Subscribe to Blocks

Block subscriptions provide real-time access to complete Solana blocks, including all transactions, account updates, and metadata. This is ideal for indexers, analytics platforms, and applications that need comprehensive blockchain data.

Overview

A block contains:

• All transactions included in a slot
• Block metadata (hash, parent, height, etc.)
• Transaction ordering and execution results
• Block rewards
• Commitment status

Block subscriptions give you the complete picture of what happened in each slot.

Filter Structure

message SubscribeRequestFilterBlocks {
    repeated string account_include = 1;
    bool include_transactions = 2;
    bool include_accounts = 3;
    bool include_entries = 4;
}

Filter Options

Account Include

Filter blocks to only those containing transactions that involve specific accounts.

Field: account_include
Type: repeated string

Behavior:

• If empty/unset: Receive all blocks
• If specified: Only receive blocks containing transactions involving at least one of these accounts

Use Cases:

• Index only blocks relevant to specific programs
• Track blocks containing activity for watched accounts
• Reduce data volume by filtering at the source

Include Transactions

Control whether full transaction data is included.

Field: include_transactions
Type: bool
Default: true

When true:

• Full transaction details included in each block
• Larger payload size
• Complete transaction information available

When false:

• Only transaction signatures included
• Smaller payload size
• Useful when you only need block structure

Include Accounts

Control whether account update information is included.

Field: include_accounts
Type: bool
Default: false

When true:

• Account state changes included
• Shows which accounts were modified in each transaction
• Larger payload size

When false:

• No account update information
• Smaller payload size

Include Entries

Control whether entry data is included.

Field: include_entries
Type: bool
Default: false

When true:

• Raw entry data included
• Detailed block construction information
• Largest payload size

When false:

• No entry data
• Smaller payload size

Response Structure

Block updates arrive as SubscribeUpdateBlock messages:

message SubscribeUpdateBlock {
    uint64 slot = 1;
    string blockhash = 2;
    solana.storage.ConfirmedBlock.Rewards rewards = 3;
    solana.storage.ConfirmedBlock.UnixTimestamp block_time = 4;
    solana.storage.ConfirmedBlock.BlockHeight block_height = 5;
    uint64 parent_slot = 7;
    string parent_blockhash = 8;
    uint64 executed_transaction_count = 9;
    repeated SubscribeUpdateTransactionInfo transactions = 6;
    uint64 updated_account_count = 10;
    repeated SubscribeUpdateAccountInfo accounts = 11;
    uint64 entries_count = 12;
    repeated SubscribeUpdateEntry entries = 13;
}

Key Fields

slot: The slot number for this block
blockhash: Unique hash identifying this block
rewards: Validator rewards for this block
block_time: Unix timestamp when block was produced
block_height: Block height in the ledger
parent_slot: Previous slot number
parent_blockhash: Hash of parent block
executed_transaction_count: Number of transactions in this block
transactions: Full transaction details (if include_transactions=true)
updated_account_count: Number of accounts updated in this block
accounts: Account update information (if include_accounts=true)
entries_count: Number of entries in this block
entries: Entry data (if include_entries=true)

Block vs Block Meta

Choose between full blocks and block metadata: