dkron的fsm是怎样的

今天就跟大家聊聊有关dkron的fsm是怎样的，可能很多人都不太了解，为了让大家更加了解，小编给大家总结了以下内容，希望大家根据这篇文章可以有所收获。

MessageType

// MessageType is the type to encode FSM commands.type MessageType uint8const (        // SetJobType is the command used to store a job in the store.        SetJobType MessageType = iota        // DeleteJobType is the command used to delete a Job from the store.        DeleteJobType        // SetExecutionType is the command used to store an Execution to the store.        SetExecutionType        // DeleteExecutionsType is the command used to delete executions from the store.        DeleteExecutionsType        // ExecutionDoneType is the command to perform the logic needed once an exeuction        // is done.        ExecutionDoneType)

MessageType可以分为SetJobType、DeleteJobType、SetExecutionType、DeleteExecutionsType、ExecutionDoneType

dkronFSM

type dkronFSM struct {        store Storage        // proAppliers holds the set of pro only LogAppliers        proAppliers LogAppliers}// NewFSM is used to construct a new FSM with a blank statefunc newFSM(store Storage, logAppliers LogAppliers) *dkronFSM {        return &dkronFSM{                store:       store,                proAppliers: logAppliers,        }}// Apply applies a Raft log entry to the key-value store.func (d *dkronFSM) Apply(l *raft.Log) interface{} {        buf := l.Data        msgType := MessageType(buf[0])        log.WithField("command", msgType).Debug("fsm: received command")        switch msgType {        case SetJobType:                return d.applySetJob(buf[1:])        case DeleteJobType:                return d.applyDeleteJob(buf[1:])        case ExecutionDoneType:                return d.applyExecutionDone(buf[1:])        case SetExecutionType:                return d.applySetExecution(buf[1:])        }        // Check enterprise only message types.        if applier, ok := d.proAppliers[msgType]; ok {                return applier(buf[1:], l.Index)        }        return nil}func (d *dkronFSM) applySetJob(buf []byte) interface{} {        var pj dkronpb.Job        if err := proto.Unmarshal(buf, &pj); err != nil {                return err        }        job := NewJobFromProto(&pj)        if err := d.store.SetJob(job, false); err != nil {                return err        }        return nil}func (d *dkronFSM) applyDeleteJob(buf []byte) interface{} {        var djr dkronpb.DeleteJobRequest        if err := proto.Unmarshal(buf, &djr); err != nil {                return err        }        job, err := d.store.DeleteJob(djr.GetJobName())        if err != nil {                return err        }        return job}func (d *dkronFSM) applyExecutionDone(buf []byte) interface{} {        var execDoneReq dkronpb.ExecutionDoneRequest        if err := proto.Unmarshal(buf, &execDoneReq); err != nil {                return err        }        execution := NewExecutionFromProto(execDoneReq.Execution)        log.WithField("execution", execution.Key()).                WithField("output", string(execution.Output)).                Debug("fsm: Setting execution")        _, err := d.store.SetExecutionDone(execution)        return err}func (d *dkronFSM) applySetExecution(buf []byte) interface{} {        var pbex dkronpb.Execution        if err := proto.Unmarshal(buf, &pbex); err != nil {                return err        }        execution := NewExecutionFromProto(&pbex)        key, err := d.store.SetExecution(execution)        if err != nil {                return err        }        return key}// Snapshot returns a snapshot of the key-value store. We wrap// the things we need in dkronSnapshot and then send that over to Persist.// Persist encodes the needed data from dkronSnapshot and transport it to// Restore where the necessary data is replicated into the finite state machine.// This allows the consensus algorithm to truncate the replicated log.func (d *dkronFSM) Snapshot() (raft.FSMSnapshot, error) {        return &dkronSnapshot{store: d.store}, nil}// Restore stores the key-value store to a previous state.func (d *dkronFSM) Restore(r io.ReadCloser) error {        defer r.Close()        return d.store.Restore(r)}// LogApplier is the definition of a function that can apply a Raft logtype LogApplier func(buf []byte, index uint64) interface{}

dkronFSM定义了store、proAppliers属性；Apply方法将raft的log保存到KV存储中，具体分不同msgType做不同处理；最后根据msgType查找LogAppliers

小结

dkron的FSM根据不同msgType做不同处理，具体有applySetJob、applyDeleteJob、applyExecutionDone、applySetExecution方法。

看完上述内容，你们对dkron的fsm是怎样的有进一步的了解吗？如果还想了解更多知识或者相关内容，请关注行业资讯频道，感谢大家的支持。