## fuck you, imap committee. you managed to design something as shitty
## as mbox but goddamn THIRTY YEARS LATER.
-
module Redwood
class IMAP < Source
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
end
def raw_header id
- @mutex.synchronize do
- connect
- header, flags = get_imap_fields id, 'RFC822.HEADER', 'FLAGS'
- header = "Status: RO\n" + header if flags.include? :Seen # fake an mbox-style read header
- 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
- get_imap_fields(id, 'RFC822').first.gsub(/\r\n/, "\n")
- end
+ 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
-
- say "Connecting to IMAP server #{host}:#{port}..."
+ return if broken? || @imap
+ safely { } # do nothing!
+ end
+ synchronized :connect
- ## 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!!!!!!!!!
+ 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
- exception = nil
- Redwood::reporting_thread do
- begin
- #raise Net::IMAP::ByeResponseError, "simulated imap failure"
- @imap = Net::IMAP.new host, port, ssl?
- say "Logging in..."
- @imap.authenticate 'LOGIN', @username, @password
- scan_mailbox
- say "Successfully connected to #{@parsed_uri}."
- rescue SocketError, Net::IMAP::Error, SourceError => e
- exception = e
- ensure
- shutup
- end
- end.join
+ return if last_id == @ids.length
- die_from exception, :while => "connecting" if exception
+ 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
- @mutex.synchronize { connect or raise SourceError, broken_msg }
+ 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 = 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]
+ start.upto(ids.length - 1) do |i|
+ id = ids[i]
self.cur_offset = id
yield id, labels
end
end
def start_offset
- @mutex.synchronize { connect }
+ unsynchronized_scan_mailbox
@ids.first
end
+ synchronized :start_offset
def end_offset
- @mutex.synchronize do
- begin
- connect
- scan_mailbox
- rescue SocketError, Net::IMAP::Error, SourceError => e
- die_from e, :while => "scanning mailbox"
- end
- end
+ 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
@say_id = nil
end
- def scan_mailbox
- return if @last_scan && (Time.now - @last_scan) < SCAN_INTERVAL
-
- @imap.examine mailbox
- last_id = @imap.responses["EXISTS"][-1]
- return if last_id == @ids.length + 1
- Redwood::log "fetching IMAP headers #{(@ids.length + 1) .. last_id}"
- File.open("asdf.txt", "w") { |f| f.puts "fetching IMAP headers #{(@ids.length + 1) .. last_id}" }
- values = @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
- @last_scan = Time.now
- end
-
def die_from e, opts={}
@imap = nil
message =
case e
when Exception
- "Error while #{opts[:while]}: #{e.message.chomp}."
+ "Error while #{opts[:while]}: #{e.message.chomp} (#{e.class.name})."
when String
e
end
self.broken_msg = message
Redwood::log message
- BufferManager.flash message
+ BufferManager.flash "Error communicating with IMAP server. See log for details." if BufferManager.instantiated?
raise SourceError, message
end
end
def get_imap_fields id, *fields
- retries = 0
- f = nil
+ 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
- f = @imap.fetch imap_id, (fields + ['RFC822.SIZE', 'INTERNALDATE']).uniq
- got_id = make_id f[0]
- die_from "IMAP message mismatch: requested #{id}, got #{got_id}.", :suggest_rebuild => true unless id == got_id
- rescue SocketError, Net::IMAP::Error
- die_from e, :while => "communicating with IMAP server"
- rescue Errno::EPIPE
- if (retries += 1) <= 3
- @imap = nil
- connect
- retry
+ 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
- die_from "Null IMAP field '#{field}' for message with id #{id} imap id #{imap_id}." if f.nil?
-
- fields.map { |field| f[0].attr[field] }
end
+
end
Redwood::register_yaml(IMAP, %w(uri username password cur_offset usual archived id))
projects / sup / blobdiff