require 'uri'
require 'net/imap'
require 'stringio'
+require 'time'
+## fucking imap fucking sucks. what the FUCK kind of committee of
+## dunces designed this shit.
+
+## imap talks about 'unique ids' for messages, to be used for
+## cross-session identification. great---just what sup needs! except
+## it turns out the uids can be invalidated every time the
+## 'uidvalidity' value changes on the server, and 'uidvalidity' can
+## change without restriction. it can change any time you log in. it
+## can change EVERY time you log in. of course the imap spec "strongly
+## recommends" that it never change, but there's nothing to stop
+## people from just setting it to the current timestamp, and in fact
+## that's exactly what the one imap server i have at my disposal
+## does. thus the so-called uids are absolutely useless and imap
+## provides no cross-session way of uniquely identifying a
+## message. but thanks for the "strong recommendation", guys!
+
+## so right now i'm using the 'internal date' and the size of each
+## message to uniquely identify it, and i scan over the entire mailbox
+## each time i open it to map those things to message ids. that can be
+## slow for large mailboxes, and we'll just have to hope that there
+## are no collisions. ho ho! a perfectly reasonable solution!
+
+## fuck you, imap committee. you managed to design something as shitty
+## as mbox but goddamn THIRTY YEARS LATER.
module Redwood
class IMAP < Source
- attr_reader :labels
-
- def initialize uri, username, password, last_uid=nil, usual=true, archived=false, id=nil
+ SCAN_INTERVAL = 60 # seconds
+
+ ## upon these errors we'll try to rereconnect a few times
+ RECOVERABLE_ERRORS = [ Errno::EPIPE, Errno::ETIMEDOUT ]
+
+ attr_reader_cloned :labels
+ attr_accessor :username, :password
+
+ def initialize uri, username, password, last_idate=nil, usual=true, archived=false, id=nil
raise ArgumentError, "username and password must be specified" unless username && password
+ raise ArgumentError, "not an imap uri" unless uri =~ %r!imaps?://!
- super uri, last_uid, usual, archived, id
+ super uri, last_idate, usual, archived, id
@parsed_uri = URI(uri)
@username = username
@password = password
@imap = nil
+ @imap_ids = {}
+ @ids = []
+ @last_scan = nil
@labels = [:unread]
- @labels << mailbox.intern unless mailbox =~ /inbox/i || mailbox.empty?
@labels << :inbox unless archived?
+ @labels << mailbox.intern unless mailbox =~ /inbox/i
+ @mutex = Mutex.new
+ end
- connect
+ def host; @parsed_uri.host; end
+ def port; @parsed_uri.port || (ssl? ? 993 : 143); end
+ def mailbox
+ x = @parsed_uri.path[1..-1]
+ x.nil? || x.empty? ? 'INBOX' : x
end
+ def ssl?; @parsed_uri.scheme == 'imaps' end
+
+ def load_header id
+ MBox::read_header StringIO.new(raw_header(id))
+ end
+
+ def load_message id
+ RMail::Parser.read raw_full_message(id)
+ end
+
+ def raw_header id
+ unsynchronized_scan_mailbox
+ header, flags = get_imap_fields id, 'RFC822.HEADER', 'FLAGS'
+ header = header + "Status: RO\n" if flags.include? :Seen # fake an mbox-style read header # TODO: improve source-marked-as-read reporting system
+ header.gsub(/\r\n/, "\n")
+ end
+ synchronized :raw_header
+
+ def raw_full_message id
+ unsynchronized_scan_mailbox
+ get_imap_fields(id, 'RFC822').first.gsub(/\r\n/, "\n")
+ end
+ synchronized :raw_full_message
def connect
- return false if broken?
- return true if @imap
- Redwood::log "connecting to #{@parsed_uri.host} port #{ssl? ? 993 : 143}, ssl=#{ssl?} ..."
-
- ## ok, this is FUCKING ANNOYING.
- ##
- ## what imap.rb likes to do is, if an exception occurs, catch it
- ## and re-raise it on the calling thread. seems reasonable. but
- ## what that REALLY means is that the only way to reasonably
- ## initialize imap is in its own thread, because otherwise, you
- ## will never be able to catch the exception it raises on the
- ## calling thread, and the backtrace will not make any sense at
- ## all, and you will waste HOURS of your life on this fucking
- ## problem.
- ##
- ## FUCK!!!!!!!!!
+ return if broken? || @imap
+ safely { } # do nothing!
+ end
+ synchronized :connect
+
+ def scan_mailbox
+ return if @last_scan && (Time.now - @last_scan) < SCAN_INTERVAL
+ last_id = safely do
+ @imap.examine mailbox
+ @imap.responses["EXISTS"].last
+ end
+ @last_scan = Time.now
+
+ return if last_id == @ids.length
+
+ Redwood::log "fetching IMAP headers #{(@ids.length + 1) .. last_id}"
+ values = safely { @imap.fetch((@ids.length + 1) .. last_id, ['RFC822.SIZE', 'INTERNALDATE']) }
+ values.each do |v|
+ id = make_id v
+ @ids << id
+ @imap_ids[id] = v.seqno
+ end
+ end
+ synchronized :scan_mailbox
+
+ def each
+ ids =
+ @mutex.synchronize do
+ unsynchronized_scan_mailbox
+ @ids
+ end
+
+ start = ids.index(cur_offset || start_offset) or die_from "Unknown message id #{cur_offset || start_offset}.", :suggest_rebuild => true # couldn't find the most recent email
+
+ start.upto(ids.length - 1) do |i|
+ id = ids[i]
+ self.cur_offset = id
+ yield id, labels
+ end
+ end
+
+ def start_offset
+ unsynchronized_scan_mailbox
+ @ids.first
+ end
+ synchronized :start_offset
+
+ def end_offset
+ unsynchronized_scan_mailbox
+ @ids.last
+ end
+ synchronized :end_offset
+
+ def pct_done; 100.0 * (@ids.index(cur_offset) || 0).to_f / (@ids.length - 1).to_f; end
+
+private
+
+ def unsafe_connect
+ say "Connecting to IMAP server #{host}:#{port}..."
+
+ ## apparently imap.rb does a lot of threaded stuff internally and
+ ## if an exception occurs, it will catch it and re-raise it on the
+ ## calling thread. but i can't seem to catch that exception, so
+ ## i've resorted to initializing it in its own thread. surely
+ ## there's a better way.
+ exception = nil
::Thread.new do
begin
#raise Net::IMAP::ByeResponseError, "simulated imap failure"
- @imap = Net::IMAP.new @parsed_uri.host, ssl? ? 993 : 143, ssl?
- @imap.authenticate 'LOGIN', @username, @password
- @imap.examine mailbox
- Redwood::log "successfully connected to #{@parsed_uri}, mailbox #{mailbox}"
+ @imap = Net::IMAP.new host, port, ssl?
+ say "Logging in..."
+
+ ## although RFC1730 claims that "If an AUTHENTICATE command
+ ## fails with a NO response, the client may try another", in
+ ## practice it seems like they can also send a BAD response.
+ begin
+ @imap.authenticate 'CRAM-MD5', @username, @password
+ rescue Net::IMAP::BadResponseError, Net::IMAP::NoResponseError => e
+ Redwood::log "CRAM-MD5 authentication failed: #{e.class}. Trying LOGIN auth..."
+ begin
+ @imap.authenticate 'LOGIN', @username, @password
+ rescue Net::IMAP::BadResponseError, Net::IMAP::NoResponseError => e
+ Redwood::log "LOGIN authentication failed: #{e.class}. Trying plain-text LOGIN..."
+ @imap.login @username, @password
+ end
+ end
+ say "Successfully connected to #{@parsed_uri}."
rescue Exception => e
- self.broken_msg = e.message.chomp # fucking chomp! fuck!!!
- @imap = nil
- Redwood::log "error connecting to IMAP server: #{self.broken_msg}"
+ exception = e
+ ensure
+ shutup
end
end.join
- !!@imap
+ raise exception if exception
end
- private :connect
-
- def mailbox; @parsed_uri.path[1..-1] end ##XXXX TODO handle nil
- def ssl?; @parsed_uri.scheme == 'imaps' end
- def load_header uid=nil
- MBox::read_header StringIO.new(raw_header(uid))
+ def say s
+ @say_id = BufferManager.say s, @say_id if BufferManager.instantiated?
+ Redwood::log s
end
- def load_message uid
- RMail::Parser.read raw_full_message(uid)
+ def shutup
+ BufferManager.clear @say_id if BufferManager.instantiated?
+ @say_id = nil
end
- ## load the full header text
- def raw_header uid
- connect or return broken_msg
- begin
- connect or return broken_msg
- rescue Exception => e
- raise "wtf: #{e.inspect}"
- end
- @imap.uid_fetch(uid, 'RFC822.HEADER')[0].attr['RFC822.HEADER'].gsub(/\r\n/, "\n")
- end
+ def die_from e, opts={}
+ @imap = nil
- def raw_full_message uid
- connect or return broken_msg
- @imap.uid_fetch(uid, 'RFC822')[0].attr['RFC822'].gsub(/\r\n/, "\n")
+ message =
+ case e
+ when Exception
+ "Error while #{opts[:while]}: #{e.message.chomp} (#{e.class.name})."
+ when String
+ e
+ end
+
+ message += " It is likely that messages have been deleted from this IMAP mailbox. Please run sup-import --rebuild #{to_s} to correct this problem." if opts[:suggest_rebuild]
+
+ self.broken_msg = message
+ Redwood::log message
+ BufferManager.flash "Error communicating with IMAP server. See log for details." if BufferManager.instantiated?
+ raise SourceError, message
end
- def each
- connect or return broken_msg
- uids = @imap.uid_search ['UID', "#{cur_offset}:#{end_offset}"]
- uids.each do |uid|
- @last_uid = uid
- @dirty = true
- yield uid, labels
- end
+ ## build a fake unique id
+ def make_id imap_stuff
+ # use 7 digits for the size. why 7? seems nice.
+ msize, mdate = imap_stuff.attr['RFC822.SIZE'] % 10000000, Time.parse(imap_stuff.attr["INTERNALDATE"])
+ sprintf("%d%07d", mdate.to_i, msize).to_i
end
- def start_offset; 1; end
- def end_offset
- connect or return start_offset
- @imap.uid_search(['ALL']).last
+ def get_imap_fields id, *fields
+ raise SourceError, broken_msg if broken?
+ imap_id = @imap_ids[id] or die_from "Unknown message id #{id}.", :suggest_rebuild => true
+
+ retried = false
+ results = safely { @imap.fetch imap_id, (fields + ['RFC822.SIZE', 'INTERNALDATE']).uniq }.first
+ got_id = make_id results
+ die_from "IMAP message mismatch: requested #{id}, got #{got_id}.", :suggest_rebuild => true unless got_id == id
+
+ fields.map { |f| results.attr[f] }
end
+
+ ## execute a block, connected if unconnected, re-connected up to 3
+ ## times if a recoverable error occurs, and properly dying if an
+ ## unrecoverable error occurs.
+ def safely
+ retries = 0
+ begin
+ begin
+ unsafe_connect unless @imap
+ yield
+ rescue *RECOVERABLE_ERRORS
+ if (retries += 1) <= 3
+ @imap = nil
+ retry
+ end
+ raise
+ end
+ rescue Net, SocketError, Net::IMAP::Error, SystemCallError => e
+ die_from e, :while => "communicating with IMAP server"
+ end
+ end
+
end
-Redwood::register_yaml(IMAP, %w(uri username password offset usual archived id))
+Redwood::register_yaml(IMAP, %w(uri username password cur_offset usual archived id))
end
projects / sup / blobdiff