Improve our MANUAL

Make it contain real use cases and more explanations. We probably need
to add more of the FAQ entries to the MANUAL and point to relevant FAQ
entries from the manual.

Signed-off-by: Sebastian Spaeth <Sebastian@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>
This commit is contained in:
Sebastian Spaeth 2011-08-25 10:18:05 +02:00 committed by Nicolas Sebrecht
parent 654e3ab9dc
commit 3333723ce7
1 changed files with 264 additions and 119 deletions

View File

@ -14,39 +14,44 @@ Powerful IMAP/Maildir synchronization and reader support
.. TODO: :Manual group:
SYNOPSIS
========
offlineimap [-h|--help]
offlineimap [OPTIONS]
| -1
| -P profiledir
| -a accountlist
| -c configfile
| -d debugtype[,...]
| -f foldername[,...]
| -k [section:]option=value
| -l filename
| -o
| -u interface
DESCRIPTION
===========
Most configuration is done via the configuration file. Nevertheless, there are
a few command-line options that you may set for OfflineIMAP.
OfflineImap operates on a REMOTE and a LOCAL repository and synchronizes
emails between them, so that you can read the same mailbox from multiple
computers. The REMOTE repository is some IMAP server, while LOCAL can be
either a local Maildir or another IMAP server.
Missing folders will be automatically created on the LOCAL side, however
NO folders will currently be created on the REMOTE repository
automatically (it will sync your emails from local folders if
corresponding REMOTE folders already exist).
Configuring OfflineImap in basic mode is quite easy, however it provides
an amazing amount of flexibility for those with special needs. You can
specify the number of connections to your IMAP server, use arbitrary
python functions (including regular expressions) to limit the number of
folders being synchronized. You can transpose folder names between
repositories using any python function, to mangle and modify folder
names on the LOCAL repository. There are six different ways to hand the
IMAP password to OfflineImap from console input, specifying in the
configuration file, .netrc support, specifying in a separate file, to
using arbitrary python functions that somehow return the
password. Finally, you can use IMAPs IDLE infrastructure to always keep
a connection to your IMAP server open and immediately be notified (and
synchronized) when a new mail arrives (aka Push mail).
Most configuration is done via the configuration file. However, any setting can also be overriden by command line options handed to OfflineIMAP.
OfflineImap is well suited to be frequently invoked by cron jobs, or can run in daemon mode to periodically check your email (however, it will exit in some error situations).
Check out the `Use Cases`_ section for some example configurations.
OPTIONS
=======
-1 Disable most multithreading operations
Use solely a single-connection sync. This effectively sets the
@ -152,8 +157,7 @@ Blinkenlights
---------------
Blinkenlights is an interface designed to be sleek, fun to watch, and
informative of the overall picture of what OfflineIMAP is doing. I consider it
to be the best general-purpose interface in OfflineIMAP.
informative of the overall picture of what OfflineIMAP is doing.
Blinkenlights contains a row of "LEDs" with command buttons and a log.
@ -230,30 +234,27 @@ English-speaking world. One version ran in its entirety as follows:
TTYUI
---------
TTYUI interface is for people running in basic, non-color terminals. It
prints out basic status messages and is generally friendly to use on a console
or xterm.
TTYUI interface is for people running in terminals. It prints out basic
status messages and is generally friendly to use on a console or xterm.
Basic
--------------------
------
Basic is designed for situations in which OfflineIMAP will be run
non-attended and the status of its execution will be logged. You might use it,
for instance, to have the system run automatically and e-mail you the results of
the synchronization. This user interface is not capable of reading a password
from the keyboard; account passwords must be specified using one of the
configuration file options.
non-attended and the status of its execution will be logged. This user
interface is not capable of reading a password from the keyboard;
account passwords must be specified using one of the configuration file
options.
Quiet
-----
Quiet is designed for non-attended running in situations where normal
status messages are not desired. It will output nothing except errors
and serious warnings. Like Basic, this user interface is not capable
of reading a password from the keyboard; account passwords must be
specified using one of the configuration file options.
It will output nothing except errors and serious warnings. Like Basic,
this user interface is not capable of reading a password from the
keyboard; account passwords must be specified using one of the
configuration file options.
MachineUI
---------
@ -262,8 +263,98 @@ MachineUI generates output in a machine-parsable format. It is designed
for other programs that will interface to OfflineIMAP.
Signals
=======
Synchronization Performance
===========================
By default, we use fairly conservative settings that are safe for
syncing but that might not be the best performing one. Once you got
everything set up and running, you might want to look into speeding up
your synchronization. Here are a couple of hints and tips on how to
achieve this.
1) Use maxconnections > 1. By default we only use one connection to an
IMAP server. Using 2 or even 3 speeds things up considerably in most
cases. This setting goes into the [Repository XXX] section.
2) Use folderfilters. The quickest sync is a sync that can ignore some
folders. I sort my inbox into monthly folders, and ignore every
folder that is more than 2-3 months old, this lets me only inspect a
fraction of my Mails on every sync. If you haven't done this yet, do
it :). See the folderfilter section the example offlineimap.conf.
3) The default status cache is a plain text file that will write out
the complete file for each single new message (or even changed flag)
to a temporary file. If you have plenty of files in a folder, this
is a few hundred kilo to megabytes for each mail and is bound to
make things slower. I recommend to use the sqlite backend for
that. See the status_backend = sqlite setting in the example
offlineimap.conf. You will need to have python-sqlite installed in
order to use this. This will save you plenty of disk activity. Do
note that the sqlite backend is still considered experimental as it
has only been included recently (although a loss of your status
cache should not be a tragedy as that file can be rebuild
automatically)
4) Use quick sync. A regular sync will request all flags and all UIDs
of all mails in each folder which takes quite some time. A 'quick'
sync only compares the number of messages in a folder on the IMAP
side (it will detect flag changes on the Maildir side of things
though). A quick sync on my smallish account will take 7 seconds
rather than 40 seconds. Eg, I run a cron script that does a regular
sync once a day, and does quick syncs (-q) only synchronizing the
"-f INBOX" in between.
5) Turn off fsync. In the [general] section you can set fsync to True
or False. If you want to play 110% safe and wait for all operations
to hit the disk before continueing, you can set this to True. If you
set it to False, you lose some of that safety, trading it for speed.
Security and SSL
================
Some words on OfflineImap and its use of SSL/TLS. By default, we will
connect using any method that openssl supports, that is SSLv2, SSLv3, or
TLSv1. Do note that SSLv2 is notoriously insecure and deprecated.
Unfortunately, python2 does not offer easy ways to disable SSLv2. It is
recommended you test your setup and make sure that the mail server does
not use an SSLv2 connection. Use e.g. "openssl s_client -host
mail.server -port 443" to find out the connection that is used by
default.
Certificate checking
--------------------
Unfortunately, by default we will not verify the certificate of an IMAP
TLS/SSL server we connect to, so connecting by SSL is no guarantee
against man-in-the-middle attacks. While verifying a server certificate
fingerprint is being planned, it is not implemented yet. There is
currently only one safe way to ensure that you connect to the correct
server in an encrypted manner: You can specify a 'sslcacertfile' setting
in your repository section of offlineimap.conf pointing to a file that
contains (among others) a CA Certificate in PEM format which validating
your server certificate. In this case, we will check that: 1) The server
SSL certificate is validated by the CA Certificate 2) The server host
name matches the SSL certificate 3) The server certificate is not past
its expiration date. The FAQ contains an entry on how to create your own
certificate and CA certificate.
StartTLS
--------
If you have not configured your account to connect via SSL anyway,
OfflineImap will still attempt to set up an SSL connection via the
STARTTLS function, in case the imap server supports it. Do note, that
there is no certificate or fingerprint checking involved at all, when
using STARTTLS (the underlying imaplib library does not support this
yet). This means that you will be protected against passively listening
eavesdroppers and they will not be able to see your password or email
contents. However, this will not protect you from active attacks, such
as Man-In-The-Middle attacks which cause you to connect to the wrong
server and pretend to be your mail server. DO NOT RELY ON STARTTLS AS A
SAFE CONNECTION GUARANTEEING THE AUTHENTICITY OF YOUR IMAP SERVER!
UNIX Signals
============
OfflineImap listens to the unix signals SIGUSR1 and SIGUSR2.
@ -310,7 +401,7 @@ KNOWN BUGS
storing messages. Such files can be written to windows partitions. But
you will probably loose compatibility with other programs trying to
read the same Maildir.
- Exclamation mark was choosed because of the note in
- Exclamation mark was chosen because of the note in
http://docs.python.org/library/mailbox.html
- If you have some messages already stored without this option, you will
have to re-sync them again
@ -322,91 +413,145 @@ KNOWN BUGS
- not available anymore since cygwin 1.7
Synchronization Performance
===========================
PITFALLS & ISSUES
=================
By default, we use fairly conservative settings that are good for
syncing but that might not be the best performing one. Once you got
everything set up and running, you might want to look into speeding up
your synchronization. Here are a couple of hints and tips on how to
achieve this.
Sharing a maildir with multiple IMAP servers
--------------------------------------------
1) Use maxconnections > 1. By default we only use one connection to an
IMAP server. Using 2 or even 3 speeds things up considerably in most
cases. This setting goes into the [Repository XXX] section.
Generally a word of caution mixing IMAP repositories on the same
Maildir root. You have to be careful that you *never* use the same
maildir folder for 2 IMAP servers. In the best case, the folder MD5
will be different, and you will get a loop where it will upload your
mails to both servers in turn (infinitely!) as it thinks you have
placed new mails in the local Maildir. In the worst case, the MD5 is
the same (likely) and mail UIDs overlap (likely too!) and it will fail to
sync some mails as it thinks they are already existent.
2) Use folderfilters. The quickest sync is a sync that can ignore some
folders. I sort my inbox into monthly folders, and ignore every
folder that is more than 2-3 months old, this lets me only inspect a
fraction of my Mails on every sync. If you haven't done this yet, do
it :). See the folderfilter section the example offlineimap.conf.
I would create a new local Maildir Repository for the Personal Gmail and
use a different root to be on the safe side here. You could e.g. use
`~/mail/Pro` as Maildir root for the ProGmail and
`~/mail/Personal` as root for the personal one.
3) The default status cache is a plain text file that will write out
the complete file for each single new message (or even changed flag)
to a temporary file. If you have plenty of files in a folder, this
is a few hundred kilo to megabytes for each mail and is bound to
make things slower. I recommend to use the sqlite backend for
that. See the status_backend = sqlite setting in the example
offlineimap.conf. You will need to have python-sqlite installed in
order to use this. This will save you plenty of disk activity. Do
note that the sqlite backend is still considered experimental as it
has only been included recently (although a loss of your status
cache should not be a tragedy as that file can be rebuild
automatically)
If you then point your local mutt, or whatever MUA you use to `~/mail/`
as root, it should still recognize all folders. (see the 2 IMAP setup
in the `Use Cases`_ section.
4) Use quick sync. A regular sync will request all flags and all UIDs
of all mails in each folder which takes quite some time. A 'quick'
sync only compares the number of messages in a folder on the IMAP
side (it will detect flag changes on the Maildir side of things
though). A quick sync on my smallish account will take 7 seconds
rather than 40 seconds. Eg, I run a cron script that does a regular
sync once a day, and does quick syncs inbetween.
USE CASES
=========
5) Turn off fsync. In the [general] section you can set fsync to True
or False. If you want to play 110% safe and wait for all operations
to hit the disk before continueing, you can set this to True. If you
set it to False, you lose some of that safety trading it for speed.
Sync from GMail to another IMAP server
--------------------------------------
Security and SSL
================
This is an example of a setup where "TheOtherImap" requires all folders to be under INBOX::
Some words on OfflineImap and its use of SSL/TLS. By default, we will
connect using any method that openssl supports, that is SSLv2, SSLv3, or
TLSv1. Do note that SSLv2 is notoriously insecure and deprecated.
Unfortunately, python2 does not offer easy ways to disable SSLv2. It is
recommended you test your setup and make sure that the mail server does
not use an SSLv2 connection. Use e.g. "openssl s_client -host
mail.server -port 443" to find out the connection that is used by
default.
[Repository Gmailserver-foo]
#This is the remote repository
type = Gmail
remotepass = XXX
remoteuser = XXX
# The below will put all GMAIL folders as sub-folders of the 'local' INBOX,
# assuming that your path separator on 'local' is a dot.
nametrans = lambda x: 'INBOX.' + x
[Repository TheOtherImap]
#This is the 'local' repository
type = IMAP
remotehost = XXX
remotepass = XXX
remoteuser = XXX
#Do not use nametrans here.
Certificate checking
--------------------
Selecting only a few folders to sync
------------------------------------
Add this to the remote gmail repository section to only sync mails which are in a certain folder::
Unfortunately, by default we will not verify the certificate of an IMAP
TLS/SSL server we connect to, so connecting by SSL is no guarantee
against man-in-the-middle attacks. While verifying a server certificate
fingerprint is being planned, it is not implemented yet. There is
currently only one safe way to ensure that you connect to the correct
server in an encrypted manner: You can specify a 'sslcacertfile' setting
in your repository section of offlineimap.conf pointing to a file that
contains (among others) a CA Certificate in PEM format which validating
your server certificate. In this case, we will check that: 1) The server
SSL certificate is validated by the CA Certificate 2) The server host
name matches the SSL certificate 3) The server certificate is not past
its expiration date. The FAQ contains an entry on how to create your own
certificate and CA certificate.
folderfilter = lambda folder: folder.startswith('MyLabel')
StartTLS
--------
To only get the All Mail folder from a Gmail account, you would e.g. do::
If you have not configured your account to connect via SSL anyway,
OfflineImap will still attempt to set up an SSL connection via the
STARTTLS function, in case the imap server supports it. Do note, that
there is no certificate or fingerprint checking involved at all, when
using STARTTLS (the underlying imaplib library does not support this
yet). This means that you will be protected against passively listening
eavesdroppers and they will not be able to see your password or email
contents. However, this will not protect you from active attacks, such
as Man-In-The-Middle attacks which cause you to connect to the wrong
server and pretend to be your mail server. DO NOT RELY ON STARTTLS AS A
SAFE CONNECTION GUARANTEEING THE AUTHENTICITY OF YOUR IMAP SERVER!
folderfilter = lambda folder: folder.startswith('[Gmail]/All Mail')
Another nametrans transpose example
-----------------------------------
Put everything in a GMX. subfolder except for the boxes INBOX, Draft, and Sent which should keep the same name::
folderfilter = lambda folder: re.sub(r'^(?!INBOX$|Draft$|Sent$)',r'GMX.', folder)
2 IMAP using name translations
------------------------------
Synchronizing 2 IMAP accounts to local Maildirs that are "next to each other", so that mutt can work on both. Full email setup described by Thomas Kahle at `http://dev.gentoo.org/~tomka/mail.html`_
offlineimap.conf::
[general]
accounts = acc1, acc2
maxsyncaccounts = 2
ui = ttyui
pythonfile=~/bin/offlineimap-helpers.py
socktimeout = 90
[Account acc1]
localrepository = acc1local
remoterepository = acc1remote
autorefresh = 2
[Account acc2]
localrepository = acc2local
remoterepository = acc2remote
autorefresh = 4
[Repository acc1local]
type = Maildir
localfolders = ~/Mail/acc1
[Repository acc2local]
type = Maildir
localfolders = ~/Mail/acc2
[Repository acc1remote]
type = IMAP
remotehost = imap.acc1.com
remoteusereval = get_username("imap.acc1.net")
remotepasseval = get_password("imap.acc1.net")
nametrans = oimaptransfolder_acc1
ssl = yes
maxconnections = 2
# Folders to get:
folderfilter = lambda foldername: foldername in [
'INBOX', 'Drafts', 'Sent', 'archiv']
[Repository acc2remote]
type = IMAP
remotehost = imap.acc2.net
remoteusereval = get_username("imap.acc2.net")
remotepasseval = get_password("imap.acc2.net")
nametrans = oimaptransfolder_acc2
ssl = yes
maxconnections = 2
One of the coolest things about offlineimap is that you can inject arbitrary python code. The file specified with::
pythonfile=~/bin/offlineimap-helpers.py
contains python functions that I used for two purposes: Fetching passwords from the gnome-keyring and translating folder names on the server to local foldernames. The python file should contain all the functions that are called here. get_username and get_password are part of the interaction with gnome-keyring and not printed here. Find them in the example file that is in the tarball or here. The folderfilter is a lambda term that, well, filters which folders to get. `oimaptransfolder_acc2` translates remote folders into local folders with a very simple logic. The `INBOX` folder will simply have the same name as the account while any other folder will have the account name and a dot as a prefix. offlineimap handles the renaming correctly in both directions::
import re
def oimaptransfolder_acc1(foldername):
if(foldername == "INBOX"):
retval = "acc1"
else:
retval = "acc1." + foldername
retval = re.sub("/", ".", retval)
return retval
def oimaptransfolder_acc2(foldername):
if(foldername == "INBOX"):
retval = "acc2"
else:
retval = "acc2." + foldername
retval = re.sub("/", ".", retval)
return retval