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Gav Demo Runtime from Web3 Summit
// initialise with:
// post({sender: runtime.indices.ss58Decode('F7Gh'), call: calls.demo.setPayment(1000)}).tie(console.log)
use parity_codec::Encode;
use srml_support::{StorageValue, dispatch::Result, decl_module, decl_storage};
use runtime_primitives::traits::Hash;
use {balances, system::{self, ensure_signed}};
pub trait Trait: balances::Trait {}
decl_module! {
pub struct Module<T: Trait> for enum Call where origin: T::Origin {
fn play(origin) -> Result {
let sender = ensure_signed(origin)?;
let payment = Self::payment().ok_or("Must have payment amount set")?;
<balances::Module<T>>::decrease_free_balance(&sender, payment)?;
if (<system::Module<T>>::random_seed(), &sender)
.using_encoded(<T as system::Trait>::Hashing::hash)
.using_encoded(|e| e[0] < 128)
<balances::Module<T>>::increase_free_balance_creating(&sender, <Pot<T>>::take());
<Pot<T>>::mutate(|pot| *pot += payment);
fn set_payment(_origin, value: T::Balance) -> Result {
if Self::payment().is_none() {
decl_storage! {
trait Store for Module<T: Trait> as Demo {
Payment get(payment): Option<T::Balance>;
Pot get(pot): T::Balance;
//! The Substrate Node Template runtime. This can be compiled with `#[no_std]`, ready for Wasm.
#![cfg_attr(not(feature = "std"), no_std)]
#![cfg_attr(not(feature = "std"), feature(alloc))]
// `construct_runtime!` does a lot of recursion and requires us to increase the limit to 256.
#[cfg(feature = "std")]
extern crate serde_derive;
use substrate_client as client;
extern crate parity_codec_derive;
use rstd::prelude::*;
#[cfg(feature = "std")]
use primitives::bytes;
use primitives::{Ed25519AuthorityId, OpaqueMetadata};
use runtime_primitives::{
ApplyResult, transaction_validity::TransactionValidity, Ed25519Signature, generic,
traits::{self, BlakeTwo256, Block as BlockT, StaticLookup}, create_runtime_str
use client::{
block_builder::api::{CheckInherentsResult, InherentData, self as block_builder_api},
runtime_api, impl_runtime_apis
use version::RuntimeVersion;
#[cfg(feature = "std")]
use version::NativeVersion;
// A few exports that help ease life for downstream crates.
#[cfg(any(feature = "std", test))]
pub use runtime_primitives::BuildStorage;
pub use consensus::Call as ConsensusCall;
pub use timestamp::Call as TimestampCall;
pub use balances::Call as BalancesCall;
pub use runtime_primitives::{Permill, Perbill};
pub use timestamp::BlockPeriod;
pub use srml_support::{StorageValue, construct_runtime};
/// Alias to Ed25519 pubkey that identifies an account on the chain.
pub type AccountId = primitives::H256;
/// A hash of some data used by the chain.
pub type Hash = primitives::H256;
/// Index of a block number in the chain.
pub type BlockNumber = u64;
/// Index of an account's extrinsic in the chain.
pub type Nonce = u64;
mod demo;
/// Opaque types. These are used by the CLI to instantiate machinery that don't need to know
/// the specifics of the runtime. They can then be made to be agnostic over specific formats
/// of data like extrinsics, allowing for them to continue syncing the network through upgrades
/// to even the core datastructures.
pub mod opaque {
use super::*;
/// Opaque, encoded, unchecked extrinsic.
#[derive(PartialEq, Eq, Clone, Default, Encode, Decode)]
#[cfg_attr(feature = "std", derive(Serialize, Deserialize, Debug))]
pub struct UncheckedExtrinsic(#[cfg_attr(feature = "std", serde(with="bytes"))] pub Vec<u8>);
impl traits::Extrinsic for UncheckedExtrinsic {
fn is_signed(&self) -> Option<bool> {
/// Opaque block header type.
pub type Header = generic::Header<BlockNumber, BlakeTwo256, generic::DigestItem<Hash, Ed25519AuthorityId>>;
/// Opaque block type.
pub type Block = generic::Block<Header, UncheckedExtrinsic>;
/// Opaque block identifier type.
pub type BlockId = generic::BlockId<Block>;
/// Opaque session key type.
pub type SessionKey = Ed25519AuthorityId;
/// This runtime version.
pub const VERSION: RuntimeVersion = RuntimeVersion {
spec_name: create_runtime_str!("substrate-node-template"),
impl_name: create_runtime_str!("substrate-node-template"),
authoring_version: 3,
spec_version: 3,
impl_version: 0,
/// The version infromation used to identify this runtime when compiled natively.
#[cfg(feature = "std")]
pub fn native_version() -> NativeVersion {
NativeVersion {
runtime_version: VERSION,
can_author_with: Default::default(),
impl system::Trait for Runtime {
/// The identifier used to distinguish between accounts.
type AccountId = AccountId;
/// The lookup mechanism to get account ID from whatever is passed in dispatchers.
type Lookup = Indices;
/// The index type for storing how many extrinsics an account has signed.
type Index = Nonce;
/// The index type for blocks.
type BlockNumber = BlockNumber;
/// The type for hashing blocks and tries.
type Hash = Hash;
/// The hashing algorithm used.
type Hashing = BlakeTwo256;
/// The header digest type.
type Digest = generic::Digest<Log>;
/// The header type.
type Header = generic::Header<BlockNumber, BlakeTwo256, Log>;
/// The ubiquitous event type.
type Event = Event;
/// The ubiquitous log type.
type Log = Log;
/// The ubiquitous origin type.
type Origin = Origin;
impl aura::Trait for Runtime {
type HandleReport = ();
impl consensus::Trait for Runtime {
/// The identifier we use to refer to authorities.
type SessionKey = Ed25519AuthorityId;
// The aura module handles offline-reports internally
// rather than using an explicit report system.
type InherentOfflineReport = ();
/// The ubiquitous log type.
type Log = Log;
impl indices::Trait for Runtime {
/// The type for recording indexing into the account enumeration. If this ever overflows, there
/// will be problems!
type AccountIndex = u32;
/// Use the standard means of resolving an index hint from an id.
type ResolveHint = indices::SimpleResolveHint<Self::AccountId, Self::AccountIndex>;
/// Determine whether an account is dead.
type IsDeadAccount = Balances;
/// The uniquitous event type.
type Event = Event;
impl timestamp::Trait for Runtime {
/// A timestamp: seconds since the unix epoch.
type Moment = u64;
type OnTimestampSet = Aura;
impl balances::Trait for Runtime {
/// The type for recording an account's balance.
type Balance = u128;
/// What to do if an account's free balance gets zeroed.
type OnFreeBalanceZero = ();
/// What to do if a new account is created.
type OnNewAccount = Indices;
/// Restrict whether an account can transfer funds. We don't place any further restrictions.
type EnsureAccountLiquid = ();
/// The uniquitous event type.
type Event = Event;
impl sudo::Trait for Runtime {
/// The uniquitous event type.
type Event = Event;
type Proposal = Call;
impl demo::Trait for Runtime {}
pub enum Runtime with Log(InternalLog: DigestItem<Hash, Ed25519AuthorityId>) where
Block = Block,
NodeBlock = opaque::Block,
UncheckedExtrinsic = UncheckedExtrinsic
System: system::{default, Log(ChangesTrieRoot)},
Timestamp: timestamp::{Module, Call, Storage, Config<T>, Inherent},
Consensus: consensus::{Module, Call, Storage, Config<T>, Log(AuthoritiesChange), Inherent},
Aura: aura::{Module},
Indices: indices,
Balances: balances,
Sudo: sudo,
Demo: demo::{Module, Call, Storage},
/// The type used as a helper for interpreting the sender of transactions.
type Context = system::ChainContext<Runtime>;
/// The address format for describing accounts.
type Address = <Indices as StaticLookup>::Source;
/// Block header type as expected by this runtime.
pub type Header = generic::Header<BlockNumber, BlakeTwo256, Log>;
/// Block type as expected by this runtime.
pub type Block = generic::Block<Header, UncheckedExtrinsic>;
/// BlockId type as expected by this runtime.
pub type BlockId = generic::BlockId<Block>;
/// Unchecked extrinsic type as expected by this runtime.
pub type UncheckedExtrinsic = generic::UncheckedMortalCompactExtrinsic<Address, Nonce, Call, Ed25519Signature>;
/// Extrinsic type that has already been checked.
pub type CheckedExtrinsic = generic::CheckedExtrinsic<AccountId, Nonce, Call>;
/// Executive: handles dispatch to the various modules.
pub type Executive = executive::Executive<Runtime, Block, Context, Balances, AllModules>;
// Implement our runtime API endpoints. This is just a bunch of proxying.
impl_runtime_apis! {
impl runtime_api::Core<Block> for Runtime {
fn version() -> RuntimeVersion {
fn authorities() -> Vec<Ed25519AuthorityId> {
fn execute_block(block: Block) {
fn initialise_block(header: &<Block as BlockT>::Header) {
impl runtime_api::Metadata<Block> for Runtime {
fn metadata() -> OpaqueMetadata {
impl block_builder_api::BlockBuilder<Block> for Runtime {
fn apply_extrinsic(extrinsic: <Block as BlockT>::Extrinsic) -> ApplyResult {
fn finalise_block() -> <Block as BlockT>::Header {
fn inherent_extrinsics(data: InherentData) -> Vec<<Block as BlockT>::Extrinsic> {
fn check_inherents(block: Block, data: InherentData) -> CheckInherentsResult {
fn random_seed() -> <Block as BlockT>::Hash {
impl runtime_api::TaggedTransactionQueue<Block> for Runtime {
fn validate_transaction(tx: <Block as BlockT>::Extrinsic) -> TransactionValidity {
impl consensus_aura::AuraApi<Block> for Runtime {
fn slot_duration() -> u64 {
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