STYLEGUIDE

== Style guide for developers.yubico.com
This file documents some common styles and techniques used for content on the
developers website. These are guidelines and not hard rules. In general, they
are available to ensure that the content on the Developers site is as
consistent as possible, and to be a "cookbook" for things the system can do.

=== Developers-only content VS Developers and Github content
The developers site pulls in a lot of content from various Yubico projects on
Github, generating HTML from their README's and any files located in doc/*.
Such content should be formatted in a way which enabled rendering on both
Github and Developers, whereas content that is only displayed on Developers may
freely use Developers-specific formatting.

=== Headers
Each document should have a main title at the start of the document. In
AsciiDoc, this should be using a level 1 title (note that AsciiDoc titles are
zero-indexed, but level 0 is not used for the "article" type). Sections of the
document should be using level 2 titles, and sub-sections may use additional
levels of titles. This document is an example of this structure.

=== Code blocks
Code blocks should be syntax highlighted when possible, and AsciiDoc provides a
method to specify the language rules used for this:

.Example snippet
[source, python]
----
# handles HTTPS requests to /start_registration
def start_registration(username):
  challenge = u2f_lib.start_registration(APP_ID)
  challenge_store.set(username, challenge)
  return challenge
----

=== Command-line examples
Command-line examples should be indented using two spaces:

  $ echo "This is a command."
  $ echo "...and here is a second line!"

When empty lines are needed, the block should instead be surrounded by "....".
Note that indentation in this case is omitted:

....
$ echo "This is another example..."

$ echo "...with a blank line!"
....

Commands should be prefaced with either "$ " or "# " to indicate a prompt
(where # denotes that the command should be run as root). To differentiate a
root prompt from a comment, the comment should end in a # as well:

  # This is a comment #
  # echo "This is a command run as root"
  $ echo "This is a normal command"

On the Developers site these blocks will be rendered in a way where the initial
$ or # symbols for commands won't be selected when selecting a block, to make
copy-paste work better.

=== Sequence charts
If you need to create sequence charts for use on the Developers page, you can
use mscgen and inline the markup for the chart. More information about the
format is available here: http://www.mcternan.me.uk/mscgen/ Note that this will
not be rendered on Github, so it is not recommended for project-level
documents. An example:

[mscgen]
----
msc {
   # Entities
   b [label="Browser"], s [label="Server"], y [label="YubiCloud"];

   # Arcs
   |||;
   b -> s [label = "OTP (and password)"];
   s rbox s [label="Verify password"];
   s -> y [label = "OTP", linecolor="#0000AA", textcolor="#0000AA"];
   y rbox y [label = "Verify OTP", linecolor="#0000AA", textcolor="#0000AA"];
   y -> s [label = "response", linecolor="#0000AA", textcolor="#0000AA"];
}
----