require 'net/imap'
require 'stringio'
require 'time'
+require 'rmail'
## fucking imap fucking sucks. what the FUCK kind of committee of
## dunces designed this shit.
## 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.
-
+## fuck you, imap committee. you managed to design something nearly as
+## shitty as mbox but goddamn THIRTY YEARS LATER.
module Redwood
class IMAP < Source
- attr_reader_cloned :labels
+ SCAN_INTERVAL = 60 # seconds
+
+ ## upon these errors we'll try to rereconnect a few times
+ RECOVERABLE_ERRORS = [ Errno::EPIPE, Errno::ETIMEDOUT ]
+
attr_accessor :username, :password
def initialize uri, username, password, last_idate=nil, usual=true, archived=false, id=nil
@imap = nil
@imap_ids = {}
@ids = []
+ @last_scan = nil
@labels = [:unread]
- @labels << :inbox unless archived?
@labels << mailbox.intern unless mailbox =~ /inbox/i
@mutex = Mutex.new
-
- @recover_msg = "It is likely that messages have been deleted from this IMAP mailbox. Please run sup-import --rebuild #{to_s} to correct this problem."
- 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
- private :say, :shutup
-
- def connect
- return false if broken?
- return true if @imap
-
- ## 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!!!!!!!!!
-
- say "Connecting to IMAP server #{host}:#{port}..."
-
- Redwood::reporting_thread do
- begin
- #raise Net::IMAP::ByeResponseError, "simulated imap failure"
- @imap = Net::IMAP.new host, ssl? ? 993 : 143, ssl?
- say "Logging in..."
- @imap.authenticate 'LOGIN', @username, @password
- say "Sizing mailbox..."
- @imap.examine mailbox
- last_id = @imap.responses["EXISTS"][-1]
-
- say "Reading headers (because IMAP sucks)..."
- values = @imap.fetch(1 .. last_id, ['RFC822.SIZE', 'INTERNALDATE'])
- say "Successfully connected to #{@parsed_uri}."
-
- values.each do |v|
- id = make_id v
- @ids << id
- @imap_ids[id] = v.seqno
- end
- rescue SocketError, Net::IMAP::Error, SourceError => e
- self.broken_msg = e.message.chomp # fucking chomp! fuck!!!
- @imap = nil
- msg = "error connecting to IMAP server: #{self.broken_msg}"
- Redwood::log msg
- BufferManager.flash msg
- ensure
- shutup
- end
- end.join
-
- !!@imap
- end
- private :connect
-
- def make_id imap_stuff
- msize, mdate = imap_stuff.attr['RFC822.SIZE'], Time.parse(imap_stuff.attr["INTERNALDATE"])
- sprintf("%d%07d", mdate.to_i, msize).to_i
end
- private :make_id
def host; @parsed_uri.host; end
def port; @parsed_uri.port || (ssl? ? 993 : 143); end
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
+
+ ## is this necessary? TODO: remove maybe
+ def == o; o.is_a?(IMAP) && o.uri == self.uri && o.username == self.username; end
+
def load_header id
MBox::read_header StringIO.new(raw_header(id))
end
RMail::Parser.read raw_full_message(id)
end
- ## load the full header text
def raw_header id
- @mutex.synchronize do
- connect or raise SourceError, broken_msg
- get_imap_field(id, 'RFC822.HEADER').gsub(/\r\n/, "\n")
- end
+ 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
- @mutex.synchronize do
- connect or raise SourceError, broken_msg
- get_imap_field(id, 'RFC822').gsub(/\r\n/, "\n")
- end
+ unsynchronized_scan_mailbox
+ get_imap_fields(id, 'RFC822').first.gsub(/\r\n/, "\n")
end
+ synchronized :raw_full_message
- def get_imap_field id, field
- retries = 0
- f = nil
- imap_id = @imap_ids[id] or raise SourceError, "Unknown message id #{id}. #@recover_msg"
- begin
- f = @imap.fetch imap_id, [field, 'RFC822.SIZE', 'INTERNALDATE']
- got_id = make_id f[0]
- raise SourceError, "IMAP message mismatch: requested #{id}, got #{got_id}. #@recover_msg" unless got_id == id
- rescue Net::IMAP::Error => e
- raise SourceError, e.message
- rescue Errno::EPIPE
- if (retries += 1) <= 3
- @imap = nil
- connect
- retry
- end
+ 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
- raise SourceError, "null IMAP field '#{field}' for message with id #{id} imap id #{imap_id}" if f.nil?
+ @last_scan = Time.now
+
+ return if last_id == @ids.length
- f[0].attr[field]
+ 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
- private :get_imap_field
-
+ synchronized :scan_mailbox
+
def each
- @mutex.synchronize { connect or raise SourceError, broken_msg }
+ ids =
+ @mutex.synchronize do
+ unsynchronized_scan_mailbox
+ @ids
+ end
- start = @ids.index(cur_offset || start_offset)
- if start.nil? # couldn't find the most recent email
- self.broken_msg = "Unknown message id #{cur_offset || start_offset}. #@recover_msg"
- raise SourceError, broken_msg
- end
- start.upto(@ids.length - 1) do |i|
- id = @ids[i]
+ 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
+ yield id, @labels.clone
end
end
def start_offset
- @mutex.synchronize { connect or raise SourceError, broken_msg }
+ unsynchronized_scan_mailbox
@ids.first
end
+ synchronized :start_offset
def end_offset
- @mutex.synchronize { connect or raise SourceError, broken_msg }
+ 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 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 username password cur_offset usual archived id))