ducky/devices
2015-12-19
Parent:1ae5bae472c1
ducky/devices/memstore.go
Fix JSON pointers in errors when creating devices. Our JSON pointers used to point at the root of the document, but the properties were actually in objects in an array keyed off of "devices", so we had to update the field property of our errors to match. While we were in there, we fixed the "insufficient" error for a Device's name to be "missing" when the name is an empty string. So far, the only way for a Device's name for it to be insufficient is _for it to be the empty string_, but if in the future we raise the minimum length of the Device name, there will be a distinction and I'd like the code to recognise it.
| paddy@4 | 1 package devices |
| paddy@4 | 2 |
| paddy@4 | 3 import ( |
| paddy@4 | 4 "sync" |
| paddy@4 | 5 |
| paddy@4 | 6 "code.secondbit.org/uuid.hg" |
| paddy@4 | 7 "golang.org/x/net/context" |
| paddy@4 | 8 ) |
| paddy@4 | 9 |
| paddy@12 | 10 // Memstore is an in-memory implementation of Storer, and should |
| paddy@12 | 11 // only be used for testing or for temporary local servers. |
| paddy@4 | 12 type Memstore struct { |
| paddy@4 | 13 devices map[string]Device |
| paddy@4 | 14 lock sync.RWMutex |
| paddy@4 | 15 } |
| paddy@4 | 16 |
| paddy@12 | 17 // NewMemstore returns a Memstore that is ready to be used as a |
| paddy@12 | 18 // Storer implementation. |
| paddy@4 | 19 func NewMemstore() *Memstore { |
| paddy@4 | 20 return &Memstore{ |
| paddy@4 | 21 devices: map[string]Device{}, |
| paddy@4 | 22 } |
| paddy@4 | 23 } |
| paddy@4 | 24 |
| paddy@12 | 25 // GetDevices returns any Devices in the Memstore that match the |
| paddy@12 | 26 // passed IDs. If an ID cannot be matched to a Device in the |
| paddy@12 | 27 // Memstore, it is ignored. The result is a map, with the values |
| paddy@12 | 28 // being the Devices that could be found, and the keys being the |
| paddy@12 | 29 // result of the String() method for each Device's ID. |
| paddy@12 | 30 // |
| paddy@12 | 31 // An empty map is a possible response, if none of the IDs could |
| paddy@12 | 32 // be found. |
| paddy@4 | 33 func (m *Memstore) GetDevices(ids []uuid.ID, c context.Context) (map[string]Device, error) { |
| paddy@4 | 34 m.lock.RLock() |
| paddy@4 | 35 defer m.lock.RUnlock() |
| paddy@4 | 36 |
| paddy@4 | 37 results := map[string]Device{} |
| paddy@4 | 38 |
| paddy@4 | 39 for _, id := range ids { |
| paddy@4 | 40 device, ok := m.devices[id.String()] |
| paddy@4 | 41 if !ok { |
| paddy@4 | 42 continue |
| paddy@4 | 43 } |
| paddy@4 | 44 results[id.String()] = device |
| paddy@4 | 45 } |
| paddy@4 | 46 return results, nil |
| paddy@4 | 47 } |
| paddy@4 | 48 |
| paddy@12 | 49 // UpdateDevice applies the passed DeviceChange to the Device |
| paddy@12 | 50 // in the Memstore specified by the DeviceChange's DeviceID |
| paddy@12 | 51 // property. If no Device in the Memstore matches the DeviceChange's |
| paddy@12 | 52 // DeviceID property, then an ErrDeviceNotFound error will be |
| paddy@12 | 53 // returned. |
| paddy@4 | 54 func (m *Memstore) UpdateDevice(change DeviceChange, c context.Context) error { |
| paddy@10 | 55 m.lock.Lock() |
| paddy@10 | 56 defer m.lock.Unlock() |
| paddy@10 | 57 |
| paddy@10 | 58 device, ok := m.devices[change.DeviceID.String()] |
| paddy@10 | 59 if !ok { |
| paddy@11 | 60 return ErrDeviceNotFound |
| paddy@10 | 61 } |
| paddy@10 | 62 |
| paddy@10 | 63 device = ApplyChange(device, change) |
| paddy@10 | 64 m.devices[change.DeviceID.String()] = device |
| paddy@10 | 65 |
| paddy@4 | 66 return nil |
| paddy@4 | 67 } |
| paddy@4 | 68 |
| paddy@12 | 69 // DeleteDevices will remove any Devices from the Memstore that match |
| paddy@12 | 70 // the IDs passed in. If an ID can't be matched to a Device in the |
| paddy@12 | 71 // Memstore, then it is ignored. |
| paddy@14 | 72 func (m *Memstore) DeleteDevices(ids []uuid.ID, c context.Context) error { |
| paddy@14 | 73 m.lock.Lock() |
| paddy@14 | 74 defer m.lock.Unlock() |
| paddy@14 | 75 |
| paddy@14 | 76 for _, id := range ids { |
| paddy@14 | 77 delete(m.devices, id.String()) |
| paddy@14 | 78 } |
| paddy@14 | 79 |
| paddy@4 | 80 return nil |
| paddy@4 | 81 } |
| paddy@4 | 82 |
| paddy@12 | 83 // CreateDevices stores the passed devices in the Memstore as a single |
| paddy@12 | 84 // transaction. If a Device's ID already exists in the Memstore, an |
| paddy@12 | 85 // ErrDeviceAlreadyExists error with that Device's ID is returned, and |
| paddy@12 | 86 // none of the passed Devices are stored. |
| paddy@4 | 87 func (m *Memstore) CreateDevices(devices []Device, c context.Context) error { |
| paddy@4 | 88 m.lock.Lock() |
| paddy@4 | 89 defer m.lock.Unlock() |
| paddy@4 | 90 |
| paddy@4 | 91 for _, device := range devices { |
| paddy@5 | 92 if _, ok := m.devices[device.ID.String()]; ok { |
| paddy@5 | 93 return ErrDeviceAlreadyExists(device.ID) |
| paddy@5 | 94 } |
| paddy@5 | 95 } |
| paddy@5 | 96 |
| paddy@5 | 97 for _, device := range devices { |
| paddy@4 | 98 m.devices[device.ID.String()] = device |
| paddy@4 | 99 } |
| paddy@4 | 100 return nil |
| paddy@4 | 101 } |
| paddy@4 | 102 |
| paddy@12 | 103 // ListDevicesByOwner returns all the Devices in the Memstore that have an |
| paddy@12 | 104 // Owner property that matches the passed ID. If no Devices have an Owner |
| paddy@12 | 105 // property matching the passed ID, an empty slice is returned. |
| paddy@12 | 106 // |
| paddy@12 | 107 // ListDevicesByOwner does not guarantee any sort order for the Devices. |
| paddy@4 | 108 func (m *Memstore) ListDevicesByOwner(user uuid.ID, c context.Context) ([]Device, error) { |
| paddy@8 | 109 var devices []Device |
| paddy@8 | 110 for _, device := range m.devices { |
| paddy@8 | 111 if !device.Owner.Equal(user) { |
| paddy@8 | 112 continue |
| paddy@8 | 113 } |
| paddy@8 | 114 devices = append(devices, device) |
| paddy@8 | 115 } |
| paddy@8 | 116 return devices, nil |
| paddy@4 | 117 } |