From b39ff1771ab1486d9fb09984794b46f5218b8126 Mon Sep 17 00:00:00 2001
From: Andrew Jones <ascjones@gmail.com>
Date: Fri, 15 Nov 2019 15:04:06 +0000
Subject: [PATCH] New substrate signing API, srml -> paint rename (#33)

* Update jsonrpc to align with substrate

* Update to new substrate signing

* Default to MultiSignature

* Add missing event type sizes

* Rename TakeFees check to ChargeTransactionPayment

* Fix extrinsic Signature

* Ignore AuthorityList type size

* Rename srml to paint (#32)
---
 Cargo.toml                       | 12 ++---
 src/events.rs                    |  8 ++-
 src/extrinsic.rs                 | 30 +++++++-----
 src/lib.rs                       | 83 ++++++++++++++++++--------------
 src/{srml => paint}/balances.rs  | 27 +++++++----
 src/{srml => paint}/contracts.rs | 31 +++++++-----
 src/{srml => paint}/mod.rs       |  0
 src/{srml => paint}/system.rs    | 29 ++++++-----
 src/rpc.rs                       |  6 +--
 src/runtimes.rs                  |  4 +-
 10 files changed, 136 insertions(+), 94 deletions(-)
 rename src/{srml => paint}/balances.rs (83%)
 rename src/{srml => paint}/contracts.rs (81%)
 rename src/{srml => paint}/mod.rs (100%)
 rename src/{srml => paint}/system.rs (83%)

diff --git a/Cargo.toml b/Cargo.toml
index c021cd5caa..0e8a0da9cc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,15 +19,15 @@ futures = "0.1.28"
 jsonrpc-core-client = { version = "14.0", features = ["ws"] }
 num-traits = { version = "0.2", default-features = false }
 parity-scale-codec = { version = "1.0", default-features = false, features = ["derive", "full"] }
-runtime_metadata = { git = "https://github.com/paritytech/substrate/", package = "srml-metadata" }
-runtime_support = { git = "https://github.com/paritytech/substrate/", package = "srml-support" }
+runtime_metadata = { git = "https://github.com/paritytech/substrate/", package = "paint-metadata" }
+runtime_support = { git = "https://github.com/paritytech/substrate/", package = "paint-support" }
 runtime_primitives = { git = "https://github.com/paritytech/substrate/", package = "sr-primitives" }
 serde = { version = "1.0", features = ["derive"] }
 sr-version = { git = "https://github.com/paritytech/substrate/", package = "sr-version" }
-srml-system = { git = "https://github.com/paritytech/substrate/", package = "srml-system" }
-srml-balances = { git = "https://github.com/paritytech/substrate/", package = "srml-balances" }
-srml-contracts = { git = "https://github.com/paritytech/substrate/", package = "srml-contracts" }
-srml-indices = { git = "https://github.com/paritytech/substrate/", package = "srml-indices" }
+paint-system = { git = "https://github.com/paritytech/substrate/", package = "paint-system" }
+paint-balances = { git = "https://github.com/paritytech/substrate/", package = "paint-balances" }
+paint-contracts = { git = "https://github.com/paritytech/substrate/", package = "paint-contracts" }
+paint-indices = { git = "https://github.com/paritytech/substrate/", package = "paint-indices" }
 substrate-rpc-api = { git = "https://github.com/paritytech/substrate/", package = "substrate-rpc-api" }
 substrate-rpc-primitives = { git = "https://github.com/paritytech/substrate/", package = "substrate-rpc-primitives" }
 substrate-primitives = { git = "https://github.com/paritytech/substrate/", package = "substrate-primitives" }
diff --git a/src/events.rs b/src/events.rs
index fbfe863d36..838f8a5439 100644
--- a/src/events.rs
+++ b/src/events.rs
@@ -20,7 +20,7 @@ use crate::{
         Metadata,
         MetadataError,
     },
-    srml::balances::Balances,
+    paint::balances::Balances,
     System,
     SystemEvent,
 };
@@ -34,7 +34,7 @@ use parity_scale_codec::{
     Input,
     Output,
 };
-use srml_system::Phase;
+use paint_system::Phase;
 use std::{
     collections::{
         HashMap,
@@ -113,8 +113,12 @@ impl<T: System + Balances + 'static> TryFrom<Metadata> for EventsDecoder<T> {
         // Ignore these unregistered types, which are not fixed size primitives
         decoder.check_missing_type_sizes(vec![
             "DispatchError",
+            "Result<(), DispatchError>",
             "OpaqueTimeSlot",
             "rstd::marker::PhantomData<(AccountId, Event)>",
+            // FIXME: determine type size for the following if necessary/possible
+            "IdentificationTuple",
+            "AuthorityList",
         ])?;
         Ok(decoder)
     }
diff --git a/src/extrinsic.rs b/src/extrinsic.rs
index 2af7dc072a..64a3c065b3 100644
--- a/src/extrinsic.rs
+++ b/src/extrinsic.rs
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with substrate-subxt.  If not, see <http://www.gnu.org/licenses/>.
 
-use crate::srml::{
+use crate::paint::{
     balances::Balances,
     system::System,
 };
@@ -29,14 +29,18 @@ use runtime_primitives::{
         SignedPayload,
         UncheckedExtrinsic,
     },
-    traits::SignedExtension,
+    traits::{
+        Verify,
+        IdentifyAccount,
+        SignedExtension,
+    },
     transaction_validity::TransactionValidityError,
 };
 use std::marker::PhantomData;
 use substrate_primitives::Pair;
 
 /// SignedExtra checks copied from substrate, in order to remove requirement to implement
-/// substrate's `srml_system::Trait`
+/// substrate's `paint_system::Trait`
 
 /// Ensure the runtime version registered in the transaction is the same as at present.
 ///
@@ -168,9 +172,9 @@ where
 /// Require the transactor pay for themselves and maybe include a tip to gain additional priority
 /// in the queue.
 #[derive(Encode, Decode, Clone, Eq, PartialEq, Debug)]
-pub struct TakeFees<T: Balances>(#[codec(compact)] T::Balance);
+pub struct ChargeTransactionPayment<T: Balances>(#[codec(compact)] T::Balance);
 
-impl<T> SignedExtension for TakeFees<T>
+impl<T> SignedExtension for ChargeTransactionPayment<T>
 where
     T: Balances + Send + Sync,
 {
@@ -234,7 +238,7 @@ impl<T: System + Balances + Send + Sync> SignedExtra<T> for DefaultExtra<T> {
         CheckEra<T>,
         CheckNonce<T>,
         CheckWeight<T>,
-        TakeFees<T>,
+        ChargeTransactionPayment<T>,
         CheckBlockGasLimit<T>,
     );
 
@@ -245,7 +249,7 @@ impl<T: System + Balances + Send + Sync> SignedExtra<T> for DefaultExtra<T> {
             CheckEra((Era::Immortal, PhantomData), self.genesis_hash),
             CheckNonce(self.nonce),
             CheckWeight(PhantomData),
-            TakeFees(<T as Balances>::Balance::default()),
+            ChargeTransactionPayment(<T as Balances>::Balance::default()),
             CheckBlockGasLimit(PhantomData),
         )
     }
@@ -265,28 +269,30 @@ impl<T: System + Balances + Send + Sync> SignedExtension for DefaultExtra<T> {
     }
 }
 
-pub fn create_and_sign<T: System + Send + Sync, C, P, E>(
+pub fn create_and_sign<T: System + Send + Sync, C, P, S, E>(
     signer: P,
     call: C,
     extra: E,
 ) -> Result<
-    UncheckedExtrinsic<T::Address, C, P::Signature, <E as SignedExtra<T>>::Extra>,
+    UncheckedExtrinsic<T::Address, C, S, <E as SignedExtra<T>>::Extra>,
     TransactionValidityError,
 >
 where
     P: Pair,
-    P::Public: Into<T::Address>,
-    P::Signature: Codec,
+    S: Verify + Codec + From<P::Signature>,
+    S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
     C: Encode,
     E: SignedExtra<T> + SignedExtension,
+    T::Address: From<T::AccountId>,
 {
     let raw_payload = SignedPayload::new(call, extra.extra())?;
     let signature = raw_payload.using_encoded(|payload| signer.sign(payload));
     let (call, extra, _) = raw_payload.deconstruct();
+    let account_id = S::Signer::from(signer.public()).into_account();
 
     Ok(UncheckedExtrinsic::new_signed(
         call,
-        signer.public().into(),
+        account_id.into(),
         signature.into(),
         extra,
     ))
diff --git a/src/lib.rs b/src/lib.rs
index c473b41556..65f66ed0b0 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -32,7 +32,14 @@ use parity_scale_codec::{
     Codec,
     Decode,
 };
-use runtime_primitives::generic::UncheckedExtrinsic;
+use runtime_primitives::{
+    generic::UncheckedExtrinsic,
+    traits::{
+        Verify,
+        IdentifyAccount,
+    },
+    MultiSignature,
+};
 use sr_version::RuntimeVersion;
 use std::{
     convert::TryFrom,
@@ -61,7 +68,7 @@ use crate::{
         MapStream,
         Rpc,
     },
-    srml::{
+    paint::{
         balances::Balances,
         system::{
             System,
@@ -79,25 +86,25 @@ mod extrinsic;
 mod metadata;
 mod rpc;
 mod runtimes;
-mod srml;
+mod paint;
 
 pub use error::Error;
 pub use events::RawEvent;
 pub use rpc::ExtrinsicSuccess;
 pub use runtimes::*;
-pub use srml::*;
+pub use paint::*;
 
 fn connect<T: System>(url: &Url) -> impl Future<Item = Rpc<T>, Error = Error> {
     ws::connect(url).map_err(Into::into)
 }
 
 /// ClientBuilder for constructing a Client.
-pub struct ClientBuilder<T: System> {
-    _marker: std::marker::PhantomData<T>,
+pub struct ClientBuilder<T: System, S = MultiSignature> {
+    _marker: std::marker::PhantomData<(T, S)>,
     url: Option<Url>,
 }
 
-impl<T: System> ClientBuilder<T> {
+impl<T: System, S> ClientBuilder<T, S> {
     /// Creates a new ClientBuilder.
     pub fn new() -> Self {
         Self {
@@ -113,7 +120,7 @@ impl<T: System> ClientBuilder<T> {
     }
 
     /// Creates a new Client.
-    pub fn build(self) -> impl Future<Item = Client<T>, Error = Error> {
+    pub fn build(self) -> impl Future<Item = Client<T, S>, Error = Error> {
         let url = self.url.unwrap_or_else(|| {
             Url::parse("ws://127.0.0.1:9944").expect("Is valid url; qed")
         });
@@ -126,6 +133,7 @@ impl<T: System> ClientBuilder<T> {
                         genesis_hash,
                         metadata,
                         runtime_version,
+                        _marker: PhantomData,
                     }
                 })
         })
@@ -133,25 +141,28 @@ impl<T: System> ClientBuilder<T> {
 }
 
 /// Client to interface with a substrate node.
-pub struct Client<T: System> {
+pub struct Client<T: System, S = MultiSignature> {
     url: Url,
     genesis_hash: T::Hash,
     metadata: Metadata,
     runtime_version: RuntimeVersion,
+    _marker: PhantomData<fn() -> S>,
 }
 
-impl<T: System> Clone for Client<T> {
+impl<T: System, S> Clone for Client<T, S> {
     fn clone(&self) -> Self {
         Self {
             url: self.url.clone(),
             genesis_hash: self.genesis_hash.clone(),
             metadata: self.metadata.clone(),
             runtime_version: self.runtime_version.clone(),
+            _marker:PhantomData,
         }
     }
 }
 
-impl<T: System + Balances + 'static> Client<T> {
+impl<T: System + Balances + 'static, S: 'static> Client<T, S>
+{
     fn connect(&self) -> impl Future<Item = Rpc<T>, Error = Error> {
         connect(&self.url)
     }
@@ -234,16 +245,18 @@ impl<T: System + Balances + 'static> Client<T> {
         &self,
         signer: P,
         nonce: Option<T::Index>,
-    ) -> impl Future<Item = XtBuilder<T, P>, Error = Error>
+    ) -> impl Future<Item = XtBuilder<T, P, S>, Error = Error>
     where
         P: Pair,
-        P::Public: Into<T::AccountId> + Into<T::Address>,
         P::Signature: Codec,
+        S: Verify,
+        S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
     {
         let client = self.clone();
+        let account_id = S::Signer::from(signer.public()).into_account();
         match nonce {
             Some(nonce) => Either::A(future::ok(nonce)),
-            None => Either::B(self.account_nonce(signer.public().into())),
+            None => Either::B(self.account_nonce(account_id)),
         }
         .map(|nonce| {
             let genesis_hash = client.genesis_hash.clone();
@@ -267,8 +280,8 @@ pub enum Valid {}
 pub enum Invalid {}
 
 /// Transaction builder.
-pub struct XtBuilder<T: System, P, V = Invalid> {
-    client: Client<T>,
+pub struct XtBuilder<T: System, P, S, V = Invalid> {
+    client: Client<T, S>,
     nonce: T::Index,
     runtime_version: RuntimeVersion,
     genesis_hash: T::Hash,
@@ -277,7 +290,7 @@ pub struct XtBuilder<T: System, P, V = Invalid> {
     marker: PhantomData<fn() -> V>,
 }
 
-impl<T: System + Balances + 'static, P, V> XtBuilder<T, P, V>
+impl<T: System + Balances + 'static, P, S: 'static, V> XtBuilder<T, P, S, V>
 where
     P: Pair,
 {
@@ -292,19 +305,19 @@ where
     }
 
     /// Sets the nonce to a new value.
-    pub fn set_nonce(&mut self, nonce: T::Index) -> &mut XtBuilder<T, P, V> {
+    pub fn set_nonce(&mut self, nonce: T::Index) -> &mut XtBuilder<T, P, S, V> {
         self.nonce = nonce;
         self
     }
 
     /// Increment the nonce
-    pub fn increment_nonce(&mut self) -> &mut XtBuilder<T, P, V> {
+    pub fn increment_nonce(&mut self) -> &mut XtBuilder<T, P, S, V> {
         self.set_nonce(self.nonce() + 1.into());
         self
     }
 
     /// Sets the module call to a new value
-    pub fn set_call<F>(&self, module: &'static str, f: F) -> XtBuilder<T, P, Valid>
+    pub fn set_call<F>(&self, module: &'static str, f: F) -> XtBuilder<T, P, S, Valid>
     where
         F: FnOnce(ModuleCalls<T, P>) -> Result<Encoded, MetadataError>,
     {
@@ -326,11 +339,12 @@ where
     }
 }
 
-impl<T: System + Balances + Send + Sync + 'static, P> XtBuilder<T, P, Valid>
+impl<T: System + Balances + Send + Sync + 'static, P, S: 'static> XtBuilder<T, P, S, Valid>
 where
     P: Pair,
-    P::Public: Into<T::Address>,
-    P::Signature: Codec,
+    S: Verify + Codec + From<P::Signature>,
+    S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
+    T::Address: From<T::AccountId>,
 {
     /// Creates and signs an Extrinsic for the supplied `Call`
     pub fn create_and_sign(
@@ -339,15 +353,11 @@ where
         UncheckedExtrinsic<
             T::Address,
             Encoded,
-            P::Signature,
+            S,
             <DefaultExtra<T> as SignedExtra<T>>::Extra,
         >,
         Error,
     >
-    where
-        P: Pair,
-        P::Public: Into<T::Address>,
-        P::Signature: Codec,
     {
         let signer = self.signer.clone();
         let account_nonce = self.nonce.clone();
@@ -365,7 +375,7 @@ where
         );
 
         let extra = extrinsic::DefaultExtra::new(version, account_nonce, genesis_hash);
-        let xt = extrinsic::create_and_sign(signer, call, extra)?;
+        let xt = extrinsic::create_and_sign::<_, _, _, S, _>(signer, call, extra)?;
         Ok(xt)
     }
 
@@ -405,7 +415,7 @@ where
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::srml::{
+    use crate::paint::{
         balances::{
             Balances,
             BalancesStore,
@@ -420,7 +430,6 @@ mod tests {
     use substrate_keyring::AccountKeyring;
     use substrate_primitives::{
         storage::StorageKey,
-        Pair,
     };
 
     type Index = <Runtime as System>::Index;
@@ -444,7 +453,7 @@ mod tests {
         let signer = AccountKeyring::Alice.pair();
         let mut xt = rt.block_on(client.xt(signer, None)).unwrap();
 
-        let dest = AccountKeyring::Bob.pair().public();
+        let dest = AccountKeyring::Bob.to_account_id();
         let transfer = xt
             .balances(|calls| calls.transfer(dest.clone().into(), 10_000))
             .submit();
@@ -515,7 +524,7 @@ mod tests {
     fn test_state_read_free_balance() {
         let (mut rt, client) = test_setup();
 
-        let account = AccountKeyring::Alice.pair().public();
+        let account = AccountKeyring::Alice.to_account_id();
         rt.block_on(client.free_balance(account.into())).unwrap();
     }
 
@@ -547,11 +556,11 @@ mod tests {
         let (_, client) = test_setup();
 
         let balances = client.metadata().module("Balances").unwrap();
-        let dest = substrate_keyring::AccountKeyring::Bob.pair().public();
+        let dest = substrate_keyring::AccountKeyring::Bob.to_account_id();
         let address: Address = dest.clone().into();
         let amount: Balance = 10_000;
 
-        let transfer = srml_balances::Call::transfer(address.clone(), amount);
+        let transfer = paint_balances::Call::transfer(address.clone(), amount);
         let call = node_runtime::Call::Balances(transfer);
         let call2 = balances
             .call("transfer", (address, codec::compact(amount)))
@@ -559,7 +568,7 @@ mod tests {
         assert_eq!(call.encode().to_vec(), call2.0);
 
         let free_balance =
-            <srml_balances::FreeBalance<node_runtime::Runtime>>::hashed_key_for(&dest);
+            <paint_balances::FreeBalance<node_runtime::Runtime>>::hashed_key_for(&dest);
         let free_balance_key = StorageKey(free_balance);
         let free_balance_key2 = balances
             .storage("FreeBalance")
@@ -570,7 +579,7 @@ mod tests {
         assert_eq!(free_balance_key, free_balance_key2);
 
         let account_nonce =
-            <srml_system::AccountNonce<node_runtime::Runtime>>::hashed_key_for(&dest);
+            <paint_system::AccountNonce<node_runtime::Runtime>>::hashed_key_for(&dest);
         let account_nonce_key = StorageKey(account_nonce);
         let account_nonce_key2 = client
             .metadata()
diff --git a/src/srml/balances.rs b/src/paint/balances.rs
similarity index 83%
rename from src/srml/balances.rs
rename to src/paint/balances.rs
index affd02ce31..0bbc91dda8 100644
--- a/src/srml/balances.rs
+++ b/src/paint/balances.rs
@@ -1,4 +1,4 @@
-//! Implements support for the srml_balances module.
+//! Implements support for the paint_balances module.
 use crate::{
     codec::{
         compact,
@@ -6,7 +6,7 @@ use crate::{
     },
     error::Error,
     metadata::MetadataError,
-    srml::{
+    paint::{
         system::System,
         ModuleCalls,
     },
@@ -23,12 +23,14 @@ use runtime_primitives::traits::{
     MaybeSerialize,
     Member,
     SimpleArithmetic,
+    Verify,
+    IdentifyAccount,
 };
 use runtime_support::Parameter;
 use substrate_primitives::Pair;
 use std::fmt::Debug;
 
-/// The subset of the `srml_balances::Trait` that a client must implement.
+/// The subset of the `paint_balances::Trait` that a client must implement.
 pub trait Balances: System {
     /// The balance of an account.
     type Balance: Parameter
@@ -43,9 +45,9 @@ pub trait Balances: System {
 }
 
 /// Blanket impl for using existing runtime types
-impl<T: srml_system::Trait + srml_balances::Trait + Debug> Balances for T
+impl<T: paint_system::Trait + paint_balances::Trait + Debug> Balances for T
 where
-    <T as srml_system::Trait>::Header: serde::de::DeserializeOwned,
+    <T as paint_system::Trait>::Header: serde::de::DeserializeOwned,
 {
     type Balance = T::Balance;
 }
@@ -74,7 +76,7 @@ pub trait BalancesStore {
     ) -> Box<dyn Future<Item = <Self::Balances as Balances>::Balance, Error = Error> + Send>;
 }
 
-impl<T: Balances + 'static> BalancesStore for Client<T> {
+impl<T: Balances + 'static, S: 'static> BalancesStore for Client<T, S> {
     type Balances = T;
 
     fn free_balance(
@@ -105,23 +107,28 @@ pub trait BalancesXt {
     type Balances: Balances;
     /// Keypair type
     type Pair: Pair;
+    /// Signature type
+    type Signature: Verify;
 
-    /// Create a call for the srml balances module
-    fn balances<F>(&self, f: F) -> XtBuilder<Self::Balances, Self::Pair, Valid>
+    /// Create a call for the paint balances module
+    fn balances<F>(&self, f: F) -> XtBuilder<Self::Balances, Self::Pair, Self::Signature, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::Balances, Self::Pair>,
         ) -> Result<Encoded, MetadataError>;
 }
 
-impl<T: Balances + 'static, P, V> BalancesXt for XtBuilder<T, P, V>
+impl<T: Balances + 'static, P, S: 'static, V> BalancesXt for XtBuilder<T, P, S, V>
 where
     P: Pair,
+    S: Verify,
+    S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
 {
     type Balances = T;
     type Pair = P;
+    type Signature = S;
 
-    fn balances<F>(&self, f: F) -> XtBuilder<T, P, Valid>
+    fn balances<F>(&self, f: F) -> XtBuilder<T, P, S, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::Balances, Self::Pair>,
diff --git a/src/srml/contracts.rs b/src/paint/contracts.rs
similarity index 81%
rename from src/srml/contracts.rs
rename to src/paint/contracts.rs
index d6e8e41e0e..471fa3f3ec 100644
--- a/src/srml/contracts.rs
+++ b/src/paint/contracts.rs
@@ -1,11 +1,11 @@
-//! Implements support for the srml_contracts module.
+//! Implements support for the paint_contracts module.
 use crate::{
     codec::{
         compact,
         Encoded,
     },
     metadata::MetadataError,
-    srml::{
+    paint::{
         balances::Balances,
         system::System,
         ModuleCalls,
@@ -13,24 +13,28 @@ use crate::{
     Valid,
     XtBuilder,
 };
+use runtime_primitives::traits::{
+    IdentifyAccount,
+    Verify,
+};
 use substrate_primitives::Pair;
 
 /// Gas units are chosen to be represented by u64 so that gas metering
 /// instructions can operate on them efficiently.
 pub type Gas = u64;
 
-/// The subset of the `srml_contracts::Trait` that a client must implement.
+/// The subset of the `paint_contracts::Trait` that a client must implement.
 pub trait Contracts: System + Balances {}
 
 /// Blanket impl for using existing runtime types
 impl<
-        T: srml_contracts::Trait
-            + srml_system::Trait
-            + srml_balances::Trait
+        T: paint_contracts::Trait
+            + paint_system::Trait
+            + paint_balances::Trait
             + std::fmt::Debug,
     > Contracts for T
 where
-    <T as srml_system::Trait>::Header: serde::de::DeserializeOwned,
+    <T as paint_system::Trait>::Header: serde::de::DeserializeOwned,
 {
 }
 
@@ -40,23 +44,28 @@ pub trait ContractsXt {
     type Contracts: Contracts;
     /// Key Pair Type
     type Pair: Pair;
+    /// Signature type
+    type Signature: Verify;
 
-    /// Create a call for the srml contracts module
-    fn contracts<F>(&self, f: F) -> XtBuilder<Self::Contracts, Self::Pair, Valid>
+    /// Create a call for the paint contracts module
+    fn contracts<F>(&self, f: F) -> XtBuilder<Self::Contracts, Self::Pair, Self::Signature, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::Contracts, Self::Pair>,
         ) -> Result<Encoded, MetadataError>;
 }
 
-impl<T: Contracts + 'static, P, V> ContractsXt for XtBuilder<T, P, V>
+impl<T: Contracts + 'static, P, S: 'static, V> ContractsXt for XtBuilder<T, P, S, V>
 where
     P: Pair,
+    S: Verify,
+    S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
 {
     type Contracts = T;
     type Pair = P;
+    type Signature = S;
 
-    fn contracts<F>(&self, f: F) -> XtBuilder<T, P, Valid>
+    fn contracts<F>(&self, f: F) -> XtBuilder<T, P, S, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::Contracts, Self::Pair>,
diff --git a/src/srml/mod.rs b/src/paint/mod.rs
similarity index 100%
rename from src/srml/mod.rs
rename to src/paint/mod.rs
diff --git a/src/srml/system.rs b/src/paint/system.rs
similarity index 83%
rename from src/srml/system.rs
rename to src/paint/system.rs
index 3867df3b4e..d220bbc945 100644
--- a/src/srml/system.rs
+++ b/src/paint/system.rs
@@ -1,9 +1,9 @@
-//! Implements support for the srml_system module.
+//! Implements support for the paint_system module.
 use crate::{
     codec::Encoded,
     error::Error,
     metadata::MetadataError,
-    srml::{
+    paint::{
         balances::Balances,
         ModuleCalls,
     },
@@ -21,6 +21,7 @@ use runtime_primitives::traits::{
     CheckEqual,
     Hash,
     Header,
+    IdentifyAccount,
     MaybeDisplay,
     MaybeSerialize,
     MaybeSerializeDeserialize,
@@ -28,13 +29,14 @@ use runtime_primitives::traits::{
     SimpleArithmetic,
     SimpleBitOps,
     StaticLookup,
+    Verify,
 };
 use runtime_support::Parameter;
 use serde::de::DeserializeOwned;
 use substrate_primitives::Pair;
 use std::fmt::Debug;
 
-/// The subset of the `srml_system::Trait` that a client must implement.
+/// The subset of the `paint::Trait` that a client must implement.
 pub trait System: 'static + Eq + Clone + Debug {
     /// Account index (aka nonce) type. This stores the number of previous
     /// transactions associated with a sender account.
@@ -85,7 +87,7 @@ pub trait System: 'static + Eq + Clone + Debug {
         + Ord
         + Default;
 
-    /// The address type. This instead of `<srml_system::Trait::Lookup as StaticLookup>::Source`.
+    /// The address type. This instead of `<paint_system::Trait::Lookup as StaticLookup>::Source`.
     type Address: Codec + Clone + PartialEq + Debug;
 
     /// The block header.
@@ -95,9 +97,9 @@ pub trait System: 'static + Eq + Clone + Debug {
 }
 
 /// Blanket impl for using existing runtime types
-impl<T: srml_system::Trait + Debug> System for T
+impl<T: paint_system::Trait + Debug> System for T
 where
-    <T as srml_system::Trait>::Header: serde::de::DeserializeOwned,
+    <T as paint_system::Trait>::Header: serde::de::DeserializeOwned,
 {
     type Index = T::Index;
     type BlockNumber = T::BlockNumber;
@@ -120,7 +122,7 @@ pub trait SystemStore {
     ) -> Box<dyn Future<Item = <Self::System as System>::Index, Error = Error> + Send>;
 }
 
-impl<T: System + Balances + 'static> SystemStore for Client<T> {
+impl<T: System + Balances + 'static, S: 'static> SystemStore for Client<T, S> {
     type System = T;
 
     fn account_nonce(
@@ -149,23 +151,28 @@ pub trait SystemXt {
     type System: System;
     /// Keypair type
     type Pair: Pair;
+    /// Signature type
+    type Signature: Verify;
 
-    /// Create a call for the srml system module
-    fn system<F>(&self, f: F) -> XtBuilder<Self::System, Self::Pair, Valid>
+    /// Create a call for the paint system module
+    fn system<F>(&self, f: F) -> XtBuilder<Self::System, Self::Pair, Self::Signature, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::System, Self::Pair>,
         ) -> Result<Encoded, MetadataError>;
 }
 
-impl<T: System + Balances + 'static, P, V> SystemXt for XtBuilder<T, P, V>
+impl<T: System + Balances + 'static, P, S: 'static, V> SystemXt for XtBuilder<T, P, S, V>
 where
     P: Pair,
+    S: Verify,
+    S::Signer: From<P::Public> + IdentifyAccount<AccountId = T::AccountId>,
 {
     type System = T;
     type Pair = P;
+    type Signature = S;
 
-    fn system<F>(&self, f: F) -> XtBuilder<T, P, Valid>
+    fn system<F>(&self, f: F) -> XtBuilder<T, P, S, Valid>
     where
         F: FnOnce(
             ModuleCalls<Self::System, Self::Pair>,
diff --git a/src/rpc.rs b/src/rpc.rs
index 1cbd404713..205f5f6c92 100644
--- a/src/rpc.rs
+++ b/src/rpc.rs
@@ -21,7 +21,7 @@ use crate::{
         RuntimeEvent,
     },
     metadata::Metadata,
-    srml::{
+    paint::{
         balances::Balances,
         system::System,
     },
@@ -161,9 +161,9 @@ use txpool::watcher::Status;
 
 use crate::{
     events::RawEvent,
-    srml::system::SystemEvent,
+    paint::system::SystemEvent,
 };
-use srml_system::Phase;
+use paint_system::Phase;
 
 type MapClosure<T> = Box<dyn Fn(T) -> T + Send>;
 pub type MapStream<T> = stream::Map<TypedSubscriptionStream<T>, MapClosure<T>>;
diff --git a/src/runtimes.rs b/src/runtimes.rs
index 4d315618ed..a29238648a 100644
--- a/src/runtimes.rs
+++ b/src/runtimes.rs
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with substrate-subxt.  If not, see <http://www.gnu.org/licenses/>.
 
-use crate::srml::{
+use crate::paint::{
     balances::Balances,
     contracts::Contracts,
     system::System,
@@ -43,7 +43,7 @@ impl System for DefaultNodeRuntime {
     type Hash = substrate_primitives::H256;
     type Hashing = BlakeTwo256;
     type AccountId = <AnySignature as Verify>::Signer;
-    type Address = srml_indices::address::Address<Self::AccountId, u32>;
+    type Address = paint_indices::address::Address<Self::AccountId, u32>;
     type Header = Header<Self::BlockNumber, BlakeTwo256>;
 }