require 'uri'
require 'net/imap'
require 'stringio'
+require 'time'
+require 'rmail'
+## 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 nearly as
+## shitty as mbox but goddamn THIRTY YEARS LATER.
module Redwood
-class IMAP
- attr_reader :uri
- bool_reader :usual, :archived, :read, :dirty
- attr_accessor :id, :labels
+class IMAP < Source
+ SCAN_INTERVAL = 60 # seconds
- class Error < StandardError; end
+ ## upon these errors we'll try to rereconnect a few times
+ RECOVERABLE_ERRORS = [ Errno::EPIPE, Errno::ETIMEDOUT ]
- def initialize uri, username, password, last_uid=nil, usual=true, archived=false, id=nil
- raise "username and password must be specified" unless username && password
+ attr_accessor :username, :password
- @uri_s = uri
- @uri = URI(uri)
+ 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_idate, usual, archived, id
+
+ @parsed_uri = URI(uri)
@username = username
@password = password
- @last_uid = last_uid || 1
- @dirty = false
- @usual = usual
- @archived = archived
- @id = id
@imap = nil
- @labels = [:unread,
- archived ? nil : :inbox,
- mailbox !~ /inbox/i && !mailbox.empty? ? mailbox.intern : nil,
- ].compact
+ @imap_ids = {}
+ @ids = []
+ @last_scan = nil
+ @labels = [:unread]
+ @labels << mailbox.intern unless mailbox =~ /inbox/i
+ @mutex = Mutex.new
end
- def connect
- return if @imap
- Redwood::log "connecting to #{@uri.host} port #{ssl? ? 993 : 143}, ssl=#{ssl?}"
- #raise "simulated imap failure"
- @imap = Net::IMAP.new @uri.host, ssl? ? 993 : 143, ssl?
- @imap.authenticate('LOGIN', @username, @password)
- Redwood::log "success. selecting #{mailbox.inspect}."
- @imap.examine(mailbox)
+ 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 check
+ ids =
+ @mutex.synchronize do
+ unsynchronized_scan_mailbox
+ @ids
+ end
+
+ start = ids.index(cur_offset || start_offset) or raise OutOfSyncSourceError, "Unknown message id #{cur_offset || start_offset}."
end
- private :connect
- def mailbox; @uri.path[1..-1] end ##XXXX TODO handle nil
- def ssl?; @uri.scheme == 'imaps' end
- def reset!; @last_uid = 1; @dirty = true; end
- def == o; o.is_a?(IMAP) && o.uri == uri; end
- def uri; @uri.to_s; end
- def to_s; uri; end
- def is_source_for? s; to_s == s; end
+ ## is this necessary? TODO: remove maybe
+ def == o; o.is_a?(IMAP) && o.uri == self.uri && o.username == self.username; end
- def load_header uid=nil
- MBox::read_header StringIO.new(raw_header(uid))
+ def load_header id
+ MBox::read_header StringIO.new(raw_header(id))
end
- def load_message uid
- RMail::Parser.read raw_full_message(uid)
+ def load_message id
+ RMail::Parser.read raw_full_message(id)
end
- ## load the full header text
- def raw_header uid
- connect
- @imap.uid_fetch(uid, 'RFC822.HEADER')[0].attr['RFC822.HEADER'].gsub(/\r\n/, "\n")
+ 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 uid
- connect
- @imap.uid_fetch(uid, 'RFC822')[0].attr['RFC822'].gsub(/\r\n/, "\n")
+ 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 if @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
- connect
- uids = @imap.uid_search ['UID', "#{@last_uid}:#{total}"]
- uids.each do |uid|
- yield uid, labels
- @last_uid = uid
- @dirty = true
+ ids =
+ @mutex.synchronize do
+ unsynchronized_scan_mailbox
+ @ids
+ end
+
+ start = ids.index(cur_offset || start_offset) or raise OutOfSyncSourceError, "Unknown message id #{cur_offset || start_offset}."
+
+ start.upto(ids.length - 1) do |i|
+ id = ids[i]
+ self.cur_offset = id
+ yield id, @labels.clone
end
end
- def done?; @last_uid >= total; 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 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
+ exception = e
+ ensure
+ shutup
+ end
+ end.join
+
+ raise exception if exception
+ end
+
+ def say s
+ @say_id = BufferManager.say s, @say_id if BufferManager.instantiated?
+ Redwood::log s
+ end
+
+ def shutup
+ BufferManager.clear @say_id if BufferManager.instantiated?
+ @say_id = nil
+ end
- def total
- connect
- @imap.uid_search(['ALL']).last
+ 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 get_imap_fields id, *fields
+ imap_id = @imap_ids[id] or raise OutOfSyncSourceError, "Unknown message id #{id}"
+
+ retried = false
+ results = safely { @imap.fetch imap_id, (fields + ['RFC822.SIZE', 'INTERNALDATE']).uniq }.first
+ got_id = make_id results
+ raise OutOfSyncSourceError, "IMAP message mismatch: requested #{id}, got #{got_id}." 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 SocketError, Net::IMAP::Error, SystemCallError, IOError => e
+ raise FatalSourceError, "While communicating with IMAP server: #{e.message}"
+ end
+ end
+
end
-Redwood::register_yaml(IMAP, %w(uri_s username password last_uid usual archived id))
+Redwood::register_yaml(IMAP, %w(uri username password cur_offset usual archived id))
end
projects / sup / blobdiff