diff --git a/substrate/frame/support/src/storage/types/double_map.rs b/substrate/frame/support/src/storage/types/double_map.rs index 8e315cef85..3e37c0522e 100644 --- a/substrate/frame/support/src/storage/types/double_map.rs +++ b/substrate/frame/support/src/storage/types/double_map.rs @@ -34,7 +34,7 @@ use sp_std::vec::Vec; /// /// Each value is stored at: /// ```nocompile -/// Twox128(::name()) +/// Twox128(Prefix::pallet_prefix()) /// ++ Twox128(Prefix::STORAGE_PREFIX) /// ++ Hasher1(encode(key1)) /// ++ Hasher2(encode(key2)) @@ -68,8 +68,7 @@ where type Hasher1 = Hasher1; type Hasher2 = Hasher2; fn module_prefix() -> &'static [u8] { - ::name::() - .expect("Every active pallet has a name in the runtime; qed").as_bytes() + Prefix::pallet_prefix().as_bytes() } fn storage_prefix() -> &'static [u8] { Prefix::STORAGE_PREFIX.as_bytes() @@ -415,8 +414,7 @@ mod test { struct Prefix; impl StorageInstance for Prefix { - type Pallet = (); - type PalletInfo = (); + fn pallet_prefix() -> &'static str { "test" } const STORAGE_PREFIX: &'static str = "foo"; } diff --git a/substrate/frame/support/src/storage/types/map.rs b/substrate/frame/support/src/storage/types/map.rs index d28b7dbaa7..64f9ff4b05 100644 --- a/substrate/frame/support/src/storage/types/map.rs +++ b/substrate/frame/support/src/storage/types/map.rs @@ -33,7 +33,7 @@ use sp_std::prelude::*; /// /// Each value is stored at: /// ```nocompile -/// Twox128(::name()) +/// Twox128(Prefix::pallet_prefix()) /// ++ Twox128(Prefix::STORAGE_PREFIX) /// ++ Hasher1(encode(key)) /// ``` @@ -60,8 +60,7 @@ where type Query = QueryKind::Query; type Hasher = Hasher; fn module_prefix() -> &'static [u8] { - ::name::() - .expect("Every active pallet has a name in the runtime; qed").as_bytes() + Prefix::pallet_prefix().as_bytes() } fn storage_prefix() -> &'static [u8] { Prefix::STORAGE_PREFIX.as_bytes() @@ -318,8 +317,7 @@ mod test { struct Prefix; impl StorageInstance for Prefix { - type Pallet = (); - type PalletInfo = (); + fn pallet_prefix() -> &'static str { "test" } const STORAGE_PREFIX: &'static str = "foo"; } diff --git a/substrate/frame/support/src/storage/types/value.rs b/substrate/frame/support/src/storage/types/value.rs index da80963b28..649b7b9fd2 100644 --- a/substrate/frame/support/src/storage/types/value.rs +++ b/substrate/frame/support/src/storage/types/value.rs @@ -31,7 +31,7 @@ use frame_metadata::{DefaultByteGetter, StorageEntryModifier}; /// /// Each value is stored at: /// ```nocompile -/// Twox128(::name()) ++ Twox128(Prefix::STORAGE_PREFIX) +/// Twox128(Prefix::pallet_prefix()) ++ Twox128(Prefix::STORAGE_PREFIX) /// ``` pub struct StorageValue( core::marker::PhantomData<(Prefix, Value, QueryKind, OnEmpty)> @@ -47,8 +47,7 @@ where { type Query = QueryKind::Query; fn module_prefix() -> &'static [u8] { - ::name::() - .expect("Every active pallet has a name in the runtime; qed").as_bytes() + Prefix::pallet_prefix().as_bytes() } fn storage_prefix() -> &'static [u8] { Prefix::STORAGE_PREFIX.as_bytes() @@ -201,8 +200,7 @@ mod test { struct Prefix; impl StorageInstance for Prefix { - type Pallet = (); - type PalletInfo = (); + fn pallet_prefix() -> &'static str { "test" } const STORAGE_PREFIX: &'static str = "foo"; } diff --git a/substrate/frame/support/src/traits.rs b/substrate/frame/support/src/traits.rs index 19c23a464d..1bbcd87cc2 100644 --- a/substrate/frame/support/src/traits.rs +++ b/substrate/frame/support/src/traits.rs @@ -1731,13 +1731,19 @@ pub trait Instance: 'static { const PREFIX: &'static str; } -/// An instance of a storage. +/// An instance of a storage in a pallet. /// -/// It is required the the couple `(PalletInfo::name(), STORAGE_PREFIX)` is unique. -/// Any storage with same couple will collide. +/// Define an instance for an individual storage inside a pallet. +/// The pallet prefix is used to isolate the storage between pallets, and the storage prefix is +/// used to isolate storages inside a pallet. +/// +/// NOTE: These information can be used to define storages in pallet such as a `StorageMap` which +/// can use keys after `twox_128(pallet_prefix())++twox_128(STORAGE_PREFIX)` pub trait StorageInstance { - type Pallet: 'static; - type PalletInfo: PalletInfo; + /// Prefix of a pallet to isolate it from other pallets. + fn pallet_prefix() -> &'static str; + + /// Prefix given to a storage to isolate from other storages in the pallet. const STORAGE_PREFIX: &'static str; }