Questions tagged [events]
Questions that relate to pallets and disptachables that emit specific events, including decoding events.
34
questions
1
vote
2
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47
views
Why are events stored?
The documentation around emitting events states that events are written to storage, and then cleared next block.
This has considerable costs
You add extra db write/read overhead to practically every ...
- 131
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vote
1
answer
24
views
How do I get the block hash of an event?
I am subscribing system events using the events api. After I got the specific event I am looking for, how should get the block hash of this event?
Thanks
api.query.system.events((events) => {
...
- 13
1
vote
0
answers
14
views
how to confirm a event type?
I query all events, and decode the event a known type, but maybe some write them cause error, how to parse the event
pub fn decode_event(data: &str) -> Result<String> {
let mut vec = ...
- 11
0
votes
1
answer
20
views
GSRPC: Check transaction failed?
Context: We are using GSRPC for interacting with a Polkadot Node. We are sending transactions using SubmitAndWatchExtrinsic.
Question: How can I detect if the transaction failed?
Note: I am aware ...
- 1
1
vote
1
answer
11
views
Will the event pairs `NewMultisig` <> `Reserved` and `MultisigExecuted` <> `Unreserved` always be emitted during a multisig transaction?
I would like to correctly monitor the events that are related to multisig transactions and I was wondering if I should always expect the following event pairs :
NewMultisig <> Reserved
...
- 867
1
vote
2
answers
23
views
Parse block number from received system event
This seems very basic, but I'm unable to figure out at which block number an event was emitted.
Specifically, I'm listening for Grandpa.NewAuthorities system event and just want to know at which block ...
0
votes
1
answer
32
views
How can a recoverable account get notified when someone is initiated a recovery for it?
One of the interesting features of (social) account recovery in Kusama is that "If some one tries to initiate recovery for your recoverable account, you can close the process and kind of punish ...
- 397
0
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0
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33
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From the parachain, how to read the relay chain events of a current block?
From this comment and this question,
There's a function for runtime-benchmarks to get all the events(). And I want something similar that can be accessed from the parachain. Just events from the relay ...
- 33
2
votes
0
answers
32
views
Emit Events from hooks like on_initialize()
Is it okay to emit event from hooks like on_initialize() ?
For example I have ~1000 items in storage and in a loop in on_initialize() I want to emit event if certain process is completed then is it ...
- 91
2
votes
1
answer
32
views
How can I access custom pallet Event data in a test?
I have an Event (ThingStored) that is deposited in a public function in my custom pallet.
#[derive(Encode, Decode, PartialEq, Clone, RuntimeDebugNoBound, TypeInfo, MaxEncodedLen)]
#[scale_info(...
- 179
3
votes
1
answer
61
views
Emiting events does not work with cross contract calling
When using cross contract calling on another contract which also emits
events the events of the original contract do not work anymore.
I get the following error.
error[E0283]: type annotations needed
...
- 87
0
votes
1
answer
34
views
How to assert deposited event in pallet call?
In testing my pallet, I have some function that stores something and deposits an event.
#[pallet::event]
#[pallet::generate_deposit(pub(super) fn deposit_event)]
pub enum Event<T: ...
- 179
2
votes
1
answer
33
views
How to recognise user behaviour data on substrate chains? (Events + Extrinsics)
Context: Specifically trying to measure user behaviour data on substrate chains.
Questions:
Is there any specific data that indicates whether a user triggered an extrinsic or an event?
Do only ...
- 123
1
vote
1
answer
36
views
Subscribing events from Polkadot blockchain
I would like to ask you how to subscribe events from Polkadot blockchain?
I am writing a rust application and I need this functionality there.
Is the using Substrate the right direction to achieve ...
- 13
1
vote
1
answer
36
views
Filter events for specific account in Polkadot.js/api
I am trying to get list events by filter for specific account(validator, nominator).
I can get list of events using api.query.system.events(). However, if I get events for a day, there
will be much ...
- 87
3
votes
1
answer
106
views
Browse events in Polkadot.js/api
I want to get events list by using polkadot.js/api.
I can see api.query.system.events() in docs.
Docs: https://polkadot.js.org/docs/substrate/storage#eventcount-u32
However, this api lists events for ...
- 87
4
votes
2
answers
157
views
Events in Polkadot.js/api
I am trying to call api.events.staking.Withdrawn.is in polkadot.js/api.
Docs: https://polkadot.js.org/docs/substrate/events#withdrawnaccountid32-u128
Code sandbox: https://codesandbox.io/s/hardcore-...
- 87
2
votes
1
answer
234
views
Decoding events with Rust
If I make a request to get events in a particular block using web UI, I get a nice human-readable response:
I've made an RPC call to get the same data
{
"id": 1,
"jsonrpc":...
- 400
2
votes
1
answer
51
views
How to emit events from inner contracts
let's say we have a contract which calls other contract's function that emits an event. What is the approach to emit the event coming from the inner contract's message?
Currently, there is only an ...
- 53
2
votes
1
answer
61
views
Event type & Call type
I am doing Substrate-tutorial and I just have a question about template-node.
Inside impl 'frame_system::Config for Runtime {} code, there are type Event = Event and type Call = Call, but I don't see ...
- 39
0
votes
1
answer
20
views
getReadProof for specific event
I want to generate a StorageProof for a specific event that is stored in storage. I have found System_Events but this returns me all events of a block, instead of a specific one. I stumbled on ...
1
vote
1
answer
49
views
What's the Substrate's equivalent of receipts in Ethereum?
I want to check if a given extrinsic is executed successfully or not from a light client inside the enclave (aka Intel SGX). I am importing new blocks, iterating over the extrinsics I am interested in,...
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6
votes
2
answers
74
views
Should events only be emitted in extrinsics?
Suppose my pallet implements a trait MyTrait so that it can be loosely coupled with another pallet. Suppose also that MyTrait::my_function() makes storage modifications, which I would like to notify ...
- 411
5
votes
2
answers
66
views
Are there any event patterns for pallets to communicate within the runtime?
Could I have one pallet emit an event that other pallets are aware of?
For example:
assets-pallet emits an AssetCreated event
market-pallet listens for the AssetCreated event
So the assets-pallet is ...
3
votes
2
answers
51
views
How to build prefixed key for rocksdb
I would like to know how can the key for the state System Events storage can be built for a given block hash/height
- 31
1
vote
1
answer
37
views
Problem running assert_last_event in tests.rs
As the title suggests, I've been trying to call assert_last_event on the tests.rs class without success. The problem first happened when developing the kitties tutorial and after several toolchain ...
- 13
4
votes
2
answers
61
views
How to parse/match a specific frame_system event?
From the following function I can read the frame_system events:
let events = frame_system::Pallet::<T>::read_events_no_consensus();
the above provides me the following example array:
...
- 592
5
votes
2
answers
58
views
how to verify upward teleport on relay chain
I performed an upward teleport from Encointer parachain to Kusama relaychain.
The parachain confirmed the XCM extrinsic polkadotXcm.limitedTeleportAssets and an Event was disposed: polkadotXcm....
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4
votes
2
answers
46
views
error[E0599]: no function or associated item named `events` found for struct `frame_system::Pallet` in the current scope [closed]
When writing:
let events = frame_system::Pallet::<T>::events();
I get the error:
error[E0599]: no function or associated item named `events` found for struct `frame_system::Pallet` in the ...
- 592
0
votes
1
answer
41
views
What does the Staking.EraPaid event mean?
According to Polkadot's events description page, the Staking.EraPaid event means the following:
The era payout has been set; the first balance is the validator-payout; the second is the remainder ...
5
votes
1
answer
56
views
Filter Events with subxt over multiple threads
I'm working on a project that uses Substrate in the backend. The System I am working on is written with Elixir and so I have a rustler NIF (Erlang/Elixir Native Function interface) for interacting ...
- 53
2
votes
2
answers
120
views
How to decode smart contract call and event data?
I want to decode the contract call data and event data saved in a block. How can I do that?
- 739
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1
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34
views
Which data to put in a Pallet Event?
In other blockchains I practiced extreme frugality with event data, since it is expensive.
For example only putting an ID into an event which can then be looked up with lookup(ID) -> ...
- 2,715
4
votes
1
answer
69
views
Correlate events with extrinsics in a utility.batch call in Polkadot
In Polkadot and Kusama emitted module events has the phase property so we can correlate them with the extrinsic that triggered that event but I can not do the same when the extrinsic is included in a ...
