svn revision of this library
What is This Library?
This library provides functionality for retrieving email via POP3, the Post Office Protocol version 3. For details of POP3, see [RFC1939] (www.ietf.org/rfc/rfc1939.txt).
Examples
Retrieving Messages
This example retrieves messages from the server and deletes them on the server.
Messages are written to files named 'inbox/1', 'inbox/2', .… Replace 'pop.example.com' with your POP3 server address, and 'YourAccount' and 'YourPassword' with the appropriate account details.
require 'net/pop'
pop = Net::POP3.new('pop.example.com')
pop.start('YourAccount', 'YourPassword') # (1)
if pop.mails.empty?
puts 'No mail.'
else
i = 0
pop.each_mail do |m| # or "pop.mails.each ..." # (2)
File.open("inbox/#{i}", 'w') do |f|
f.write m.pop
end
m.delete
i += 1
end
puts "#{pop.mails.size} mails popped."
end
pop.finish # (3)
-
Call #start and start POP session.
-
Access messages by using #each_mail and/or #mails.
-
Close POP session by calling #finish or use the block form of start.
Shortened Code
The example above is very verbose. You can shorten the code by using some utility methods. First, the block form of ::start can be used instead of ::new, #start and #finish.
require 'net/pop'
Net::POP3.start('pop.example.com', 110,
'YourAccount', 'YourPassword') do |pop|
if pop.mails.empty?
puts 'No mail.'
else
i = 0
pop.each_mail do |m| # or "pop.mails.each ..."
File.open("inbox/#{i}", 'w') do |f|
f.write m.pop
end
m.delete
i += 1
end
puts "#{pop.mails.size} mails popped."
end
end
#delete_all is an alternative for each_mail and delete.
require 'net/pop'
Net::POP3.start('pop.example.com', 110,
'YourAccount', 'YourPassword') do |pop|
if pop.mails.empty?
puts 'No mail.'
else
i = 1
pop.delete_all do |m|
File.open("inbox/#{i}", 'w') do |f|
f.write m.pop
end
i += 1
end
end
end
And here is an even shorter example.
require 'net/pop'
i = 0
Net::POP3.delete_all('pop.example.com', 110,
'YourAccount', 'YourPassword') do |m|
File.open("inbox/#{i}", 'w') do |f|
f.write m.pop
end
i += 1
end
Memory Space Issues
All the examples above get each message as one big string. This example avoids this.
require 'net/pop'
i = 1
Net::POP3.delete_all('pop.example.com', 110,
'YourAccount', 'YourPassword') do |m|
File.open("inbox/#{i}", 'w') do |f|
m.pop do |chunk| # get a message little by little.
f.write chunk
end
i += 1
end
end
Using APOP
The net/pop library supports APOP authentication. To use APOP, use the Net::APOP class instead of the Net::POP3 class. You can use the utility method, Net::POP3.APOP(). For example:
require 'net/pop'
# Use APOP authentication if $isapop == true
pop = Net::POP3.APOP($is_apop).new('apop.example.com', 110)
pop.start(YourAccount', 'YourPassword') do |pop|
# Rest of the code is the same.
endFetch Only Selected Mail Using 'UIDL' POP Command
If your POP server provides UIDL functionality, you can grab only selected mails from the POP server. e.g.
def need_pop?( id )
# determine if we need pop this mail...
end
Net::POP3.start('pop.example.com', 110,
'Your account', 'Your password') do |pop|
pop.mails.select { |m| need_pop?(m.unique_id) }.each do |m|
do_something(m.pop)
end
end
The Net::POPMail#unique_id method returns the unique-id of the message as a String. Normally the unique-id is a hash of the message.