Available streams

Live snapshot of every stream this server is configured to broadcast. Click a tile to copy its network@stream selector. Data sourced from GET /streams.

URL modes

Stream selectors are <network>@<stream>. * is a wildcard on either side. Two ways to connect:

When wrapped, every payload is delivered as:

{ "stream": "<network>@<stream>", "data": <raw payload> }

Bare /ws with no streams returns HTTP 400. Use /ws/*@* to opt into every stream explicitly. See the HTTP group in the sidebar for non-WebSocket endpoints (/streams, /healthz, /SKILL.md, /llms.txt).

Connected message

Sent once per connection. Lists every configured stream and echoes this connection's resolved subscriptions.

{
  "type": "session",
  "status": "connected",
  "client_id": 1,
  "streams": [
    {
      "stream": "swaps",
      "network": "solana-mainnet",
      "module": "db_out",
      "manifest": "https://.../svm-dex-v0.5.1.spkg",
      "module_hash": "bd388f2e39f5dcc237cfbdb8d6c96d9e5678c797"
    }
  ],
  "subscriptions": ["solana-mainnet@swaps"],
  "wrap_envelope": false
}

Block payload

One message per non-empty block. Empty blocks are skipped; their cursor is still persisted server-side.

{
  "stream":      "swaps",
  "network":     "solana-mainnet",
  "block_num":   350000000,
  "block_hash":  "Gsk6...",
  "timestamp":   "2026-05-13 17:00:00",
  "cursor":      "Mloz_-WpoBoZ...",
  "module_hash": "bd388f2e...",
  "events": [
    {
      "@table":        "swaps",
      "input_amount":  "1287000000",
      "input_mint":    "So11111111111111111111111111111111111111112",
      "output_amount": "6848381008732",
      "output_mint":   "13muFY...",
      "protocol":      "raydium_cpmm",
      "user":          "F2MUE..."
    }
  ]
}

Field rules:

• @table identifies the source table per row. Prefixed so a real column literally named table can't shadow it.
• Field values inside events[*] are strings on the wire (per DatabaseChanges proto). Numeric parsing is the consumer's job.
• Row-level keys that duplicate top-level meta (block_num, block_hash, timestamp, minute) are stripped.
• Upstream ordinal, operation, pk/composite_pk, update_op are dropped.

Stream lifecycle

Same connection, distinguished by "type": "stream". Filtered by subscriptions just like block payloads.

{ "type": "stream", "status": "started",   ... }
{ "type": "stream", "status": "completed", ... }
{ "type": "stream", "status": "error",     ..., "message": "..." }
{ "type": "stream", "status": "fatal",     ..., "message": "..." }
{ "type": "stream", "status": "undo",      ..., "last_valid_block": 350000000 }

undo fires on chain reorganizations. Roll back any state materialized past last_valid_block.

SUBSCRIBE

Add to the per-connection subscription set. Idempotent.

// request
{ "method": "SUBSCRIBE",
  "params": ["solana-mainnet@swaps", "ethereum-mainnet@transfers"],
  "id": 1 }

// reply
{ "result": null, "id": 1 }

Wildcards accepted (["*@swaps"]). A single bad selector rejects the whole command — existing set unchanged. The wrap_envelope mode is fixed at upgrade time and is not affected by SUBSCRIBE.

UNSUBSCRIBE

Remove from the subscription set. Silent on unknown selectors.

// request
{ "method": "UNSUBSCRIBE",
  "params": ["ethereum-mainnet@transfers"],
  "id": 2 }

// reply
{ "result": null, "id": 2 }

To remove a wildcard subscription, pass the exact wildcard form (*@swaps removes the wildcard entry, not the individual streams it currently matches).

LIST_SUBSCRIPTIONS

Inspect the current subscription set.

// request
{ "method": "LIST_SUBSCRIPTIONS", "id": 3 }

// reply
{ "result": ["solana-mainnet@swaps", "ethereum-mainnet@*"], "id": 3 }

Insertion order preserved. Wildcards returned verbatim, not expanded.

Cursors

Every block payload includes cursor. To resume from an exact position across reconnects, persist the last cursor you processed and reconnect to a Substreams gRPC endpoint directly with it — this server has no replay buffer.

Heartbeats

The server sends WebSocket ping frames every SUBSTREAMS_WEBSOCKET_HEARTBEAT_INTERVAL_SECS seconds (default 180s). Standard WebSocket clients pong automatically. The server closes connections that do not pong within SUBSTREAMS_WEBSOCKET_HEARTBEAT_TIMEOUT_SECS seconds (default 600s).

Limits

• No replay buffer. Disconnected clients miss broadcasts during the gap.
• One output type. Only sf.substreams.sink.database.v1.DatabaseChanges.
• Per-connection client buffer. Slow consumers are dropped per-message rather than blocking the ingest loop. Defaults to 1024 messages, configurable via SUBSTREAMS_WEBSOCKET_CLIENT_BUFFER_SIZE.