no database set in config, queue commands require the `pg-qu

Error message

no database set in config, queue commands require the `pg-queue` database backend

What it means

All `voyager queue ...` subcommands (enqueue, requeue, etc.) construct a persistent work queue from `VoyagerConfig.queue`, which is a tagged enum (`QueueConfig`: `in-memory` or `pg-queue`). Only `pg-queue` can be opened as a standalone durable queue from the CLI, because an in-memory queue lives only inside a running relayer process and cannot serve out-of-process queue commands. When the config selects `in-memory`, the closure returns this error before any queue operation starts.

Source

Thrown at voyager/src/main.rs:262

                    .map(|module_config| get_plugin_info(&module_config).map(|p| p.name))
                    .collect::<Result<Vec<_>, _>>()?;

                print_json(&list);
            }
        },
        Command::Queue(cli_msg) => {
            let db = || {
                Ok(match get_voyager_config()?.voyager.queue {
                    QueueConfig::PgQueue(cfg) => {
                        pg_queue::PgQueue::<VoyagerMessage>::new(PgQueueConfig {
                            // only one connection is needed for the queue commands
                            min_connections: 1,
                            max_connections: 1,
                            ..cfg
                        })
                    }
                    QueueConfig::InMemory => {
                        return Err(anyhow!(
                            "no database set in config, queue commands \
                            require the `pg-queue` database backend"
                        ));
                    }
                })
            };

            match cli_msg {
                QueueCmd::Enqueue { op, rest_url } => {
                    let rest_url = get_rest_url(rest_url);

                    send_enqueue(&rest_url, op).await?;
                }
                QueueCmd::Stats => {
                    let stats = db()?.await?.stats().await?;

                    print_json(&stats);
                }

View on GitHub (pinned to 031785bb6d)

Solutions

Edit the Voyager config TOML and set the queue to the Postgres backend with a reachable database URL: `queue = { type = "pg-queue", database-url = "postgres://user:pass@host:5432/voyager" }`.
Confirm Postgres is reachable and the database exists (`psql <url> -c 'select 1'`); apply migrations if this is a fresh database.
If you did not intend to use queue commands, drop them from your command/script — relaying itself works with either backend.
If you intended a durable setup, re-generate or diff your config against a known-good production config so other required fields stay valid.

Example fix

# before (config.toml)
queue = { type = "in-memory" }
# $ voyager queue enqueue ...
# error: no database set in config, queue commands require the `pg-queue` database backend

# after (config.toml)
queue = { type = "pg-queue", database-url = "postgres://postgres:postgres@localhost:5432/voyager" }

Defensive patterns

Strategy: validation

Validate before calling

# fail fast before running queue commands
tomlq -r '.queue.type' "$VOYAGER_CONFIG" | grep -qx 'pg-queue' || {
  echo "queue commands require queue.type = pg-queue in $VOYAGER_CONFIG" >&2; exit 2;
}

Type guard

fn has_pg_queue(cfg: &VoyagerConfig) -> bool {
    matches!(cfg.queue, QueueConfig::PgQueue(_))
}

Prevention

Generate production configs from a template that already sets `queue.type = "pg-queue"` with a database URL.
Keep Postgres reachable and migrated before invoking queue subcommands.
Separate test configs (in-memory) from ops configs in CI so queue commands never run against in-memory setups.
Assert the queue backend in deployment smoke tests.

When it happens

Trigger: Running `voyager queue enqueue <op>` or any other `queue` subcommand while the config's `queue` field is the default `in-memory` variant (or explicitly set to `{ type = "in-memory" }`).

Common situations: Using a minimal/generated default config that does not configure Postgres; running queue admin commands against a config intended only for testing the relayer in-memory; upgrading voyager after the queue config format changed to the tagged enum and the TOML no longer selects `pg-queue`.

Related errors

AI-assisted analysis of unionlabs/union@031785bb6d (2026-08-16). Data as JSON: /api/errors/60b7f9bcfb1b64c7. Report an issue: GitHub.