Substreams WebSockets service — stream decoded blocks, swaps & transfers in real time.
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    EVTsession welcome

    Sent once per connection. Describes every stream the server is configured to broadcast, and echoes the subscriptions this connection actually resolved to.

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

    Fields

    typestring

    Always "session".

    statusstring

    "connected" on a healthy upgrade.

    client_idnumber

    Per-connection id, echoed back for debugging.

    streamsarray

    Every Substreams source the server reads, advertised regardless of your subscription (fields below). Lets a client build a discovery UI without waiting for blocks.

    subscriptionsstring[]

    The filtered set this connection actually receives, as <network>@<table> selectors.

    wrap_envelopeboolean

    Whether subsequent payloads are wrapped in { "stream", "data" } or sent raw. Fixed at upgrade time.

    streams[] entry

    networkstring

    Chain identifier the source streams.

    modulestring

    Output module name (the spkg's db_out).

    manifeststring

    URL of the .spkg the server runs.

    module_hashstring

    40-hex SHA-1 of the output module. Pin it to detect spkg upgrades.

    package_namestring

    Substreams package name.

    package_versionstring

    Substreams package version.

    tablesstring[]

    DatabaseChanges tables this spkg emits — subscribe to any as <network>@<table>.