chore: checkpoint 第一版

internal/deviceactivation/state.go

@@ -0,0 +1,162 @@
+package deviceactivation
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/jackc/pgx/v5"
+)
+
+type State string
+
+const (
+	Factory      State = "FACTORY"
+	Claimable    State = "CLAIMABLE"
+	Bound        State = "BOUND"
+	Provisioning State = "PROVISIONING"
+	Active       State = "ACTIVE"
+	Lost         State = "LOST"
+	Revoked      State = "REVOKED"
+)
+
+var (
+	ErrInvalidState       = errors.New("invalid device activation state")
+	ErrTransitionRejected = errors.New("device activation transition rejected")
+	ErrRevisionConflict   = errors.New("device activation revision conflict")
+	ErrDeviceNotFound     = errors.New("device activation target not found")
+)
+
+type Input struct {
+	DeviceID         string
+	TenantID         string
+	Target           State
+	Reason           string
+	Source           string
+	ActorType        string
+	ActorPublicID    *string
+	RequestID        string
+	ExpectedRevision *int64
+}
+
+type Result struct {
+	From          State
+	To            State
+	Revision      int64
+	DeviceVersion int64
+	UpdatedAt     time.Time
+	Changed       bool
+}
+
+func Parse(value string) (State, error) {
+	state := State(strings.ToUpper(strings.TrimSpace(value)))
+	switch state {
+	case Factory, Claimable, Bound, Provisioning, Active, Lost, Revoked:
+		return state, nil
+	default:
+		return "", ErrInvalidState
+	}
+}
+
+func AllowsDeviceAuthentication(state string) bool {
+	parsed, err := Parse(state)
+	if err != nil {
+		// Unit-test fakes and rolling deployments may omit the new field. Database
+		// rows are never empty after migration 50.
+		return strings.TrimSpace(state) == ""
+	}
+	return parsed == Claimable || parsed == Bound || parsed == Provisioning || parsed == Active
+}
+
+func CanTransition(from, to State) bool {
+	if from == to {
+		return true
+	}
+	if from == Revoked {
+		return false
+	}
+	if to == Revoked {
+		return true
+	}
+	switch from {
+	case Factory:
+		return to == Claimable
+	case Claimable:
+		return to == Bound
+	case Bound:
+		return to == Claimable || to == Provisioning
+	case Provisioning:
+		return to == Bound || to == Active
+	case Active:
+		return to == Claimable || to == Provisioning || to == Lost
+	case Lost:
+		return to == Claimable || to == Active
+	default:
+		return false
+	}
+}
+
+func Apply(ctx context.Context, tx pgx.Tx, input Input) (Result, error) {
+	if tx == nil || strings.TrimSpace(input.DeviceID) == "" || strings.TrimSpace(input.TenantID) == "" ||
+		strings.TrimSpace(input.Reason) == "" || strings.TrimSpace(input.Source) == "" || strings.TrimSpace(input.ActorType) == "" {
+		return Result{}, ErrInvalidState
+	}
+	target, err := Parse(string(input.Target))
+	if err != nil {
+		return Result{}, err
+	}
+	var currentText string
+	var revision, deviceVersion int64
+	var updatedAt time.Time
+	err = tx.QueryRow(ctx, `
+		SELECT activation_state,activation_revision,version,activation_updated_at
+		FROM device WHERE id=$1::uuid AND tenant_id=$2::uuid FOR UPDATE`, input.DeviceID, input.TenantID).
+		Scan(&currentText, &revision, &deviceVersion, &updatedAt)
+	if errors.Is(err, pgx.ErrNoRows) {
+		return Result{}, ErrDeviceNotFound
+	}
+	if err != nil {
+		return Result{}, fmt.Errorf("lock device activation: %w", err)
+	}
+	current, err := Parse(currentText)
+	if err != nil {
+		return Result{}, fmt.Errorf("parse stored device activation state: %w", err)
+	}
+	if input.ExpectedRevision != nil && revision != *input.ExpectedRevision {
+		return Result{}, ErrRevisionConflict
+	}
+	if !CanTransition(current, target) {
+		return Result{}, ErrTransitionRejected
+	}
+	if current == target {
+		return Result{From: current, To: target, Revision: revision, DeviceVersion: deviceVersion, UpdatedAt: updatedAt}, nil
+	}
+	err = tx.QueryRow(ctx, `
+		UPDATE device SET activation_state=$3,activation_revision=activation_revision+1,
+			activation_reason=$4,activation_updated_at=now(),version=version+1,updated_at=now()
+		WHERE id=$1::uuid AND tenant_id=$2::uuid
+		RETURNING activation_revision,version,activation_updated_at`, input.DeviceID, input.TenantID, target, strings.TrimSpace(input.Reason)).
+		Scan(&revision, &deviceVersion, &updatedAt)
+	if err != nil {
+		return Result{}, fmt.Errorf("update device activation: %w", err)
+	}
+	_, err = tx.Exec(ctx, `
+		INSERT INTO device_activation_transition(
+			tenant_id,device_id,from_state,to_state,reason,source,actor_type,actor_public_id,request_id,activation_revision
+		) VALUES($1::uuid,$2::uuid,$3,$4,$5,$6,$7,NULLIF($8,'')::uuid,NULLIF($9,''),$10)`,
+		input.TenantID, input.DeviceID, current, target, strings.TrimSpace(input.Reason), strings.TrimSpace(input.Source),
+		strings.TrimSpace(input.ActorType), optionalString(input.ActorPublicID), strings.TrimSpace(input.RequestID), revision)
+	if err != nil {
+		return Result{}, fmt.Errorf("record device activation transition: %w", err)
+	}
+	return Result{From: current, To: target, Revision: revision, DeviceVersion: deviceVersion, UpdatedAt: updatedAt, Changed: true}, nil
+}
+
+func optionalString(value *string) string {
+	if value == nil {
+		return ""
+	}
+	return strings.TrimSpace(*value)
+}