We've been hoping that mkdocs-material will ship the much anticipated
search enhancements for some time, but it's time to recognize that
we need to do something to improve the search results with how
things work right now.
This is a big commit that changes the titles of the various pages
from the code-annotated synopsis to just the name of the function.
This makes it much easier now to match things like `kumo.reject`
directly, but `reject` remains awkward to find.
I think this is the best that we can do at this time.
A few functions have been annotated with the `status: deprecated` to
show as deprecated in the toc/nav (shows with a little trash can next
to the name).
The back story here is that we were investigating a report of
get_egress_path_config sometimes taking a long time (30-60 seconds!) to
complete.
The issue correlates with a large number of TSA entries that
disable the use of TLS for broken sites (>30,000 entries),
and some kind of DNS resolution.
Running the sample of the TSA output through validate-shaping on my
local system can take 30+ seconds to resolve, with a handful of the
entries timing out after 15 seconds (which is 5 seconds timeout on a
query, plus 2 retries of 5 seconds each). In this sort of situation
with a persistently slow resolve on specific domains, the best case
result is therefore 15 seconds, but it could be longer depending on the
ordering of the results and prevailing winds on the upstream dns server.
What's tricky in this situation is that we have to resolve the site
name for each of the entries that have mx_rollup=true enabled in
order to correctly match any given domain when satisfying the
get_egress_path_config event callout. Being lazy with resolution
doesn't help at load time because we're only loaded immediately
prior to invoking this event.
The next logical question to ask is: why do we need to have 30,000+
entries to disable TLS for these broken sites--can't we just retry in
clear text? Well, it's a bit tricky: we're not guaranteed to be able
to continue in clear text after STARTLS fails. If we were to disconnect
and reconnect to the same host immediately after, that's technically
2 connections being made in quick succession to the remote site, and
that might have reputation influencing consequences. I'd like to avoid
adding that sort of reconnection logic without providing a way to
control that behavior, and that is something for a separate change
from this one.
So, looking at the nature of the problematic rule, it doesn't
actually need to be keyed by the site name because there are
not shared limits or constraints that it might make sense to
apply, and in the context of this issue, it's not necessary
to use rollup.
This commit introduces a `SetDomainConfig` action that will
emit a config entry that explicitly sets `mx_rollup=false`
regardless of the value of `mx_rollup` for the defining rule
condition.
When mx_rollup=false, we do not need to resolve the MX
record for the entry when we load the shaping rules,
which eliminates the DNS latency for the aggregate
set of domains with broken TLS.
It would be great if we could automagically fixup the
TSA config database when updating to this version, but
since the rule is an optional part of the suggested
shaping configuration, which may not even be loaded
by a given overall configuration, it's not appropriate
to assume that we should do any fixup.
There's likely a one liner that can be run in sqlite to remove or force
the expiration of the old rules.
Problem scenario: you have defined an automation rule with the
unanchored regex `detected an unusual rate` that triggers a suspension.
What happens: when the remote host initially responds and that
rule matches, a suspension will be created. When subsequent
messages are checked against that rule, the message will not
be attempted (good), but we will generate and log a transient failure
response of the form: `KumoMTA internal: suspended, rule: detected an
unusual rate`. When that response is presented to TSA, since the regex
is unanchored, the original rule will also match it, and that will
cause the duration to be reset, effectively perpetuating the suspension
until the combination of ingress and the retry window exceeds the
duration specified in the rule (bad).
You can explicity mark up your regex with an anchor to prevent
this sort of matching, but it is a PITA to do that for every
suspension rule.
This commit resolves this issue by recognizing that the default
should be to not match internally generated rules. The newly
introduced `match_internal` boolean defaults to false and controls
whether we should consider these internal messages, and allows
the matching to be turned on when needed. We use this in one
of the default shaping rules that is used to disable the use
of tls for broken hosts.
At the lower level, expose an options struct that allows control
over how various checks and conditions are reported out of the
attempt to load the set of shaping files.
Expose a separate list of errors, distinct from warnings.
Each check can either be ignored, a warning, or an error.
Errors cause validate-shaping and --validate mode to exit
with an error condition, whilst warnings are simply emitted
as informational items.
In the shaping helper, it is possible to configure a separate set of
options for the main live service and validation mode, which allows you
to run a more relaxed configuration by default, but be a bit more strict
in your pre-commit and pre-deploy configuration validation pipeline
refs: https://github.com/KumoCorp/kumomta/issues/287
Wez Furlong