Link: github.com/maxim/doer
Doer is a tiny procedural script for running tasks and commands on multiple subdirectories. It is very useful if you’re creating multi-app projects, like SOA (Service Oriented Architecture) projects.
I purposefully didn’t want to make it into a gem. This project is meant to be a very small hackable tool with all source at fingertips. It won’t grow and develop much from where it is now, as it already has everything it was meant to have.
Install
Step 1
Download “do” and “dofile_sample” into your root directory which contains all your project subdirectories.
Step 2
Step 3
mate dofile
Step 4
Customize your dofile. (See Usage)
When finished – run commands using
Usage
Let’s say you have two applications in your project: foo and bar. They’re in their own subfolders.
Starting “dofile”
We shall create the dofile and start making PROJECTS hash.
HERE = File.dirname(__FILE__)
PROJECTS = {
:foo,
:bar
}
Simple shell commands
Ok, got our setup, now it’s command-making time. First thing – let’s make a “start” command.
:foo => {
:start => "script/server -p6500 -d"
},
:bar => {
:start => "script/server -p6600 -d"
}
}
The above code will allow me to run the following shell commands.
./do start all
./do start foo
./do start bar
The first two lines are identical in function. There are some cases where “all” is required, but mostly it can be omitted when targeting all subfolders.
Using default commands
Let’s write the stop command now.
:foo => {
:start => "script/server -p6500 -d",
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid"
},
:bar => {
:start => "script/server -p6600 -d",
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid"
}
}
Now you notice that :stop is identical for foo and bar. It’d be great to keep it DRY. That’s why there’s :default section.
:default => {
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid"
},
:foo => {
:start => "script/server -p6500 -d"
},
:bar => {
:start => "script/server -p6600 -d"
}
}
:default is a fallback section. It’s only used if a project doesn’t have its own implementation of the requested command.
Linking commands
Time to write :restart. Restart is essentially stop and start. There’s certainly an easy way to do this.
:default => {
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid",
:restart => [:stop, :start]
},
:foo => {
:start => "script/server -p6500 -d"
},
:bar => {
:start => "script/server -p6600 -d"
}
}
That’s all! Now you have:
./do restart foo
./do restart bar
Convenient.
Passing params to commands
Let’s talk about a more interesting case. You want to be able to commit multiple project into your repository, using the same commit message for all. Easy.
:default => {
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid",
:restart => [:stop, :start],
:gc => ["git commit -am \":message\"", %w(message)] # <= this is the new task
},
:foo => {
:start => "script/server -p6500 -d"
},
:bar => {
:start => "script/server -p6600 -d"
}
}
As you can see – we created a :gc command. The “:message” string will be replaced by the first param in the command line. The array basically says that first param is called “message”, which allows us to place a :message token in the string. Now we can do the following.
./do gc foo "Some commit message"
./do gc bar "Some commit message"
Notice: in this case it’s required to use “all” to indicate we want to run across all projects. Otherwise script will think that
“Some commit message” is the name of the project.
Using Procs
Last but not least, you can use Procs. Let’s say you want a task that will verify if a host is running. Let’s pass a proc.
For this we will need a few requires.
require 'uri'
require 'net/http'
PROJECTS = {
:default => {
:stop => "mongrel_rails stop -P tmp/pids/mongrel.pid",
:restart => [:stop, :start],
:gc => ["git commit -am \":message\"", %w(message)]
},
:foo => {
:start => "script/server -p6500 -d",
:status => Proc.new {
begin
message = "Foo Server (localhost:6500)".ljust(35)
Net::HTTP.get(URI.parse('http://localhost:6500'))
rescue
puts message + "OFF"
else
puts message + "RUNNING"
end
}
},
:bar => {
:start => "script/server -p6600 -d",
:status => Proc.new {
begin
message = "Bar Server (localhost:6600)".ljust(35)
Net::HTTP.get(URI.parse('http://localhost:6600'))
rescue
puts message + "OFF"
else
puts message + "RUNNING"
end
}
}
}
You can DRY-up the last example by putting helper methods into dofile. That’s all!
