What causes "#{gate} is not supported by this adapter yet" in flippercloud/flipper?

List the gate types to find the offender: feature.gates.map { |g| [g.key, g.data_type] } — anything outside %i[boolean integer set json] is the problem.

flippercloud/flipper · error · RuntimeError

#{gate} is not supported by this adapter yet

Error message

#{gate} is not supported by this adapter yet

What it means

The PStore adapter (shipped inside the flipper gem) persists gate values under 'feature_key/gate_key' paths and picks the storage operation from Gate#data_type inside a transaction: :boolean clears all gates then writes, :integer writes, :set appends a member, :json writes via Typecast.to_json; the else branch raises (lib/flipper/adapters/pstore.rb:77-92). All built-in gates map to those four types and Feature#gates is a fixed set (lib/flipper/feature.rb:412-420), so this raise comes from a gate the adapter was never taught — a custom Gate subclass or a spec double — or a flipper release old enough to predate the :json branch receiving expression writes.

Source

Thrown at lib/flipper/adapters/pstore.rb:90

          read_many_features(features)
        end
      end

      # Public
      def enable(feature, gate, thing)
        @store.transaction do
          case gate.data_type
          when :boolean
            clear_gates(feature)
            write key(feature, gate), thing.value.to_s
          when :integer
            write key(feature, gate), thing.value.to_s
          when :set
            set_add key(feature, gate), thing.value.to_s
          when :json
            write key(feature, gate), Typecast.to_json(thing.value)
          else
            raise "#{gate} is not supported by this adapter yet"
          end
        end

        true
      end

      # Public
      def disable(feature, gate, thing)
        case gate.data_type
        when :boolean
          clear(feature)
        when :integer
          @store.transaction do
            write key(feature, gate), thing.value.to_s
          end
        when :set
          @store.transaction do
            set_delete key(feature, gate), thing.value.to_s

View on GitHub (pinned to 1f86de3ec9)

Solutions

List the gate types to find the offender: feature.gates.map { |g| [g.key, g.data_type] } — anything outside %i[boolean integer set json] is the problem.
Re-map the custom gate's data_type to :json (values serialize with Flipper::Typecast.to_json and read back with from_json) or another supported type.
Fix spec doubles to return a real built-in gate or a supported data_type symbol.
If the running flipper predates :json support (pre-expression releases), upgrade the flipper gem — current releases handle :json in PStore#enable.

Example fix

# before: custom gate with an unknown data type
class Gates::Bucket < Flipper::Gate
  def data_type = :float # PStore#enable raises '... is not supported by this adapter yet'
end

# after: reuse the json data type
class Gates::Bucket < Flipper::Gate
  def data_type = :json # stored via Typecast.to_json, read via Typecast.from_json
end

Defensive patterns

Strategy: validation

Validate before calling

SUPPORTED = %i[boolean integer set json].freeze

def gates_persistable?(feature)
  feature.gates.all? { |g| SUPPORTED.include?(g.data_type) }
end

raise ArgumentError, 'unsupported gate in feature set' unless gates_persistable?(feature)

Type guard

def supported_data_type?(gate)
  %i[boolean integer set json].include?(gate.data_type)
end

Try / catch

begin
  feature.enable(thing)
rescue RuntimeError => e
  raise unless e.message.include?('is not supported by this adapter yet')
  warn "flipper/pstore: gate #{feature.key} rejected: #{e.message}"
end

Prevention

Map custom gate values onto :json (Typecast.to_json/from_json) instead of new data types.
Check gate.data_type via Gate#inspect when adding gates to confirm it reports a supported symbol.
Avoid spec doubles for gates; use the real Flipper::Gates classes.
Upgrade flipper as a whole so the pstore adapter and gate set always match.

When it happens

Trigger: feature.enable(...) (or enable_actor/enable_percentage_of_*) where gate_for(thing) matches a custom gate or test double whose data_type is not :boolean/:integer/:set/:json — for example a gate ported from a patched flipper fork that added a data type such as :float.

Common situations: Building custom targeting gates against the pstore adapter; a monorepo where one app runs a patched flipper with extra data types while another writes via stock pstore; RSpec gate doubles that omit data_type.

Related errors

AI-assisted analysis of flippercloud/flipper@1f86de3ec9 (2026-08-23). Data as JSON: /api/errors/a5b9a939ae3818b8. Report an issue: GitHub.