Can not decode types with variable length encoding. #181
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Currently subxt can only handle fix-size types. In |
h4x3rotab
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Fixes paritytech#196, paritytech#181, #28 ## Dyanmic sized types Before this change, the event decoder assume all the event types have fixed sizes. Some counterexamples are: Hashes, AuthorityList. In this change, instead of decoding by skipping the fixed-length bytes, we introduce `type_segmenter` registry which decodes the raw event bytes with the actual scale codec. So variable length types can be handled correctly. ## New attribute for pallet type definition In the past, trait associated type is the only way to add types to the EventsDecoder implementation of a pallet. But in reality it's common that the events in a pallet references some types not defined in the trait associated types. Some examples are: `IdentificationTuple` and `SessionIndex` in Session pallet. In this change, we introduce more attributes to add the types: ```rust #[module] trait Pallet: System { #![event_type(SomeType)] #![event_alias(TypeNameAlias = SomeType)] #![event_alias(SomeOtherAlias = TypeWithAssociatedTypes<T>)] } ``` ## Tested Compile with `nightly-2020-10-01`; smoke test to sync a full Phala bockchain.
h4x3rotab
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Jan 14, 2021
Fixes paritytech#196, paritytech#181, #28 ## Dyanmic sized types Before this change, the event decoder assume all the event types have fixed sizes. Some counterexamples are: Hashes, AuthorityList. In this change, instead of decoding by skipping the fixed-length bytes, we introduce `type_segmenter` registry which decodes the raw event bytes with the actual scale codec. So variable length types can be handled correctly. ## New attribute for pallet type definition In the past, trait associated type is the only way to add types to the EventsDecoder implementation of a pallet. But in reality it's common that the events in a pallet references some types not defined in the trait associated types. Some examples are: `IdentificationTuple` and `SessionIndex` in Session pallet. In this change, we introduce more attributes to add the types: ```rust #[module] trait Pallet: System { #![event_type(SomeType)] #![event_alias(TypeNameAlias = SomeType)] #![event_alias(SomeOtherAlias = TypeWithAssociatedTypes<T>)] } ``` ## Tested Compile with `nightly-2020-10-01`; smoke test to sync a full Phala bockchain.
ascjones
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Jan 20, 2021
* Refactor event type decoding hand declartion Fixes #196, #181, #28 ## Dyanmic sized types Before this change, the event decoder assume all the event types have fixed sizes. Some counterexamples are: Hashes, AuthorityList. In this change, instead of decoding by skipping the fixed-length bytes, we introduce `type_segmenter` registry which decodes the raw event bytes with the actual scale codec. So variable length types can be handled correctly. ## New attribute for pallet type definition In the past, trait associated type is the only way to add types to the EventsDecoder implementation of a pallet. But in reality it's common that the events in a pallet references some types not defined in the trait associated types. Some examples are: `IdentificationTuple` and `SessionIndex` in Session pallet. In this change, we introduce more attributes to add the types: ```rust #[module] trait Pallet: System { #![event_type(SomeType)] #![event_alias(TypeNameAlias = SomeType)] #![event_alias(SomeOtherAlias = TypeWithAssociatedTypes<T>)] } ``` ## Tested Compile with `nightly-2020-10-01`; smoke test to sync a full Phala bockchain. * Format code * Make rustfmt::skip an outer attribute * Ignore the sample code * Alias the event segmenter closure * Copy AuthorityList from sp_finality_grandpa * Remove the unused static event type size * Make segmenter as a trait, resue grandpa::Public * Wrap PhantomData in struct TypeMarker
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I have an event that contains a public key as an elliptic curve point, which looks roughly like this:
When I register it using
register_type_size<PublicKey>("PublicKey")*, I can successfully decode events containing Zero values, but non-zero values fail with:On the other hand, if I force the type_size to the second case (which is 65 bytes encoded) using
register_type_size<(u8, [u8;32], [u8;32])>("PublicKey")then I can sucessfully decode non-zero values but the Zero value fails with the above error.How do I get event decoding to work in all cases?
*: PS: I'd like to use the
#[module]macro, but it doesn't allow me to add types other than trait associated ones?The text was updated successfully, but these errors were encountered: