Append to attribute values using jQuery

Quite a productive day today, here’s another note to self containing a nice jQuery snippet that appends a string to a given attribute of a certain tag. I got the snippet from stackoverflow (of course).

<script>
  $.fn.appendAttr = function(attrName, suffix) {
    this.attr(attrName, function(i, val) {
        return val + suffix;
    });
    return this;
  };
</script>

I am doing some content work in a mixed php/perl/legacy web environment. I added some code to the part of the system that I have access to that hides the content I am working on unless I add a &preview in the URL. Because I part of the system that generates the menus, I had to add the &preview manually. This snippet allows me to stay in preview mode once I have entered preview mode.

<script>
  $( document ).ready(function() {
    if (window.location.href.match(/&preview$/).length > 0) {
        $( "a").appendAttr('href', '&preview')
    }
  });
</script>

Yay.

Zotero + Ulysses 3 + pandoc workflow

Ok, just a quick post as a note to self on my Ulysses 3 + Zotero workflow:

References in Zotero
AutoZotBib Extension to sync Zotero references to a biblatex file.
Write text in Ulysses 3, use pandoc citation syntax.
Export text from Ulysses 3.
Use pandoc + citeproc-hs (which is included in the pandoc package if installed via cabal) to convert to whatever.

Zotero settings

Zotero has a hidden preference setting called extensions.zotero.recursiveCollections (or just recursiveCollections if using the desktop version). Setting the value of this to true, instead of the default false value, selecting a folder also displays the contents of its sub-folders. I think this behaviour makes sense for a document management system (where finding a document is more important than knowing where it resides).

To change the value of extensions.zotero.recursiveCollections, just go to about:config, find the preference name and then double click the value.

Login over SSH using SSH key

I just set this up and it works like a charm. However I imagine that I won’t be doing this every day, so I am writing this note to my future self.

How logging in on a remote server using an SSH key works (intuition)

This is sort of my non-expert, but technically viable understanding of how all of this magic works.

Create a pair of keys using the command ssh-keygen – one public key, and one private key.
Upload the public key (that can be used to confirm the identity something generated using of the private key I believe), to the server (each user has a ~/.ssh/authorized_keys on the server).
Make sure the .ssh directory on the server is only readable by your user.
Make sure the directory where you store your key pair on your local computer is also only readable by you.
When logging in, point ssh to use your private key, for the correct user on the remote server.

Commands

Create your ssh key pair using

ssh-keygen -t rsa -b 2048 -f ~/.ssh/id_rsa -C "Enter an optional comment about your key"

You can use another name than id_rsa. A public companion with the suffix .pub will also be created. You do not have to enter a passphrase, e.g. when using the key via a script.

Protect your local .ssh directory using the following:

chmod 700 ~/.ssh && chmod 600 ~/.ssh/*

Upload the public key via ssh:

cat ~/.ssh/id_rsa.pub | ssh user@remote-server.com 'cat - >> ~/.ssh/authorized_keys'

Protect the .ssh directory on your remote server (remote shell) using:

chmod 600 ~/.ssh/authorized_keys && chmod 700 ~/.ssh/

ssh -i ~/.ssh/id_rsa user@remote-server.com

where id_rsa is your private key.