--- /dev/null
+% Test environment setup for [`interimap`(1)] and [`pullimap`(1)]
+% Guilhem Moulin <guilhem@fripost.org>
+
+Introduction
+============
+
+This document describes how to create dummy mail storage for
+[`interimap`(1)] and/or [`pullimap`(1)] development, using
+[Dovecot](https://dovecot.org) as [IMAP4rev1] server. Start by creating
+a new temporary directory:
+
+ $ BASEDIR="$(mktemp --tmpdir --directory)"
+
+(The leading `$ ` in this document are command-line prompt strings, and
+are not part of the command themselves.)
+
+
+Dovecot configuration
+=====================
+
+Create a file `$BASEDIR/dovecot.conf`, which will be used as
+configuration for the various Dovecot commands (the system configuration
+will be skipped).
+
+ $ cat >"$BASEDIR/dovecot.conf" <<-EOF
+ log_path = "$BASEDIR/dovecot.log"
+ ssl = no
+ mail_home = "$BASEDIR/%u"
+ mail_location = maildir:~/mail
+ EOF
+
+Here are some details on the above:
+
+`log_path`
+
+ : Dovecot [logs to syslog](https://wiki.dovecot.org/Logging) by default.
+ It's annoying to clutter syslog with test entries, so instead we make it
+ log to a file under `$BASEDIR`.
+
+`ssl`
+
+ : Not required, but turned off here so dumping the configuration with
+ `` `doveconf -c "$BASEDIR/dovecot.conf" -n` `` doesn't spew a warning.
+
+`mail_home`
+
+ : Dovecot needs the name of the user to (pre-)authenticate. It is shown
+ in the greeting line, and also used in [`%`-variable] expansion.
+ Several [`doveadm`(1)] sub-commands have a `-u` (or `-d`) option which
+ can be used to determine the username. When this option is not set,
+ the username is taken from the `USER` environment variable. If that
+ environment variable is unset as well, then the return string of
+ [`getlogin`(3)](https://pubs.opengroup.org/onlinepubs/9699919799/functions/getlogin.html)
+ is used.
+
+ Similarly, the user's home directory is used in (`~`- and)
+ [`%`-variable] expansion. It's taken from the `HOME` environment
+ variable when the `mail_home` setting is left unset in the Dovecot
+ configuration (and not overridden by the [user database](https://wiki.dovecot.org/UserDatabase)).
+
+ `mail_home` can therefore be left unset if the `HOME` environment
+ variable is consistently set to `$BASEDIR/$USER`. However it's
+ safer to explicitly set it in the configuration file: otherwise a
+ command run in a non-curated environment might mess up with your own
+ mail storage…
+
+`mail_location`
+
+ : The user's mail storage resides — in [Maildir](https://wiki.dovecot.org/MailLocation/Maildir)
+ format — in a directory `mail` under their home directory. This is
+ enough if you're fine with the default IMAP hierarchy delimiter
+ (which depends on the mail format) is used, and if you need a single
+ [IMAP namespace](https://tools.ietf.org/html/rfc2342). For more
+ complex setups you'll need one or more
+ [`namespace {…}` block](https://wiki.dovecot.org/Namespaces).
+
+
+Mail storage access
+===================
+
+Feel free to point a mail client at the dummy mail storage. To start a
+pre-authenticated [IMAP4rev1] in the test environment for username
+`testuser`, list mailboxes, and exit, run:
+
+ $ env -i PATH="/usr/bin:/bin" USER="testuser" \
+ doveadm -c "$BASEDIR/dovecot.conf" exec imap
+ * PREAUTH [CAPABILITY IMAP4rev1 …] Logged in as testuser
+ a LIST "" "*"
+ * LIST (\HasNoChildren) "." INBOX
+ a OK List completed (0.002 + 0.000 + 0.001 secs).
+ q LOGOUT
+ q OK Logout completed (0.001 + 0.000 secs).
+
+For mailbox (create, delete, rename) and message (add, flag update)
+manipulation you can use your mail client, the relevant [IMAP4rev1]
+commands, or simply the [`doveadm`(1)] tools. Here is an example using
+the latter to create a mailbox `foo`, add a sample message to it, and
+finally mark it as `\Seen`.
+
+ $ env -i PATH="/usr/bin:/bin" USER="testuser" \
+ doveadm -c "$BASEDIR/dovecot.conf" mailbox create "foo"
+<!-- -->
+ $ env -i PATH="/usr/bin:/bin" USER="testuser" HOME="$BASEDIR/testuser" \
+ doveadm -c "$BASEDIR/dovecot.conf" exec dovecot-lda -e -m "foo" <<-EOF
+ From: <sender@example.net>
+ To: <recipient@example.net>
+ Subject: Hello world!
+ Date: $(date -R)
+ Message-ID: <$(</proc/sys/kernel/random/uuid)@example.net>
+
+ Hello world!
+ EOF
+<!-- -->
+ $ env -i PATH="/usr/bin:/bin" USER="testuser" \
+ doveadm -c "$BASEDIR/dovecot.conf" flags add "\\Seen" mailbox "foo" "*"
+
+Normally [`dovecot-lda`(1)](https://wiki.dovecot.org/LDA) tries to do a
+userdb lookup in order to determine the user's home directory. Since we
+didn't configure a user database we need to explicitly set the `HOME`
+environment variable.
+
+
+InterIMAP configuration and test
+================================
+
+In this example the peers to synchronize are sharing the same Dovecot
+configuration file `$BASEDIR/dovecot.conf`. Of course, it's also
+possible to use a different configuration on each “server”, for instance
+in order to specify different hierarchy delimiters, namespaces, or mail
+storage format.
+
+Create an [`interimap`(1)] configuration file to synchronize the `local`
+and `remote` accounts.
+
+ $ cat >"$BASEDIR/interimap.conf" <<-EOF
+ database = $BASEDIR/interimap.db
+
+ [local]
+ type = tunnel
+ command = env -i PATH="$PATH" USER="local" doveadm -c "$BASEDIR/dovecot.conf" exec imap
+
+ [remote]
+ type = tunnel
+ command = env -i PATH="$PATH" USER="remote" doveadm -c "$BASEDIR/dovecot.conf" exec imap
+ EOF
+
+Run [`interimap`(1)] without `--watch` in order to create the database.
+
+ $ env -i PATH="$PATH" perl -I./lib -T ./interimap --config="$BASEDIR/interimap.conf"
+ Creating new schema in database file …/interimap.db
+ database: Created mailbox INBOX
+ […]
+
+You can now run [`interimap`(1)] with `--watch` set, here to one second
+to observe synchronisation steps early.
+
+ $ env -i PATH="$PATH" perl -I./lib -T ./interimap --config="$BASEDIR/interimap.conf" \
+ --watch=1 --debug
+
+Use instructions from the [previous section][Mail storage access]
+(substituting `testuser` with `local` or `remote`) in order to simulate
+activity on either end to synchronize. If you run these commands in
+another shell, then make sure to re-set the `BASEDIR` environment
+variable!
+
+
+PullIMAP configuration and test
+===============================
+
+Create a [`pullimap`(1)] configuration file with as section `[foo]`.
+
+ $ cat >"$BASEDIR/pullimap.conf" <<-EOF
+ [foo]
+ type = tunnel
+ command = env -i PATH="$PATH" USER="testuser" doveadm -c "$BASEDIR/dovecot.conf" exec imap
+ statefile = $BASEDIR/pullimap.foo
+ EOF
+
+Run [`pullimap`(1)] without `--idle` in order to create the state file.
+
+ $ env -i PATH="$PATH" perl -I./lib -T ./pullimap --config="$BASEDIR/pullimap.conf" \
+ --no-delivery foo
+
+You can now run [`pullimap`(1)] with `--idle` set.
+
+ $ env -i PATH="$PATH" perl -I./lib -T ./pullimap --config="$BASEDIR/pullimap.conf" \
+ --no-delivery --idle --debug foo
+
+Use instructions from the [previous section][Mail storage access]
+in order to simulate activity on the “remote” server (in the relevant
+mailbox — `INBOX` by default). If you run these commands in another
+shell, then make sure to re-set the `BASEDIR` environment variable!
+
+
+Cleanup
+=======
+
+To remove temporary directories and the message they contain, simply
+recursively remove the directory `$BASEDIR`.
+
+ $ rm -rf -- "$BASEDIR"
+
+
+[IMAP4rev1]: https://tools.ietf.org/html/rfc3501
+[`interimap`(1)]: https://guilhem.org/man/interimap.1.html
+[`pullimap`(1)]: https://guilhem.org/man/pullimap.1.html
+[`doveadm`(1)]: https://wiki.dovecot.org/Tools/Doveadm
+[`%`-variable]: https://wiki.dovecot.org/Variables
projects / interimap.git / commitdiff