Use tokio instead of async-std (#495)

* examples: Use tokio instead of std async

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

* test-runtime: Use tokio instead of std async

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

* subxt: Use tokio instead of std async

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

* examples: Use only necessary tokio features

Signed-off-by: Alexandru Vasile <alexandru.vasile@parity.io>

examples/examples/balance_transfer.rs

@@ -33,7 +33,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/balance_transfer_with_params.rs

@@ -38,7 +38,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/custom_config.rs

@@ -55,7 +55,7 @@ impl Config for MyConfig {
     type Extrinsic = <DefaultConfig as Config>::Extrinsic;
 }
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let api = ClientBuilder::new()
         .build()

examples/examples/custom_type_derives.rs

@@ -30,7 +30,7 @@ pub mod polkadot {}
 
 use polkadot::runtime_types::frame_support::PalletId;
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let pallet_id = PalletId([1u8; 8]);
     let _ = pallet_id.clone();

examples/examples/fetch_all_accounts.rs

@@ -31,7 +31,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/fetch_staking_details.rs

@@ -37,7 +37,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/rpc_call.rs

@@ -31,7 +31,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/submit_and_watch.rs

@@ -34,7 +34,7 @@ use subxt::{
 #[subxt::subxt(runtime_metadata_path = "examples/polkadot_metadata.scale")]
 pub mod polkadot {}
 
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 

examples/examples/subscribe_all_events.rs

@@ -37,7 +37,7 @@ pub mod polkadot {}
 
 /// Subscribe to all events, and then manually look through them and
 /// pluck out the events that we care about.
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 
@@ -50,7 +50,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut event_sub = api.events().subscribe().await?;
 
     // While this subscription is active, balance transfers are made somewhere:
-    async_std::task::spawn(async {
+    tokio::task::spawn(async {
         let signer = PairSigner::new(AccountKeyring::Alice.pair());
         let api =
             ClientBuilder::new()
@@ -73,7 +73,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
                 .await
                 .unwrap();
 
-            async_std::task::sleep(Duration::from_secs(10)).await;
+            tokio::time::sleep(Duration::from_secs(10)).await;
             transfer_amount += 100_000_000;
         }
     });

examples/examples/subscribe_one_event.rs

@@ -37,7 +37,7 @@ pub mod polkadot {}
 
 /// Subscribe to all events, and then manually look through them and
 /// pluck out the events that we care about.
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 
@@ -56,7 +56,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         .filter_events::<(polkadot::balances::events::Transfer,)>();
 
     // While this subscription is active, we imagine some balance transfers are made somewhere else:
-    async_std::task::spawn(async {
+    tokio::task::spawn(async {
         let signer = PairSigner::new(AccountKeyring::Alice.pair());
         let api =
             ClientBuilder::new()
@@ -76,7 +76,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
                 .sign_and_submit_default(&signer)
                 .await
                 .unwrap();
-            async_std::task::sleep(Duration::from_secs(10)).await;
+            tokio::time::sleep(Duration::from_secs(10)).await;
         }
     });
 

examples/examples/subscribe_some_events.rs

@@ -37,7 +37,7 @@ pub mod polkadot {}
 
 /// Subscribe to all events, and then manually look through them and
 /// pluck out the events that we care about.
-#[async_std::main]
+#[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     env_logger::init();
 
@@ -57,7 +57,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     )>();
 
     // While this subscription is active, we imagine some balance transfers are made somewhere else:
-    async_std::task::spawn(async {
+    tokio::task::spawn(async {
         let signer = PairSigner::new(AccountKeyring::Alice.pair());
         let api =
             ClientBuilder::new()
@@ -77,7 +77,7 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
                 .sign_and_submit_default(&signer)
                 .await
                 .unwrap();
-            async_std::task::sleep(Duration::from_secs(10)).await;
+            tokio::time::sleep(Duration::from_secs(10)).await;
         }
     });