More simplifications around view context objects (#2438)

* move MemoryContext to context.rs, remove all other context aliases

* Rename ContextFromStore into ViewContext

* SDK: hide the notion of KV store during initialization

* rename ViewContext::create into ViewContext::create_root_context

* fix graphql schema again

* reviewer suggestions

examples/amm/src/contract.rs

@@ -9,7 +9,7 @@ use amm::{AmmAbi, Message, Operation, Parameters};
 use fungible::{Account, FungibleTokenAbi};
 use linera_sdk::{
     base::{AccountOwner, Amount, ApplicationId, ChainId, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 use num_bigint::BigUint;
@@ -34,7 +34,7 @@ impl Contract for AmmContract {
     type Parameters = Parameters;
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = Amm::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = Amm::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         AmmContract { state, runtime }

examples/amm/src/service.rs

@@ -10,10 +10,7 @@ use std::sync::Arc;
 use amm::{Operation, Parameters};
 use async_graphql::{EmptySubscription, Request, Response, Schema};
 use linera_sdk::{
-    base::WithServiceAbi,
-    graphql::GraphQLMutationRoot,
-    views::{View, ViewStorageContext},
-    Service, ServiceRuntime,
+    base::WithServiceAbi, graphql::GraphQLMutationRoot, views::View, Service, ServiceRuntime,
 };
 
 use self::state::Amm;
@@ -32,7 +29,7 @@ impl Service for AmmService {
     type Parameters = Parameters;
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = Amm::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = Amm::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         AmmService {

examples/counter/src/contract.rs

@@ -8,7 +8,7 @@ mod state;
 use counter::CounterAbi;
 use linera_sdk::{
     base::WithContractAbi,
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 
@@ -31,7 +31,7 @@ impl Contract for CounterContract {
     type Parameters = ();
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = Counter::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = Counter::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         CounterContract { state, runtime }
@@ -62,11 +62,7 @@ impl Contract for CounterContract {
 #[cfg(test)]
 mod tests {
     use futures::FutureExt as _;
-    use linera_sdk::{
-        util::BlockingWait,
-        views::{View, ViewStorageContext},
-        Contract, ContractRuntime,
-    };
+    use linera_sdk::{util::BlockingWait, views::View, Contract, ContractRuntime};
 
     use super::{Counter, CounterContract};
 
@@ -121,7 +117,7 @@ mod tests {
     fn create_and_instantiate_counter(initial_value: u64) -> CounterContract {
         let runtime = ContractRuntime::new().with_application_parameters(());
         let mut contract = CounterContract {
-            state: Counter::load(ViewStorageContext::from(runtime.key_value_store()))
+            state: Counter::load(runtime.root_view_storage_context())
                 .blocking_wait()
                 .expect("Failed to read from mock key value store"),
             runtime,

examples/counter/src/service.rs

@@ -6,11 +6,7 @@
 mod state;
 
 use async_graphql::{EmptySubscription, Object, Request, Response, Schema};
-use linera_sdk::{
-    base::WithServiceAbi,
-    views::{View, ViewStorageContext},
-    Service, ServiceRuntime,
-};
+use linera_sdk::{base::WithServiceAbi, views::View, Service, ServiceRuntime};
 
 use self::state::Counter;
 
@@ -28,7 +24,7 @@ impl Service for CounterService {
     type Parameters = ();
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = Counter::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = Counter::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         CounterService { state }
@@ -71,11 +67,7 @@ impl QueryRoot {
 mod tests {
     use async_graphql::{Request, Response, Value};
     use futures::FutureExt as _;
-    use linera_sdk::{
-        util::BlockingWait,
-        views::{View, ViewStorageContext},
-        Service, ServiceRuntime,
-    };
+    use linera_sdk::{util::BlockingWait, views::View, Service, ServiceRuntime};
     use serde_json::json;
 
     use super::{Counter, CounterService};
@@ -84,7 +76,7 @@ mod tests {
     fn query() {
         let value = 61_098_721_u64;
         let runtime = ServiceRuntime::<CounterService>::new();
-        let mut state = Counter::load(ViewStorageContext::from(runtime.key_value_store()))
+        let mut state = Counter::load(runtime.root_view_storage_context())
             .blocking_wait()
             .expect("Failed to read from mock key value store");
         state.value.set(value);

examples/crowd-funding/src/contract.rs

@@ -9,7 +9,7 @@ use crowd_funding::{CrowdFundingAbi, InstantiationArgument, Message, Operation};
 use fungible::{Account, FungibleTokenAbi};
 use linera_sdk::{
     base::{AccountOwner, Amount, ApplicationId, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 use state::{CrowdFunding, Status};
@@ -31,7 +31,7 @@ impl Contract for CrowdFundingContract {
     type Parameters = ApplicationId<fungible::FungibleTokenAbi>;
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = CrowdFunding::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = CrowdFunding::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         CrowdFundingContract { state, runtime }

examples/crowd-funding/src/service.rs

@@ -12,7 +12,7 @@ use crowd_funding::Operation;
 use linera_sdk::{
     base::{ApplicationId, WithServiceAbi},
     graphql::GraphQLMutationRoot,
-    views::{View, ViewStorageContext},
+    views::View,
     Service, ServiceRuntime,
 };
 use state::CrowdFunding;
@@ -31,7 +31,7 @@ impl Service for CrowdFundingService {
     type Parameters = ApplicationId<fungible::FungibleTokenAbi>;
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = CrowdFunding::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = CrowdFunding::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         CrowdFundingService {

examples/ethereum-tracker/src/contract.rs

@@ -9,7 +9,7 @@ use ethereum_tracker::{EthereumTrackerAbi, InstantiationArgument, U256Cont};
 use linera_sdk::{
     base::WithContractAbi,
     ethereum::{EthereumClient, EthereumDataType, EthereumQueries as _},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 
@@ -32,7 +32,7 @@ impl Contract for EthereumTrackerContract {
     type Parameters = ();
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = EthereumTracker::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = EthereumTracker::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         EthereumTrackerContract { state, runtime }

examples/ethereum-tracker/src/service.rs

@@ -10,10 +10,7 @@ use std::sync::Arc;
 use async_graphql::{EmptySubscription, Request, Response, Schema};
 use ethereum_tracker::Operation;
 use linera_sdk::{
-    base::WithServiceAbi,
-    graphql::GraphQLMutationRoot,
-    views::{View, ViewStorageContext},
-    Service, ServiceRuntime,
+    base::WithServiceAbi, graphql::GraphQLMutationRoot, views::View, Service, ServiceRuntime,
 };
 
 use self::state::EthereumTracker;
@@ -33,7 +30,7 @@ impl Service for EthereumTrackerService {
     type Parameters = ();
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = EthereumTracker::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = EthereumTracker::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         EthereumTrackerService {

examples/fungible/src/contract.rs

@@ -12,7 +12,7 @@ use fungible::{
 };
 use linera_sdk::{
     base::{AccountOwner, Amount, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 
@@ -35,7 +35,7 @@ impl Contract for FungibleTokenContract {
     type InstantiationArgument = InitialState;
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = FungibleToken::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = FungibleToken::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         FungibleTokenContract { state, runtime }

examples/fungible/src/service.rs

@@ -12,7 +12,7 @@ use fungible::{Operation, Parameters};
 use linera_sdk::{
     base::{AccountOwner, Amount, WithServiceAbi},
     graphql::GraphQLMutationRoot,
-    views::{MapView, View, ViewStorageContext},
+    views::{MapView, View},
     Service, ServiceRuntime,
 };
 
@@ -34,7 +34,7 @@ impl Service for FungibleTokenService {
     type Parameters = Parameters;
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = FungibleToken::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = FungibleToken::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         FungibleTokenService {

examples/gen-nft/src/contract.rs

@@ -11,7 +11,7 @@ use fungible::Account;
 use gen_nft::{GenNftAbi, Message, Nft, Operation, TokenId};
 use linera_sdk::{
     base::{AccountOwner, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 
@@ -34,7 +34,7 @@ impl Contract for GenNftContract {
     type Parameters = ();
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = GenNft::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = GenNft::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         GenNftContract { state, runtime }

examples/gen-nft/src/service.rs

@@ -19,7 +19,7 @@ use fungible::Account;
 use gen_nft::{NftOutput, Operation, TokenId};
 use linera_sdk::{
     base::{AccountOwner, WithServiceAbi},
-    views::{View, ViewStorageContext},
+    views::View,
     Service, ServiceRuntime,
 };
 use log::info;
@@ -42,7 +42,7 @@ impl Service for GenNftService {
     type Parameters = ();
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = GenNft::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = GenNft::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         GenNftService {

examples/hex-game/src/contract.rs

@@ -12,7 +12,7 @@ use linera_sdk::{
         Amount, ApplicationPermissions, ChainId, ChainOwnership, Owner, PublicKey, TimeoutConfig,
         WithContractAbi,
     },
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 use serde::{Deserialize, Serialize};
@@ -35,7 +35,7 @@ impl Contract for HexContract {
     type Parameters = ();
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = HexState::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = HexState::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         HexContract { state, runtime }

examples/hex-game/src/service.rs

@@ -10,10 +10,7 @@ use std::sync::{Arc, Mutex};
 use async_graphql::{ComplexObject, Context, EmptySubscription, Request, Response, Schema};
 use hex_game::{Operation, Player};
 use linera_sdk::{
-    base::WithServiceAbi,
-    graphql::GraphQLMutationRoot,
-    views::{View, ViewStorageContext},
-    Service, ServiceRuntime,
+    base::WithServiceAbi, graphql::GraphQLMutationRoot, views::View, Service, ServiceRuntime,
 };
 
 use self::state::HexState;
@@ -34,7 +31,7 @@ impl Service for HexService {
     type Parameters = ();
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = HexState::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = HexState::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         HexService {
@@ -76,19 +73,15 @@ impl HexState {
 #[cfg(test)]
 mod tests {
     use async_graphql::{futures_util::FutureExt, Request};
-    use linera_sdk::{
-        util::BlockingWait,
-        views::{View, ViewStorageContext},
-        Service, ServiceRuntime,
-    };
+    use linera_sdk::{util::BlockingWait, views::View, Service, ServiceRuntime};
     use serde_json::json;
 
     use super::*;
 
     #[test]
     fn query() {
         let runtime = ServiceRuntime::<HexService>::new();
-        let state = HexState::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = HexState::load(runtime.root_view_storage_context())
             .blocking_wait()
             .expect("Failed to read from mock key value store");
 

examples/matching-engine/src/contract.rs

@@ -9,7 +9,7 @@ use std::cmp::min;
 use fungible::{Account, FungibleTokenAbi};
 use linera_sdk::{
     base::{AccountOwner, Amount, ApplicationId, ChainId, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime,
 };
 use matching_engine::{
@@ -57,7 +57,7 @@ impl Contract for MatchingEngineContract {
     type Parameters = Parameters;
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = MatchingEngine::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = MatchingEngine::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         MatchingEngineContract { state, runtime }

examples/matching-engine/src/service.rs

@@ -9,10 +9,7 @@ use std::sync::Arc;
 
 use async_graphql::{EmptySubscription, Request, Response, Schema};
 use linera_sdk::{
-    base::WithServiceAbi,
-    graphql::GraphQLMutationRoot,
-    views::{View, ViewStorageContext},
-    Service, ServiceRuntime,
+    base::WithServiceAbi, graphql::GraphQLMutationRoot, views::View, Service, ServiceRuntime,
 };
 use matching_engine::{Operation, Parameters};
 
@@ -32,7 +29,7 @@ impl Service for MatchingEngineService {
     type Parameters = Parameters;
 
     async fn new(runtime: ServiceRuntime<Self>) -> Self {
-        let state = MatchingEngine::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = MatchingEngine::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         MatchingEngineService {

examples/non-fungible/src/contract.rs

@@ -10,7 +10,7 @@ use std::collections::BTreeSet;
 use fungible::Account;
 use linera_sdk::{
     base::{AccountOwner, WithContractAbi},
-    views::{RootView, View, ViewStorageContext},
+    views::{RootView, View},
     Contract, ContractRuntime, DataBlobHash,
 };
 use non_fungible::{Message, Nft, NonFungibleTokenAbi, Operation, TokenId};
@@ -34,7 +34,7 @@ impl Contract for NonFungibleTokenContract {
     type Parameters = ();
 
     async fn load(runtime: ContractRuntime<Self>) -> Self {
-        let state = NonFungibleToken::load(ViewStorageContext::from(runtime.key_value_store()))
+        let state = NonFungibleToken::load(runtime.root_view_storage_context())
             .await
             .expect("Failed to load state");
         NonFungibleTokenContract { state, runtime }