ferrite
API
Generated with
ferrite/com.worxbend.ferrite/com.worxbend.ferrite.wiring/AllowedHosts

AllowedHosts

com.worxbend.ferrite.wiring.AllowedHosts
object AllowedHosts

Parses the operator-facing ALLOWED_HOSTS setting into the list AllowedHostsFilter needs.

Why this exists at all. Play declares play.filters.hosts.allowed as a list, and a HOCON environment substitution can only ever produce a string. play.filters.hosts.allowed = ${?ALLOWED_HOSTS} therefore looks correct, validates with docker compose config, and then kills the boot with play.filters.hosts.allowed has type STRING rather than LIST the first time the variable is actually set — which is every deployment and no development run, the worst possible place for a failure to hide.

The alternative Play offers is indexed system properties (-Dplay.filters.hosts.allowed.0=… -Dplay.filters.hosts.allowed.1=…), which Lightbend Config does reassemble into a list. That is rejected: it makes the operator hand-maintain array indices in a JAVA_OPTS string, and a skipped index silently truncates the list, which fails as a 403 on one hostname rather than as an error.

So the string stays a string, under a key of ferrite's own, and this is the one place that splits it.

Attributes

Graph
Supertypes
class Object
trait Matchable
class Any
Self type

Members list

Value members

Concrete methods

def parse(raw: String): Seq[String]

Splits on commas, trims, and drops empties, so "localhost, 127.0.0.1," means what it looks like it means.

Splits on commas, trims, and drops empties, so "localhost, 127.0.0.1," means what it looks like it means.

An empty result is a boot failure rather than an empty list. AllowedHostsFilter rejects every request with 403 when its list is empty, so ALLOWED_HOSTS= — a typo, or an unset variable that a shell expanded to nothing — would otherwise produce a service that starts, passes its liveness probe, and answers nothing.

Attributes

Concrete fields

val ConfigKey: String

The configuration key holding the raw comma-separated form. Not play.filters.hosts.allowed: that key is typed as a list by Play's own reference.conf, and giving it a string here would break Configuration's type checking for anything else that reads it.

The configuration key holding the raw comma-separated form. Not play.filters.hosts.allowed: that key is typed as a list by Play's own reference.conf, and giving it a string here would break Configuration's type checking for anything else that reads it.

Attributes

Generated with