@logtura/driver-fly-log-tail

Logtura provider driver for Fly.io. Tails flyctl logs --json -a <app> over Vector's exec source. One source per selected app.

npm install @logtura/driver-fly-log-tail @logtura/core

Credentials

A Fly API token. Read-only is strongly recommended:

fly tokens create readonly -o <your-org>

The driver accepts both bare-bearer tokens (legacy) and FlyV1 fm1r_.../fm2_... macaroons. Tokens are revocable from the Fly dashboard.

Usage

import { generateBundle } from "@logtura/core";
import { flyLogTailDriver } from "@logtura/driver-fly-log-tail";

const orgs = await flyLogTailDriver.verifyCredentials({
  apiToken: process.env.FLY_API_TOKEN!,
});
const apps = await flyLogTailDriver.discoverSources({
  credentials: { apiToken: process.env.FLY_API_TOKEN! },
  accountId: orgs[0].id, // org slug
});

const bundle = generateBundle({
  providers: [flyLogTailDriver],
  destinations: [/* ... */],
  connections: [{
    connection: {
      id: "con_a", provider: "fly-log-tail",
      displayName: "prod", externalAccountId: orgs[0].id,
    },
    selectedSources: apps,
    credentials: { apiToken: process.env.FLY_API_TOKEN! },
  }],
  monitors: [/* ... */],
});

Runtime requirements

The forwarder image needs flyctl installed and jq for compacting flyctl's pretty-printed JSON to single-line events. The driver's runtimeSpec returns the Dockerfile install line automatically.

What it emits

Per selected app, one Vector exec source running:

stdbuf -oL flyctl logs --json -a <app> | jq -c --unbuffered --arg app <app> '. + {app: $app}'

stdbuf -oL is required. libc's default block-buffered stdio stalls events in flyctl's pipe until 4 KB accumulates. --arg app ... pre-injects the app name into each event so the driver-level normalize can set .script per source.

Fly's log stream only carries the stdio channel (stdout vs stderr). The application's semantic level is absent from the event. The normalize handles this by trying to parse the message body as structured JSON and preferring an embedded level, severity, or lvl field (pino, winston, bunyan, zap, Go slog, Rust tracing, GCP Logging) before falling back to Fly's stdio channel. As a result, console.warn does not get mis-flagged as an error when Node writes it to stderr.

License

Apache 2.0.