sieve exec for mailinglist subscriptions

[jac-cbi]

All,

I'm so close I can taste it :-)

Under Settings -> Scripting -> System Scripts, I've added four scripts, one each for +subscribe, +sub-confirm, +unsubscribe, and +unsub-confirm. For brevity, I'll only include subscribe.sieve:

require ["vnd.stalwart.expressions", "envelope", "variables", "exec", "notify", "extlists"];

# Extract domain from recipient address
if not envelope :domain :matches "to" "*" {
    discard;
}
set "domain" "${1}";

# Subscribe: listname+subscribe@example.com
if not envelope :matches :localpart "to" "*+subscribe" {
    discard;
}
set "listname" "${1}";

# Does the mailinglist exist?
if not extlists :list "${listname}@${domain}" {
    discard;
}

# Generate the cookie using `cookiemonster`
command :output "cookie" "cookiemonster" ["generate", "${listname}@${domain}", "subscribe", "${from}"];
if string :is "${cookie}" "" {
    discard;
}

# Send a confirmation email
notify :message "Reply to confirm subscription to ${listname}@${domain}"
       :options [
           "Subject=Confirm subscription to ${listname}@${domain} [${cookie}]",
           "Reply-To=${listname}+sub-confirm@${domain}",
           "From=\"${listname} Confirm\" <${listname}+sub-confirm@${domain}>"
       ]
       "mailto:${from}";
discard;

I've wired all four of them up with rcpt == ('listname+subscribe@example.com') => 'subscribe.sieve'. I've verified this with stalwart-cli ... list-config session.data.script.

For all four scripts, when hitting Reload in the web interface, I get the exact same error:

Build error for "sieve.trusted.scripts.subscribe.sieve.contents": Failed to compile trusted Sieve script: Expected token "command" but found "command" at line 0, column 0.

I've tried command, exec, pipe, and nothing else works. Originally, I required pipe, but on reviewing the source code for stalwart, I changed it to exec.

Any ideas how I can get this fixed?

[jac-cbi]

It looks like the error message is due to this code in sieve-rs (src/compiler/grammar/instruction.rs:612):

                        _ => {
                            if state.has_capability(&Capability::Ihave) {
                                state.ignore_instruction()?;
                                state.instructions.push(Instruction::Invalid(Invalid {
                                    name: instruction.to_string(),
                                    line_num: token_info.line_num,
                                    line_pos: token_info.line_pos,
                                }));
                                continue;
                            } else {
                                return Err(CompileError {
                                    line_num: state.block.line_num,
                                    line_pos: state.block.line_pos,
                                    error_type: ErrorType::UnexpectedToken {
                                        expected: "command".into(),
                                        found: instruction.to_string(),
                                    },
                                });
                            }
                        }

I'm unsure if the reported line_num and line_pos are unset 0, or actually at 0...

[jac-cbi]

Sigh. After careful review of the stalwart documentation, I now recall that I had $AI create the first cut of the code (both the rust cookie monster binary and the sieve scripts). It clearly completely hallucinated how to call external binaries 😡

I've now updated it to do the following:

set "fqln" "${listname}@${domain}"
# ...
# Generate the cookie using `cookiemonster`
let "cookie" "exec('/usr/local/bin/cookiemonster', [ 'generate', fqln, 'subscribe', envelope.from ] )";
if string :is "${cookie}" "" {
    discard;
}

Which fixed the compile error.

I then had a second bug in the -confirm.sieve scripts where I wasn't checking the return value and just calling extlists directly. Wrapping them in an if { } fixed that compile error.

Now, All four scripts load / compile without error. Sweet! And .... a test email to +subscribe doesn't work.

[mdecimus]

Since Sieve does not support logging or debugging, your best alternative is using reject statements to make sure that the contents of each variable you are evaluating is correct.

[jac-cbi]

Yeah, I dug into using query('sql', ...), but I'm already established with rocksdb... oops. I've now discovered the lookup plugin which provides key_set and key_get and should work with rocks. However, I'm having a heckuva time trying to divine the key schema so that I can query for mailinglist existence (and add / remove subscribers). I found SUBSPACE_DIRECTORY is 'd', but I've not been having much luck with stalwart-mail --console ... scan. Might have to try ldb to figure it out

[jac-cbi]

Ho sweet!

stalwart-mail -c /etc/stalwart-mail/config.toml -o
> scan d\x00 d\xff

dumped all the keys for the directory!

[jac-cbi]

And its a mix of binary and ascii, some sort of serialized data... :-/