fvm

package
v0.26.8-tx-result-an-fix Latest Latest
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 Go to latest Published: Jun 13, 2022 License: AGPL-3.0 Imports: 42 Imported by: 25

README

Flow Virtual Machine (FVM)

The Flow Virtual Machine (FVM) augments the Cadence runtime with the domain-specific functionality required by the Flow protocol.

Usage

Quickstart
import (
    "github.com/onflow/cadence/runtime"
    "github.com/onflow/flow-go/fvm"
    "github.com/onflow/flow-go/fvm/state"
    "github.com/onflow/flow-go/model/flow"
)

vm := fvm.New(runtime.NewInterpreterRuntime())

tx := flow.NewTransactionBody().
    SetScript([]byte(`transaction { execute { log("Hello, World!") } }`))

ctx := fvm.NewContext()
ledger := state.NewMapLedger()

txIndex := uint32(0)
txProc := fvm.Transaction(tx, txIndex)

err := vm.Run(ctx, txProc, ledger)
if err != nil {
  panic("fatal error during transaction procedure!")
}

fmt.Println(txProc.Logs[0]) // prints "Hello, World!"
Procedure

The FVM interacts with the Flow execution state by running atomic procedures against a shared ledger. A Procedure is an operation that can be applied to a Ledger.

Procedure Types
Transactions (Read/write)

A TransactionProcedure is an operation that mutates the ledger state.

A transaction procedure can be created from a flow.TransactionBody:

var tx flow.TransactionBody
var txIndex uint32

i := fvm.Transaction(tx, txIndex)

A transaction procedure has the following steps:

  1. Verify all transaction signatures against the current ledger state
  2. Validate and increment the proposal key sequence number
  3. Deduct transaction fee from the payer account
  4. Invoke transaction script with provided arguments and authorizers
Scripts (Read-only)

A ScriptProcedure is an operation that reads from the ledger state.

foo := fvm.Script([]byte(`fun main(): Int { return 42 }`))

A script can have optionally bound arguments:

script := fvm.Script([]byte(`fun main(x: Int): Int { x * 2 }`))

foo := script.WithArguments(argA)
bar := script.WithArguments(argB)
Contexts

The VM runs procedures inside of an execution context that defines the host functionality provided to the Cadence runtime. A Context instance is an immutable object, and any changes to a context must be made by spawning a new child context.

vm := fvm.New(runtime.NewInterpreterRuntime())

globalCtx := fvm.NewContext()

// create separate contexts for different blocks
block1Ctx := fvm.NewContextFromParent(globalCtx, fvm.WithBlockHeader(block1))
block2Ctx := fvm.NewContextFromParent(globalCtx, fvm.WithBlockHeader(block2))

// contexts can be safely used in parallel
go executeBlock(vm, block1Ctx)
go executeBlock(vm, block2Ctx)
Context Options

TODO: document context options

Design

The structure of the FVM package is intended to promote the following:

  • Determinism: the VM should be consistent and predictable, producing identical results given the same inputs.
  • Performance: the VM should expose functionality that allows the caller to exploit parallelism and pre-computation.
  • Flexibility: the VM should support a variety of use cases including not only execution and verification, but also developer tooling and network emulation.
Context

A Context is a reusable component that simply defines the parameters of an execution environment. For example, all transactions within the same block would share a common Context configured with the relevant block data.

Contexts can be arbitrarily nested. A child context inherits the parameters of its parent, but is free to override any parameters that it chooses.

HostEnvironment

A HostEnvironment is a short-lived component that is consumed by a procedure. A HostEnvironment is the interface through which the VM communicates with the Cadence runtime. The HostEnvironment provides information about the current Context and also collects logs, events and metrics emitted from the runtime.

Procedure Lifecycle

The diagram below illustrates the relationship between contexts, host environments and procedures. Multiple procedures can reuse the same context, each of which is supplied with a unique HostEnvironment instance.

fvm

TODO

  • Improve error handling
  • Create list of all missing test cases
  • Implement missing test cases
  • Documentation
    • Transaction validation (signatures, sequence numbers)
    • Fee payments
    • Address generation
    • Account management
    • Bootstrapping
    • Ledger usage

Open Questions

  • Currently the caller is responsible for providing the correct Ledger instance when running a procedure. When performing atomic operations in batches (i.e blocks or chunks), multiple ledgers are spawned in a hierarchy similar to that of multiple Context instances. Does it make sense for the fvm package to manage ledgers as well?

Documentation

Index

Constants

View Source 
const (
	DefaultComputationLimit             = 100_000        // 100K
	DefaultMemoryLimit                  = math.MaxUint64 //
	DefaultEventCollectionByteSizeLimit = 256_000        // 256KB
	DefaultMaxNumOfTxRetries            = 3
)
View Source 
const AccountKeyWeightThreshold = 1000

Variables

View Source 
var DefaultAccountCreationFee = func() cadence.UFix64 {
	value, err := cadence.NewUFix64("0.00100000")
	if err != nil {
		panic(fmt.Errorf("invalid default account creation fee: %w", err))
	}
	return value
}()
View Source 
var DefaultMinimumStorageReservation = func() cadence.UFix64 {
	value, err := cadence.NewUFix64("0.00100000")
	if err != nil {
		panic(fmt.Errorf("invalid default minimum storage reservation: %w", err))
	}
	return value
}()
View Source 
var DefaultStorageMBPerFLOW = func() cadence.UFix64 {
	value, err := cadence.NewUFix64("100.00000000")
	if err != nil {
		panic(fmt.Errorf("invalid default minimum storage reservation: %w", err))
	}
	return value
}()
View Source 
var DefaultTransactionFees = func() BootstrapProcedureFeeParameters {
	surgeFactor, err := cadence.NewUFix64("1.0")
	if err != nil {
		panic(fmt.Errorf("invalid default fee surge factor: %w", err))
	}
	inclusionEffortCost, err := cadence.NewUFix64("0.00001")
	if err != nil {
		panic(fmt.Errorf("invalid default fee effort cost: %w", err))
	}
	executionEffortCost, err := cadence.NewUFix64("0.0")
	if err != nil {
		panic(fmt.Errorf("invalid default fee effort cost: %w", err))
	}
	return BootstrapProcedureFeeParameters{
		SurgeFactor:         surgeFactor,
		InclusionEffortCost: inclusionEffortCost,
		ExecutionEffortCost: executionEffortCost,
	}
}()

DefaultTransactionFees are the default transaction fee parameters if transaction fees are on. surge factor is 1.0, inclusion effort cost is 0.0001 (because the static inclusion effort is 1.0) and execution effort cost is 0.0 because dynamic execution fees are off If they are off (which is the default behaviour) that means the transaction fees are 0.0.

Functions

func AccountAvailableBalanceInvocation added in v0.23.2 

func AccountAvailableBalanceInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(address common.Address) (cadence.Value, error)

AccountAvailableBalanceInvocation prepares a function that calls get available balance on the storage fees contract

func AccountBalanceInvocation added in v0.23.2 

func AccountBalanceInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(address common.Address) (cadence.Value, error)

AccountBalanceInvocation prepares a function that calls get available balance on the service account

func AccountStorageCapacityInvocation added in v0.23.2 

func AccountStorageCapacityInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(address common.Address) (cadence.Value, error)

AccountStorageCapacityInvocation prepares a function that calls get storage capacity on the storage fees contract

func DeductTransactionFeesInvocation added in v0.23.2 

func DeductTransactionFeesInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(payer flow.Address, inclusionEffort uint64, executionEffort uint64) (cadence.Value, error)

DeductTransactionFeesInvocation prepares a function that calls fee deduction on the service account

func FlowFeesAddress added in v0.14.0 

func FlowFeesAddress(chain flow.Chain) flow.Address

func FlowTokenAddress 

func FlowTokenAddress(chain flow.Chain) flow.Address

func FungibleTokenAddress 

func FungibleTokenAddress(chain flow.Chain) flow.Address

func NewInterpreterRuntime added in v0.15.1 

func NewInterpreterRuntime(options ...runtime.Option) runtime.Runtime

func SetupNewAccountInvocation added in v0.23.2 

func SetupNewAccountInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(flowAddress flow.Address, payer common.Address) (cadence.Value, error)

SetupNewAccountInvocation prepares a function that calls new account setup on the service account

func UseContractAuditVoucherInvocation added in v0.23.9 

func UseContractAuditVoucherInvocation(
	env Environment,
	traceSpan opentracing.Span,
) func(address common.Address, code string) (bool, error)

UseContractAuditVoucherInvocation prepares a function that can use a contract deployment audit voucher

func WithFlowEventHandleOptions added in v0.26.3 

func WithFlowEventHandleOptions(feho ...handler.FlowEventHandlerOption) func(inv *TransactionInvoker)

Types

type Blocks 

type Blocks interface {
	// ByHeight returns the block at the given height in the chain ending in `header` (or finalized
	// if `header` is nil). This enables querying un-finalized blocks by height with respect to the
	// chain defined by the block we are executing.
	ByHeightFrom(height uint64, header *flow.Header) (*flow.Header, error)
}

func NewBlockFinder added in v0.13.0 

func NewBlockFinder(storage storage.Headers) Blocks

NewBlockFinder constructs a new block finder

type BlocksFinder added in v0.13.0 

type BlocksFinder struct {
	// contains filtered or unexported fields
}

BlocksFinder finds blocks and return block headers

func (*BlocksFinder) ByHeightFrom added in v0.13.0 

func (b *BlocksFinder) ByHeightFrom(height uint64, header *flow.Header) (*flow.Header, error)

ByHeightFrom returns the block header by height.

type BootstrapProcedure 

type BootstrapProcedure struct {
	// contains filtered or unexported fields
}

A BootstrapProcedure is an invokable that can be used to bootstrap the ledger state with the default accounts and contracts required by the Flow virtual machine.

func Bootstrap 

func Bootstrap(
	serviceAccountPublicKey flow.AccountPublicKey,
	opts ...BootstrapProcedureOption,
) *BootstrapProcedure

Bootstrap returns a new BootstrapProcedure instance configured with the provided genesis parameters.

func (*BootstrapProcedure) ComputationLimit added in v0.25.2 

func (proc *BootstrapProcedure) ComputationLimit(_ Context) uint64

func (*BootstrapProcedure) MemoryLimit added in v0.25.2 

func (proc *BootstrapProcedure) MemoryLimit(_ Context) uint64

func (*BootstrapProcedure) Run 

func (b *BootstrapProcedure) Run(vm *VirtualMachine, ctx Context, sth *state.StateHolder, programs *programs.Programs) error

type BootstrapProcedureFeeParameters added in v0.25.2 

type BootstrapProcedureFeeParameters struct {
	SurgeFactor         cadence.UFix64
	InclusionEffortCost cadence.UFix64
	ExecutionEffortCost cadence.UFix64
}

type BootstrapProcedureOption added in v0.14.0 

type BootstrapProcedureOption func(*BootstrapProcedure) *BootstrapProcedure

func WithAccountCreationFee added in v0.14.0 

func WithAccountCreationFee(fee cadence.UFix64) BootstrapProcedureOption

func WithEpochConfig added in v0.20.0 

func WithEpochConfig(epochConfig epochs.EpochConfig) BootstrapProcedureOption

func WithExecutionEffortWeights added in v0.25.5 

func WithExecutionEffortWeights(weights weightedMeter.ExecutionEffortWeights) BootstrapProcedureOption

func WithExecutionMemoryLimit added in v0.26.2 

func WithExecutionMemoryLimit(limit uint64) BootstrapProcedureOption

func WithExecutionMemoryWeights added in v0.26.0 

func WithExecutionMemoryWeights(weights weightedMeter.ExecutionMemoryWeights) BootstrapProcedureOption

func WithIdentities added in v0.20.0 

func WithIdentities(identities flow.IdentityList) BootstrapProcedureOption

func WithInitialTokenSupply added in v0.14.0 

func WithInitialTokenSupply(supply cadence.UFix64) BootstrapProcedureOption

func WithMinimumStorageReservation added in v0.14.0 

func WithMinimumStorageReservation(reservation cadence.UFix64) BootstrapProcedureOption

func WithRestrictedAccountCreationEnabled added in v0.17.6 

func WithRestrictedAccountCreationEnabled(enabled cadence.Bool) BootstrapProcedureOption

func WithRestrictedContractDeployment added in v0.26.0 

func WithRestrictedContractDeployment(restricted *bool) BootstrapProcedureOption

func WithRootBlock added in v0.20.0 

func WithRootBlock(rootBlock *flow.Header) BootstrapProcedureOption

func WithStorageMBPerFLOW added in v0.16.1 

func WithStorageMBPerFLOW(ratio cadence.UFix64) BootstrapProcedureOption

func WithTransactionFee added in v0.14.0 

func WithTransactionFee(fees BootstrapProcedureFeeParameters) BootstrapProcedureOption

type Context 

type Context struct {
	Chain                        flow.Chain
	Blocks                       Blocks
	Metrics                      handler.MetricsReporter
	Tracer                       module.Tracer
	ComputationLimit             uint64
	MemoryLimit                  uint64
	MaxStateKeySize              uint64
	MaxStateValueSize            uint64
	MaxStateInteractionSize      uint64
	EventCollectionByteSizeLimit uint64
	MaxNumOfTxRetries            uint8
	BlockHeader                  *flow.Header
	ServiceAccountEnabled        bool
	// Depricated: RestrictedDeploymentEnabled is deprecated use SetIsContractDeploymentRestrictedTransaction instead.
	// Can be removed after all networks are migrated to SetIsContractDeploymentRestrictedTransaction
	RestrictedDeploymentEnabled      bool
	RestrictedContractRemovalEnabled bool
	LimitAccountStorage              bool
	TransactionFeesEnabled           bool
	CadenceLoggingEnabled            bool
	EventCollectionEnabled           bool
	ServiceEventCollectionEnabled    bool
	AccountFreezeAvailable           bool
	ExtensiveTracing                 bool
	TransactionProcessors            []TransactionProcessor
	ScriptProcessors                 []ScriptProcessor
	Logger                           zerolog.Logger
}

A Context defines a set of execution parameters used by the virtual machine.

func NewContext 

func NewContext(logger zerolog.Logger, opts ...Option) Context

NewContext initializes a new execution context with the provided options.

func NewContextFromParent 

func NewContextFromParent(parent Context, opts ...Option) Context

NewContextFromParent spawns a child execution context with the provided options.

type ContractFunctionInvoker added in v0.25.2 

type ContractFunctionInvoker struct {
	// contains filtered or unexported fields
}

func NewContractFunctionInvoker added in v0.25.2 

func NewContractFunctionInvoker(
	contractLocation common.AddressLocation,
	functionName string,
	arguments []interpreter.Value,
	argumentTypes []sema.Type,
	logger zerolog.Logger) *ContractFunctionInvoker

func (*ContractFunctionInvoker) Invoke added in v0.25.2 

func (i *ContractFunctionInvoker) Invoke(env Environment, parentTraceSpan opentracing.Span) (cadence.Value, error)

type Environment added in v0.22.4 

type Environment interface {
	Context() *Context
	VM() *VirtualMachine
	runtime.Interface
}

Environment accepts a context and a virtual machine instance and provides cadence runtime interface methods to the runtime.

type NoopBlockFinder added in v0.20.0 

type NoopBlockFinder struct{}

NoopBlockFinder implements the Blocks interface. It is used in the bootstrapping process.

func (*NoopBlockFinder) ByHeightFrom added in v0.20.0 

func (f *NoopBlockFinder) ByHeightFrom(_ uint64, _ *flow.Header) (*flow.Header, error)

type Option 

type Option func(ctx Context) Context

An Option sets a configuration parameter for a virtual machine context.

func WithAccountFreezeAvailable added in v0.15.1 

func WithAccountFreezeAvailable(accountFreezeAvailable bool) Option

WithAccountFreezeAvailable sets availability of account freeze function for a virtual machine context.

With this option set to true, a setAccountFreeze function will be enabled for transactions processed by the VM

func WithAccountStorageLimit added in v0.14.0 

func WithAccountStorageLimit(enabled bool) Option

WithAccountStorageLimit enables or disables checking if account storage used is over its storage capacity

func WithBlockHeader 

func WithBlockHeader(header *flow.Header) Option

WithBlockHeader sets the block header for a virtual machine context.

The VM uses the header to provide current block information to the Cadence runtime, as well as to seed the pseudorandom number generator.

func WithBlocks 

func WithBlocks(blocks Blocks) Option

WithBlocks sets the block storage provider for a virtual machine context.

The VM uses the block storage provider to provide historical block information to the Cadence runtime.

func WithCadenceLogging added in v0.13.1 

func WithCadenceLogging(enabled bool) Option

WithCadenceLogging enables or disables Cadence logging for a virtual machine context.

func WithChain 

func WithChain(chain flow.Chain) Option

WithChain sets the chain parameters for a virtual machine context.

func WithComputationLimit added in v0.25.2 

func WithComputationLimit(limit uint64) Option

WithComputationLimit sets the computation limit for a virtual machine context.

func WithEventCollectionSizeLimit added in v0.13.1 

func WithEventCollectionSizeLimit(limit uint64) Option

WithEventCollectionSizeLimit sets the event collection byte size limit for a virtual machine context.

func WithExtensiveTracing added in v0.16.0 

func WithExtensiveTracing() Option

WithExtensiveTracing sets the extensive tracing

func WithGasLimit 

func WithGasLimit(limit uint64) Option

WithGasLimit sets the computation limit for a virtual machine context. @depricated, please use WithComputationLimit instead.

func WithMaxStateInteractionSize added in v0.14.0 

func WithMaxStateInteractionSize(limit uint64) Option

WithMaxStateInteractionSize sets the byte size limit for total interaction with ledger. this prevents attacks such as reading all large registers

func WithMaxStateKeySize added in v0.14.0 

func WithMaxStateKeySize(limit uint64) Option

WithMaxStateKeySize sets the byte size limit for ledger keys

func WithMaxStateValueSize added in v0.14.0 

func WithMaxStateValueSize(limit uint64) Option

WithMaxStateValueSize sets the byte size limit for ledger values

func WithMemoryLimit added in v0.25.2 

func WithMemoryLimit(limit uint64) Option

WithMemoryLimit sets the memory limit for a virtual machine context.

func WithMetricsReporter added in v0.17.6 

func WithMetricsReporter(mr handler.MetricsReporter) Option

WithMetricsReporter sets the metrics collector for a virtual machine context.

A metrics collector is used to gather metrics reported by the Cadence runtime.

func WithRestrictedContractRemovalEnabled added in v0.26.5 

func WithRestrictedContractRemovalEnabled(enabled bool) Option

WithRestrictedContractRemovalEnabled enables or disables restricted contract removal for a virtual machine context.

func WithRestrictedDeployment 

func WithRestrictedDeployment(enabled bool) Option

WithRestrictedDeployment enables or disables restricted contract deployment for a virtual machine context. Warning! this would be overridden with the flag stored on chain. this is just a fallback value

func WithServiceAccount 

func WithServiceAccount(enabled bool) Option

WithServiceAccount enables or disables calls to the Flow service account.

func WithServiceEventCollectionEnabled added in v0.17.1 

func WithServiceEventCollectionEnabled() Option

WithServiceEventCollectionEnabled enables service event collection

func WithTracer added in v0.14.5 

func WithTracer(tr module.Tracer) Option

WithTracer sets the tracer for a virtual machine context.

func WithTransactionFeesEnabled added in v0.17.1 

func WithTransactionFeesEnabled(enabled bool) Option

WithTransactionFeesEnabled enables or disables deduction of transaction fees

func WithTransactionProcessors 

func WithTransactionProcessors(processors ...TransactionProcessor) Option

WithTransactionProcessors sets the transaction processors for a virtual machine context.

type Procedure 

type Procedure interface {
	Run(vm *VirtualMachine, ctx Context, sth *state.StateHolder, programs *programs.Programs) error
	ComputationLimit(ctx Context) uint64
	MemoryLimit(ctx Context) uint64
}

An Procedure is an operation (or set of operations) that reads or writes ledger state.

type ScriptEnv added in v0.20.0 

type ScriptEnv struct {
	// contains filtered or unexported fields
}

ScriptEnv is a read-only mostly used for executing scripts.

func NewScriptEnvironment added in v0.20.0 

func NewScriptEnvironment(
	reqContext context.Context,
	fvmContext Context,
	vm *VirtualMachine,
	sth *state.StateHolder,
	programs *programs.Programs,
) *ScriptEnv

func (*ScriptEnv) AddAccountKey added in v0.20.0 

func (e *ScriptEnv) AddAccountKey(_ runtime.Address, _ *runtime.PublicKey, _ runtime.HashAlgorithm, _ int) (*runtime.AccountKey, error)

func (*ScriptEnv) AddEncodedAccountKey added in v0.20.0 

func (e *ScriptEnv) AddEncodedAccountKey(_ runtime.Address, _ []byte) error

func (*ScriptEnv) AllocateStorageIndex added in v0.21.0 

func (e *ScriptEnv) AllocateStorageIndex(owner []byte) (atree.StorageIndex, error)

AllocateStorageIndex allocates new storage index under the owner accounts to store a new register

func (*ScriptEnv) BLSAggregatePublicKeys added in v0.25.0 

func (e *ScriptEnv) BLSAggregatePublicKeys(keys []*runtime.PublicKey) (*runtime.PublicKey, error)

func (*ScriptEnv) BLSAggregateSignatures added in v0.25.0 

func (e *ScriptEnv) BLSAggregateSignatures(sigs [][]byte) ([]byte, error)

func (*ScriptEnv) BLSVerifyPOP added in v0.25.0 

func (e *ScriptEnv) BLSVerifyPOP(pk *runtime.PublicKey, sig []byte) (bool, error)

func (*ScriptEnv) Commit added in v0.20.0 

func (e *ScriptEnv) Commit() ([]programs.ContractUpdateKey, error)

Commit commits changes and return a list of updated keys

func (*ScriptEnv) ComputationUsed added in v0.25.2 

func (e *ScriptEnv) ComputationUsed() uint64

func (*ScriptEnv) Context added in v0.23.2 

func (e *ScriptEnv) Context() *Context

func (*ScriptEnv) CreateAccount added in v0.20.0 

func (e *ScriptEnv) CreateAccount(_ runtime.Address) (address runtime.Address, err error)

func (*ScriptEnv) DecodeArgument added in v0.20.0 

func (e *ScriptEnv) DecodeArgument(b []byte, t cadence.Type) (cadence.Value, error)

func (*ScriptEnv) EmitEvent added in v0.20.0 

func (e *ScriptEnv) EmitEvent(_ cadence.Event) error

func (*ScriptEnv) Events added in v0.20.0 

func (e *ScriptEnv) Events() []flow.Event

func (*ScriptEnv) GenerateUUID added in v0.20.0 

func (e *ScriptEnv) GenerateUUID() (uint64, error)

func (*ScriptEnv) GetAccountAvailableBalance added in v0.20.0 

func (e *ScriptEnv) GetAccountAvailableBalance(address common.Address) (value uint64, err error)

func (*ScriptEnv) GetAccountBalance added in v0.20.0 

func (e *ScriptEnv) GetAccountBalance(address common.Address) (value uint64, err error)

func (*ScriptEnv) GetAccountContractCode added in v0.20.0 

func (e *ScriptEnv) GetAccountContractCode(address runtime.Address, name string) (code []byte, err error)

func (*ScriptEnv) GetAccountContractNames added in v0.21.0 

func (e *ScriptEnv) GetAccountContractNames(address runtime.Address) ([]string, error)

func (*ScriptEnv) GetAccountKey added in v0.20.0 

func (e *ScriptEnv) GetAccountKey(address runtime.Address, index int) (*runtime.AccountKey, error)

func (*ScriptEnv) GetBlockAtHeight added in v0.20.0 

func (e *ScriptEnv) GetBlockAtHeight(height uint64) (runtime.Block, bool, error)

GetBlockAtHeight returns the block at the given height.

func (*ScriptEnv) GetCode added in v0.20.0 

func (e *ScriptEnv) GetCode(location runtime.Location) ([]byte, error)

func (*ScriptEnv) GetCurrentBlockHeight added in v0.20.0 

func (e *ScriptEnv) GetCurrentBlockHeight() (uint64, error)

GetCurrentBlockHeight returns the current block height.

func (*ScriptEnv) GetProgram added in v0.20.0 

func (e *ScriptEnv) GetProgram(location common.Location) (*interpreter.Program, error)

func (*ScriptEnv) GetSigningAccounts added in v0.20.0 

func (e *ScriptEnv) GetSigningAccounts() ([]runtime.Address, error)

func (*ScriptEnv) GetStorageCapacity added in v0.20.0 

func (e *ScriptEnv) GetStorageCapacity(address common.Address) (value uint64, err error)

func (*ScriptEnv) GetStorageUsed added in v0.20.0 

func (e *ScriptEnv) GetStorageUsed(address common.Address) (value uint64, err error)

func (*ScriptEnv) GetValue added in v0.20.0 

func (e *ScriptEnv) GetValue(owner, key []byte) ([]byte, error)

func (*ScriptEnv) Hash added in v0.20.0 

func (e *ScriptEnv) Hash(data []byte, tag string, hashAlgorithm runtime.HashAlgorithm) ([]byte, error)

func (*ScriptEnv) ImplementationDebugLog added in v0.20.0 

func (e *ScriptEnv) ImplementationDebugLog(message string) error

func (*ScriptEnv) Logs added in v0.20.0 

func (e *ScriptEnv) Logs() []string

func (*ScriptEnv) MemoryUsed added in v0.26.0 

func (e *ScriptEnv) MemoryUsed() uint64

func (*ScriptEnv) MeterComputation added in v0.25.2 

func (e *ScriptEnv) MeterComputation(kind common.ComputationKind, intensity uint) error

func (*ScriptEnv) MeterMemory added in v0.26.0 

func (e *ScriptEnv) MeterMemory(usage common.MemoryUsage) error

func (*ScriptEnv) ProgramChecked added in v0.20.0 

func (e *ScriptEnv) ProgramChecked(location common.Location, duration time.Duration)

func (*ScriptEnv) ProgramInterpreted added in v0.20.0 

func (e *ScriptEnv) ProgramInterpreted(location common.Location, duration time.Duration)

func (*ScriptEnv) ProgramLog added in v0.20.0 

func (e *ScriptEnv) ProgramLog(message string) error

func (*ScriptEnv) ProgramParsed added in v0.20.0 

func (e *ScriptEnv) ProgramParsed(location common.Location, duration time.Duration)

func (*ScriptEnv) RecordTrace added in v0.22.0 

func (e *ScriptEnv) RecordTrace(operation string, location common.Location, duration time.Duration, logs []opentracing.LogRecord)

func (*ScriptEnv) RemoveAccountContractCode added in v0.20.0 

func (e *ScriptEnv) RemoveAccountContractCode(_ runtime.Address, _ string) (err error)

func (*ScriptEnv) ResolveLocation added in v0.20.0 

func (e *ScriptEnv) ResolveLocation(
	identifiers []runtime.Identifier,
	location runtime.Location,
) ([]runtime.ResolvedLocation, error)

func (*ScriptEnv) ResourceOwnerChanged added in v0.25.0 

func (e *ScriptEnv) ResourceOwnerChanged(
	*interpreter.Interpreter,
	*interpreter.CompositeValue,
	common.Address,
	common.Address,
)

func (*ScriptEnv) RevokeAccountKey added in v0.20.0 

func (e *ScriptEnv) RevokeAccountKey(_ runtime.Address, _ int) (*runtime.AccountKey, error)

func (*ScriptEnv) RevokeEncodedAccountKey added in v0.20.0 

func (e *ScriptEnv) RevokeEncodedAccountKey(_ runtime.Address, _ int) (publicKey []byte, err error)

func (*ScriptEnv) SetProgram added in v0.20.0 

func (e *ScriptEnv) SetProgram(location common.Location, program *interpreter.Program) error

func (*ScriptEnv) SetValue added in v0.20.0 

func (e *ScriptEnv) SetValue(owner, key, value []byte) error

TODO disable SetValue for scripts, right now the view changes are discarded

func (*ScriptEnv) UnsafeRandom added in v0.20.0 

func (e *ScriptEnv) UnsafeRandom() (uint64, error)

UnsafeRandom returns a random uint64, where the process of random number derivation is not cryptographically secure.

func (*ScriptEnv) UpdateAccountContractCode added in v0.20.0 

func (e *ScriptEnv) UpdateAccountContractCode(_ runtime.Address, _ string, _ []byte) (err error)

func (*ScriptEnv) VM added in v0.23.2 

func (e *ScriptEnv) VM() *VirtualMachine

func (*ScriptEnv) ValidatePublicKey added in v0.20.0 

func (e *ScriptEnv) ValidatePublicKey(pk *runtime.PublicKey) error

func (*ScriptEnv) ValueDecoded added in v0.20.0 

func (e *ScriptEnv) ValueDecoded(duration time.Duration)

func (*ScriptEnv) ValueEncoded added in v0.20.0 

func (e *ScriptEnv) ValueEncoded(duration time.Duration)

func (*ScriptEnv) ValueExists added in v0.20.0 

func (e *ScriptEnv) ValueExists(owner, key []byte) (exists bool, err error)

func (*ScriptEnv) VerifySignature added in v0.20.0 

func (e *ScriptEnv) VerifySignature(
	signature []byte,
	tag string,
	signedData []byte,
	publicKey []byte,
	signatureAlgorithm runtime.SignatureAlgorithm,
	hashAlgorithm runtime.HashAlgorithm,
) (bool, error)

type ScriptInvoker added in v0.23.2 

type ScriptInvoker struct{}

func NewScriptInvoker added in v0.23.2 

func NewScriptInvoker() ScriptInvoker

func (ScriptInvoker) Process added in v0.23.2 

func (i ScriptInvoker) Process(
	vm *VirtualMachine,
	ctx Context,
	proc *ScriptProcedure,
	sth *state.StateHolder,
	programs *programs.Programs,
) error

type ScriptProcedure 

type ScriptProcedure struct {
	ID             flow.Identifier
	Script         []byte
	Arguments      [][]byte
	RequestContext context.Context
	Value          cadence.Value
	Logs           []string
	Events         []flow.Event
	GasUsed        uint64
	MemoryUsed     uint64
	Err            errors.Error
}

func NewScriptWithContextAndArgs added in v0.26.0 

func NewScriptWithContextAndArgs(code []byte, reqContext context.Context, args ...[]byte) *ScriptProcedure

func Script 

func Script(code []byte) *ScriptProcedure

func (*ScriptProcedure) ComputationLimit added in v0.25.2 

func (proc *ScriptProcedure) ComputationLimit(ctx Context) uint64

func (*ScriptProcedure) MemoryLimit added in v0.25.2 

func (proc *ScriptProcedure) MemoryLimit(ctx Context) uint64

func (*ScriptProcedure) Run 

func (proc *ScriptProcedure) Run(vm *VirtualMachine, ctx Context, sth *state.StateHolder, programs *programs.Programs) error

func (*ScriptProcedure) WithArguments 

func (proc *ScriptProcedure) WithArguments(args ...[]byte) *ScriptProcedure

func (*ScriptProcedure) WithRequestContext added in v0.26.0 

func (proc *ScriptProcedure) WithRequestContext(reqContext context.Context) *ScriptProcedure

type ScriptProcessor 

type ScriptProcessor interface {
	Process(*VirtualMachine, Context, *ScriptProcedure, *state.StateHolder, *programs.Programs) error
}

type TransactionAccountFrozenChecker added in v0.15.1 

type TransactionAccountFrozenChecker struct{}

func NewTransactionAccountFrozenChecker added in v0.15.1 

func NewTransactionAccountFrozenChecker() *TransactionAccountFrozenChecker

func (*TransactionAccountFrozenChecker) Process added in v0.15.1 

func (c *TransactionAccountFrozenChecker) Process(
	_ *VirtualMachine,
	_ *Context,
	proc *TransactionProcedure,
	sth *state.StateHolder,
	_ *programs.Programs,
) error

type TransactionAccountFrozenEnabler added in v0.15.1 

type TransactionAccountFrozenEnabler struct{}

func NewTransactionAccountFrozenEnabler added in v0.15.1 

func NewTransactionAccountFrozenEnabler() *TransactionAccountFrozenEnabler

func (*TransactionAccountFrozenEnabler) Process added in v0.15.1 

func (c *TransactionAccountFrozenEnabler) Process(
	_ *VirtualMachine,
	ctx *Context,
	proc *TransactionProcedure,
	_ *state.StateHolder,
	_ *programs.Programs,
) error

type TransactionEnv added in v0.20.0 

type TransactionEnv struct {
	// contains filtered or unexported fields
}

TransactionEnv is a read-write environment used for executing flow transactions.

func NewTransactionEnvironment added in v0.20.0 

func NewTransactionEnvironment(
	ctx Context,
	vm *VirtualMachine,
	sth *state.StateHolder,
	programs *programs.Programs,
	tx *flow.TransactionBody,
	txIndex uint32,
	traceSpan opentracing.Span,
	eventHandlerOptions ...handler.FlowEventHandlerOption,
) (*TransactionEnv, error)

func (*TransactionEnv) AddAccountKey added in v0.20.0 

func (e *TransactionEnv) AddAccountKey(
	address runtime.Address,
	publicKey *runtime.PublicKey,
	hashAlgo runtime.HashAlgorithm,
	weight int,
) (
	*runtime.AccountKey,
	error,
)

AddAccountKey adds a public key to an existing account.

This function returns an error if the specified account does not exist or if the key insertion fails.

func (*TransactionEnv) AddEncodedAccountKey added in v0.20.0 

func (e *TransactionEnv) AddEncodedAccountKey(address runtime.Address, publicKey []byte) error

AddEncodedAccountKey adds an encoded public key to an existing account.

This function returns an error if the specified account does not exist or if the key insertion fails.

func (*TransactionEnv) AllocateStorageIndex added in v0.21.0 

func (e *TransactionEnv) AllocateStorageIndex(owner []byte) (atree.StorageIndex, error)

AllocateStorageIndex allocates new storage index under the owner accounts to store a new register

func (*TransactionEnv) BLSAggregatePublicKeys added in v0.25.0 

func (e *TransactionEnv) BLSAggregatePublicKeys(keys []*runtime.PublicKey) (*runtime.PublicKey, error)

func (*TransactionEnv) BLSAggregateSignatures added in v0.25.0 

func (e *TransactionEnv) BLSAggregateSignatures(sigs [][]byte) ([]byte, error)

func (*TransactionEnv) BLSVerifyPOP added in v0.25.0 

func (e *TransactionEnv) BLSVerifyPOP(pk *runtime.PublicKey, sig []byte) (bool, error)

func (*TransactionEnv) Commit added in v0.20.0 

func (e *TransactionEnv) Commit() ([]programs.ContractUpdateKey, error)

Commit commits changes and return a list of updated keys

func (*TransactionEnv) ComputationUsed added in v0.25.2 

func (e *TransactionEnv) ComputationUsed() uint64

func (*TransactionEnv) Context added in v0.20.0 

func (e *TransactionEnv) Context() *Context

func (*TransactionEnv) CreateAccount added in v0.20.0 

func (e *TransactionEnv) CreateAccount(payer runtime.Address) (address runtime.Address, err error)

func (*TransactionEnv) DecodeArgument added in v0.20.0 

func (e *TransactionEnv) DecodeArgument(b []byte, _ cadence.Type) (cadence.Value, error)

func (*TransactionEnv) EmitEvent added in v0.20.0 

func (e *TransactionEnv) EmitEvent(event cadence.Event) error

func (*TransactionEnv) Events added in v0.20.0 

func (e *TransactionEnv) Events() []flow.Event

func (*TransactionEnv) GenerateUUID added in v0.20.0 

func (e *TransactionEnv) GenerateUUID() (uint64, error)

func (*TransactionEnv) GetAccountAvailableBalance added in v0.20.0 

func (e *TransactionEnv) GetAccountAvailableBalance(address common.Address) (value uint64, err error)

func (*TransactionEnv) GetAccountBalance added in v0.20.0 

func (e *TransactionEnv) GetAccountBalance(address common.Address) (value uint64, err error)

func (*TransactionEnv) GetAccountContractCode added in v0.20.0 

func (e *TransactionEnv) GetAccountContractCode(address runtime.Address, name string) (code []byte, err error)

func (*TransactionEnv) GetAccountContractNames added in v0.21.0 

func (e *TransactionEnv) GetAccountContractNames(address runtime.Address) ([]string, error)

func (*TransactionEnv) GetAccountKey added in v0.20.0 

func (e *TransactionEnv) GetAccountKey(address runtime.Address, keyIndex int) (*runtime.AccountKey, error)

GetAccountKey retrieves a public key by index from an existing account.

This function returns a nil key with no errors, if a key doesn't exist at the given index. An error is returned if the specified account does not exist, the provided index is not valid, or if the key retrieval fails.

func (*TransactionEnv) GetAccountsAuthorizedForContractRemoval added in v0.26.0 

func (e *TransactionEnv) GetAccountsAuthorizedForContractRemoval() []common.Address

GetAccountsAuthorizedForContractRemoval returns a list of addresses authorized to remove contracts

func (*TransactionEnv) GetAccountsAuthorizedForContractUpdate added in v0.26.0 

func (e *TransactionEnv) GetAccountsAuthorizedForContractUpdate() []common.Address

GetAccountsAuthorizedForContractUpdate returns a list of addresses authorized to update/deploy contracts

func (*TransactionEnv) GetAuthorizedAccounts added in v0.26.0 

func (e *TransactionEnv) GetAuthorizedAccounts(path cadence.Path) []common.Address

GetAuthorizedAccounts returns a list of addresses authorized by the service account. Used to determine which accounts are permitted to deploy, update, or remove contracts.

It reads a storage path from service account and parse the addresses. If any issue occurs on the process (missing registers, stored value properly not set), it gracefully handles it and falls back to default behaviour (only service account be authorized).

func (*TransactionEnv) GetBlockAtHeight added in v0.20.0 

func (e *TransactionEnv) GetBlockAtHeight(height uint64) (runtime.Block, bool, error)

GetBlockAtHeight returns the block at the given height.

func (*TransactionEnv) GetCode added in v0.20.0 

func (e *TransactionEnv) GetCode(location runtime.Location) ([]byte, error)

func (*TransactionEnv) GetCurrentBlockHeight added in v0.20.0 

func (e *TransactionEnv) GetCurrentBlockHeight() (uint64, error)

GetCurrentBlockHeight returns the current block height.

func (*TransactionEnv) GetIsContractDeploymentRestricted added in v0.26.0 

func (e *TransactionEnv) GetIsContractDeploymentRestricted() (restricted bool, defined bool)

GetIsContractDeploymentRestricted returns if contract deployment restriction is defined in the state and the value of it

func (*TransactionEnv) GetProgram added in v0.20.0 

func (e *TransactionEnv) GetProgram(location common.Location) (*interpreter.Program, error)

func (*TransactionEnv) GetSigningAccounts added in v0.20.0 

func (e *TransactionEnv) GetSigningAccounts() ([]runtime.Address, error)

func (*TransactionEnv) GetStorageCapacity added in v0.20.0 

func (e *TransactionEnv) GetStorageCapacity(address common.Address) (value uint64, err error)

func (*TransactionEnv) GetStorageUsed added in v0.20.0 

func (e *TransactionEnv) GetStorageUsed(address common.Address) (value uint64, err error)

func (*TransactionEnv) GetValue added in v0.20.0 

func (e *TransactionEnv) GetValue(owner, key []byte) ([]byte, error)

func (*TransactionEnv) Hash added in v0.20.0 

func (e *TransactionEnv) Hash(data []byte, tag string, hashAlgorithm runtime.HashAlgorithm) ([]byte, error)

func (*TransactionEnv) ImplementationDebugLog added in v0.20.0 

func (e *TransactionEnv) ImplementationDebugLog(message string) error

func (*TransactionEnv) Logs added in v0.20.0 

func (e *TransactionEnv) Logs() []string

func (*TransactionEnv) MemoryUsed added in v0.26.0 

func (e *TransactionEnv) MemoryUsed() uint64

func (*TransactionEnv) MeterComputation added in v0.25.2 

func (e *TransactionEnv) MeterComputation(kind common.ComputationKind, intensity uint) error

func (*TransactionEnv) MeterMemory added in v0.26.0 

func (e *TransactionEnv) MeterMemory(usage common.MemoryUsage) error

func (*TransactionEnv) ProgramChecked added in v0.20.0 

func (e *TransactionEnv) ProgramChecked(location common.Location, duration time.Duration)

func (*TransactionEnv) ProgramInterpreted added in v0.20.0 

func (e *TransactionEnv) ProgramInterpreted(location common.Location, duration time.Duration)

func (*TransactionEnv) ProgramLog added in v0.20.0 

func (e *TransactionEnv) ProgramLog(message string) error

func (*TransactionEnv) ProgramParsed added in v0.20.0 

func (e *TransactionEnv) ProgramParsed(location common.Location, duration time.Duration)

func (*TransactionEnv) RecordTrace added in v0.22.0 

func (e *TransactionEnv) RecordTrace(operation string, location common.Location, duration time.Duration, logs []opentracing.LogRecord)

func (*TransactionEnv) RemoveAccountContractCode added in v0.20.0 

func (e *TransactionEnv) RemoveAccountContractCode(address runtime.Address, name string) (err error)

func (*TransactionEnv) ResolveLocation added in v0.20.0 

func (e *TransactionEnv) ResolveLocation(
	identifiers []runtime.Identifier,
	location runtime.Location,
) ([]runtime.ResolvedLocation, error)

func (*TransactionEnv) ResourceOwnerChanged added in v0.25.0 

func (e *TransactionEnv) ResourceOwnerChanged(
	*interpreter.Interpreter,
	*interpreter.CompositeValue,
	common.Address,
	common.Address,
)

func (*TransactionEnv) RevokeAccountKey added in v0.20.0 

func (e *TransactionEnv) RevokeAccountKey(address runtime.Address, keyIndex int) (*runtime.AccountKey, error)

RevokeAccountKey revokes a public key by index from an existing account, and returns the revoked key.

This function returns a nil key with no errors, if a key doesn't exist at the given index. An error is returned if the specified account does not exist, the provided index is not valid, or if the key revoking fails.

func (*TransactionEnv) RevokeEncodedAccountKey added in v0.20.0 

func (e *TransactionEnv) RevokeEncodedAccountKey(address runtime.Address, index int) (publicKey []byte, err error)

RevokeEncodedAccountKey revokes a public key by index from an existing account.

This function returns an error if the specified account does not exist, the provided key is invalid, or if key revoking fails.

func (*TransactionEnv) ServiceEvents added in v0.20.0 

func (e *TransactionEnv) ServiceEvents() []flow.Event

func (*TransactionEnv) SetAccountFrozen added in v0.20.0 

func (e *TransactionEnv) SetAccountFrozen(address common.Address, frozen bool) error

func (*TransactionEnv) SetProgram added in v0.20.0 

func (e *TransactionEnv) SetProgram(location common.Location, program *interpreter.Program) error

func (*TransactionEnv) SetValue added in v0.20.0 

func (e *TransactionEnv) SetValue(owner, key, value []byte) error

func (*TransactionEnv) TxID added in v0.20.0 

func (e *TransactionEnv) TxID() flow.Identifier

func (*TransactionEnv) TxIndex added in v0.20.0 

func (e *TransactionEnv) TxIndex() uint32

func (*TransactionEnv) UnsafeRandom added in v0.20.0 

func (e *TransactionEnv) UnsafeRandom() (uint64, error)

UnsafeRandom returns a random uint64, where the process of random number derivation is not cryptographically secure.

func (*TransactionEnv) UpdateAccountContractCode added in v0.20.0 

func (e *TransactionEnv) UpdateAccountContractCode(address runtime.Address, name string, code []byte) (err error)

func (*TransactionEnv) VM added in v0.20.0 

func (e *TransactionEnv) VM() *VirtualMachine

func (*TransactionEnv) ValidatePublicKey added in v0.20.0 

func (e *TransactionEnv) ValidatePublicKey(pk *runtime.PublicKey) error

func (*TransactionEnv) ValueDecoded added in v0.20.0 

func (e *TransactionEnv) ValueDecoded(duration time.Duration)

func (*TransactionEnv) ValueEncoded added in v0.20.0 

func (e *TransactionEnv) ValueEncoded(duration time.Duration)

func (*TransactionEnv) ValueExists added in v0.20.0 

func (e *TransactionEnv) ValueExists(owner, key []byte) (exists bool, err error)

func (*TransactionEnv) VerifySignature added in v0.20.0 

func (e *TransactionEnv) VerifySignature(
	signature []byte,
	tag string,
	signedData []byte,
	publicKey []byte,
	signatureAlgorithm runtime.SignatureAlgorithm,
	hashAlgorithm runtime.HashAlgorithm,
) (bool, error)

type TransactionInvoker added in v0.23.2 

type TransactionInvoker struct {
	// contains filtered or unexported fields
}

func NewTransactionInvoker added in v0.23.2 

func NewTransactionInvoker(logger zerolog.Logger, options ...TransactionInvokerOption) *TransactionInvoker

func (*TransactionInvoker) Process added in v0.23.2 

func (i *TransactionInvoker) Process(
	vm *VirtualMachine,
	ctx *Context,
	proc *TransactionProcedure,
	sth *state.StateHolder,
	programs *programs.Programs,
) (processErr error)

type TransactionInvokerOption added in v0.26.3 

type TransactionInvokerOption func(invoker *TransactionInvoker)

type TransactionProcedure 

type TransactionProcedure struct {
	ID              flow.Identifier
	Transaction     *flow.TransactionBody
	TxIndex         uint32
	Logs            []string
	Events          []flow.Event
	ServiceEvents   []flow.Event
	ComputationUsed uint64
	MemoryUsed      uint64
	Err             errors.Error
	Retried         int
	TraceSpan       opentracing.Span
}

func Transaction 

func Transaction(tx *flow.TransactionBody, txIndex uint32) *TransactionProcedure

func (*TransactionProcedure) ComputationLimit added in v0.25.2 

func (proc *TransactionProcedure) ComputationLimit(ctx Context) uint64

func (*TransactionProcedure) MemoryLimit added in v0.25.2 

func (proc *TransactionProcedure) MemoryLimit(ctx Context) uint64

func (*TransactionProcedure) Run 

func (proc *TransactionProcedure) Run(vm *VirtualMachine, ctx Context, st *state.StateHolder, programs *programs.Programs) error

func (*TransactionProcedure) SetTraceSpan added in v0.14.5 

func (proc *TransactionProcedure) SetTraceSpan(traceSpan opentracing.Span)

type TransactionProcessor 

type TransactionProcessor interface {
	Process(*VirtualMachine, *Context, *TransactionProcedure, *state.StateHolder, *programs.Programs) error
}

type TransactionSequenceNumberChecker 

type TransactionSequenceNumberChecker struct{}

func NewTransactionSequenceNumberChecker 

func NewTransactionSequenceNumberChecker() *TransactionSequenceNumberChecker

func (*TransactionSequenceNumberChecker) Process 

func (c *TransactionSequenceNumberChecker) Process(
	_ *VirtualMachine,
	ctx *Context,
	proc *TransactionProcedure,
	sth *state.StateHolder,
	_ *programs.Programs,
) error

type TransactionSignatureVerifier 

type TransactionSignatureVerifier struct {
	KeyWeightThreshold int
}

func NewTransactionSignatureVerifier 

func NewTransactionSignatureVerifier(keyWeightThreshold int) *TransactionSignatureVerifier

func (*TransactionSignatureVerifier) Process 

func (v *TransactionSignatureVerifier) Process(
	_ *VirtualMachine,
	ctx *Context,
	proc *TransactionProcedure,
	sth *state.StateHolder,
	_ *programs.Programs,
) error

type TransactionStorageLimiter added in v0.14.0 

type TransactionStorageLimiter struct{}

func NewTransactionStorageLimiter added in v0.14.0 

func NewTransactionStorageLimiter() *TransactionStorageLimiter

func (*TransactionStorageLimiter) CheckLimits added in v0.20.0 

func (d *TransactionStorageLimiter) CheckLimits(
	env Environment,
	addresses []flow.Address,
) error

type VirtualMachine 

type VirtualMachine struct {
	Runtime runtime.Runtime
}

A VirtualMachine augments the Cadence runtime with Flow host functionality.

func NewVirtualMachine added in v0.15.1 

func NewVirtualMachine(rt runtime.Runtime) *VirtualMachine

NewVirtualMachine creates a new virtual machine instance with the provided runtime.

func (*VirtualMachine) GetAccount 

func (vm *VirtualMachine) GetAccount(ctx Context, address flow.Address, v state.View, programs *programs.Programs) (*flow.Account, error)

GetAccount returns an account by address or an error if none exists.

func (*VirtualMachine) Run 

func (vm *VirtualMachine) Run(ctx Context, proc Procedure, v state.View, programs *programs.Programs) (err error)

Run runs a procedure against a ledger in the given context.

Source Files

View all Source files

Directories

Path Synopsis
basic
noop
weighted
state
Package systemcontracts stores canonical address locations for all system smart contracts and service events.
 Package systemcontracts stores canonical address locations for all system smart contracts and service events.

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