Skip to content
Permalink
Branch: master
Find file Copy path
Find file Copy path
1 contributor

Users who have contributed to this file

186 lines (165 sloc) 4.47 KB
package profilesvc
import (
"context"
"errors"
"sync"
)
// Service is a simple CRUD interface for user profiles.
type Service interface {
PostProfile(ctx context.Context, p Profile) error
GetProfile(ctx context.Context, id string) (Profile, error)
PutProfile(ctx context.Context, id string, p Profile) error
PatchProfile(ctx context.Context, id string, p Profile) error
DeleteProfile(ctx context.Context, id string) error
GetAddresses(ctx context.Context, profileID string) ([]Address, error)
GetAddress(ctx context.Context, profileID string, addressID string) (Address, error)
PostAddress(ctx context.Context, profileID string, a Address) error
DeleteAddress(ctx context.Context, profileID string, addressID string) error
}
// Profile represents a single user profile.
// ID should be globally unique.
type Profile struct {
ID string `json:"id"`
Name string `json:"name,omitempty"`
Addresses []Address `json:"addresses,omitempty"`
}
// Address is a field of a user profile.
// ID should be unique within the profile (at a minimum).
type Address struct {
ID string `json:"id"`
Location string `json:"location,omitempty"`
}
var (
ErrInconsistentIDs = errors.New("inconsistent IDs")
ErrAlreadyExists = errors.New("already exists")
ErrNotFound = errors.New("not found")
)
type inmemService struct {
mtx sync.RWMutex
m map[string]Profile
}
func NewInmemService() Service {
return &inmemService{
m: map[string]Profile{},
}
}
func (s *inmemService) PostProfile(ctx context.Context, p Profile) error {
s.mtx.Lock()
defer s.mtx.Unlock()
if _, ok := s.m[p.ID]; ok {
return ErrAlreadyExists // POST = create, don't overwrite
}
s.m[p.ID] = p
return nil
}
func (s *inmemService) GetProfile(ctx context.Context, id string) (Profile, error) {
s.mtx.RLock()
defer s.mtx.RUnlock()
p, ok := s.m[id]
if !ok {
return Profile{}, ErrNotFound
}
return p, nil
}
func (s *inmemService) PutProfile(ctx context.Context, id string, p Profile) error {
if id != p.ID {
return ErrInconsistentIDs
}
s.mtx.Lock()
defer s.mtx.Unlock()
s.m[id] = p // PUT = create or update
return nil
}
func (s *inmemService) PatchProfile(ctx context.Context, id string, p Profile) error {
if p.ID != "" && id != p.ID {
return ErrInconsistentIDs
}
s.mtx.Lock()
defer s.mtx.Unlock()
existing, ok := s.m[id]
if !ok {
return ErrNotFound // PATCH = update existing, don't create
}
// We assume that it's not possible to PATCH the ID, and that it's not
// possible to PATCH any field to its zero value. That is, the zero value
// means not specified. The way around this is to use e.g. Name *string in
// the Profile definition. But since this is just a demonstrative example,
// I'm leaving that out.
if p.Name != "" {
existing.Name = p.Name
}
if len(p.Addresses) > 0 {
existing.Addresses = p.Addresses
}
s.m[id] = existing
return nil
}
func (s *inmemService) DeleteProfile(ctx context.Context, id string) error {
s.mtx.Lock()
defer s.mtx.Unlock()
if _, ok := s.m[id]; !ok {
return ErrNotFound
}
delete(s.m, id)
return nil
}
func (s *inmemService) GetAddresses(ctx context.Context, profileID string) ([]Address, error) {
s.mtx.RLock()
defer s.mtx.RUnlock()
p, ok := s.m[profileID]
if !ok {
return []Address{}, ErrNotFound
}
return p.Addresses, nil
}
func (s *inmemService) GetAddress(ctx context.Context, profileID string, addressID string) (Address, error) {
s.mtx.RLock()
defer s.mtx.RUnlock()
p, ok := s.m[profileID]
if !ok {
return Address{}, ErrNotFound
}
for _, address := range p.Addresses {
if address.ID == addressID {
return address, nil
}
}
return Address{}, ErrNotFound
}
func (s *inmemService) PostAddress(ctx context.Context, profileID string, a Address) error {
s.mtx.Lock()
defer s.mtx.Unlock()
p, ok := s.m[profileID]
if !ok {
return ErrNotFound
}
for _, address := range p.Addresses {
if address.ID == a.ID {
return ErrAlreadyExists
}
}
p.Addresses = append(p.Addresses, a)
s.m[profileID] = p
return nil
}
func (s *inmemService) DeleteAddress(ctx context.Context, profileID string, addressID string) error {
s.mtx.Lock()
defer s.mtx.Unlock()
p, ok := s.m[profileID]
if !ok {
return ErrNotFound
}
newAddresses := make([]Address, 0, len(p.Addresses))
for _, address := range p.Addresses {
if address.ID == addressID {
continue // delete
}
newAddresses = append(newAddresses, address)
}
if len(newAddresses) == len(p.Addresses) {
return ErrNotFound
}
p.Addresses = newAddresses
s.m[profileID] = p
return nil
}
You can’t perform that action at this time.