[GO-4] Cassandra - Handler Queries

scripts/data.cql

@@ -0,0 +1,18 @@
+-- Create a keyspace
+CREATE KEYSPACE IF NOT EXISTS store WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : '1' };
+
+-- Create a table
+CREATE TABLE IF NOT EXISTS store.users (
+                                                   id uuid PRIMARY KEY,
+                                                   name text,
+                                                   email_address text,
+                                                   last_updated_timestamp timestamp
+);
+
+-- Insert some data
+INSERT INTO store.users
+(id, name, email_address, last_updated_timestamp)
+VALUES (uuid(), 'John', 'john@test.com',toTimeStamp(now()));
+INSERT INTO store.users
+(id, name, email_address, last_updated_timestamp)
+VALUES (uuid(), 'Paul', 'paul@test.com',toTimeStamp(now()));

src/main.go

@@ -6,15 +6,10 @@ import (
 	"encoding/json"
 	"github.com/gocql/gocql"
 	"github.com/gorilla/mux"
-	"log"
 	"net/http"
-	"time"
 )
 
 func main() {
-	session := cassandra.SetupCassandra()
-	defer session.Close()
-
 	usersHandler := NewUsersHandler()
 	// Create the router
 	router := mux.NewRouter()
@@ -49,31 +44,71 @@ func NewUsersHandler() *UsersHandler {
 	return &UsersHandler{}
 }
 
-func (h UsersHandler) CreateUser(w http.ResponseWriter, r *http.Request) {}
-func (h UsersHandler) ListUsers(w http.ResponseWriter, r *http.Request) {
-	log.Printf("get users")
-	var user = users.User{ID: gocql.UUIDFromTime(time.Now()), Name: "Max", EmailAddress: "test@test.com", Birthday: time.Now()}
+func (h UsersHandler) CreateUser(w http.ResponseWriter, r *http.Request) {
+	var user users.User
+	if err := json.NewDecoder(r.Body).Decode(&user); err != nil {
+		InternalServerErrorHandler(w, r)
+		return
+	}
+
+	ctx := r.Context()
+
+	session := cassandra.SetupCassandra()
+	defer session.Close()
+
+	err := session.Query("INSERT INTO store.users (id, name, email_address, last_updated_timestamp) VALUES (?,?,?,?)", user.ID, user.Name, user.EmailAddress, user.LastUpdatedTimestamp).WithContext(ctx).Exec()
+	if err != nil {
+		InternalServerErrorHandler(w, r)
+		return
+	}
+
+	w.WriteHeader(http.StatusCreated)
+	json.NewEncoder(w).Encode(user)
+}
+
+func (h UsersHandler) ListUsers(w http.ResponseWriter, r *http.Request) {}
+func (h UsersHandler) GetUser(w http.ResponseWriter, r *http.Request) {
+	id := mux.Vars(r)["id"]
+
+	ctx := r.Context()
+
+	session := cassandra.SetupCassandra()
+	defer session.Close()
+
+	var user users.User
+	queryString := "SELECT id, name, email_address, last_updated_timestamp FROM store.users WHERE id = ? LIMIT 1"
+	err := session.Query(queryString, id).Consistency(gocql.One).WithContext(ctx).Scan(&user.ID, &user.Name, &user.EmailAddress, &user.LastUpdatedTimestamp)
+	if err != nil {
+		NotFoundHandler(w, r)
+		return
+	}
+
 	jsonBytes, err := json.Marshal(user)
 	if err != nil {
 		InternalServerErrorHandler(w, r)
 		return
 	}
-	w.WriteHeader(http.StatusOK)
+
 	_, err = w.Write(jsonBytes)
 	if err != nil {
 		return
 	}
 }
-func (h UsersHandler) GetUser(w http.ResponseWriter, r *http.Request)    {}
 func (h UsersHandler) UpdateUser(w http.ResponseWriter, r *http.Request) {}
 func (h UsersHandler) DeleteUser(w http.ResponseWriter, r *http.Request) {}
 
 func InternalServerErrorHandler(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusInternalServerError)
-	w.Write([]byte("500 Internal Server Error"))
+	_, err := w.Write([]byte("500 Internal Server Error"))
+	if err != nil {
+		return
+	}
 }
 
 func NotFoundHandler(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusNotFound)
-	w.Write([]byte("404 Not Found"))
+	_, err := w.Write([]byte("404 Not Found"))
+	if err != nil {
+		return
+	}
 }

src/users/user.go

@@ -7,8 +7,8 @@ import (
 
 // User represents data about a record User.
 type User struct {
-	ID           gocql.UUID `json:"id"`
-	Name         string     `json:"name"`
-	EmailAddress string     `json:"emailAddress"`
-	Birthday     time.Time  `json:"birthday"`
+	ID                   gocql.UUID `cql:"id" json:"id"`
+	Name                 string     `cql:"name" json:"name"`
+	EmailAddress         string     `cql:"emailAddress" json:"emailAddress"`
+	LastUpdatedTimestamp time.Time  `cql:"lastUpdatedTimestamp" json:"lastUpdatedTimestamp"`
 }