ImOnline

---

Calls

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heartbeat

## Complexity: - O(K + E) where K is length of Keys (heartbeat.validators_len) and E is length of heartbeat.network_state.external_address - O(K): decoding of length K - O(E): decoding/encoding of length E

Attributes

Name	Type
heartbeat	Heartbeat<T::BlockNumber>
signature	<T::AuthorityId as RuntimeAppPublic>::Signature

Python

call = substrate.compose_call(
    'ImOnline', 'heartbeat', {
    'heartbeat': {
        'authority_index': 'u32',
        'block_number': 'u32',
        'network_state': {
            'external_addresses': [
                'Bytes',
            ],
            'peer_id': 'Bytes',
        },
        'session_index': 'u32',
        'validators_len': 'u32',
    },
    'signature': '[u8; 64]',
}
)

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Events

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AllGood

At the end of the session, no offence was committed.

Attributes

No attributes

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HeartbeatReceived

A new heartbeat was received from AuthorityId.

Attributes

Name	Type	Composition
authority_id	T::AuthorityId	[u8; 32]

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SomeOffline

At the end of the session, at least one validator was found to be offline.

Attributes

Name	Type	Composition
offline	Vec<IdentificationTuple<T>>	[('AccountId', {'total': 'u128', 'own': 'u128', 'others': [{'who': 'AccountId', 'value': 'u128'}]})]

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Storage functions

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AuthoredBlocks

For each session index, we keep a mapping of ValidatorId<T> to the number of blocks authored by the given authority.

Python

result = substrate.query(
    'ImOnline', 'AuthoredBlocks', ['u32', 'AccountId']
)

Return value

'u32'

---

HeartbeatAfter

The block number after which it's ok to send heartbeats in the current session.

At the beginning of each session we set this to a value that should fall roughly in the middle of the session duration. The idea is to first wait for the validators to produce a block in the current session, so that the heartbeat later on will not be necessary.

This value will only be used as a fallback if we fail to get a proper session progress estimate from NextSessionRotation, as those estimates should be more accurate then the value we calculate for HeartbeatAfter.

Python

result = substrate.query(
    'ImOnline', 'HeartbeatAfter', []
)

Return value

'u32'

---

Keys

The current set of keys that may issue a heartbeat.

Python

result = substrate.query(
    'ImOnline', 'Keys', []
)

Return value

['[u8; 32]']

---

ReceivedHeartbeats

For each session index, we keep a mapping of SessionIndex and AuthIndex to WrapperOpaque<BoundedOpaqueNetworkState>.

Python

result = substrate.query(
    'ImOnline', 'ReceivedHeartbeats', ['u32', 'u32']
)

Return value

('u32', {'external_addresses': ['Bytes'], 'peer_id': 'Bytes'})

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Constants

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UnsignedPriority

A configuration for base priority of unsigned transactions.

This is exposed so that it can be tuned for particular runtime, when multiple pallets send unsigned transactions.

Value

18446744073709551615

Python

constant = substrate.get_constant('ImOnline', 'UnsignedPriority')

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Errors

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DuplicatedHeartbeat

Duplicated heartbeat.

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InvalidKey

Non existent public key.

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