User creation, DB transactions, createdb flag changes.

api/handler.go

@@ -19,6 +19,7 @@ var (
 func Handler() *mux.Router {
 	m := router.API()
 	m.Get(router.User).Handler(handler(serveUser))
+	m.Get(router.CreateUser).Handler(handler(serveCreateUser))
 	m.Get(router.Users).Handler(handler(serveUsers))
 	return m
 }

api/users.go

@@ -1,6 +1,7 @@
 package api
 
 import (
+	"encoding/json"
 	"strconv"
 
 	"github.com/gorilla/mux"
@@ -24,6 +25,24 @@ func serveUser(w http.ResponseWriter, r *http.Request) error {
 	return writeJSON(w, user)
 }
 
+func serveCreateUser(w http.ResponseWriter, r *http.Request) error {
+	var user models.User
+	err := json.NewDecoder(r.Body).Decode(&user)
+	if err != nil {
+		return err
+	}
+
+	created, err := store.Users.Create(&user)
+	if err != nil {
+		return err
+	}
+	if created {
+		w.WriteHeader(http.StatusCreated)
+	}
+
+	return writeJSON(w, user)
+}
+
 func serveUsers(w http.ResponseWriter, r *http.Request) error {
 	var opt models.UserListOptions
 	if err := schemaDecoder.Decode(&opt, r.URL.Query()); err != nil {

cmd/bactdb/bactdb.go

@@ -63,7 +63,7 @@ type subcmd struct {
 
 var subcmds = []subcmd{
 	{"serve", "start web server", serveCmd},
-	{"create-db", "create the database schema", createDBCmd},
+	{"createdb", "create the database schema", createDBCmd},
 }
 
 func serveCmd(args []string) {
@@ -98,9 +98,10 @@ The options are:
 }
 
 func createDBCmd(args []string) {
-	fs := flag.NewFlagSet("create-db", flag.ExitOnError)
+	fs := flag.NewFlagSet("createdb", flag.ExitOnError)
+	drop := fs.Bool("drop", false, "drop DB before creating")
 	fs.Usage = func() {
-		fmt.Fprintln(os.Stderr, `usage: bactdb create-db [options]
+		fmt.Fprintln(os.Stderr, `usage: bactdb createdb [options]
 
 Creates the necessary DB schema.
 
@@ -116,5 +117,8 @@ The options are:
 	}
 
 	datastore.Connect()
+	if *drop {
+		datastore.Drop()
+	}
 	datastore.Create()
 }

datastore/datastore.go

@@ -22,3 +22,9 @@ func NewDatastore(dbh modl.SqlExecutor) *Datastore {
 	d.Users = &usersStore{d}
 	return d
 }
+
+func NewMockDatastore() *Datastore {
+	return &Datastore{
+		Users: &models.MockUsersService{},
+	}
+}

datastore/db.go

@@ -51,3 +51,35 @@ func Drop() {
 	// TODO(mrd): raise errors.
 	DB.DropTables()
 }
+
+// transact calls fn in a DB transaction. If dbh is a transaction, then it just calls
+// the function. Otherwise, it begins a transaction, rolling back on failure and
+// committing on success.
+func transact(dbh modl.SqlExecutor, fn func(fbh modl.SqlExecutor) error) error {
+	var sharedTx bool
+	tx, sharedTx := dbh.(*modl.Transaction)
+	if !sharedTx {
+		var err error
+		tx, err = dbh.(*modl.DbMap).Begin()
+		if err != nil {
+			return err
+		}
+		defer func() {
+			if err != nil {
+				tx.Rollback()
+			}
+		}()
+	}
+
+	if err := fn(tx); err != nil {
+		return err
+	}
+
+	if !sharedTx {
+		if err := tx.Commit(); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

datastore/users.go

@@ -1,6 +1,14 @@
 package datastore
 
-import "github.com/thermokarst/bactdb/models"
+import (
+	"fmt"
+	"math/rand"
+	"strings"
+	"time"
+
+	"github.com/jmoiron/modl"
+	"github.com/thermokarst/bactdb/models"
+)
 
 func init() {
 	DB.AddTableWithName(models.User{}, "users").SetKeys(true, "Id")
@@ -24,6 +32,46 @@ func (s *usersStore) Get(id int64) (*models.User, error) {
 	return users[0], nil
 }
 
+func (s *usersStore) Create(user *models.User) (bool, error) {
+	retries := 3
+	var wantRetry bool
+
+retry:
+	retries--
+	wantRetry = false
+	if retries == 0 {
+		return false, fmt.Errorf("failed to create user with username %q after retrying", user.UserName)
+	}
+
+	var created bool
+	err := transact(s.dbh, func(tx modl.SqlExecutor) error {
+		var existing []*models.User
+		if err := tx.Select(&existing, `SELECT * FROM users WHERE username=$1 LIMIT 1;`, user.UserName); err != nil {
+			return err
+		}
+		if len(existing) > 0 {
+			*user = *existing[0]
+			return nil
+		}
+
+		if err := tx.Insert(user); err != nil {
+			if strings.Contains(err.Error(), `violates unique constraint "username_idx"`) {
+				time.Sleep(time.Duration(rand.Intn(75)) * time.Millisecond)
+				wantRetry = true
+				return err
+			}
+			return err
+		}
+
+		created = true
+		return nil
+	})
+	if wantRetry {
+		goto retry
+	}
+	return created, err
+}
+
 func (s *usersStore) List(opt *models.UserListOptions) ([]*models.User, error) {
 	if opt == nil {
 		opt = &models.UserListOptions{}

datastore/users_test.go

@@ -12,6 +12,7 @@ func TestUsersStore_Get_db(t *testing.T) {
 
 	tx, _ := DB.Begin()
 	defer tx.Rollback()
+
 	// Test on a clean database
 	tx.Exec(`DELETE FROM users;`)
 	if err := tx.Insert(want); err != nil {
@@ -30,10 +31,32 @@ func TestUsersStore_Get_db(t *testing.T) {
 	}
 }
 
+func TestUsersStore_Create_db(t *testing.T) {
+	user := &models.User{Id: 1, UserName: "Test User"}
+
+	tx, _ := DB.Begin()
+	defer tx.Rollback()
+
+	// Test on a clean database
+	tx.Exec(`DELETE FROM users;`)
+
+	d := NewDatastore(tx)
+	created, err := d.Users.Create(user)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !created {
+		t.Error("!created")
+	}
+	if user.Id == 0 {
+		t.Error("want nonzero user.Id after submitting")
+	}
+}
+
 func TestUsersStore_List_db(t *testing.T) {
 	want := []*models.User{{Id: 1, UserName: "Test User"}}
 
-	// tx := DBH
 	tx, _ := DB.Begin()
 	defer tx.Rollback()
 

models/users.go

@@ -2,6 +2,7 @@ package models
 
 import (
 	"errors"
+	"net/http"
 	"strconv"
 	"time"
 
@@ -24,6 +25,9 @@ type UsersService interface {
 
 	// List all users.
 	List(opt *UserListOptions) ([]*User, error)
+
+	// Create a new user. The newly created user's ID is written to user.Id
+	Create(user *User) (created bool, err error)
 }
 
 var (
@@ -58,6 +62,25 @@ func (s *usersService) Get(id int64) (*User, error) {
 	return user, nil
 }
 
+func (s *usersService) Create(user *User) (bool, error) {
+	url, err := s.client.url(router.CreateUser, nil, nil)
+	if err != nil {
+		return false, err
+	}
+
+	req, err := s.client.NewRequest("POST", url.String(), user)
+	if err != nil {
+		return false, err
+	}
+
+	resp, err := s.client.Do(req, &user)
+	if err != nil {
+		return false, err
+	}
+
+	return resp.StatusCode == http.StatusCreated, nil
+}
+
 type UserListOptions struct {
 	ListOptions
 }
@@ -83,10 +106,13 @@ func (s *usersService) List(opt *UserListOptions) ([]*User, error) {
 }
 
 type MockUsersService struct {
-	Get_  func(id int64) (*User, error)
+	Get_    func(id int64) (*User, error)
-	List_ func(opt *UserListOptions) ([]*User, error)
+	List_   func(opt *UserListOptions) ([]*User, error)
+	Create_ func(post *User) (bool, error)
 }
 
+var _ UsersService = &MockUsersService{}
+
 func (s *MockUsersService) Get(id int64) (*User, error) {
 	if s.Get_ == nil {
 		return nil, nil
@@ -94,6 +120,13 @@ func (s *MockUsersService) Get(id int64) (*User, error) {
 	return s.Get_(id)
 }
 
+func (s *MockUsersService) Create(user *User) (bool, error) {
+	if s.Create_ == nil {
+		return false, nil
+	}
+	return s.Create_(user)
+}
+
 func (s *MockUsersService) List(opt *UserListOptions) ([]*User, error) {
 	if s.List_ == nil {
 		return nil, nil

models/users_test.go

@@ -38,6 +38,42 @@ func TestUsersService_Get(t *testing.T) {
 	}
 }
 
+func TestUsersService_Create(t *testing.T) {
+	setup()
+	defer teardown()
+
+	want := &User{Id: 1, UserName: "Test User"}
+
+	var called bool
+	mux.HandleFunc(urlPath(t, router.CreateUser, nil), func(w http.ResponseWriter, r *http.Request) {
+		called = true
+		testMethod(t, r, "POST")
+		testBody(t, r, `{"id":1,"user_name":"Test User","created_at":"0001-01-01T00:00:00Z","updated_at":"0001-01-01T00:00:00Z","deleted_at":"0001-01-01T00:00:00Z"}`+"\n")
+
+		w.WriteHeader(http.StatusCreated)
+		writeJSON(w, want)
+	})
+
+	user := &User{Id: 1, UserName: "Test User"}
+	created, err := client.Users.Create(user)
+	if err != nil {
+		t.Errorf("Users.Create returned error: %v", err)
+	}
+
+	if !created {
+		t.Error("!created")
+	}
+
+	if !called {
+		t.Fatal("!called")
+	}
+
+	normalizeTime(&want.CreatedAt, &want.UpdatedAt, &want.DeletedAt)
+	if !reflect.DeepEqual(user, want) {
+		t.Errorf("Users.Create returned %+v, want %+v", user, want)
+	}
+}
+
 func TestUsersService_List(t *testing.T) {
 	setup()
 	defer teardown()

router/api.go

@@ -5,6 +5,7 @@ import "github.com/gorilla/mux"
 func API() *mux.Router {
 	m := mux.NewRouter()
 	m.Path("/users").Methods("GET").Name(Users)
+	m.Path("/users").Methods("POST").Name(CreateUser)
 	m.Path("/users/{Id:.+}").Methods("GET").Name(User)
 	return m
 }

router/routes.go

@@ -1,6 +1,7 @@
 package router
 
 const (
-	User  = "user"
+	User       = "user"
-	Users = "users"
+	CreateUser = "user:create"
+	Users      = "users"
 )