Documentation ¶
Overview ¶
Package simulation implements a full fledged Cosmos SDK application used for executing simulation test suites.
Simulation App ¶
The SimApp type defines an application used for running extensive simulation testing suites. It contains all core modules, including governance, staking, slashing, and distribution.
Simulation is executed with various inputs including the number of blocks to simulate, the block size, whether the app should commit or not, the invariant checking period, and a seed which is used as a source of pseudo-randomness.
In addition to the various inputs, simulation runs mainly in three modes:
1. Completely random where the initial state, module parameters and simulation parameters are pseudo-randomly generated.
2. From a genesis file where the initial state and the module parameters are defined. This mode is helpful for running simulations on a known state such as a live network export where a new (mostly likely breaking) version of the application needs to be tested.
3. From a params file where the initial state is pseudo-randomly generated but the module and simulation parameters can be provided manually. This allows for a more controlled and deterministic simulation setup while allowing the state space to still be pseudo-randomly simulated.
The simulation test suite also supports testing determinism and import/export functionality.
Randomness ¶
Currently, simulation uses a single seed (integer) as a source for a PRNG by which all random operations are executed from. Any call to the PRNG changes all future operations as the internal state of the PRNG is modified. For example, if a new message type is created and needs to be simulated, the new introduced PRNG call will change all subsequent operations.
This may can often be problematic when testing fixes to simulation faults. One current solution to this is to use a params file as mentioned above. In the future the simulation suite is expected to support a series of PRNGs that can be used uniquely per module and simulation component so that they will not effect each others state execution outcome.
Usage ¶
To execute a completely pseudo-random simulation:
$ go test -mod=readonly github.com/cosmos/cosmos-sdk/simapp \ -run=TestFullAppSimulation \ -Enabled=true \ -NumBlocks=100 \ -BlockSize=200 \ -Commit=true \ -Seed=99 \ -Period=5 \ -v -timeout 24h
To execute simulation from a genesis file:
$ go test -mod=readonly github.com/cosmos/cosmos-sdk/simapp \ -run=TestFullAppSimulation \ -Enabled=true \ -NumBlocks=100 \ -BlockSize=200 \ -Commit=true \ -Seed=99 \ -Period=5 \ -Genesis=/path/to/genesis.json \ -v -timeout 24h
To execute simulation from a simulation params file:
$ go test -mod=readonly github.com/cosmos/cosmos-sdk/simapp \ -run=TestFullAppSimulation \ -Enabled=true \ -NumBlocks=100 \ -BlockSize=200 \ -Commit=true \ -Seed=99 \ -Period=5 \ -Params=/path/to/params.json \ -v -timeout 24h
To export the simulation params to a file at a given block height:
$ go test -mod=readonly github.com/cosmos/cosmos-sdk/simapp \ -run=TestFullAppSimulation \ -Enabled=true \ -NumBlocks=100 \ -BlockSize=200 \ -Commit=true \ -Seed=99 \ -Period=5 \ -ExportParamsPath=/path/to/params.json \ -ExportParamsHeight=50 \ -v -timeout 24h
To export the simulation app state (i.e genesis) to a file:
$ go test -mod=readonly github.com/cosmos/cosmos-sdk/simapp \ -run=TestFullAppSimulation \ -Enabled=true \ -NumBlocks=100 \ -BlockSize=200 \ -Commit=true \ -Seed=99 \ -Period=5 \ -ExportStatePath=/path/to/genesis.json \ v -timeout 24h
Params ¶
Params that are provided to simulation from a JSON file are used to used to set both module parameters and simulation parameters. See sim_test.go for the full set of parameters that can be provided.
Index ¶
- Constants
- func CreateTransitionMatrix(weights [][]int) (simulation.TransitionMatrix, error)
- func GenAndDeliverTx(txCtx OperationInput, fees sdk.Coins) (simtypes.OperationMsg, []simtypes.FutureOperation, error)
- func GenAndDeliverTxWithRandFees(txCtx OperationInput) (simtypes.OperationMsg, []simtypes.FutureOperation, error)
- func GetMemberOfInitialState(r *rand.Rand, weights []int) int
- func NewSimParamChange(subspace, key string, simVal simulation.SimValFn) simulation.ParamChange
- func NewWeightedProposalContent(appParamsKey string, defaultWeight int, ...) simulation.WeightedProposalContent
- func RandomRequestBeginBlock(r *rand.Rand, params Params, validators mockValidators, pastTimes []time.Time, ...) abci.RequestBeginBlock
- type AccountKeeper
- type BankKeeper
- type DummyLogWriter
- type EventStats
- type LogWriter
- type OperationEntry
- func BeginBlockEntry(height int64) OperationEntry
- func EndBlockEntry(height int64) OperationEntry
- func MsgEntry(height, order int64, opMsg simulation.OperationMsg) OperationEntry
- func NewOperationEntry(entry string, height, order int64, op json.RawMessage) OperationEntry
- func QueuedMsgEntry(height int64, opMsg simulation.OperationMsg) OperationEntry
- type OperationInput
- type OperationQueue
- type ParamChange
- type Params
- func (p Params) BlockSizeTransitionMatrix() simulation.TransitionMatrix
- func (p Params) EvidenceFraction() float64
- func (p Params) InitialLivenessWeightings() []int
- func (p Params) LivenessTransitionMatrix() simulation.TransitionMatrix
- func (p Params) NumKeys() int
- func (p Params) PastEvidenceFraction() float64
- type StandardLogWriter
- type TransitionMatrix
- type WeightedOperation
- type WeightedOperations
- type WeightedProposalContent
Constants ¶
const ( BeginBlockEntryKind = "begin_block" EndBlockEntryKind = "end_block" MsgEntryKind = "msg" QueuedMsgEntryKind = "queued_msg" )
entry kinds for use within OperationEntry
const AverageBlockTime = 6 * time.Second
Variables ¶
This section is empty.
Functions ¶
func CreateTransitionMatrix ¶
func CreateTransitionMatrix(weights [][]int) (simulation.TransitionMatrix, error)
CreateTransitionMatrix creates a transition matrix from the provided weights. TODO: Provide example usage
func GenAndDeliverTx ¶
func GenAndDeliverTx(txCtx OperationInput, fees sdk.Coins) (simtypes.OperationMsg, []simtypes.FutureOperation, error)
GenAndDeliverTx generates a transactions and delivers it.
func GenAndDeliverTxWithRandFees ¶
func GenAndDeliverTxWithRandFees(txCtx OperationInput) (simtypes.OperationMsg, []simtypes.FutureOperation, error)
GenAndDeliverTxWithRandFees generates a transaction with a random fee and delivers it.
func GetMemberOfInitialState ¶
GetMemberOfInitialState takes an initial array of weights, of size n. It returns a weighted random number in [0,n).
func NewSimParamChange ¶
func NewSimParamChange(subspace, key string, simVal simulation.SimValFn) simulation.ParamChange
NewSimParamChange creates a new ParamChange instance
func NewWeightedProposalContent ¶
func NewWeightedProposalContent(appParamsKey string, defaultWeight int, contentSimulatorFn simulation.ContentSimulatorFn) simulation.WeightedProposalContent
func RandomRequestBeginBlock ¶
func RandomRequestBeginBlock(r *rand.Rand, params Params, validators mockValidators, pastTimes []time.Time, pastVoteInfos [][]abci.VoteInfo, event func(route, op, evResult string), header tmproto.Header, ) abci.RequestBeginBlock
RandomRequestBeginBlock generates a list of signing validators according to the provided list of validators, signing fraction, and evidence fraction
Types ¶
type AccountKeeper ¶
AccountKeeper defines the expected account keeper used for simulations (noalias)
type BankKeeper ¶
BankKeeper defines the expected interface needed to retrieve account balances.
type EventStats ¶
EventStats defines an object that keeps a tally of each event that has occurred during a simulation.
func NewEventStats ¶
func NewEventStats() EventStats
NewEventStats creates a new empty EventStats object
func (EventStats) ExportJSON ¶
func (es EventStats) ExportJSON(path string)
ExportJSON saves the event stats as a JSON file on a given path
func (EventStats) Print ¶
func (es EventStats) Print(w io.Writer)
Print the event stats in JSON format.
func (EventStats) Tally ¶
func (es EventStats) Tally(route, op, evResult string)
Tally increases the count of a simulation event.
type LogWriter ¶
type LogWriter interface { AddEntry(OperationEntry) PrintLogs() }
log writter
func NewLogWriter ¶
LogWriter - return a dummy or standard log writer given the testingmode
type OperationEntry ¶
type OperationEntry struct { EntryKind string `json:"entry_kind" yaml:"entry_kind"` Height int64 `json:"height" yaml:"height"` Order int64 `json:"order" yaml:"order"` Operation json.RawMessage `json:"operation" yaml:"operation"` }
OperationEntry - an operation entry for logging (ex. BeginBlock, EndBlock, XxxMsg, etc)
func BeginBlockEntry ¶
func BeginBlockEntry(height int64) OperationEntry
BeginBlockEntry - operation entry for begin block
func EndBlockEntry ¶
func EndBlockEntry(height int64) OperationEntry
EndBlockEntry - operation entry for end block
func MsgEntry ¶
func MsgEntry(height, order int64, opMsg simulation.OperationMsg) OperationEntry
MsgEntry - operation entry for standard msg
func NewOperationEntry ¶
func NewOperationEntry(entry string, height, order int64, op json.RawMessage) OperationEntry
NewOperationEntry creates a new OperationEntry instance
func QueuedMsgEntry ¶
func QueuedMsgEntry(height int64, opMsg simulation.OperationMsg) OperationEntry
QueuedMsgEntry creates an operation entry for a given queued message.
func (OperationEntry) MustMarshal ¶
func (oe OperationEntry) MustMarshal() json.RawMessage
MustMarshal marshals the operation entry, panic on error.
type OperationInput ¶
type OperationInput struct { R *rand.Rand App *baseapp.BaseApp TxGen client.TxConfig Cdc *codec.ProtoCodec Msg sdk.Msg MsgType string CoinsSpentInMsg sdk.Coins Context sdk.Context SimAccount simtypes.Account AccountKeeper AccountKeeper Bankkeeper BankKeeper ModuleName string }
OperationInput is a struct that holds all the needed values to generate a tx and deliver it
type OperationQueue ¶
type OperationQueue map[int][]simulation.Operation
OperationQueue defines an object for a queue of operations
func NewOperationQueue ¶
func NewOperationQueue() OperationQueue
NewOperationQueue creates a new OperationQueue instance.
type ParamChange ¶
type ParamChange struct {
// contains filtered or unexported fields
}
ParamChange defines the object used for simulating parameter change proposals
func (ParamChange) ComposedKey ¶
func (spc ParamChange) ComposedKey() string
ComposedKey creates a new composed key for the param change proposal
func (ParamChange) Key ¶
func (spc ParamChange) Key() string
func (ParamChange) SimValue ¶
func (spc ParamChange) SimValue() simulation.SimValFn
func (ParamChange) Subspace ¶
func (spc ParamChange) Subspace() string
type Params ¶
type Params struct {
// contains filtered or unexported fields
}
Params define the parameters necessary for running the simulations
func RandomParams ¶
RandomParams returns random simulation parameters
func SimulateFromSeed ¶
func SimulateFromSeed( tb testing.TB, w io.Writer, app *baseapp.BaseApp, appStateFn simulation.AppStateFn, randAccFn simulation.RandomAccountFn, ops WeightedOperations, blockedAddrs map[string]bool, config simulation.Config, cdc codec.JSONCodec, ) (stopEarly bool, exportedParams Params, err error)
SimulateFromSeed tests an application by running the provided operations, testing the provided invariants, but using the provided config.Seed. TODO: split this monster function up
func (Params) BlockSizeTransitionMatrix ¶
func (p Params) BlockSizeTransitionMatrix() simulation.TransitionMatrix
func (Params) EvidenceFraction ¶
func (Params) InitialLivenessWeightings ¶
func (Params) LivenessTransitionMatrix ¶
func (p Params) LivenessTransitionMatrix() simulation.TransitionMatrix
func (Params) PastEvidenceFraction ¶
type StandardLogWriter ¶
type StandardLogWriter struct {
OpEntries []OperationEntry `json:"op_entries" yaml:"op_entries"`
}
log writter
func (*StandardLogWriter) AddEntry ¶
func (lw *StandardLogWriter) AddEntry(opEntry OperationEntry)
add an entry to the log writter
func (*StandardLogWriter) PrintLogs ¶
func (lw *StandardLogWriter) PrintLogs()
PrintLogs - print the logs to a simulation file
type TransitionMatrix ¶
type TransitionMatrix struct {
// contains filtered or unexported fields
}
TransitionMatrix is _almost_ a left stochastic matrix. It is technically not one due to not normalizing the column values. In the future, if we want to find the steady state distribution, it will be quite easy to normalize these values to get a stochastic matrix. Floats aren't currently used as the default due to non-determinism across architectures
type WeightedOperation ¶
type WeightedOperation struct {
// contains filtered or unexported fields
}
WeightedOperation is an operation with associated weight. This is used to bias the selection operation within the simulator.
func NewWeightedOperation ¶
func NewWeightedOperation(weight int, op simulation.Operation) WeightedOperation
NewWeightedOperation creates a new WeightedOperation instance
func (WeightedOperation) Op ¶
func (w WeightedOperation) Op() simulation.Operation
func (WeightedOperation) Weight ¶
func (w WeightedOperation) Weight() int
type WeightedOperations ¶
type WeightedOperations []simulation.WeightedOperation
WeightedOperations is the group of all weighted operations to simulate.
type WeightedProposalContent ¶
type WeightedProposalContent struct {
// contains filtered or unexported fields
}
WeightedProposalContent defines a common struct for proposal contents defined by external modules (i.e outside gov)
func (WeightedProposalContent) AppParamsKey ¶
func (w WeightedProposalContent) AppParamsKey() string
func (WeightedProposalContent) ContentSimulatorFn ¶
func (w WeightedProposalContent) ContentSimulatorFn() simulation.ContentSimulatorFn
func (WeightedProposalContent) DefaultWeight ¶
func (w WeightedProposalContent) DefaultWeight() int