The IBC Rate Limit module provides a minimal middleware interface for forwarding IBC packet information to a CosmWasm contract.
CLI Implementation Issue: The current CLI implementation has a bug that prevents query commands from working. Use REST endpoints instead.

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Parameters

ParameterTypeDescription
contract_addressstringAddress of the CosmWasm contract that handles rate limiting decisions. Empty string disables rate limiting.

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Queries

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QueryParams

Retrieve the current module parameters. REST: 
GET /neutron/ibc-rate-limit/v1beta1/params
Response: 
{
  "params": {
    "contract_address": "neutron1abcdef..."
  }
}

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Messages

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MsgUpdateParams

Update module parameters through governance. Authority Required: Governance only Fields:
  • authority: Governance authority address
  • params: New module parameters containing the contract address
Example: 
{
  "@type": "/neutron.ibcratelimit.v1beta1.MsgUpdateParams",
  "authority": "neutron10d07y265gmmuvt4z0w9aw880jnsr700j7g7ejq",
  "params": {
    "contract_address": "neutron1newaddress..."
  }
}

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Events

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EventBadRevert

Emitted when the module fails to notify the contract about a failed packet. Type: bad_revert Attributes:
  • module: rate-limited-ibc
  • failure_type: Type of failure (acknowledgment or timeout)
  • packet: The IBC packet data
  • acknowledgement: The acknowledgement data (only present for acknowledgment failures)

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Error Types

The module defines these error types:
ErrorCodeDescription
ErrRateLimitExceeded2Returned when the contract rejects a transfer due to rate limits
ErrBadMessage3Returned for malformed packet data
ErrContractError4Returned for other contract execution errors

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Contract Interface

The module sends standardized sudo messages to the configured contract:

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send_packet

Sent when an IBC packet is being transmitted from Neutron. Message Structure: 
{
  "send_packet": {
    "packet": {
      "sequence": 0,
      "source_port": "transfer",
      "source_channel": "channel-0",
      "destination_port": "omitted",
      "destination_channel": "omitted",
      "data": {
        "denom": "untrn",
        "amount": "1000000",
        "sender": "neutron1...",
        "receiver": "cosmos1..."
      },
      "timeout_height": {},
      "timeout_timestamp": 0
    }
  }
}

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recv_packet

Sent when an IBC packet is being received by Neutron. Message Structure: 
{
  "recv_packet": {
    "packet": {
      // Same structure as send_packet
    }
  }
}

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undo_send

Sent when a packet send fails and needs to be reverted. Message Structure: 
{
  "undo_send": {
    "packet": {
      // Same structure as send_packet
    }
  }
}

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Module Behavior

  • No Contract Set: If contract_address is empty, all transfers proceed without rate limiting
  • Contract Set: All transfers are forwarded to the contract for approval
  • Rate Limit Detection: Contract errors containing the substring “rate limit exceeded” return ErrRateLimitExceeded
  • Other Contract Errors: All other contract errors return ErrContractError
  • Failed Packet Handling: Automatically calls undo_send for timeouts and error acknowledgments
Contract Independence: The module does not implement any rate limiting logic itself. All rate limiting behavior depends entirely on the CosmWasm contract implementation.