Web Search File Key

# Anthropic Messages Web Search with a File-Sourced Provider Key
#
# A minimal Anthropic Messages web-search gateway that sources the shared Brave
# provider key from a projected FILE instead of an environment variable. The
# `file:` source suits a Kubernetes projected Secret mounted at a fixed path:
#
#   * Restart-free rotation: the key is watched and re-read when the projected
#     file changes, so rotating the Secret does not require restarting the proxy.
#   * Fail-closed: an unreadable, empty, oversized, or non-UTF-8 file fails the
#     pipeline build at startup (never a silent unauthenticated callout), and a
#     post-startup removal publishes no key so the callout fails closed.
#
# Unlike web-search-scoped-credentials.yaml, there is no per-user credential:
# every provider callout uses the shared file-sourced `api_key`, so this is the
# simplest config that actually sends a file-sourced key on the wire.
#
#   curl -N http://127.0.0.1:8080/v1/messages \
#     -H 'content-type: application/json' \
#     -d '{"model":"openai/gpt-oss-20b","max_tokens":1024,"stream":true,"messages":[{"role":"user","content":"Use web search to look up potato, then summarize in one sentence."}],"tools":[{"name":"WebSearch","description":"Search the web","input_schema":{"type":"object","properties":{"query":{"type":"string"}},"required":["query"]}}]}'

listeners:
  - name: anthropic-web-search-file-key
    address: "127.0.0.1:8080"
    filter_chains: [web-search-file-key]

filter_chains:
  - name: web-search-file-key
    filters:
      - filter: anthropic_messages_request
        on_invalid: reject
      - filter: iterative_request_router
        initial_step: inference
        max_iterations: 6
        timeout_ms: 90000
        steps:
          - name: inference
            filters:
              - filter: anthropic_web_search
                provider: brave
                # Source the shared provider key from a projected file. A
                # Kubernetes projected Secret mounted here is watched and re-read
                # on rotation (restart-free); an unreadable file fails closed.
                api_key:
                  file: /var/run/secrets/web-search/api-key
                default_context_size: medium
                timeout_ms: 10000
                # Each Brave provider callout executes through this outbound
                # chain; the filtered-subrequest executor enforces destination
                # authority, DNS/SSRF, TLS/SNI, and Host centrally.
                outbound_chain:
                  name: anthropic-web-search-outbound
                  filters:
                    - filter: request_id
              - filter: anthropic_messages_protocol
                default_version: "2023-06-01"
              - filter: router
                routes:
                  - path_prefix: "/v1/messages"
                    cluster: messages-backend
              - filter: load_balancer
                clusters:
                  - name: messages-backend
                    endpoints: ["127.0.0.1:8000"]
            on_result:
              - filter: anthropic_web_search
                key: action
                value: loop
                next: inference
              - default: true
                done: true

insecure_options:
  allow_private_endpoints: true # example proxies to local backends