config: Add SkipCheckIfFeeless signed extension

subxt/examples/setup_config_custom.rs

@@ -3,7 +3,19 @@ use subxt::client::OfflineClientT;
 use subxt::config::{Config, ExtrinsicParams, ExtrinsicParamsEncoder};
 use subxt_signer::sr25519::dev;
 
-#[subxt::subxt(runtime_metadata_path = "../artifacts/polkadot_metadata_full.scale")]
+#[subxt::subxt(
+    runtime_metadata_path = "../artifacts/polkadot_metadata_full.scale",
+    derive_for_type(path = "xcm::v2::multilocation::MultiLocation", derive = "Clone"),
+    derive_for_type(path = "xcm::v2::multilocation::Junctions", derive = "Clone"),
+    derive_for_type(path = "xcm::v2::junction::Junction", derive = "Clone"),
+    derive_for_type(path = "xcm::v2::NetworkId", derive = "Clone"),
+    derive_for_type(path = "xcm::v2::BodyId", derive = "Clone"),
+    derive_for_type(path = "xcm::v2::BodyPart", derive = "Clone"),
+    derive_for_type(
+        path = "bounded_collections::weak_bounded_vec::WeakBoundedVec",
+        derive = "Clone"
+    )
+)]
 pub mod runtime {}
 use runtime::runtime_types::xcm::v2::multilocation::MultiLocation;
 

subxt/examples/setup_config_signed_extension.rs

@@ -1,4 +1,5 @@
 use codec::Encode;
+use scale_encode::EncodeAsType;
 use subxt::client::OfflineClientT;
 use subxt::config::signed_extensions;
 use subxt::config::{
@@ -11,6 +12,7 @@ pub mod runtime {}
 
 // We don't need to construct this at runtime,
 // so an empty enum is appropriate:
+#[derive(EncodeAsType)]
 pub enum CustomConfig {}
 
 impl Config for CustomConfig {
@@ -32,6 +34,10 @@ impl Config for CustomConfig {
             signed_extensions::CheckMortality<Self>,
             signed_extensions::ChargeAssetTxPayment<Self>,
             signed_extensions::ChargeTransactionPayment,
+            signed_extensions::SkipCheckIfFeeless<
+                Self,
+                signed_extensions::ChargeAssetTxPayment<Self>,
+            >,
             // And add a new one of our own:
             CustomSignedExtension,
         ),
@@ -81,8 +87,8 @@ impl ExtrinsicParamsEncoder for CustomSignedExtension {
 pub fn custom(
     params: DefaultExtrinsicParamsBuilder<CustomConfig>,
 ) -> <<CustomConfig as Config>::ExtrinsicParams as ExtrinsicParams<CustomConfig>>::OtherParams {
-    let (a, b, c, d, e, f, g) = params.build();
-    (a, b, c, d, e, f, g, ())
+    let (a, b, c, d, e, f, g, h) = params.build();
+    (a, b, c, d, e, f, g, h, ())
 }
 
 #[tokio::main]

subxt/src/blocks/extrinsic_types.rs

@@ -13,7 +13,7 @@ use crate::{
 };
 
 use crate::config::signed_extensions::{
-    ChargeAssetTxPayment, ChargeTransactionPayment, CheckNonce,
+    ChargeAssetTxPayment, ChargeTransactionPayment, CheckNonce, SkipCheckIfFeeless,
 };
 use crate::config::SignedExtension;
 use crate::dynamic::DecodedValue;
@@ -685,7 +685,7 @@ impl<'a, T: Config> ExtrinsicSignedExtensions<'a, T> {
     ///
     /// Returns `None` if  `tip` was not found or decoding failed.
     pub fn tip(&self) -> Option<u128> {
-        // Note: the overhead of iterating twice should be negligible.
+        // Note: the overhead of iterating multiple time should be negligible.
         self.find::<ChargeTransactionPayment>()
             .ok()
             .flatten()
@@ -696,6 +696,12 @@ impl<'a, T: Config> ExtrinsicSignedExtensions<'a, T> {
                     .flatten()
                     .map(|e| e.tip())
             })
+            .or_else(|| {
+                self.find::<SkipCheckIfFeeless<T, ChargeAssetTxPayment<T>>>()
+                    .ok()
+                    .flatten()
+                    .map(|skip_check| skip_check.inner_signed_extension().tip())
+            })
     }
 
     /// The nonce of the account that submitted the extrinsic, extracted from the CheckNonce signed extension.

subxt/src/config/default_extrinsic_params.rs

@@ -17,6 +17,7 @@ pub type DefaultExtrinsicParams<T> = signed_extensions::AnyOf<
         signed_extensions::CheckMortality<T>,
         signed_extensions::ChargeAssetTxPayment<T>,
         signed_extensions::ChargeTransactionPayment,
+        signed_extensions::SkipCheckIfFeeless<T, signed_extensions::ChargeAssetTxPayment<T>>,
     ),
 >;
 
@@ -131,6 +132,9 @@ impl<T: Config> DefaultExtrinsicParamsBuilder<T> {
         let charge_transaction_params =
             signed_extensions::ChargeTransactionPaymentParams::tip(self.tip);
 
+        let skip_check_params =
+            signed_extensions::SkipCheckIfFeelessParams::from(charge_asset_tx_params.clone());
+
         (
             (),
             (),
@@ -139,6 +143,7 @@ impl<T: Config> DefaultExtrinsicParamsBuilder<T> {
             check_mortality_params,
             charge_asset_tx_params,
             charge_transaction_params,
+            skip_check_params,
         )
     }
 }

subxt/src/config/extrinsic_params.rs

@@ -18,7 +18,19 @@ pub enum ExtrinsicParamsError {
     /// A signed extension was encountered that we don't know about.
     #[error("Error constructing extrinsic parameters: Unknown signed extension '{0}'")]
     UnknownSignedExtension(String),
-    /// Some custom error.
+    /// Cannot find the type id of a signed extension in the metadata.
+    #[error("Cannot find extension's '{0}' type id '{1} in the metadata")]
+    MissingTypeId(String, u32),
+    /// User provided a different signed extension than the one expected.
+    #[error("Provided a different signed extension for '{0}', the metadata expect '{1}'")]
+    ExpectedAnotherExtension(String, String),
+    /// The inner type of a signed extension is not present in the metadata.
+    #[error("The inner type of the signed extension '{0}' is not present in the metadata")]
+    MissingInnerSignedExtension(String),
+    /// The inner type of the signed extension is not named.
+    #[error("The signed extension's '{0}' type id '{1}' does not have a name in the metadata")]
+    ExpectedNamedTypeId(String, u32),
+    /// Some custom error.s
     #[error("Error constructing extrinsic parameters: {0}")]
     Custom(CustomError),
 }

subxt/src/config/mod.rs

@@ -18,6 +18,7 @@ pub mod substrate;
 use codec::{Decode, Encode};
 use core::fmt::Debug;
 use scale_decode::DecodeAsType;
+use scale_encode::EncodeAsType;
 use serde::{de::DeserializeOwned, Serialize};
 
 pub use default_extrinsic_params::{DefaultExtrinsicParams, DefaultExtrinsicParamsBuilder};
@@ -54,7 +55,7 @@ pub trait Config: Sized + Send + Sync + 'static {
     type ExtrinsicParams: ExtrinsicParams<Self>;
 
     /// This is used to identify an asset in the `ChargeAssetTxPayment` signed extension.
-    type AssetId: Debug + Encode + DecodeAsType;
+    type AssetId: Debug + Clone + Encode + DecodeAsType + EncodeAsType;
 }
 
 /// given some [`Config`], this return the other params needed for its `ExtrinsicParams`.