fvm

package
v0.31.9-HCU-test Latest Latest
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 Go to latest Published: Jun 15, 2023 License: AGPL-3.0 Imports: 31 Imported by: 24

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/storage/state"
    "github.com/onflow/flow-go/model/flow"
)

vm := fvm.NewVirtualMachine()

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

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

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

executionSnapshot, output, 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 (
	AccountKeyWeightThreshold = 1000

	DefaultComputationLimit   = 100_000 // 100K
	DefaultMemoryLimit        = math.MaxUint64
	DefaultMaxInteractionSize = 20_000_000 // ~20MB
)
View Source 
const (
	BootstrapProcedureType   = ProcedureType("bootstrap")
	TransactionProcedureType = ProcedureType("transaction")
	ScriptProcedureType      = ProcedureType("script")
)

Variables

View Source 
var (
	DefaultAccountCreationFee = mustParseUFix64(
		"account creation fee",
		"0.00100000")

	DefaultMinimumStorageReservation = mustParseUFix64(
		"minimum storage reservation",
		"0.00100000")

	DefaultStorageMBPerFLOW = mustParseUFix64(
		"storage mb per flow",
		"100.00000000")

	// 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.
	DefaultTransactionFees = BootstrapProcedureFeeParameters{
		SurgeFactor: mustParseUFix64("fee surge factor", "1.0"),
		InclusionEffortCost: mustParseUFix64(
			"fee inclusion effort cost",
			"0.00001"),
		ExecutionEffortCost: mustParseUFix64(
			"fee execution effort cost",
			"0.0"),
	}

	// DefaultVersionFreezePeriod is the default NodeVersionBeacon freeze period -
	// the number of blocks in the future where the version changes are frozen.
	DefaultVersionFreezePeriod = cadence.UInt64(1000)
)

Functions

func FlowTokenAddress 

func FlowTokenAddress(chain flow.Chain) flow.Address

func FungibleTokenAddress 

func FungibleTokenAddress(chain flow.Chain) flow.Address

func GetExecutionEffortWeights added in v0.27.0 

func GetExecutionEffortWeights(
	env environment.Environment,
	service common.Address,
) (
	computationWeights meter.ExecutionEffortWeights,
	err error,
)

GetExecutionEffortWeights reads stored execution effort weights from the service account

func GetExecutionMemoryLimit added in v0.27.0 

func GetExecutionMemoryLimit(
	env environment.Environment,
	service common.Address,
) (
	memoryLimit uint64,
	err error,
)

GetExecutionMemoryLimit reads the stored execution memory limit from the service account

func GetExecutionMemoryWeights added in v0.27.0 

func GetExecutionMemoryWeights(
	env environment.Environment,
	service common.Address,
) (
	memoryWeights meter.ExecutionMemoryWeights,
	err error,
)

GetExecutionMemoryWeights reads stored execution memory weights from the service account

func ProcedureStateParameters added in v0.31.0 

func ProcedureStateParameters(
	ctx Context,
	proc Procedure,
) state.StateParameters

func Run added in v0.29.0 

func Run(executor ProcedureExecutor) error

Types

type BootstrapAccountKeys added in v0.27.0 

type BootstrapAccountKeys struct {
	ServiceAccountPublicKeys       []flow.AccountPublicKey
	FungibleTokenAccountPublicKeys []flow.AccountPublicKey
	FlowTokenAccountPublicKeys     []flow.AccountPublicKey
	FlowFeesAccountPublicKeys      []flow.AccountPublicKey
	NodeAccountPublicKeys          []flow.AccountPublicKey
}

type BootstrapParams added in v0.29.0 

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

type BootstrapProcedure 

type BootstrapProcedure struct {
	BootstrapParams
}

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) ExecutionTime added in v0.28.0 

func (proc *BootstrapProcedure) ExecutionTime() logical.Time

func (*BootstrapProcedure) MemoryLimit added in v0.25.2 

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

func (*BootstrapProcedure) NewExecutor added in v0.29.0 

func (b *BootstrapProcedure) NewExecutor(
	ctx Context,
	txnState storage.TransactionPreparer,
) ProcedureExecutor

func (*BootstrapProcedure) ShouldDisableMemoryAndInteractionLimits added in v0.28.0 

func (proc *BootstrapProcedure) ShouldDisableMemoryAndInteractionLimits(_ Context) bool

func (BootstrapProcedure) Type added in v0.28.0 

func (BootstrapProcedure) Type() ProcedureType

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 WithBootstrapAccountKeys added in v0.27.0 

func WithBootstrapAccountKeys(keys BootstrapAccountKeys) BootstrapProcedureOption

WithBootstrapAccountKeys sets the public keys of the accounts that will be created during bootstrapping by default all accounts are created with the ServiceAccountPublicKey specified when calling `Bootstrap`.

func WithEpochConfig added in v0.20.0 

func WithEpochConfig(epochConfig epochs.EpochConfig) BootstrapProcedureOption

func WithExecutionEffortWeights added in v0.25.5 

func WithExecutionEffortWeights(weights meter.ExecutionEffortWeights) BootstrapProcedureOption

func WithExecutionMemoryLimit added in v0.26.2 

func WithExecutionMemoryLimit(limit uint64) BootstrapProcedureOption

func WithExecutionMemoryWeights added in v0.26.0 

func WithExecutionMemoryWeights(weights meter.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 {
	// DisableMemoryAndInteractionLimits will override memory and interaction
	// limits and set them to MaxUint64, effectively disabling these limits.
	DisableMemoryAndInteractionLimits bool
	ComputationLimit                  uint64
	MemoryLimit                       uint64
	MaxStateKeySize                   uint64
	MaxStateValueSize                 uint64
	MaxStateInteractionSize           uint64

	TransactionExecutorParams

	DerivedBlockData *derived.DerivedBlockData

	tracing.TracerSpan

	environment.EnvironmentParams
}

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

func NewContext 

func NewContext(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 MeterParamOverridesComputer added in v0.29.0 

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

func NewMeterParamOverridesComputer added in v0.29.0 

func NewMeterParamOverridesComputer(
	ctx Context,
	txnState storage.TransactionPreparer,
) MeterParamOverridesComputer

func (MeterParamOverridesComputer) Compute added in v0.29.0 

func (computer MeterParamOverridesComputer) Compute(
	_ state.NestedTransactionPreparer,
	_ struct{},
) (
	derived.MeterParamOverrides,
	error,
)

type Option 

type Option func(ctx Context) Context

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

func WithAccountKeyWeightThreshold added in v0.29.0 

func WithAccountKeyWeightThreshold(threshold int) Option

WithAccountKeyWeightThreshold sets the key weight threshold used for authorization checks. If the threshold is a negative number, signature verification is skipped.

Note: This is set only by tests

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 WithAuthorizationChecksEnabled added in v0.29.0 

func WithAuthorizationChecksEnabled(enabled bool) Option

WithAuthorizationCheckxEnabled enables or disables pre-execution authorization checks.

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 environment.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 WithContractDeploymentRestricted added in v0.27.0 

func WithContractDeploymentRestricted(enabled bool) Option

WithRestrictedContractDeployment 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 WithContractRemovalRestricted added in v0.27.0 

func WithContractRemovalRestricted(enabled bool) Option

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

func WithDerivedBlockData added in v0.29.0 

func WithDerivedBlockData(derivedBlockData *derived.DerivedBlockData) Option

WithDerivedBlockData sets the derived data cache storage to be used by the transaction/script.

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 WithEventEncoder added in v0.29.0 

func WithEventEncoder(encoder environment.EventEncoder) Option

WithEventEncoder sets events encoder to be used for encoding events emitted during execution

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 WithLogger added in v0.28.0 

func WithLogger(logger zerolog.Logger) Option

WithLogger sets the context logger

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 WithMemoryAndInteractionLimitsDisabled added in v0.28.0 

func WithMemoryAndInteractionLimitsDisabled() Option

WithMemoryAndInteractionLimitsDisabled will override memory and interaction limits and set them to MaxUint64, effectively disabling these limits.

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 environment.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 WithReusableCadenceRuntimePool added in v0.28.0 

func WithReusableCadenceRuntimePool(
	pool reusableRuntime.ReusableCadenceRuntimePool,
) Option

WithReusableCadenceRuntimePool set the (shared) RedusableCadenceRuntimePool use for creating the cadence runtime.

func WithSequenceNumberCheckAndIncrementEnabled added in v0.29.0 

func WithSequenceNumberCheckAndIncrementEnabled(enabled bool) Option

WithSequenceNumberCheckAndIncrementEnabled enables or disables pre-execution sequence number check / increment.

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 WithSpan added in v0.30.0 

func WithSpan(span otelTrace.Span) Option

WithSpan sets the trace span for a virtual machine context.

func WithTracer added in v0.14.5 

func WithTracer(tr module.Tracer) Option

WithTracer sets the tracer for a virtual machine context.

func WithTransactionBodyExecutionEnabled added in v0.29.0 

func WithTransactionBodyExecutionEnabled(enabled bool) Option

WithTransactionBodyExecutionEnabled enables or disables the transaction body execution.

Note: This is disabled only by tests

func WithTransactionFeesEnabled added in v0.17.1 

func WithTransactionFeesEnabled(enabled bool) Option

WithTransactionFeesEnabled enables or disables deduction of transaction fees

type Procedure 

type Procedure interface {
	NewExecutor(
		ctx Context,
		txnState storage.TransactionPreparer,
	) ProcedureExecutor

	ComputationLimit(ctx Context) uint64
	MemoryLimit(ctx Context) uint64
	ShouldDisableMemoryAndInteractionLimits(ctx Context) bool

	Type() ProcedureType

	// For transactions, the execution time is TxIndex.  For scripts, the
	// execution time is EndOfBlockExecutionTime.
	ExecutionTime() logical.Time
}

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

type ProcedureExecutor added in v0.29.0 

type ProcedureExecutor interface {
	Preprocess() error
	Execute() error
	Cleanup()

	Output() ProcedureOutput
}

type ProcedureOutput added in v0.30.0 

type ProcedureOutput struct {
	// Output by both transaction and script.
	Logs                   []string
	Events                 flow.EventsList
	ServiceEvents          flow.EventsList
	ConvertedServiceEvents flow.ServiceEventList
	ComputationUsed        uint64
	ComputationIntensities meter.MeteredComputationIntensities
	MemoryEstimate         uint64
	Err                    errors.CodedError

	// Output only by script.
	Value cadence.Value
}

func (*ProcedureOutput) PopulateEnvironmentValues added in v0.30.0 

func (output *ProcedureOutput) PopulateEnvironmentValues(
	env environment.Environment,
) error

type ProcedureType added in v0.28.0 

type ProcedureType string

type ScriptProcedure 

type ScriptProcedure struct {
	ID             flow.Identifier
	Script         []byte
	Arguments      [][]byte
	RequestContext context.Context
}

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) ExecutionTime added in v0.28.0 

func (proc *ScriptProcedure) ExecutionTime() logical.Time

func (*ScriptProcedure) MemoryLimit added in v0.25.2 

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

func (*ScriptProcedure) NewExecutor added in v0.29.0 

func (proc *ScriptProcedure) NewExecutor(
	ctx Context,
	txnState storage.TransactionPreparer,
) ProcedureExecutor

func (*ScriptProcedure) ShouldDisableMemoryAndInteractionLimits added in v0.28.0 

func (proc *ScriptProcedure) ShouldDisableMemoryAndInteractionLimits(
	ctx Context,
) bool

func (ScriptProcedure) Type added in v0.28.0 

func (ScriptProcedure) Type() ProcedureType

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 TransactionExecutorParams added in v0.29.0 

type TransactionExecutorParams struct {
	AuthorizationChecksEnabled bool

	SequenceNumberCheckAndIncrementEnabled bool

	// If AccountKeyWeightThreshold is set to a negative number, signature
	// verification is skipped during authorization checks.
	//
	// Note: This is set only by tests
	AccountKeyWeightThreshold int

	// Note: This is disabled only by tests
	TransactionBodyExecutionEnabled bool
}

func DefaultTransactionExecutorParams added in v0.29.0 

func DefaultTransactionExecutorParams() TransactionExecutorParams

type TransactionPayerBalanceChecker added in v0.29.0 

type TransactionPayerBalanceChecker struct{}

func (TransactionPayerBalanceChecker) CheckPayerBalanceAndReturnMaxFees added in v0.29.0 

func (_ TransactionPayerBalanceChecker) CheckPayerBalanceAndReturnMaxFees(
	proc *TransactionProcedure,
	txnState storage.TransactionPreparer,
	env environment.Environment,
) (uint64, error)

type TransactionProcedure 

type TransactionProcedure struct {
	ID          flow.Identifier
	Transaction *flow.TransactionBody
	TxIndex     uint32
}

func NewTransaction added in v0.30.0 

func NewTransaction(
	txnId flow.Identifier,
	txnIndex uint32,
	txnBody *flow.TransactionBody,
) *TransactionProcedure

func Transaction 

func Transaction(
	txn *flow.TransactionBody,
	txnIndex uint32,
) *TransactionProcedure

func (*TransactionProcedure) ComputationLimit added in v0.25.2 

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

func (*TransactionProcedure) ExecutionTime added in v0.28.0 

func (proc *TransactionProcedure) ExecutionTime() logical.Time

func (*TransactionProcedure) MemoryLimit added in v0.25.2 

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

func (*TransactionProcedure) NewExecutor added in v0.29.0 

func (proc *TransactionProcedure) NewExecutor(
	ctx Context,
	txnState storage.TransactionPreparer,
) ProcedureExecutor

func (*TransactionProcedure) ShouldDisableMemoryAndInteractionLimits added in v0.28.0 

func (proc *TransactionProcedure) ShouldDisableMemoryAndInteractionLimits(
	ctx Context,
) bool

func (TransactionProcedure) Type added in v0.28.0 

func (TransactionProcedure) Type() ProcedureType

type TransactionSequenceNumberChecker 

type TransactionSequenceNumberChecker struct{}

func (TransactionSequenceNumberChecker) CheckAndIncrementSequenceNumber added in v0.29.0 

func (c TransactionSequenceNumberChecker) CheckAndIncrementSequenceNumber(
	tracer tracing.TracerSpan,
	proc *TransactionProcedure,
	txnState storage.TransactionPreparer,
) error

type TransactionStorageLimiter added in v0.14.0 

type TransactionStorageLimiter struct{}

func (TransactionStorageLimiter) CheckStorageLimits added in v0.29.0 

func (limiter TransactionStorageLimiter) CheckStorageLimits(
	env environment.Environment,
	snapshot *snapshot.ExecutionSnapshot,
	payer flow.Address,
	maxTxFees uint64,
) error

CheckStorageLimits checks each account that had its storage written to during a transaction, that its storage used is less than its storage capacity. Storage used is an FVM register and is easily accessible. Storage capacity is calculated by the FlowStorageFees contract from the account's flow balance.

The payers balance is considered to be maxTxFees lower that its actual balance, due to the fact that the fee deduction step happens after the storage limit check.

type TransactionVerifier added in v0.27.0 

type TransactionVerifier struct {
	VerificationConcurrency int
}

TransactionVerifier verifies the content of the transaction by checking there is no double signature all signatures are valid all accounts provides enoguh weights

if KeyWeightThreshold is set to a negative number, signature verification is skipped

func (*TransactionVerifier) CheckAuthorization added in v0.29.0 

func (v *TransactionVerifier) CheckAuthorization(
	tracer tracing.TracerSpan,
	proc *TransactionProcedure,
	txnState storage.TransactionPreparer,
	keyWeightThreshold int,
) error

type VM added in v0.30.0 

type VM interface {
	NewExecutor(
		Context,
		Procedure,
		storage.TransactionPreparer,
	) ProcedureExecutor

	Run(
		Context,
		Procedure,
		snapshot.StorageSnapshot,
	) (
		*snapshot.ExecutionSnapshot,
		ProcedureOutput,
		error,
	)

	GetAccount(Context, flow.Address, snapshot.StorageSnapshot) (*flow.Account, error)
}

VM runs procedures

type VirtualMachine 

type VirtualMachine struct {
}

A VirtualMachine augments the Cadence runtime with Flow host functionality.

func NewVirtualMachine added in v0.15.1 

func NewVirtualMachine() *VirtualMachine

func (*VirtualMachine) GetAccount 

func (vm *VirtualMachine) GetAccount(
	ctx Context,
	address flow.Address,
	storageSnapshot snapshot.StorageSnapshot,
) (
	*flow.Account,
	error,
)

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

func (*VirtualMachine) NewExecutor added in v0.31.0 

func (vm *VirtualMachine) NewExecutor(
	ctx Context,
	proc Procedure,
	txn storage.TransactionPreparer,
) ProcedureExecutor

func (*VirtualMachine) Run 

func (vm *VirtualMachine) Run(
	ctx Context,
	proc Procedure,
	storageSnapshot snapshot.StorageSnapshot,
) (
	*snapshot.ExecutionSnapshot,
	ProcedureOutput,
	error,
)

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

Source Files

View all Source files

Directories

Path Synopsis
generate-wrappers
mock
testutil
derived
errors
logical
primary
snapshot
state
testutils
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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