Export the memory statistics for each spool database to prometheus for
charting and tracking.
Allow the hosting application to request a cache purge and set up a
monitor task to do that when memory usage is too high. That step will
print the memory that it reclaimed when it kicks in.
I noticed that some end to end tests are load shedding, and I think
it is because we initialize headroom to 0 and are racing with
the memory monitor thread startup.
Let's default to non-zero instead.
I think this is manifesting in CI because it has noisy neighbors
on the VM hosts.
I realized that we hadn't connected this up to the memory monitor,
so this commit does that.
I'd like to hook this up for every LruCacheWithTtl, but that
requires some more extensive changes.
I'll look that in a follow up commit.
This provides a simpler and easier to use option for dealing with broken
TLS.
The back story here is that sites with broken TLS ideally should result
in a TLS failure and return us to a clear text SMTP session that we
could use for the remainder if we are in opportunistic mode.
In practice, it's not that simple:
* The rustls implementation provides into_fallible() to enable this mode
of operation, but certain handshake errors result in the session being
unusable once the failed handshake has been communicated
* Openssl is perfectly capable of operating this way, but the Rust
ecosystem bindings do not expose the handshake failure in a way that
allows the clear text session to continue
If we wanted to allow the session to communicate with the failed host in
clear text we will need to make a new separate connection for this case.
There is a concern that this will bump a connection counter in a
reputation system implemented on the destination host, but it is
reasonable to wonder if a site that has broken TLS would be sufficiently
sophisticated to employ such a system.
If we did want to allow making a new connection to the same host, it is
a bit awkward to fit into our current mx host connection plan system.
So, with all that in mind, this commit tries a slightly different
approach:
* A new `remember_broken_tls = "3 days"` field in the egress path config
will enable an in-process cache to keep track of the site_names that
advertise STARTTLS and for which we failed to handshake, or failed to
re-EHLO after a handshake.
* That will cause the connection plan to move on to subsequent hosts, if
any. It won't cause us to re-attempt the current host.
* Subsequent connection attempts (which may be immediate if there are
additional hosts in the current session plan) will consult the
broken tls cache for the site, and use that to decide on the
availability of TLS
* If we previously encountered broken TLS, we will effectively treat
the site as not advertising TLS in EHLO, but will generate an
appropriate error message if TLS is Required.
Since we track the breakage in a cache with per-item TTLs, you
can set the duration as appropriate to your situation.
The cache will be cleared when the process is restarted.
There is no sharing of the cache between nodes.
This is a much lower complexity solution than the existing workaround
using TSA automation rules to override the site with Disabled TLS, and
will help to minimize the number of rules for that purpose in the TSA
daemon.
Note that this commit doesn't change any behavior; we can do a followup
commit to replace those TSA rules with this mechanism.
This reverts commit 401df30099.
The docker merge step is failing:
```
envconfig.Process: assigning PULLREQUEST_DRONE_PULL_REQUEST to Number: converting '' to type int. details: strconv.ParseInt: parsing "": invalid syntax
```
It seems that the compatibility change in
https://github.com/woodpecker-ci/woodpecker/pull/3939 isn't sufficient.
Let's see if we can still run with the environment set manually,
or if we'll need to blackjack our own woodpecker plugin for this.
If you have a get_queue_config event handler that raises an error, it
will propagate back to the injector as a transient error, which is the
desired behavior.
However, we didn't ensure that the message was removed from the spool in
that situation, which could lead to duplicate sends of the same logical
message.
This commit makes things more robust in the context of this kind of
local configuration issue:
* QueueManager::insert_or_unwind is now the preferred way to handle
insertion of the message into the queue during reception at the point
of ingress. It will take care to remove the message from the spool
and to adjust the accounting by logging a Bounce record to complement
the Reception that it assumes that its caller has just logged for the
message.
* Both SMTP and HTTP listeners have been updated to use
insert_or_unwind.
* Spool enumeration has been updated to count failed inserts and to
summarize that the failure is serious and that the messages are not
going to go anywhere until the configuration issue is addressed and
the server is restarted. Note that we cannot recover from this while
the server is online because we have to perform a full spool
enumeration in order to re-discover those messages. (We could
potentially build a thing to remember the complete list of messages,
but I'd rather not try to address what is essentially a configuration
deployment validation problem with engineering on this end of things.)
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.
Dirkjan Ochtman
Mike Hillyer
Mike Hillyer
Wez Furlong
Nathalie Caiandncai