Go embeds the request URL in *url.Error, so any transport failure — DNS,
TLS, refused, timeout, SSRF dial block — persisted the full Slack webhook
URL into the per-webhook SQLite database via DeliveryResult.Error. That
field is tagged json:"error,omitempty", so a future REST API would have
served it.
maskURLError rebuilds the error preserving Op and the wrapped cause, so DNS
vs TLS vs timeout still read differently and errors.Is/As and Timeout()
keep working; only path, query and userinfo are dropped. Applied where the
errors are born, which covers both the Slack and HTTP targets. url.Parse
embeds the URL too, so ValidateTargetURL's parse branch gets the same
treatment.
The SSRF rejection log now logs the masked URL, and source_logs.html
receives view types rather than raw rows, so no config blob is reachable
from that template.
MaskURL is now the single masker for the whole tree.
The page rendered the stored target config verbatim, exposing the Slack
incoming-webhook URL, which is a bearer credential: anyone holding it can
post to the channel indefinitely, and it cannot be scoped or revoked
per-holder.
Target config now reaches the template only as a TargetView carrying
labelled fields, so no code path can render the raw blob. maskURL keeps
scheme and host and elides the path, and drops query, fragment and
userinfo; every parse failure yields a neutral placeholder rather than
falling back to the stored string. HTTP header values are never rendered,
only a count.
Rendering change only: the stored config format and the delivery path are
unchanged.