In my last post, Subdomain accounts with Ruby on Rails
explaind,
I mentioned that you’d need to modify your /etc/hosts file to use
custom subdomains for development/testing. Apparently, there is a much
better way to handle this that I was introduced to by Nathan de
Vries. Nathan suggests using a gem that I hadn’t
heard of before that bares the name of Ghost (view project on
github).
Ghost describes itself as…
“A gem that allows you to create, list, and modify local hostnames in 10.5 with ease…” —
If you’ve ever had to modify your /etc/hosts file for anything local,
I highly encourage you to check out this shiny gem.
Installing Ghost
Like most gems, you can just install Ghost with the following command.
```
~ : sudo gem install ghost
Password:
Successfully installed ghost-0.1.2-universal-darwin-9
1 gem installed
Installing ri documentation for ghost-0.1.2-universal-darwin-9...
Installing RDoc documentation for ghost-0.1.2-universal-darwin-9...
```
Okay, now that Ghost is installed, let’s see what we can do with it.
Using Ghost for local domains/subdomains
Ghost is fairly straight forward. It’s essentially a friendly wrapper
for
dscl,
which is the Directory Service command line utility
for Mac OS X. I’ve never played with that directly, but it seems that
with Ghost… I shouldn’t need to. :-)
With Ghost, you can add, modify, and delete entries in the Directory
Service by issuing any of the following commands. Let’s start out by
running ghost to see what we have here.
```
~ : ghost
USAGE: ghost add <hostname> [<ip=127.0.1.1>]
ghost modify <hostname> <ip>
ghost delete <hostname>
ghost list
ghost empty
```
Okay, let’s see if there is anything already listed.
```
~ : ghost list
Listing 0 host(s):
```
Nope. Let’s test this out. First, we’ll try to ping a domain name that we hope doesn’t exist.
```
~ : ping bigbrown.cow
ping: cannot resolve bigbrown.cow: Unknown host
```
Alright, now we’ll add bigbrown.cow with ghost.
```
~ : ghost add bigbrown.cow
Password:
[Adding] bigbrown.cow -> 127.0.0.1
```
As you can see, it required root credentials to do this as it’s system-wide. Let’s now see if we can talk to bigbrown.cow.
```
~ : ping bigbrown.cow
PING bigbrown.cow (127.0.0.1): 56 data bytes
64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.047 ms
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.035 ms
^C
--- bigbrown.cow ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max/stddev = 0.035/0.041/0.047/0.006 ms
```
Excellent! If we run ghost list again, we should see this record.
```
~ : ghost list
Listing 1 host(s):
bigbrown.cow -> 127.0.0.1
```
We can modify the record to a non-localhost IP as well with
ghost modify.
```
~ : ghost modify bigbrown.cow 192.168.10.104
[Modifying] bigbrown.cow -> 192.168.10.104
~ : ghost list
Listing 1 host(s):
bigbrown.cow -> 192.168.10.104
```
I’ll let you play with it yourself as there isn’t much to it. This is a great little addition to my development environment. Thanks to Nathan for pointing it out and to Bodaniel Jeanes for creating this useful gem.
