Merge pull request #72 from makasim/split-state-commands

split flowstate.GetCommand into flowstate.GetStateByID and flowstate.GetStateByLabels.

Author: makasim

cmd_get.go

@@ -0,0 +1,61 @@
+package flowstate
+
+import "fmt"
+
+func GetStateByID(stateCtx *StateCtx, id StateID, rev int64) *GetStateByIDCommand {
+	return &GetStateByIDCommand{
+		ID:       id,
+		Rev:      rev,
+		StateCtx: stateCtx,
+	}
+}
+
+type GetStateByIDCommand struct {
+	command
+
+	ID  StateID
+	Rev int64
+
+	StateCtx *StateCtx
+}
+
+func (cmd *GetStateByIDCommand) Prepare() error {
+	if cmd.ID == "" {
+		return fmt.Errorf(`id is empty`)
+	}
+	if cmd.Rev < 0 {
+		return fmt.Errorf(`rev must be >= 0`)
+	}
+	return nil
+}
+
+func (cmd *GetStateByIDCommand) Result() (*StateCtx, error) {
+	if cmd.StateCtx == nil {
+		return nil, fmt.Errorf(`cmd.StateCtx`)
+	}
+
+	return cmd.StateCtx, nil
+}
+
+func GetStateByLabels(stateCtx *StateCtx, labels map[string]string) *GetStateByLabelsCommand {
+	return &GetStateByLabelsCommand{
+		Labels:   labels,
+		StateCtx: stateCtx,
+	}
+}
+
+type GetStateByLabelsCommand struct {
+	command
+
+	Labels map[string]string
+
+	StateCtx *StateCtx
+}
+
+func (cmd *GetStateByLabelsCommand) Result() (*StateCtx, error) {
+	if cmd.StateCtx == nil {
+		return nil, fmt.Errorf(`cmd.StateCtx is nil`)
+	}
+
+	return cmd.StateCtx, nil
+}

cmd_get_many.go

@@ -0,0 +1,76 @@
+package flowstate
+
+import (
+	"fmt"
+	"time"
+)
+
+const GetManyDefaultLimit = 50
+
+type GetStatesResult struct {
+	States []State
+	More   bool
+}
+
+func GetStatesByLabels(labels map[string]string) *GetStatesCommand {
+	return (&GetStatesCommand{}).WithORLabels(labels)
+}
+
+type GetStatesCommand struct {
+	command
+
+	SinceRev   int64
+	SinceTime  time.Time
+	Labels     []map[string]string
+	LatestOnly bool
+	Limit      int
+
+	result *GetStatesResult
+}
+
+func (cmd *GetStatesCommand) Result() (*GetStatesResult, error) {
+	if cmd.result == nil {
+		return nil, fmt.Errorf("no result set")
+	}
+
+	return cmd.result, nil
+}
+
+func (cmd *GetStatesCommand) SetResult(result *GetStatesResult) {
+	cmd.result = result
+}
+
+func (cmd *GetStatesCommand) WithSinceRev(rev int64) *GetStatesCommand {
+	cmd.SinceRev = rev
+	return cmd
+}
+
+func (cmd *GetStatesCommand) WithLatestOnly() *GetStatesCommand {
+	cmd.LatestOnly = true
+	return cmd
+}
+
+func (cmd *GetStatesCommand) WithSinceLatest() *GetStatesCommand {
+	cmd.SinceRev = -1
+	return cmd
+}
+
+func (cmd *GetStatesCommand) WithSinceTime(since time.Time) *GetStatesCommand {
+	cmd.SinceTime = since
+	return cmd
+}
+
+func (cmd *GetStatesCommand) WithORLabels(labels map[string]string) *GetStatesCommand {
+	if len(labels) == 0 {
+		return cmd
+	}
+
+	cmd.Labels = append(cmd.Labels, labels)
+	return cmd
+}
+
+func (cmd *GetStatesCommand) Prepare() {
+	if cmd.Limit == 0 {
+		cmd.Limit = GetManyDefaultLimit
+	}
+}

cmd_get_state.go

@@ -125,7 +125,7 @@ func logDo(execSessID int64, cmd0 Command, l *slog.Logger) {
 		args = append(args, "cmd", "serialize")
 	case *GetFlowCommand:
 		args = append(args, "cmd", "get_flow", "flow_id", cmd.StateCtx.Current.Transition.ToID)
-	case *GetManyCommand:
+	case *GetStatesCommand:
 		args = append(args, "cmd", "watch")
 		if cmd.SinceRev > 0 {
 			args = append(args, "since_rev", cmd.SinceRev)

cmd_get_states.go

@@ -21,42 +21,51 @@ func NewGetter(l *Log) *Getter {
 
 func (d *Getter) Do(cmd0 flowstate.Command) error {
 	switch cmd := cmd0.(type) {
-	case *flowstate.GetCommand:
-		return d.doGet(cmd)
-	case *flowstate.GetManyCommand:
+	case *flowstate.GetStateByIDCommand:
+		return d.doGetStateByID(cmd)
+	case *flowstate.GetStateByLabelsCommand:
+		return d.doGetStateByLabels(cmd)
+	case *flowstate.GetStatesCommand:
 		return d.doGetMany(cmd)
 	default:
 		return flowstate.ErrCommandNotSupported
 	}
 }
 
-func (d *Getter) doGet(cmd *flowstate.GetCommand) error {
-	if len(cmd.Labels) > 0 {
-		stateCtx, _ := d.l.GetLatestByLabels([]map[string]string{cmd.Labels})
-		if stateCtx == nil {
-			return fmt.Errorf("%w; labels=%v", flowstate.ErrNotFound, cmd.Labels)
-		}
-		stateCtx.CopyTo(cmd.StateCtx)
-	} else if cmd.ID != "" && cmd.Rev == 0 {
+func (d *Getter) doGetStateByID(cmd *flowstate.GetStateByIDCommand) error {
+	if err := cmd.Prepare(); err != nil {
+		return fmt.Errorf("get state by id: %w", err)
+	}
+
+	if cmd.Rev == 0 {
 		stateCtx, _ := d.l.GetLatestByID(cmd.ID)
 		if stateCtx == nil {
 			return fmt.Errorf("%w; id=%s", flowstate.ErrNotFound, cmd.ID)
 		}
 		stateCtx.CopyTo(cmd.StateCtx)
-	} else if cmd.ID != "" && cmd.Rev > 0 {
-		stateCtx := d.l.GetByIDAndRev(cmd.ID, cmd.Rev)
-		if stateCtx == nil {
-			return fmt.Errorf("%w; id=%s rev=%d", flowstate.ErrNotFound, cmd.ID, cmd.Rev)
-		}
-		stateCtx.CopyTo(cmd.StateCtx)
-	} else {
-		return fmt.Errorf("invalid get command")
+		return nil
+	}
+
+	stateCtx := d.l.GetByIDAndRev(cmd.ID, cmd.Rev)
+	if stateCtx == nil {
+		return fmt.Errorf("%w; id=%s rev=%d", flowstate.ErrNotFound, cmd.ID, cmd.Rev)
+	}
+	stateCtx.CopyTo(cmd.StateCtx)
+
+	return nil
+}
+
+func (d *Getter) doGetStateByLabels(cmd *flowstate.GetStateByLabelsCommand) error {
+	stateCtx, _ := d.l.GetLatestByLabels([]map[string]string{cmd.Labels})
+	if stateCtx == nil {
+		return fmt.Errorf("%w; labels=%v", flowstate.ErrNotFound, cmd.Labels)
 	}
+	stateCtx.CopyTo(cmd.StateCtx)
 
 	return nil
 }
 
-func (d *Getter) doGetMany(cmd *flowstate.GetManyCommand) error {
+func (d *Getter) doGetMany(cmd *flowstate.GetStatesCommand) error {
 	cmd.Prepare()
 
 	states := make([]flowstate.State, 0, cmd.Limit)
@@ -85,7 +94,7 @@ func (d *Getter) doGetMany(cmd *flowstate.GetManyCommand) error {
 		d.l.Unlock()
 
 		if len(logStates) == 0 {
-			cmd.SetResult(&flowstate.GetManyResult{
+			cmd.SetResult(&flowstate.GetStatesResult{
 				States: states,
 			})
 			return nil
@@ -106,14 +115,14 @@ func (d *Getter) doGetMany(cmd *flowstate.GetManyCommand) error {
 		}
 
 		if len(states) >= cmd.Limit {
-			cmd.SetResult(&flowstate.GetManyResult{
+			cmd.SetResult(&flowstate.GetStatesResult{
 				States: states[:cmd.Limit],
 				More:   len(states) > cmd.Limit,
 			})
 
 			return nil
 		} else if sinceRev >= untilRev {
-			cmd.SetResult(&flowstate.GetManyResult{
+			cmd.SetResult(&flowstate.GetStatesResult{
 				States: states,
 				More:   false,
 			})