dm-regex is a glorifed wrapper to Regexp.compile that matches against strings to build a family of DataMapper models.
It works by mapping named regexp groups to DataMapper properties and associations.
Those groups are then referenced in the pattern string passed to compile using \g<name>, where name is the name of the property.
Associations can also be referenced in the same way; their pattern values come from embeddable versions of their compiled regexes.
To do all this DataMapper::Resource is extended with the following class methods:
- a wrapper for DM's
property, that first extracts any:patand:methodoptions:patoption specifies the pattern used to match the property. (NB. the default pattern of/.+?/might be good enough in most cases):methodoption takes a proc that is used to transform the matched value. (NB. DataMapper's built-in typescasting might be good enough in most cases)
- a glorified wrapper for
Regexp.compilethat uses theMatchDatato build models - uses named groups specified using
\g<name>syntax to map groups to property regexes. (NB. make sure to use\\gwhen using double quoted strings)
- builds a model by matching against
str(returns nil on failure) - where defined, uses the
:patregex to match property values - where defined, uses the transforming
:methodto transform property values - if the parent relationship is given it adds the model to that relationship,
- otherwise it recursivly builds and adds models to all the parent relationships (ie. building up a model "tree" from each "leaf")
- or iteratively adds child models to the parent (ie. building up model "leaves" for the "tree")
gem install dm-regex
require 'dm-regex'
class Host
include DataMapper::Resource
property :id , Serial
property :value , String , :pat => /[.0-9]+/
has n, :requests
# 87.18.183.252
compile '^\g<value>$'
end
class UserAgent
include DataMapper::Resource
property :id , Serial
property :value , String
has n, :requests
# Feedreader 3.13 (Powered by Newsbrain)
compile '^\g<value>$'
end
class Verb
include DataMapper::Resource
property :id , Serial
property :value , String
has n, :request_types
has n, :requests, :through => :request_types
# GET
compile '^\g<value>$'
end
class RequestType
include DataMapper::Resource
property :id , Serial
property :path , String
property :protocol , String , :pat => %r{HTTP/\d.\d}
belongs_to :verb
has n, :requests
# GET /blog/index.xml HTTP/1.1
compile '^\g<verb> \g<path> \g<protocol>$'
end
class Referer
include DataMapper::Resource
property :id , Serial
property :value , String , :pat => /.+/ , :method => lambda { |value| value unless value == '-' }
has n, :requests
# -
compile '^\g<value>$'
end
class Request
include DataMapper::Resource
property :id , Serial
property :l , String , :method => lambda { |value| value unless value == '-' }
property :u , String , :method => lambda { |value| value unless value == '-' }
property :t , DateTime , :method => lambda { |value| DateTime.strptime(value, '%d/%b/%Y:%H:%M:%S %z') }
property :s , Integer
property :b , Integer
belongs_to :host
belongs_to :request_type
belongs_to :user_agent
belongs_to :referer
has 1, :verb, :through => :request_type
# 87.18.183.252 - - [13/Aug/2008:00:50:49 -0700] "GET /blog/index.xml HTTP/1.1" 302 527 "-" "Feedreader 3.13 (Powered by Newsbrain)"
#compile '^\g<host> \g<l> \g<u> \[\g<t>\] "\g<request_type>" \g<s> \g<b> "\g<referer>" "\g<user_agent>"$'
compile %{
^
\\g<host> # This is an EXTENDED regex
[ ]
\\g<l> # it can have comments
[ ]
\\g<u> # and more comments
[ ]\\[
\\g<t> # but IMHO this is
\\]
[ ]"
\\g<request_type> # a lot harder to follow
"[ ] # than the commented out example above
\\g<s> #
[ ] # Actually the groups names
\\g<b> # are self-documenting anyway
[ ]" # aren't they?
\\g<referer> # Plus every \ needs to be escaped
"[ ]" # which is a bit of a pain.
\\g<user_agent> # Anyway .. your choice
"$
}, Regexp::EXTENDED
end
DataMapper.setup :default, "sqlite::memory:"
require 'dm-migrations'
DataMapper.auto_upgrade!
%{\
87.18.183.252 - - [13/Aug/2008:00:50:49 -0700] "GET /blog/index.xml HTTP/1.1" 302 527 "-" "Feedreader 3.13 (Powered by Newsbrain)"
79.28.16.191 - - [13/Aug/2008:00:50:55 -0700] "GET /blog/public/2008/08/gmail-offline-dati-a-rischio/gmaildown.png HTTP/1.1" 304 283 "-" "FeedDemon/2.7 (http://www.newsgator.com/; Microsoft Windows XP)"
79.28.16.191 - - [13/Aug/2008:00:50:55 -0700] "GET /blog/public/2008/08/nuovo-microsoft-webmaster-center/overview.png HTTP/1.1" 304 283 "-" "FeedDemon/2.7 (http://www.newsgator.com/; Microsoft Windows XP)"
69.150.40.169 - - [13/Aug/2008:00:51:06 -0700] "POST http://www.simonecarletti.com/mt4/mt-ttb.cgi/563 HTTP/1.1" 404 610 "-" "-"
217.220.110.75 - - [13/Aug/2008:00:51:02 -0700] "GET /blog/2007/05/microsoft-outlook-pst.php HTTP/1.1" 200 82331 "http://www.google.it/search?hl=it&q=outlook+pst+file+4+GB&meta=" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; .NET CLR 1.1.4322; .NET CLR 2.0.50727)"\
}.split("\n").each do |line|
Request.match(line).tap(&:save)
end
p get = Verb.first(:value => 'GET')
# => #<Verb @id=1 @value="GET">
p get.requests
# => [#<Request @id=1 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:50:49-07:00 ((2454692j,28249s,0n),-25200s,2299161j)> @s=302 @b=527 @host_id=1 @request_type_id=1 @user_agent_id=1 @referer_id=1>, #<Request @id=2 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:50:55-07:00 ((2454692j,28255s,0n),-25200s,2299161j)> @s=304 @b=283 @host_id=2 @request_type_id=2 @user_agent_id=2 @referer_id=1>, #<Request @id=3 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:50:55-07:00 ((2454692j,28255s,0n),-25200s,2299161j)> @s=304 @b=283 @host_id=2 @request_type_id=3 @user_agent_id=2 @referer_id=1>, #<Request @id=5 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:51:02-07:00 ((2454692j,28262s,0n),-25200s,2299161j)> @s=200 @b=82331 @host_id=4 @request_type_id=5 @user_agent_id=4 @referer_id=2>]
p a_host = Host.first(:value => '79.28.16.191')
# => #<Host @id=2 @value="79.28.16.191">
p a_host.requests
# => [#<Request @id=2 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:50:55-07:00 ((2454692j,28255s,0n),-25200s,2299161j)> @s=304 @b=283 @host_id=2 @request_type_id=2 @user_agent_id=2 @referer_id=1>, #<Request @id=3 @l=nil @u=nil @t=#<DateTime: 2008-08-13T00:50:55-07:00 ((2454692j,28255s,0n),-25200s,2299161j)> @s=304 @b=283 @host_id=2 @request_type_id=3 @user_agent_id=2 @referer_id=1>]
p a_referer = Referer.last
# => #<Referer @id=2 @value="http://www.google.it/search?hl=it&q=outlook+pst+file+4+GB&meta=">
p a_referer.requests.hosts
# => [#<Host @id=4 @value="217.220.110.75">]require 'dm-regex'
class Blog
include DataMapper::Resource
property :id , Serial
property :name , String
has n, :posts
end
class Post
include DataMapper::Resource
property :id , Serial
property :title , String , :pat => /[^,]+/
property :author , String
belongs_to :blog
# my interesting blog, [email protected]"
compile '^\g<title>, \g<author>$'
end
DataMapper.setup :default, "sqlite::memory:"
require 'dm-migrations'
DataMapper.auto_upgrade!
blog = Blog.first_or_create(:name => 'foo')
Post.match("my interesting blog, [email protected]", blog.posts).tap(&:save)
p blog.posts
# => [#<Post @id=1 @title="my interesting blog" @author="[email protected]" @blog_id=1>]require 'dm-regex'
class Sentence
include DataMapper::Resource
property :id , Serial
property :value , String
has n, :words
compile '^(?<value>(.*?\g<word>.*?)+(\.|\?|\!))$', Regexp::MULTILINE
end
class Word
include DataMapper::Resource
property :id , Serial
property :value , String , :pat => /\b\w+\b/
belongs_to :sentence
compile '\g<value>'
end
DataMapper.setup :default, "sqlite::memory:"
require 'dm-migrations'
DataMapper.auto_upgrade!
str = "One two\nthree four."
Sentence.match(str).tap(&:save)
p Sentence.all
# => [#<Sentence @id=1 @value="One two\nthree four.">]
p Sentence.first.words
# => [#<Word @id=1 @value="One" @sentence_id=1>, #<Word @id=2 @value="two" @sentence_id=1>, #<Word @id=3 @value="three" @sentence_id=1>, #<Word @id=4 @value="four" @sentence_id=1>]- When passing a double quoted string argument to
compilemake sure to use\\gfor groups and not\g