organize essential APIs into platform, workflow and pkg folders (#337)

Add more logic to the way code is organized.

	/pkg -- library code not directly connected to micromdm
	/mdm -- packages meant for the services devices interract with. The MDM protocol.
	/dep -- DEP API and related packages.
	/platform -- Core APIs the server provides. Commands API, Devices API, queue, pubsub etc.
	/workflow -- Packages/API that build on top of platform. Today that's the webhook package.
		     Depending on what ends up here, the workflow folder might become its own repository.

platform/queue/command_queued.go

@@ -0,0 +1,34 @@
+package queue
+
+import (
+	"errors"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/micromdm/micromdm/platform/queue/internal/commandqueuedproto"
+)
+
+type QueueCommandQueued struct {
+	DeviceUDID  string
+	CommandUUID string
+}
+
+func MarshalQueuedCommand(cq *QueueCommandQueued) ([]byte, error) {
+	if cq == nil {
+		return nil, errors.New("marshalling nil QueueCommandQueued")
+	}
+	return proto.Marshal(&commandqueued.CommandQueued{
+		DeviceUdid:  cq.DeviceUDID,
+		CommandUuid: cq.DeviceUDID,
+	})
+}
+
+func UnmarshalQueuedCommand(data []byte) (*QueueCommandQueued, error) {
+	cmdQueued := commandqueued.CommandQueued{}
+	if err := proto.Unmarshal(data, &cmdQueued); err != nil {
+		return nil, err
+	}
+	queueCmdQueued := new(QueueCommandQueued)
+	queueCmdQueued.DeviceUDID = cmdQueued.DeviceUdid
+	queueCmdQueued.CommandUUID = cmdQueued.CommandUuid
+	return queueCmdQueued, nil
+}

platform/queue/device_command.go

@@ -0,0 +1,174 @@
+package queue
+
+import (
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/pkg/errors"
+
+	"github.com/micromdm/micromdm/platform/queue/internal/devicecommandproto"
+)
+
+type Command struct {
+	UUID    string
+	Payload []byte
+
+	CreatedAt    time.Time
+	LastSentAt   time.Time
+	Acknowledged time.Time
+
+	TimesSent int
+
+	LastStatus     string
+	FailureMessage []byte
+}
+
+type DeviceCommand struct {
+	DeviceUDID string
+	Commands   []Command
+
+	// These are going to scale great. We'll have to see.
+	Completed []Command
+	Failed    []Command
+	NotNow    []Command
+}
+
+func MarshalDeviceCommand(c *DeviceCommand) ([]byte, error) {
+	protoc := devicecommandproto.DeviceCommand{
+		DeviceUdid: c.DeviceUDID,
+	}
+
+	// TODO add helper here to reduce copy/pasted boilerplate.
+	for _, command := range c.Commands {
+		protoc.Commands = append(protoc.Commands, &devicecommandproto.Command{
+			Uuid:         command.UUID,
+			Payload:      command.Payload,
+			CreatedAt:    command.CreatedAt.UnixNano(),
+			LastSentAt:   command.LastSentAt.UnixNano(),
+			Acknowledged: command.Acknowledged.UnixNano(),
+
+			TimesSent: int64(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range c.Completed {
+		protoc.Completed = append(protoc.Completed, &devicecommandproto.Command{
+			Uuid:         command.UUID,
+			Payload:      command.Payload,
+			CreatedAt:    command.CreatedAt.UnixNano(),
+			LastSentAt:   command.LastSentAt.UnixNano(),
+			Acknowledged: command.Acknowledged.UnixNano(),
+
+			TimesSent: int64(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range c.Failed {
+		protoc.Failed = append(protoc.Failed, &devicecommandproto.Command{
+			Uuid:         command.UUID,
+			Payload:      command.Payload,
+			CreatedAt:    command.CreatedAt.UnixNano(),
+			LastSentAt:   command.LastSentAt.UnixNano(),
+			Acknowledged: command.Acknowledged.UnixNano(),
+
+			TimesSent: int64(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range c.NotNow {
+		protoc.NotNow = append(protoc.NotNow, &devicecommandproto.Command{
+			Uuid:         command.UUID,
+			Payload:      command.Payload,
+			CreatedAt:    command.CreatedAt.UnixNano(),
+			LastSentAt:   command.LastSentAt.UnixNano(),
+			Acknowledged: command.Acknowledged.UnixNano(),
+
+			TimesSent: int64(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+	return proto.Marshal(&protoc)
+}
+
+func UnmarshalDeviceCommand(data []byte, c *DeviceCommand) error {
+	var pb devicecommandproto.DeviceCommand
+	if err := proto.Unmarshal(data, &pb); err != nil {
+		return errors.Wrap(err, "unmarshal proto to DeviceCommand")
+	}
+	c.DeviceUDID = pb.GetDeviceUdid()
+	protoCommands := pb.GetCommands()
+	protoCommandsCompleted := pb.GetCompleted()
+	protoCommandsFailed := pb.GetFailed()
+	protoCommandsNotNow := pb.GetNotNow()
+	for _, command := range protoCommands {
+		c.Commands = append(c.Commands, Command{
+			UUID:         command.GetUuid(),
+			Payload:      command.GetPayload(),
+			CreatedAt:    time.Unix(0, command.GetCreatedAt()).UTC(),
+			LastSentAt:   time.Unix(0, command.GetLastSentAt()).UTC(),
+			Acknowledged: time.Unix(0, command.GetAcknowledged()).UTC(),
+
+			TimesSent: int(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range protoCommandsCompleted {
+		c.Completed = append(c.Completed, Command{
+			UUID:         command.GetUuid(),
+			Payload:      command.GetPayload(),
+			CreatedAt:    time.Unix(0, command.GetCreatedAt()).UTC(),
+			LastSentAt:   time.Unix(0, command.GetLastSentAt()).UTC(),
+			Acknowledged: time.Unix(0, command.GetAcknowledged()).UTC(),
+
+			TimesSent: int(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range protoCommandsFailed {
+		c.Failed = append(c.Failed, Command{
+			UUID:         command.GetUuid(),
+			Payload:      command.GetPayload(),
+			CreatedAt:    time.Unix(0, command.GetCreatedAt()).UTC(),
+			LastSentAt:   time.Unix(0, command.GetLastSentAt()).UTC(),
+			Acknowledged: time.Unix(0, command.GetAcknowledged()).UTC(),
+
+			TimesSent: int(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+
+	for _, command := range protoCommandsNotNow {
+		c.NotNow = append(c.NotNow, Command{
+			UUID:         command.GetUuid(),
+			Payload:      command.GetPayload(),
+			CreatedAt:    time.Unix(0, command.GetCreatedAt()).UTC(),
+			LastSentAt:   time.Unix(0, command.GetLastSentAt()).UTC(),
+			Acknowledged: time.Unix(0, command.GetAcknowledged()).UTC(),
+
+			TimesSent: int(command.TimesSent),
+
+			LastStatus:     command.LastStatus,
+			FailureMessage: command.FailureMessage,
+		})
+	}
+	return nil
+}

platform/queue/internal/commandqueuedproto/command_queued.pb.go

@@ -0,0 +1,71 @@
+// Code generated by protoc-gen-go.
+// source: command_queued.proto
+// DO NOT EDIT!
+
+/*
+Package commandqueued is a generated protocol buffer package.
+
+It is generated from these files:
+	command_queued.proto
+
+It has these top-level messages:
+	CommandQueued
+*/
+package commandqueued
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+type CommandQueued struct {
+	DeviceUdid  string `protobuf:"bytes,1,opt,name=device_udid,json=deviceUdid" json:"device_udid,omitempty"`
+	CommandUuid string `protobuf:"bytes,2,opt,name=command_uuid,json=commandUuid" json:"command_uuid,omitempty"`
+}
+
+func (m *CommandQueued) Reset()                    { *m = CommandQueued{} }
+func (m *CommandQueued) String() string            { return proto.CompactTextString(m) }
+func (*CommandQueued) ProtoMessage()               {}
+func (*CommandQueued) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *CommandQueued) GetDeviceUdid() string {
+	if m != nil {
+		return m.DeviceUdid
+	}
+	return ""
+}
+
+func (m *CommandQueued) GetCommandUuid() string {
+	if m != nil {
+		return m.CommandUuid
+	}
+	return ""
+}
+
+func init() {
+	proto.RegisterType((*CommandQueued)(nil), "commandqueued.CommandQueued")
+}
+
+func init() { proto.RegisterFile("command_queued.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 117 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x12, 0x49, 0xce, 0xcf, 0xcd,
+	0x4d, 0xcc, 0x4b, 0x89, 0x2f, 0x2c, 0x4d, 0x2d, 0x4d, 0x4d, 0xd1, 0x2b, 0x28, 0xca, 0x2f, 0xc9,
+	0x17, 0xe2, 0x85, 0x8a, 0x42, 0x04, 0x95, 0x82, 0xb9, 0x78, 0x9d, 0x21, 0x02, 0x81, 0x60, 0x01,
+	0x21, 0x79, 0x2e, 0xee, 0x94, 0xd4, 0xb2, 0xcc, 0xe4, 0xd4, 0xf8, 0xd2, 0x94, 0xcc, 0x14, 0x09,
+	0x46, 0x05, 0x46, 0x0d, 0xce, 0x20, 0x2e, 0x88, 0x50, 0x68, 0x4a, 0x66, 0x8a, 0x90, 0x22, 0x17,
+	0x0f, 0xcc, 0xe0, 0xd2, 0xd2, 0xcc, 0x14, 0x09, 0x26, 0xb0, 0x0a, 0x6e, 0xa8, 0x58, 0x68, 0x69,
+	0x66, 0x4a, 0x12, 0x1b, 0xd8, 0x2a, 0x63, 0x40, 0x00, 0x00, 0x00, 0xff, 0xff, 0x6e, 0x34, 0x2e,
+	0x49, 0x82, 0x00, 0x00, 0x00,
+}

platform/queue/internal/commandqueuedproto/command_queued.proto

@@ -0,0 +1,8 @@
+syntax = "proto3";
+
+package commandqueued;
+
+message CommandQueued {
+    string device_udid = 1;
+    string command_uuid = 2;
+}

platform/queue/internal/devicecommandproto/device_command.go

@@ -0,0 +1,3 @@
+package devicecommandproto
+
+//go:generate protoc --go_out=. device_command.proto

platform/queue/internal/devicecommandproto/device_command.pb.go

@@ -0,0 +1,181 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: device_command.proto
+
+/*
+Package devicecommandproto is a generated protocol buffer package.
+
+It is generated from these files:
+	device_command.proto
+
+It has these top-level messages:
+	Command
+	DeviceCommand
+*/
+package devicecommandproto
+
+import proto "github.com/golang/protobuf/proto"
+import fmt "fmt"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = fmt.Errorf
+var _ = math.Inf
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the proto package it is being compiled against.
+// A compilation error at this line likely means your copy of the
+// proto package needs to be updated.
+const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
+
+type Command struct {
+	Uuid           string `protobuf:"bytes,1,opt,name=uuid" json:"uuid,omitempty"`
+	Payload        []byte `protobuf:"bytes,2,opt,name=payload,proto3" json:"payload,omitempty"`
+	CreatedAt      int64  `protobuf:"varint,3,opt,name=created_at,json=createdAt" json:"created_at,omitempty"`
+	LastSentAt     int64  `protobuf:"varint,4,opt,name=last_sent_at,json=lastSentAt" json:"last_sent_at,omitempty"`
+	Acknowledged   int64  `protobuf:"varint,5,opt,name=acknowledged" json:"acknowledged,omitempty"`
+	TimesSent      int64  `protobuf:"varint,6,opt,name=times_sent,json=timesSent" json:"times_sent,omitempty"`
+	LastStatus     string `protobuf:"bytes,7,opt,name=last_status,json=lastStatus" json:"last_status,omitempty"`
+	FailureMessage []byte `protobuf:"bytes,8,opt,name=failure_message,json=failureMessage,proto3" json:"failure_message,omitempty"`
+}
+
+func (m *Command) Reset()                    { *m = Command{} }
+func (m *Command) String() string            { return proto.CompactTextString(m) }
+func (*Command) ProtoMessage()               {}
+func (*Command) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+func (m *Command) GetUuid() string {
+	if m != nil {
+		return m.Uuid
+	}
+	return ""
+}
+
+func (m *Command) GetPayload() []byte {
+	if m != nil {
+		return m.Payload
+	}
+	return nil
+}
+
+func (m *Command) GetCreatedAt() int64 {
+	if m != nil {
+		return m.CreatedAt
+	}
+	return 0
+}
+
+func (m *Command) GetLastSentAt() int64 {
+	if m != nil {
+		return m.LastSentAt
+	}
+	return 0
+}
+
+func (m *Command) GetAcknowledged() int64 {
+	if m != nil {
+		return m.Acknowledged
+	}
+	return 0
+}
+
+func (m *Command) GetTimesSent() int64 {
+	if m != nil {
+		return m.TimesSent
+	}
+	return 0
+}
+
+func (m *Command) GetLastStatus() string {
+	if m != nil {
+		return m.LastStatus
+	}
+	return ""
+}
+
+func (m *Command) GetFailureMessage() []byte {
+	if m != nil {
+		return m.FailureMessage
+	}
+	return nil
+}
+
+type DeviceCommand struct {
+	DeviceUdid string     `protobuf:"bytes,1,opt,name=device_udid,json=deviceUdid" json:"device_udid,omitempty"`
+	Commands   []*Command `protobuf:"bytes,2,rep,name=commands" json:"commands,omitempty"`
+	Completed  []*Command `protobuf:"bytes,3,rep,name=completed" json:"completed,omitempty"`
+	Failed     []*Command `protobuf:"bytes,4,rep,name=failed" json:"failed,omitempty"`
+	NotNow     []*Command `protobuf:"bytes,5,rep,name=not_now,json=notNow" json:"not_now,omitempty"`
+}
+
+func (m *DeviceCommand) Reset()                    { *m = DeviceCommand{} }
+func (m *DeviceCommand) String() string            { return proto.CompactTextString(m) }
+func (*DeviceCommand) ProtoMessage()               {}
+func (*DeviceCommand) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func (m *DeviceCommand) GetDeviceUdid() string {
+	if m != nil {
+		return m.DeviceUdid
+	}
+	return ""
+}
+
+func (m *DeviceCommand) GetCommands() []*Command {
+	if m != nil {
+		return m.Commands
+	}
+	return nil
+}
+
+func (m *DeviceCommand) GetCompleted() []*Command {
+	if m != nil {
+		return m.Completed
+	}
+	return nil
+}
+
+func (m *DeviceCommand) GetFailed() []*Command {
+	if m != nil {
+		return m.Failed
+	}
+	return nil
+}
+
+func (m *DeviceCommand) GetNotNow() []*Command {
+	if m != nil {
+		return m.NotNow
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterType((*Command)(nil), "devicecommandproto.Command")
+	proto.RegisterType((*DeviceCommand)(nil), "devicecommandproto.DeviceCommand")
+}
+
+func init() { proto.RegisterFile("device_command.proto", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 324 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x90, 0x41, 0x4b, 0xeb, 0x40,
+	0x10, 0xc7, 0x49, 0xd2, 0x36, 0xed, 0xb4, 0xef, 0x3d, 0x18, 0xde, 0x61, 0xe1, 0xf1, 0x68, 0xe8,
+	0xc5, 0x9c, 0x7a, 0xb0, 0x82, 0x78, 0x2c, 0x7a, 0xd5, 0x43, 0xc4, 0x73, 0x58, 0xb3, 0x63, 0x09,
+	0x26, 0xbb, 0xa5, 0x3b, 0xb1, 0xf8, 0x01, 0x3c, 0xfb, 0x95, 0x25, 0xbb, 0xdb, 0x8a, 0x78, 0xa8,
+	0xb7, 0xe4, 0xc7, 0x7f, 0xe6, 0x3f, 0xfb, 0x83, 0xbf, 0x8a, 0x5e, 0xea, 0x8a, 0xca, 0xca, 0xb4,
+	0xad, 0xd4, 0x6a, 0xb9, 0xdd, 0x19, 0x36, 0x88, 0x9e, 0x06, 0xe8, 0xd8, 0xe2, 0x2d, 0x86, 0xf4,
+	0xda, 0x03, 0x44, 0x18, 0x74, 0x5d, 0xad, 0x44, 0x94, 0x45, 0xf9, 0xa4, 0x70, 0xdf, 0x28, 0x20,
+	0xdd, 0xca, 0xd7, 0xc6, 0x48, 0x25, 0xe2, 0x2c, 0xca, 0x67, 0xc5, 0xe1, 0x17, 0xff, 0x03, 0x54,
+	0x3b, 0x92, 0x4c, 0xaa, 0x94, 0x2c, 0x92, 0x2c, 0xca, 0x93, 0x62, 0x12, 0xc8, 0x9a, 0x31, 0x83,
+	0x59, 0x23, 0x2d, 0x97, 0x96, 0x34, 0xf7, 0x81, 0x81, 0x0b, 0x40, 0xcf, 0xee, 0x49, 0xf3, 0x9a,
+	0x71, 0x01, 0x33, 0x59, 0x3d, 0x6b, 0xb3, 0x6f, 0x48, 0x6d, 0x48, 0x89, 0xa1, 0x4b, 0x7c, 0x61,
+	0x7d, 0x09, 0xd7, 0x2d, 0x59, 0xb7, 0x46, 0x8c, 0x7c, 0x89, 0x23, 0xfd, 0x12, 0x9c, 0xc3, 0xd4,
+	0x97, 0xb0, 0xe4, 0xce, 0x8a, 0xd4, 0x1d, 0xee, 0x3b, 0x1c, 0xc1, 0x33, 0xf8, 0xf3, 0x24, 0xeb,
+	0xa6, 0xdb, 0x51, 0xd9, 0x92, 0xb5, 0x72, 0x43, 0x62, 0xec, 0x9e, 0xf1, 0x3b, 0xe0, 0x5b, 0x4f,
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+	0x02, 0x1e, 0x3d, 0xa8, 0x5a, 0xe1, 0x25, 0x8c, 0x83, 0x4a, 0x2b, 0xe2, 0x2c, 0xc9, 0xa7, 0xe7,
+	0xff, 0x96, 0xdf, 0x0d, 0x2f, 0xc3, 0xbe, 0xe2, 0x18, 0xc6, 0x2b, 0x98, 0x54, 0xa6, 0xdd, 0x36,
+	0xc4, 0xa4, 0x44, 0x72, 0x7a, 0xf2, 0x33, 0x8d, 0x2b, 0x18, 0xf5, 0x87, 0x93, 0x12, 0x83, 0xd3,
+	0x73, 0x21, 0x8a, 0x17, 0x90, 0x6a, 0xc3, 0xa5, 0x36, 0x7b, 0x31, 0xfc, 0xc1, 0x94, 0x36, 0x7c,
+	0x67, 0xf6, 0x8f, 0x23, 0x87, 0x57, 0x1f, 0x01, 0x00, 0x00, 0xff, 0xff, 0x83, 0x8d, 0x73, 0x78,
+	0x4c, 0x02, 0x00, 0x00,
+}

platform/queue/internal/devicecommandproto/device_command.proto

@@ -0,0 +1,25 @@
+syntax = "proto3";
+
+package devicecommandproto;
+
+message Command {
+    string uuid = 1;
+    bytes payload = 2;
+
+    int64 created_at = 3;
+    int64 last_sent_at = 4;
+    int64 acknowledged = 5;
+
+    int64 times_sent = 6;
+
+    string last_status = 7;
+    bytes failure_message = 8;
+}
+
+message DeviceCommand {
+    string device_udid = 1;
+    repeated Command commands = 2;
+    repeated Command completed = 3;
+    repeated Command failed = 4;
+    repeated Command not_now = 5;
+}

platform/queue/queue.go

@@ -0,0 +1,246 @@
+// Package queue implements a boldDB backed queue for MDM Commands.
+package queue
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/boltdb/bolt"
+	"github.com/groob/plist"
+	"github.com/pkg/errors"
+
+	"github.com/micromdm/mdm"
+	"github.com/micromdm/micromdm/platform/command"
+	"github.com/micromdm/micromdm/platform/pubsub"
+)
+
+const (
+	DeviceCommandBucket = "mdm.DeviceCommands"
+
+	CommandQueuedTopic = "mdm.CommandQueued"
+)
+
+type Store struct {
+	*bolt.DB
+}
+
+func (db *Store) Next(ctx context.Context, resp mdm.Response) (*Command, error) {
+	udid := resp.UDID
+	if resp.UserID != nil {
+		// use the user id for user level commands
+		udid = *resp.UserID
+	}
+	dc, err := db.DeviceCommand(udid)
+	if err != nil {
+		if isNotFound(err) {
+			return nil, nil
+		}
+		return nil, errors.Wrapf(err, "get device command from queue, udid: %s", resp.UDID)
+	}
+
+	var cmd *Command
+	switch resp.Status {
+	case "NotNow":
+		// We will try this command later when the device is not
+		// responding with NotNow
+		x, a := cut(dc.Commands, resp.CommandUUID)
+		dc.Commands = a
+		if x == nil {
+			break
+		}
+		dc.NotNow = append(dc.NotNow, *x)
+
+	case "Acknowledged":
+		// move to completed, send next
+		x, a := cut(dc.Commands, resp.CommandUUID)
+		dc.Commands = a
+		if x == nil {
+			break
+		}
+		dc.Completed = append(dc.Completed, *x)
+	case "Error":
+		// move to failed, send next
+		x, a := cut(dc.Commands, resp.CommandUUID)
+		dc.Commands = a
+		if x == nil { // must've already bin ackd
+			break
+		}
+		dc.Failed = append(dc.Failed, *x)
+
+	case "CommandFormatError":
+		// move to failed
+		x, a := cut(dc.Commands, resp.CommandUUID)
+		dc.Commands = a
+		if x == nil {
+			break
+		}
+		dc.Failed = append(dc.Failed, *x)
+
+	case "Idle":
+		// will send next command below
+
+	default:
+		return nil, fmt.Errorf("unknown response status: %s", resp.Status)
+	}
+
+	// pop the first command from the queue and add it to the end.
+	// If the regular queue is empty, send a command that got
+	// refused with NotNow before.
+	cmd, dc.Commands = popFirst(dc.Commands)
+	if cmd != nil {
+		dc.Commands = append(dc.Commands, *cmd)
+	} else if resp.Status != "NotNow" {
+		cmd, dc.NotNow = popFirst(dc.NotNow)
+		if cmd != nil {
+			dc.Commands = append(dc.Commands, *cmd)
+		}
+	}
+
+	if err := db.Save(dc); err != nil {
+		return nil, err
+	}
+
+	return cmd, nil
+}
+
+func popFirst(all []Command) (*Command, []Command) {
+	if len(all) == 0 {
+		return nil, all
+	}
+	first := all[0]
+	all = append(all[:0], all[1:]...)
+	return &first, all
+}
+
+func cut(all []Command, uuid string) (*Command, []Command) {
+	for i, cmd := range all {
+		if cmd.UUID == uuid {
+			all = append(all[:i], all[i+1:]...)
+			return &cmd, all
+		}
+	}
+	return nil, all
+}
+
+func NewQueue(db *bolt.DB, pubsub pubsub.PublishSubscriber) (*Store, error) {
+	err := db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucketIfNotExists([]byte(DeviceCommandBucket))
+		return err
+	})
+	if err != nil {
+		return nil, errors.Wrapf(err, "creating %s bucket", DeviceCommandBucket)
+	}
+	datastore := &Store{DB: db}
+	if err := datastore.pollCommands(pubsub); err != nil {
+		return nil, err
+	}
+	return datastore, nil
+}
+
+func (db *Store) Save(cmd *DeviceCommand) error {
+	tx, err := db.DB.Begin(true)
+	if err != nil {
+		return errors.Wrap(err, "begin transaction")
+	}
+	bkt := tx.Bucket([]byte(DeviceCommandBucket))
+	if bkt == nil {
+		return fmt.Errorf("bucket %q not found!", DeviceCommandBucket)
+	}
+	devproto, err := MarshalDeviceCommand(cmd)
+	if err != nil {
+		return errors.Wrap(err, "marshalling DeviceCommand")
+	}
+	key := []byte(cmd.DeviceUDID)
+	if err := bkt.Put(key, devproto); err != nil {
+		return errors.Wrap(err, "put DeviceCommand to boltdb")
+	}
+	return tx.Commit()
+}
+
+func (db *Store) DeviceCommand(udid string) (*DeviceCommand, error) {
+	var dev DeviceCommand
+	err := db.View(func(tx *bolt.Tx) error {
+		b := tx.Bucket([]byte(DeviceCommandBucket))
+		v := b.Get([]byte(udid))
+		if v == nil {
+			return &notFound{"DeviceCommand", fmt.Sprintf("udid %s", udid)}
+		}
+		return UnmarshalDeviceCommand(v, &dev)
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &dev, nil
+}
+
+type notFound struct {
+	ResourceType string
+	Message      string
+}
+
+func (e *notFound) Error() string {
+	return fmt.Sprintf("not found: %s %s", e.ResourceType, e.Message)
+}
+
+func (db *Store) pollCommands(pubsub pubsub.PublishSubscriber) error {
+	commandEvents, err := pubsub.Subscribe(context.TODO(), "command-queue", command.CommandTopic)
+	if err != nil {
+		return errors.Wrapf(err,
+			"subscribing push to %s topic", command.CommandTopic)
+	}
+	go func() {
+		for {
+			select {
+			case event := <-commandEvents:
+				var ev command.Event
+				if err := command.UnmarshalEvent(event.Message, &ev); err != nil {
+					fmt.Println(err)
+					continue
+				}
+
+				cmd := new(DeviceCommand)
+				cmd.DeviceUDID = ev.DeviceUDID
+				byUDID, err := db.DeviceCommand(ev.DeviceUDID)
+				if err == nil && byUDID != nil {
+					cmd = byUDID
+				}
+				newPayload, err := plist.Marshal(&ev.Payload)
+				if err != nil {
+					fmt.Println(err)
+					continue
+				}
+				newCmd := Command{
+					UUID:    ev.Payload.CommandUUID,
+					Payload: newPayload,
+				}
+				cmd.Commands = append(cmd.Commands, newCmd)
+				if err := db.Save(cmd); err != nil {
+					fmt.Println(err)
+					continue
+				}
+				fmt.Printf("queued event for device: %s\n", ev.DeviceUDID)
+
+				cq := new(QueueCommandQueued)
+				cq.DeviceUDID = ev.DeviceUDID
+				cq.CommandUUID = ev.Payload.CommandUUID
+
+				msgBytes, err := MarshalQueuedCommand(cq)
+				if err != nil {
+					fmt.Println(err)
+					continue
+				}
+
+				pubsub.Publish(context.TODO(), CommandQueuedTopic, msgBytes)
+			}
+		}
+	}()
+
+	return nil
+}
+
+func isNotFound(err error) bool {
+	if _, ok := err.(*notFound); ok {
+		return true
+	}
+	return false
+}

platform/queue/queue_test.go

@@ -0,0 +1,178 @@
+package queue
+
+import (
+	"context"
+	"io/ioutil"
+	"os"
+	"testing"
+
+	"github.com/boltdb/bolt"
+	"github.com/micromdm/mdm"
+)
+
+func TestNext_Error(t *testing.T) {
+	store, teardown := setupDB(t)
+	defer teardown()
+
+	dc := &DeviceCommand{DeviceUDID: "TestDevice"}
+	dc.Commands = append(dc.Commands, Command{UUID: "xCmd"})
+	dc.Commands = append(dc.Commands, Command{UUID: "yCmd"})
+	dc.Commands = append(dc.Commands, Command{UUID: "zCmd"})
+	if err := store.Save(dc); err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := context.Background()
+	resp := mdm.Response{
+		UDID:        dc.DeviceUDID,
+		CommandUUID: "xCmd",
+		Status:      "Error",
+	}
+	for range dc.Commands {
+		cmd, err := store.Next(ctx, resp)
+		if err != nil {
+			t.Fatalf("expected nil, but got err: %s", err)
+		}
+		if cmd == nil {
+			t.Fatal("expected cmd but got nil")
+		}
+
+		if have, errd := cmd.UUID, resp.CommandUUID; have == errd {
+			t.Error("got back command which previously failed")
+		}
+	}
+}
+
+func TestNext_NotNow(t *testing.T) {
+	store, teardown := setupDB(t)
+	defer teardown()
+
+	dc := &DeviceCommand{DeviceUDID: "TestDevice"}
+	dc.Commands = append(dc.Commands, Command{UUID: "xCmd"})
+	dc.Commands = append(dc.Commands, Command{UUID: "yCmd"})
+	if err := store.Save(dc); err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := context.Background()
+	tf := func(t *testing.T) {
+
+
+		resp := mdm.Response{
+			UDID:        dc.DeviceUDID,
+			CommandUUID: "yCmd",
+			Status:      "NotNow",
+		}
+		cmd, err := store.Next(ctx, resp)
+
+		if err != nil {
+				t.Fatalf("expected nil, but got err: %s", err)
+		}
+
+		resp = mdm.Response{
+			UDID:        dc.DeviceUDID,
+			CommandUUID: cmd.UUID,
+			Status:      "NotNow",
+		}
+
+		cmd, err = store.Next(ctx, resp)
+		if err != nil {
+			t.Fatalf("expected nil, but got err: %s", err)
+		}
+		if cmd != nil {
+			t.Error("Got back a notnowed command.")
+		}
+	}
+
+	t.Run("withManyCommands", tf)
+	dc.Commands = []Command{{UUID: "xCmd"}}
+	if err := store.Save(dc); err != nil {
+		t.Fatal(err)
+	}
+	t.Run("withOneCommand", tf)
+}
+
+func TestNext_Idle(t *testing.T) {
+	store, teardown := setupDB(t)
+	defer teardown()
+
+	dc := &DeviceCommand{DeviceUDID: "TestDevice"}
+	dc.Commands = append(dc.Commands, Command{UUID: "xCmd"})
+	dc.Commands = append(dc.Commands, Command{UUID: "yCmd"})
+	dc.Commands = append(dc.Commands, Command{UUID: "zCmd"})
+	if err := store.Save(dc); err != nil {
+		t.Fatal(err)
+	}
+
+	ctx := context.Background()
+	resp := mdm.Response{
+		UDID:        dc.DeviceUDID,
+		CommandUUID: "xCmd",
+		Status:      "Idle",
+	}
+	for i, _ := range dc.Commands {
+		cmd, err := store.Next(ctx, resp)
+		if err != nil {
+			t.Fatalf("expected nil, but got err: %s", err)
+		}
+		if cmd == nil {
+			t.Fatal("expected cmd but got nil")
+		}
+
+		if have, want := cmd.UUID, dc.Commands[i].UUID; have != want {
+			t.Errorf("have %s, want %s, index %d", have, want, i)
+		}
+	}
+}
+
+func TestNext_zeroCommands(t *testing.T) {
+	store, teardown := setupDB(t)
+	defer teardown()
+
+	dc := &DeviceCommand{DeviceUDID: "TestDevice"}
+	if err := store.Save(dc); err != nil {
+		t.Fatal(err)
+	}
+
+	var allStatuses = []string{
+		"Acknowledged",
+		"NotNow",
+	}
+
+	ctx := context.Background()
+	for _, s := range allStatuses {
+		t.Run(s, func(t *testing.T) {
+			resp := mdm.Response{CommandUUID: s, Status: s}
+			cmd, err := store.Next(ctx, resp)
+			if err != nil {
+				t.Errorf("expected nil, but got err: %s", err)
+			}
+			if cmd != nil {
+				t.Errorf("expected nil cmd but got %s", cmd.UUID)
+			}
+		})
+	}
+
+}
+
+func setupDB(t *testing.T) (*Store, func()) {
+	f, _ := ioutil.TempFile("", "bolt-")
+	teardown := func() {
+		f.Close()
+		os.Remove(f.Name())
+	}
+
+	db, err := bolt.Open(f.Name(), 0777, nil)
+	if err != nil {
+		t.Fatalf("couldn't open bolt, err %s\n", err)
+	}
+	err = db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucketIfNotExists([]byte(DeviceCommandBucket))
+		return err
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	store := &Store{db}
+	return store, teardown
+}