fly.toml

# See https://fly.io/docs/reference/configuration/ for information about how to use this file.

app = "FILL_IN_YOUR_WARPSTREAM_APP_NAME"
# Set whatever region you prefer here: https://fly.io/docs/reference/regions/
primary_region = "atl"
kill_signal = "SIGINT"
kill_timeout = "1m0s"

[build]

[env]
  # For the Agents to report IP6 IP addresses for internal communication between them within the
  # fly.io network because fly.io does not support IP4 internally.
  WARPSTREAM_ADVERTISE_HOSTNAME_STRATEGY = "auto-ip6"
  # This is required because otherwise the Agent's will advertise their internal fly.io IP6
  # address to the service discovery system for the Kafka service, but this IP address is
  # not routable from outside of your fly.io VPC.
  WARPSTREAM_DISCOVERY_KAFKA_HOSTNAME_OVERRIDE = "YOUR_APP_NAME.fly.dev"
  # This one is not required, but is included in case you want to expose the Kafka protocol
  # on a port besides 9092 externally.
  WARPSTREAM_DISCOVERY_KAFKA_PORT_OVERRIDE = "9092"
  # The value for this can be found in the "Virtual Clusters" section of the WarpStream admin
  # console.
  WARPSTREAM_DEFAULT_VIRTUAL_CLUSTER_ID = "FILL_ME_IN_FROM_WARPSTREAM_ADMIN_CONSOLE"
  # Fill this in with values for your S3 bucket. The example uses Cloudflare R2, but any S3-compatible
  # object store will work.
  WARPSTREAM_BUCKET_URL = "s3://FILL_ME_IN_BUCKET_NAME?s3ForcePathStyle=true&region=auto&endpoint=https://FILL_ME_IN_ENDPOINT.r2.cloudflarestorage.com"
  # Make sure the Agents will enforce authentication.
  WARPSTREAM_REQUIRE_AUTHENTICATION = "true"

[[services]]
  # Agents will listen for Kafka traffic on port 9092 by default.
  protocol = "tcp"
  internal_port = 9092
  processes = ["app"]

  [[services.ports]]
    # Expose Kafka on port 9092 externally as well, and ask fly.io to perform TLS termination
    # for us.
    port = 9092
    handlers = ["tls"]

  [services.concurrency]
    type = "connections"
    # The rationale here is that we don't want fly.io to take "closeness" into account for load
    # balancing purposes at all, at least not when we're deployed within a single region. Instead,
    # we want fly.io to focus exclusively on keeping the number of connections amongst the agents
    # as even as possible. Therefore we set the soft_limit to 0 so all the agents look like they're
    # over their soft limit which encourages fly.io to route new connections to the least loaded
    # instance instead of the closest one.
    hard_limit = 1000
    soft_limit = 0

[[services.tcp_checks]]
  grace_period = "5s"
  interval = "15s"
  timeout = "5s"

[metrics]
  # Collect prometheus metrics automatically.
  port = 8080
  path = "/metrics"