You must reconfigure the guest so it will get its own IP address: Shutdown the guest In the guest's VirtualBox settings, choose Network and switch the network adapter type...

...Unix) or ipconfig (Windows) You can now connect to this IP address using HTTP, SSH, etc. Note that by doing this your VirtualBox guest is fully exposed on the local...

askubuntu.com

...not play nice with gnome-open. You can fix the problem by uninstalling it: sudo apt-get remove exo-utils Note that this may also uninstall XFCE tools like xfce4...

...clean out the database before each example. Use :transaction where possible. Use :deletion for Selenium features or when you have a lot of MyISAM tables. Understanding database cleaning

...to clean out your test database after each test, so the next test can start from a blank database. To do so you have three options: Wrap each test in...

To reduce download time, application servers usually serve content using gzip compression, if the browser supports it. When using a tool like Wget to explicitly download an application's response...

...the server responds with the uncompressed version: wget http://example.com/ If you are curious about the compressed file's size, pass the corresponding HTTP header: wget --header="accept-encoding: gzip...

There are several ways to merge two (or more) PDF files to a single file using the Linux command line. If you're looking for graphical tools to edit or...

...annotate a PDF, we have a separate card for that. PDFtk (recommended) PDFtk is a great toolkit for manipulating PDF documents. You may need to install it first (sudo apt...

web.archive.org

...context) is run outside of transactions, so data created here will bleed into other specs before(:example) is run before each spec inside it, Generally, you'll want a clean...

...setup for each spec so that they are independent of other specs in the same context. Example Consider this spec: describe User, 'something' do before :context do @user = User.make

By default, Twitter Bootstrap's print styles include printing links. /* Bootstrap's way of printing URLs */ @media print { a[href]:after { content: " (" attr(href) ")"; } } If you want to turn that...

We use CarrierWave in many of our projects to store and serve files of various formats - mostly images. A common use case of CarrierWave's DSL is to "process" the...

...versions", for example different resolutions of the same image. Now we could go one step further: What if we want to create versions that have a different file extension than...

Ubuntu has a package mysql-sandbox that lets you install multiple MySQL versions into your user home: Install mysql-sandbox sudo apt install mysql-sandbox Download the version of MySQL...

...you want to use from mysql.com: https://dev.mysql.com/downloads/file/?id=480427 Make sure to choose "Generic Linux" instead of "Ubuntu" so you get a .tar.gz instead of .deb cd into the directory...

stevesouders.com

You can use scheme-less URLs (or protocol-relative URLs) to have browsers use the current protocol (HTTP or HTTPS) when loading content referenced with such an URL.

...relative URL doesn’t contain a protocol. For example, http://stevesouders.com/images/book-84x110.jpg becomes //stevesouders.com/images/book-84x110.jpg Browsers substitute the protocol of the page itself for the resource’s missing protocol. Problem solved...

...run our end-to-end tests with headless Chrome. While it's a very stable solution overall, we sometimes see the headless Chrome process freeze (or the Capybara driver losing...

...connection, we're not sure). The effect is that your test suite suddenly stops progressing without an error. You will eventually see an error after a long timeout but until...

Sometimes you want to see what data you get through a TCP or UDP connection. For example, you want to know how a HTTP Request look like.

...easy with netcat. Example to listen on port 80 and the output gets to stdout. sudo nc -kl 80 It's also possible write it into a file:

...nested projects. Then it's really helpful! This makes use of the CDPATH variable. Similar to the PATH variable, which holds the list of directories which are searched for executables...

Then add the following to your ~/.bashrc: export CDPATH=.:~/.bookmarks/ function mark { ln -sr "$(pwd)" ~/.bookmarks/"$1" } # Always resolve symbolic links (e.g. for bookmarks) alias cd="cd -P"

When using custom properties in your stylesheets, you may want to set a specific property value to an existing variable in your SASS environment. A pratical example would be a...

...existing quotes, you may use the meta.inspect() function: @use "sass:meta" $my-cool-font: "Roboto", sans-serif :root --font-family-sans-serif: #{meta.inspect($my-cool-font)} Unfortunately, the output of...

...take a long time, so we only want to compile when needed. This card shows what will cause Webpacker (the Rails/Webpack integration) to compile your assets. When you run a...

While development it is recommended to boot a webpack dev server using bin/webpack-dev-server. The dev server compiles once when booted. When you access your page on localhost before...

...will never return the current element itself, even if the element matches the given selector. Require the attached file and you can now say: $('.container').findWithSelf('.selector')

makandra dev

When you're getting this error, one possibility is that you've created a select field for an association instead of the associated object's id. Example: form.select :unit, Unit.for...

will be expected to deliver a real Unit object, whereas form.select :unit_id, Unit.for_select will make Rails typecast the String value from the select field to the unit...

Selenium cannot reliably control a browser when its window is not in focus, or when you accidentally interact with the browser frame. This will result in flickering tests, which are...

...tests to complete. The solution is to run Selenium inside a VNC session so the Selenium-controlled browser doesn't pop up over your main work area. Understanding issues with...

amundsen.com

...but REST itself - in a nutshell. so here's a new angle i've started playing with: "REST Upside Down...

You have to specify the environment with -e env_name or RAILS_ENV=env_name if you want to run a script on the server. at Rails 2 it's...

bundle exec script/runner -e env_name path/to/script.rb argument1 argument2 ... at Rails 3 it's rails runner RAILS_ENV=env_name bundle exec rails runner path/to/script.rb argument1 argument2...

kb.wisc.edu

When receiving a new SSL-Certificate for an existing SSL-key it should be checked that they match cryptographically. Maybe the customer accidentally created a new key and certificate and...

...sent us just the certificate. It's also possible that the certificate chain is in the wrong order. Make sure that the server certificate is the first. This is also...

coding.smashingmagazine.com

JavaScript engines such as Google’s V8 (Chrome, Node) are specifically designed for the fast execution of large JavaScript applications. As you develop, if you care about memory usage and...

...what’s going on in your user’s browser’s JavaScript engine behind the scenes...

commandlinefu.com

The colors in Rails log files are helpful when watching them but, since they are ANSI color codes like ^[[4;36;1m, can be annoying when you are reading the...

...that does just prints those control characters (like less or vim). Remove them with sed: cat staging.log | sed -r "s/\x1B\[([0-9]{1,3}((;[0-9]{1,3})*)?)?[m...

Sometimes you want Angular to watch an object only until a certain state is reached (e.g. an object appears in the scope). Angular's $watch returns a method that you...

...can call to remove that watch. For example: unwatch = $scope.$watch 'user', (user) -> if user?

unwatch()