Module: Legion::LLM::Router::HeaderConstraints

Extended by:
Legion::Logging::Helper
Defined in:
lib/legion/llm/router/header_constraints.rb

Overview

Trusted routing constraints from canonical X-Legion-* headers (SSOT v3 §7.3) or from explicit internal arguments. These are HARD constraints, not body hints — X-Legion-Model is the deliberate escape hatch and is never subject to the D19 body whitelist/blacklist. Malformed trusted hints raise Errors::InvalidHeader (HTTP 400).

Defined Under Namespace

Classes: Value

Constant Summary collapse

HEADER_KEYS = 
{
  provider:         'X-Legion-Provider',
  instance_id:      'X-Legion-Instance',
  model:            'X-Legion-Model',
  tier:             'X-Legion-Tier',
  maximum_attempts: 'X-Legion-Max-Attempts'
}.freeze

Class Method Summary collapse

Class Method Details

.call(headers:, settings_snapshot:) ⇒ Object 



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# File 'lib/legion/llm/router/header_constraints.rb', line 38

def self.call(headers:, settings_snapshot:)
  raw = HEADER_KEYS.transform_values { |name| fetch_header(headers, name) }
  from_internal(
    provider: raw[:provider], instance_id: raw[:instance_id], model: raw[:model],
    tier: raw[:tier], maximum_attempts: raw[:maximum_attempts], settings_snapshot: settings_snapshot
  )
end

.from_internal(settings_snapshot:, provider: nil, instance_id: nil, model: nil, tier: nil, maximum_attempts: nil) ⇒ Object 



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# File 'lib/legion/llm/router/header_constraints.rb', line 46

def self.from_internal(settings_snapshot:, provider: nil, instance_id: nil, model: nil,
                       tier: nil, maximum_attempts: nil)
  Value.new(
    provider:         normalize_provider(normalize_utf8!(provider, HEADER_KEYS[:provider])),
    instance_id:      blank_to_nil(normalize_utf8!(instance_id, HEADER_KEYS[:instance_id])),
    model:            blank_to_nil(normalize_utf8!(model, HEADER_KEYS[:model])),
    tier:             normalize_tier(normalize_utf8!(tier, HEADER_KEYS[:tier])),
    maximum_attempts: normalize_max_attempts(normalize_utf8!(maximum_attempts, HEADER_KEYS[:maximum_attempts]),
                                             settings_snapshot)
  )
end