Questions tagged [query]
The query tag has no usage guidance.
16
questions
3
votes
1
answer
38
views
subscriptions with parameters in polkadot.js api
I am using React+Typescript and trying to retrieve data from a struc using a query subscription. I first tried the following in order to check that I'm retrieving the right data:
api.query.rolesModule....
- 385
3
votes
2
answers
54
views
How to perform chain state query for entries AND at a block hash?
I can do this to get all the structs in my storage:
let queryResult = await api.query.mypallet.mystorage.entries();
but I want this query AT a specific block hash:
let currentHeader = ...
- 530
3
votes
1
answer
58
views
Build the data bytes to query a contract with the api state_call
I would like to use the rpc call to query a contract.
I try to use the method "call" from the endpoint "state" with the first parameter "ContractsApi_call" but I am not ...
- 31
4
votes
1
answer
36
views
Listen to balance changes wrong after transfer token
I'm facing an issue. I used a query subscription to listen and update the free balance on UI. But I don't know why, when I log free in callback, they always return a balance of receiver and then a ...
- 61
0
votes
1
answer
55
views
How do you perform a state query in a unit test?
In a custom Substrate pallet unit test, I need to get a list of governance proposals using the chain state. I have used Polkadot JS to query state before but not from within a Substrate unit test in ...
- 530
1
vote
1
answer
56
views
PolkadotJs Api: queryMulti with different blockHashes
Is it possible to do a multiQuery querying multiple types and multiple blockhashes? Even same type and different block hashes would be helpful. Something along the lines of
const multiQueryResult = ...
- 73
2
votes
1
answer
55
views
How to produce empty paramter in an Option?
In the screenshot below the OptionSelect is disabled, which produces info of an array of accounts rather than just one single.
How do you replicate this option when curating a call?
Using api.query....
- 1,366
1
vote
1
answer
128
views
how to replace api.rpc.payment.queryInfo in polkadotjs now that it is deprecated?
In https://github.com/polkadot-js/api/releases/tag/v9.8.2 api.rpc.payment.queryInfo is marked as deprecated but how can you build a transaction through polkadotjs without using it?
- 13
5
votes
0
answers
81
views
How can we expose a runtime constant?
I have a situation where I have a constant defined in my runtime (but not in any pallet) which I want to expose with the runtime itself in some way.
Specifically, there is a constant used as a ...
- 123
1
vote
1
answer
82
views
multi method for api.rpc.chain.getBlockHash does not seem to exist
Could you tell me what is wrong with this code?
Is there a way to achieve multiple query?
<index.mjs>
import { ApiPromise, WsProvider } from '@polkadot/api';
const wsProvider = new WsProvider('...
- 41
2
votes
1
answer
42
views
When querying storage at a particular block, are the values returned those before or after the execution of the extrinsics in that block?
For example:
We have a storage item: Counter that is set to 0. An extrinsic increment in block 11 adds 1 to Counter.
If we query for the value of Counter at block 11, do we get 0 or 1?
- 299
2
votes
1
answer
112
views
How to write a custom query for storage?
When you declare a storage say
pub type Something<T> = StorageValue<_, u32>;
We get query function "something".
But I want to write some specific functions that reads storage ...
- 663
2
votes
1
answer
50
views
How to use the .multi() method? (substrate-front-end-template)
I finished the substrate kitty tutorial (backend and frontend). Now I would like to build a simple frontend for the RMRK pallet. Now I stuck on the .multi(...) method. Where can I find a documentation ...
- 91
4
votes
1
answer
140
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 ...
2
votes
1
answer
199
views
How to determine which parameters are required when using substrate.query() to query a storage_function from polkascan's py-substrate-interface?
When querying storage functions using Polkascan's py-substrate-interface how do you figure out which parameters are required?
For example, I am trying to discern how much KSM is on Karura via storage ...
- 335
2
votes
1
answer
74
views
How do you query a list of all previous block hashes from a substrate based chain?
I can see how to do so from the subscan api but I am interested in understanding how to query this data from the chain itself. Ie via a storage function or by another means
- 335