without taking into consideration any css or javascript being referred in the web page.
My language of programming is c++ and the need results for a couple million of pages, so it has to be fast. I know there is a Microsoft COM component which renders the page in a web browser control and then can be queried for position of different html tags. But this is not suitable in my case as it first renders the whole page which takes up a lot of time.
So as I found out, there are open-source layout engines WebKit, Gecko that can probably be used for this. But that's a huge piece of code and I need someone to direct me to the right classes or right modules to look into or any previous/similar work someone has done previously. Also, please let me know what you guys think is a good choice if I want to customize the existing code for use with multiple threads to make it faster.
Thanks
Generally, you would find that different page rendering engines do render the html in their own way and the results will differ.
The thing is that if you stick to any concrete browser engine, what you are to do is somehow bringing this engine into your project and using engine's interface to retrieve these coordinates. Kind of a tough task though, simply because you'll have to read a lot of documentation and crawl through thousands of files.
I think that right approach would be posting this task in some place, that is specific for the page rendering engine you've chosen. (gecko/webkit/...)
If you prefer sticking to something MS-specific, guess it's gonna be easier, but can't help you with something like class names or code chunks that you want to see. Probably somebody else could guide you in this case.