Programmer blog

Sometimes you get a vagrant environment or boilerplate with a Vagrantfile config in there and do a vagrant up command. And see some errors. like this: There are errors in the configuration of this machine . Please fix the following errors and try again : Vagrant: * Unknown configuration section 'hostmanager'. To fix this one needs: $ vagrant plugin install vagrant - hostmanager Installing the ' vagrant-hostmanager ' plugin . This can take a few minutes . . . Fetching : vagrant - hostmanager - 1.8 .6 . gem ( 100 % ) Installed the plugin ' vagrant-hostmanager (1.8.6) ' ! So command to fix this as follows: vagrant plugin install vagrant-hostmanager

Problem: I have an SD flash card (8 GB Kingston) and a MacBook Pro 13" (Late 2011 model). I also use external card reader time to time. This problem persisted on all the conditions. The error message was stating: The Finder can’t complete the operation because some data in “” can’t be read or written. (Error code -36) This was happening while copying Photos from my camera (cr2 files). It worked, however, in case of copying files up to 200 MB in total size of batch. It dropped this error message and did stop to copy files upon selecting of lots of RAW files. E.g. all of them and attempting to copy them from a flash drive. Solution: Problem occurred with building miniatures of the CR2 files. Those files are quite heavy photos (25+ MB) and building miniature did take some time. While building those miniatures on both MAC and SD card finder windows it did die. For me it was enough to change the view from icons to list. E.g.: This did solve it for me. Other solution (Suspect...

Developing a website for Django CMS I have done a plugin. This plugin however have had a problem. It had an m2m field. While selecting images there (It was a gallery plugin). It was not saving it to production. This way main problem with this field was that plugin have displayed m2m choices on a draft page and while storing it to live it fails. Django CMS Pages is built like so it has multiple versions of pages. Each Page model that is changed is stored under new revision. And so plugin is copied and relinked to that page too. So plugin revisions multiply to. For e.g. in case you have a Draft page with two plugins that have model primary key number (pk in future) 12 and 14 accordingly. Say you hit publish changes. Not only PK of Page model rises and data are copypasted into new empty Page model instance. Those plugins are copied to. So mentioned plugins PK would change to 15 and 16 accordingly, assuming 14 is the latest plugin pk. New copied plugins will be linked to new page. Tha...

I have had a problem with compiling Pillow recently. the error was with Pillow/Pil compilation. pillow install error clang: error: unknown argument: '-mno-fused-madd' [-Wunused-command-line-argument-hard-error- in -future] Apple updated command line tools. So the cc command was updated too. $ gcc --version Configured with : --prefix= /Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1 Apple LLVM version 5.1 (clang- 503.0 . 38 ) (based on LLVM 3.4 svn) Target: x86_64-apple-darwin13. 1.0 Thread model: posix The bug is in GCC. It is quite serious because those flags support will be dropped in future. Fortunately there is a worakround for now: export ARCHFLAGS= "-Wno-error=unused-command-line-argument-hard-error-in-future" It works for Pillow 2.4.0 and I can compile it with Apple LLVM 5.1 (That is current now), as of Xcode 5.1. Hope my findings will help someone.

It often gets that you need it because you invent something that is meant to be displayed for admin. E.g. some nasty form field or something. Here is my recipe to add some additional Django static to your admin. Rather than writing a widget , that is more proper way here... I was using a widget already (from another package). So I could not use it properly, at least without a ton of overrides and complexity it leads to. SO I've decided to add the JS functionality to override a lack of backend. First of all we should add the javascript/css like so: # admin.py class MyModelAdmin (admin.ModelAdmin): # admin additions class Media : css = { "all" : ( "css/my_style.css" ,) } js = ( "js/my_script.js" ,) This add should list your files, loaded in the admin . So you can access them and see in the Django admin frontend itself. Like so: Now that your script and style are loaded you could jus...

As a novice I'd like to describe a situation when you may need to make calls to a different domain. In my case it was a requirement to access external API. Anyway I'd like to describe here my perspective of usage this in meteor. You would need to get those data and parse them. First thought is to use client. Wrong. You would need to add CORS support to your application. It means you need to have header  Access-Control-Allow-Origin: * added to all of your response objects. This will enable Meteor usage of external domain responses. And requires you to hack Meteor code. But there is more "proper" way to work with server. Code on a server is executed synchronously and so you can be sure it will be executed and result returned. So. First we need to make sure we have a Meteor.http package installed. You can install it by executing "meteor add http" in your project root directory. Meteor.http can work in both synchronous and asynchronous modes. It is d...

We often get strange errors with python. When you changing the source and cannot figure out why files are used from past. So if you ever get this dejavu feeling, try using this command: find . -type f -name '*.pyc' -exec rm {} \; It will delete all precompiled python sources. (Because with python you have ability to distribute your files in binaries in fact.) Those errors usually appear if you move/delete *.py files with version control. You usually exclude *.pyc files from list. Old links used this way. Debugger does not suggest wrong imports because your files are in fact there, just precompiled. Anyway I've just put this command to my blog for memorizing. It often helps me. Maybe it can for you.

Python plays with unicode nicely nowadays. Bt what if you must deal with old time formats conversion, or ASCII files exporting for e.g. You may also use software that is out of date but is too long to rewrite...  Here often errors occur. I have received mine at copy-pasting from MS Word into Django admin UI  by stupid users. Most of the website played nicely with this fancy characters, but exporting to CSV failed due to non ASCII characters support. Google said nothing special. Python docs about unicode usage briefly cover this type of events. So here is the result of some hours of experiments. I've decided to rewrite some of the python functionality to create decode function with behavior for my needs. Hopefully they will shorten you some time with those collisions you may get in your Django apps... Anyway I've started to receive errors like: Exception Type: UnicodeEncodeError Exception Value: 'asc...

Our project will have a new architecture changes in future. We've chosen from different tech. But now we 're experimenting with CouchDB a bit. It may become a part of our new architectural Changes. I'll try to cover most of newbies observations with CouchDB for Python(Django) programmer, planning to use it in your project. First article will be, unsurprisingly, installing CouchDB under Mac OS X. It, sure, has some inches that you need to scratch. So let's roll... CouchDB is not a simple SQL database like you used to install before. It has own server to accept connections. And, in fact, you can work with database from your browser GUI (without other server proxy, like Django or ...). Anyway it will not be our target. Building JS UI is quite easier with CouchDB and changes your logic dramatically. To build UI with Python we need some proxy parts. Anyway, again, CouchDB is a standalone server, that runs on your server's port and talks to your APP/Browser/wha...

Upon development proces you often meet ManyToMany relations that throw errors in templates. I prefer to feed everything to context and play with it there. This kind of error appears when you iterate through a model's ManyToMany field. To fix it just add a related 'all' manager through dot syntax. Like so: Model: class BannerImage ( models . Model ) : image = models . ImageField ( upload_to = "somedir" ) def get_image_url ( self ) : return 'Image url here' class Banner ( models . Model ) : name = models . CharField ( max_length = 250 , null = True ) images = models . ManyToManyField ( BannerImage ) View/Tag or else, that creates context: banner = get_object_or_404 ( Banner , pk = 1 ) return { 'banner' : banner , } Template causing the error: {% for image in banner . images %} < img src = "{{ image.get_image_url }}" /> {% endfor %} Template without the error: {% ...