## API

These APIs are used to retrieve node metadata and for synchronization between nodes. Some methods are not meant for use by external applications.

| Method Name                       | Request Type                  | Response Type             | Description                                       |
|-----------------------------------|-------------------------------|--------------------------|---------------------------------------------------|
| GetInfo                           | GetInfoRequest                | GetInfoResponse           | Returns metadata about the node’s state          |
| GetTrieMetadataByPrefix           | TrieNodeMetadataRequest       | TrieNodeMetadataResponse | Get trie metadata for a particular prefix         |

## GetInfoRequest

Empty request, no parameters needed.

## GetInfoResponse

| Field          | Type      | Label | Description                      |
|----------------|-----------|-------|----------------------------------|
| db_stats       | [DbStats](https://docs.neynar.com/snapchain/grpcapi/metadata#DbStats) |       | Database statistics               |
| num_shards     | uint32    |       | Number of shards in the node     |
| shard_infos    | ShardInfo | repeated | Information about each shard      |

## DbStats

| Field                     | Type    | Label | Description                            |
|---------------------------|---------|-------|----------------------------------------|
| num_messages              | uint64  |       | Total number of messages in the node   |
| num_fid_registrations     | uint64  |       | Number of FID registrations in the node |
| approx_size               | uint64  |       | Approximate size of the database in bytes |

## ShardInfo

| Field                     | Type    | Label | Description                            |
|---------------------------|---------|-------|----------------------------------------|
| shard_id                  | uint32  |       | Shard identifier                        |
| max_height                | uint64  |       | Maximum block height in the shard      |
| num_messages              | uint64  |       | Number of messages in the shard        |
| num_fid_registrations     | uint64  |       | Number of FID registrations in the shard |
| approx_size               | uint64  |       | Approximate size of the shard in bytes  |
| block_delay               | uint64  |       | Block delay in the shard                |
| mempool_size              | uint64  |       | Size of the mempool for this shard      |

## TrieNodeMetadataRequest

| Field         | Type   | Label | Description                         |
|---------------|--------|-------|-------------------------------------|
| shard_id      | uint32 |       | Shard ID to get metadata for       |
| prefix        | bytes  |       | Prefix to get metadata for         |

## TrieNodeMetadataResponse

| Field         | Type   | Label | Description                              |
|---------------|--------|-------|------------------------------------------|
| prefix        | bytes  |       | Prefix of the trie node                  |
| num_messages  | uint64 |       | Number of messages under this prefix     |
| hash          | string |       | Hash of the trie node                    |
| children      | TrieNodeMetadataResponse | repeated | Child nodes of this trie node          |