FEATURE: Callback scheduling

.gitignore

@@ -18,6 +18,8 @@ coverage.lcov
 lcov.info
 *.pkey
 
+imports*
+
 # Private flow.jsons
 
 private.flow.json

contracts/testContracts/TestFlowCallbackHandler.cdc

@@ -0,0 +1,77 @@
+import "FlowCallbackScheduler"
+import "FlowToken"
+import "FungibleToken"
+
+// TestFlowCallbackHandler is a simplified test contract for testing CallbackScheduler
+access(all) contract TestFlowCallbackHandler {
+    access(all) var scheduledCallbacks: {UInt64: FlowCallbackScheduler.ScheduledCallback}
+    access(all) var succeededCallbacks: [UInt64]
+
+    access(all) let HandlerStoragePath: StoragePath
+    access(all) let HandlerPublicPath: PublicPath
+
+    access(all) resource Handler: FlowCallbackScheduler.CallbackHandler {
+
+        access(FlowCallbackScheduler.Execute) 
+        fun executeCallback(id: UInt64, data: AnyStruct?) {
+            // Most callbacks will have string data
+            if let dataString = data as? String {
+                // intentional failure test case
+                if dataString == "fail" {
+                    panic("Callback \(id) failed")
+                } else {
+                    // All other regular test cases should succeed
+                    TestFlowCallbackHandler.succeededCallbacks.append(id)
+                }
+            } else if let dataCap = data as? Capability<auth(FlowCallbackScheduler.Execute) &{FlowCallbackScheduler.CallbackHandler}> {
+                // Testing scheduling a callback with a callback
+                let scheduledCallback = FlowCallbackScheduler.schedule(
+                    callback: dataCap,
+                    data: "test data",
+                    timestamp: getCurrentBlock().timestamp + 10.0,
+                    priority: FlowCallbackScheduler.Priority.High,
+                    executionEffort: UInt64(1000),
+                    fees: <-TestFlowCallbackHandler.getFeeFromVault(amount: 1.0)
+                )
+                TestFlowCallbackHandler.addScheduledCallback(callback: scheduledCallback)
+            } else {
+                panic("TestFlowCallbackHandler.executeCallback: Invalid data type for callback with id \(id). Type is \(data.getType().identifier)")
+            }
+        }
+    }
+
+    access(all) fun createHandler(): @Handler {
+        return <- create Handler()
+    }
+
+    access(all) fun addScheduledCallback(callback: FlowCallbackScheduler.ScheduledCallback) {
+        self.scheduledCallbacks[callback.id] = callback
+    }
+
+    access(all) fun cancelCallback(id: UInt64): @FlowToken.Vault {
+        let callback = self.scheduledCallbacks[id]
+            ?? panic("Invalid ID: \(id) callback not found")
+        self.scheduledCallbacks[id] = nil
+        return <-FlowCallbackScheduler.cancel(callback: callback)
+    }
+
+    access(all) fun getSucceededCallbacks(): [UInt64] {
+        return self.succeededCallbacks
+    }
+
+    access(contract) fun getFeeFromVault(amount: UFix64): @FlowToken.Vault {
+        // borrow a reference to the vault that will be used for fees
+        let vault = self.account.storage.borrow<auth(FungibleToken.Withdraw) &FlowToken.Vault>(from: /storage/flowTokenVault)
+            ?? panic("Could not borrow FlowToken vault")
+
+        return <- vault.withdraw(amount: amount) as! @FlowToken.Vault
+    }
+
+    access(all) init() {
+        self.scheduledCallbacks = {}
+        self.succeededCallbacks = []
+
+        self.HandlerStoragePath = /storage/testCallbackHandler
+        self.HandlerPublicPath = /public/testCallbackHandler
+    }
+} 

flow.json

@@ -17,6 +17,13 @@
 				"testnet": "8c5303eaa26202d6"
 			}
 		},
+		"FlowCallbackScheduler": {
+			"source": "./contracts/FlowCallbackScheduler.cdc",
+			"aliases": {
+				"emulator": "f8d6e0586b0a20c7",
+				"testing": "0000000000000001"
+			}
+		},
 		"FlowClusterQC": {
 			"source": "./contracts/epochs/FlowClusterQC.cdc",
 			"aliases": {
@@ -44,12 +51,21 @@
 				"testnet": "9eca2b38b18b5dfe"
 			}
 		},
+		"FlowExecutionParameters": {
+			"source": "./contracts/FlowExecutionParameters.cdc",
+			"aliases": {
+				"emulator": "f8d6e0586b0a20c7",
+				"mainnet": "f426ff57ee8f6110",
+				"testing": "0000000000000007",
+				"testnet": "6997a2f2cf57b73a"
+			}
+		},
 		"FlowFees": {
 			"source": "./contracts/FlowFees.cdc",
 			"aliases": {
 				"emulator": "e5a8b7f23e8b548f",
 				"mainnet": "f919ee77447b7497",
-				"testing": "0000000000000007",
+				"testing": "0000000000000004",
 				"testnet": "912d5440f7e3769e"
 			}
 		},
@@ -62,15 +78,6 @@
 				"testnet": "9eca2b38b18b5dfe"
 			}
 		},
-        "FlowExecutionParameters": {
-			"source": "./contracts/FlowExecutionParameters.cdc",
-			"aliases": {
-				"emulator": "f8d6e0586b0a20c7",
-				"mainnet": "f426ff57ee8f6110",
-				"testing": "0000000000000007",
-				"testnet": "6997a2f2cf57b73a"
-			}
-		},
 		"FlowServiceAccount": {
 			"source": "./contracts/FlowServiceAccount.cdc",
 			"aliases": {
@@ -94,7 +101,7 @@
 			"aliases": {
 				"emulator": "f8d6e0586b0a20c7",
 				"mainnet": "e467b9dd11fa00df",
-				"testing": "0000000000000007",
+				"testing": "0000000000000001",
 				"testnet": "8c5303eaa26202d6"
 			}
 		},
@@ -103,7 +110,7 @@
 			"aliases": {
 				"emulator": "0ae53cb6e3f42a79",
 				"mainnet": "1654653399040a61",
-				"testing": "0000000000000007",
+				"testing": "0000000000000003",
 				"testnet": "7e60df042a9c0868"
 			}
 		},
@@ -112,14 +119,14 @@
 			"aliases": {
 				"emulator": "ee82856bf20e2aa6",
 				"mainnet": "f233dcee88fe0abe",
-				"testing": "0000000000000007",
+				"testing": "0000000000000002",
 				"testnet": "9a0766d93b6608b7"
 			}
 		},
 		"LinearCodeAddressGenerator": {
 			"source": "./contracts/LinearCodeAddressGenerator.cdc",
 			"aliases": {
-				"testing": "0x0000000000000007"
+				"testing": "0000000000000007"
 			}
 		},
 		"LockedTokens": {
@@ -157,6 +164,13 @@
 				"testing": "0000000000000007",
 				"testnet": "7aad92e5a0715d21"
 			}
+		},
+		"TestFlowCallbackHandler": {
+			"source": "./contracts/testContracts/TestFlowCallbackHandler.cdc",
+			"aliases": {
+				"emulator": "f8d6e0586b0a20c7",
+				"testing": "0000000000000001"
+			}
 		}
 	},
 	"networks": {
@@ -168,7 +182,14 @@
 	"accounts": {
 		"emulator-account": {
 			"address": "f8d6e0586b0a20c7",
-			"key": "7677f7c9410f8773b482737c778b5d7c6acfdbbae718d61e4727a07667f66004"
+			"key": "aff3a277caf2bdd6582c156ae7b07dbca537da7833309de88e56987faa2c0f1b"
+		}
+	},
+	"deployments": {
+		"emulator": {
+			"emulator-account": [
+				"TestFlowCallbackHandler"
+			]
 		}
 	}
 }

lib/go/contracts/contracts.go

@@ -44,28 +44,31 @@ const (
 	flowRandomBeaconHistoryFilename    = "RandomBeaconHistory.cdc"
 	cryptoFilename                     = "Crypto.cdc"
 	linearCodeAddressGeneratorFilename = "LinearCodeAddressGenerator.cdc"
+	flowCallbackSchedulerFilename      = "FlowCallbackScheduler.cdc"
 
 	// Test contracts
 	// only used for testing
-	TESTFlowIdentityTableFilename = "testContracts/TestFlowIDTableStaking.cdc"
+	TESTFlowIdentityTableFilename   = "testContracts/TestFlowIDTableStaking.cdc"
+	TESTflowCallbackHandlerFilename = "testContracts/TestFlowCallbackHandler.cdc"
 
 	// Each contract has placeholder addresses that need to be replaced
 	// depending on which network they are being used with
-	placeholderFungibleTokenAddress     = "\"FungibleToken\""
-	placeholderFungibleTokenMVAddress   = "\"FungibleTokenMetadataViews\""
-	placeholderMetadataViewsAddress     = "\"MetadataViews\""
-	placeholderFlowTokenAddress         = "\"FlowToken\""
-	placeholderIDTableAddress           = "\"FlowIDTableStaking\""
-	placeholderBurnerAddress            = "\"Burner\""
-	placeholderStakingProxyAddress      = "\"StakingProxy\""
-	placeholderQCAddr                   = "\"FlowClusterQC\""
-	placeholderDKGAddr                  = "\"FlowDKG\""
-	placeholderEpochAddr                = "\"FlowEpoch\""
-	placeholderFlowFeesAddress          = "\"FlowFees\""
-	placeholderStorageFeesAddress       = "\"FlowStorageFees\""
-	placeholderLockedTokensAddress      = "\"LockedTokens\""
-	placeholderStakingCollectionAddress = "\"FlowStakingCollection\""
-	placeholderNodeVersionBeaconAddress = "\"NodeVersionBeacon\""
+	placeholderFungibleTokenAddress         = "\"FungibleToken\""
+	placeholderFungibleTokenMVAddress       = "\"FungibleTokenMetadataViews\""
+	placeholderMetadataViewsAddress         = "\"MetadataViews\""
+	placeholderFlowTokenAddress             = "\"FlowToken\""
+	placeholderIDTableAddress               = "\"FlowIDTableStaking\""
+	placeholderBurnerAddress                = "\"Burner\""
+	placeholderStakingProxyAddress          = "\"StakingProxy\""
+	placeholderQCAddr                       = "\"FlowClusterQC\""
+	placeholderDKGAddr                      = "\"FlowDKG\""
+	placeholderEpochAddr                    = "\"FlowEpoch\""
+	placeholderFlowFeesAddress              = "\"FlowFees\""
+	placeholderStorageFeesAddress           = "\"FlowStorageFees\""
+	placeholderLockedTokensAddress          = "\"LockedTokens\""
+	placeholderStakingCollectionAddress     = "\"FlowStakingCollection\""
+	placeholderNodeVersionBeaconAddress     = "\"NodeVersionBeacon\""
+	placeholderFlowCallbackSchedulerAddress = "\"FlowCallbackScheduler\""
 )
 
 // Adds a `0x` prefix to the provided address string
@@ -293,6 +296,15 @@ func RandomBeaconHistory() []byte {
 	return assets.MustAsset(flowRandomBeaconHistoryFilename)
 }
 
+// FlowCallbackScheduler returns the FlowCallbackScheduler contract.
+func FlowCallbackScheduler(env templates.Environment) []byte {
+	code := assets.MustAssetString(flowCallbackSchedulerFilename)
+
+	code = templates.ReplaceAddresses(code, env)
+
+	return []byte(code)
+}
+
 // FlowContractAudits returns the deprecated FlowContractAudits contract.
 // This contract is no longer used on any network
 func FlowContractAudits() []byte {
@@ -368,6 +380,15 @@ func TestFlowFees(fungibleTokenAddress, flowTokenAddress, storageFeesAddress str
 	return []byte(code)
 }
 
+// TestFlowCallbackHandler returns the TestFlowCallbackHandler contract.
+func TestFlowCallbackHandler(env templates.Environment) []byte {
+	code := assets.MustAssetString(TESTflowCallbackHandlerFilename)
+
+	code = templates.ReplaceAddresses(code, env)
+
+	return []byte(code)
+}
+
 func ExampleToken(env templates.Environment) []byte {
 	return ftcontracts.ExampleToken(env.FungibleTokenAddress, env.MetadataViewsAddress, env.FungibleTokenMetadataViewsAddress)
 }

lib/go/contracts/contracts_test.go

@@ -41,6 +41,7 @@ func SetAllAddresses(env *templates.Environment) {
 	env.ServiceAccountAddress = fakeAddr
 	env.NodeVersionBeaconAddress = fakeAddr
 	env.RandomBeaconHistoryAddress = fakeAddr
+	env.FlowCallbackSchedulerAddress = fakeAddr
 }
 
 // Tests that a specific contract path should succeed when retrieving it
@@ -164,6 +165,23 @@ func TestStakingCollection(t *testing.T) {
 	assert.Contains(t, contract, "import LockedTokens from 0x")
 }
 
+func TestFlowCallbackScheduler(t *testing.T) {
+	env := templates.Environment{}
+	SetAllAddresses(&env)
+	contract := string(contracts.FlowCallbackScheduler(env))
+	GetCadenceContractShouldSucceed(t, contract)
+	assert.Contains(t, contract, "import FlowToken from 0x")
+	assert.Contains(t, contract, "import FlowFees from 0x")
+}
+
+func TestFlowCallbackHandler(t *testing.T) {
+	env := templates.Environment{}
+	SetAllAddresses(&env)
+	contract := string(contracts.TestFlowCallbackHandler(env))
+	GetCadenceContractShouldSucceed(t, contract)
+	assert.Contains(t, contract, "import FlowCallbackScheduler from 0x")
+}
+
 func TestNodeVersionBeacon(t *testing.T) {
 	contract := string(contracts.NodeVersionBeacon())
 	GetCadenceContractShouldSucceed(t, contract)

lib/go/contracts/go.mod

@@ -1,12 +1,12 @@
 module github.com/onflow/flow-core-contracts/lib/go/contracts
 
-go 1.22
+go 1.23.0
 
-toolchain go1.22.4
+toolchain go1.23.1
 
 require (
 	github.com/kevinburke/go-bindata v3.24.0+incompatible
-	github.com/onflow/flow-core-contracts/lib/go/templates v1.6.1-0.20250226163127-3c9723416637
+	github.com/onflow/flow-core-contracts/lib/go/templates v1.7.2-0.20250709181500-7b276f4ca1c8
 	github.com/onflow/flow-ft/lib/go/contracts v1.0.1
 	github.com/onflow/flow-go-sdk v1.0.0-preview.54
 	github.com/onflow/flow-nft/lib/go/contracts v1.2.4
@@ -59,10 +59,10 @@ require (
 	github.com/x448/float16 v0.8.4 // indirect
 	github.com/zeebo/blake3 v0.2.3 // indirect
 	go.opentelemetry.io/otel v1.24.0 // indirect
-	golang.org/x/crypto v0.19.0 // indirect
+	golang.org/x/crypto v0.35.0 // indirect
 	golang.org/x/exp v0.0.0-20240119083558-1b970713d09a // indirect
-	golang.org/x/sys v0.17.0 // indirect
-	golang.org/x/text v0.14.0 // indirect
+	golang.org/x/sys v0.30.0 // indirect
+	golang.org/x/text v0.22.0 // indirect
 	golang.org/x/xerrors v0.0.0-20231012003039-104605ab7028 // indirect
 	gonum.org/v1/gonum v0.14.0 // indirect
 	google.golang.org/protobuf v1.33.0 // indirect