implement a metrics endpoint as well as a user get/one endpoint

controllers/health.go

@@ -1,9 +1,32 @@
 package controllers
 
-import "net/http"
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/hbjydev/mangadex-next/database"
+)
 
 type HealthController struct{}
 
 func (h *HealthController) Healthy(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusOK)
 }
+
+func (h *HealthController) Metrics(w http.ResponseWriter, r *http.Request) {
+	var output string
+
+	output += fmt.Sprintf("mangadex_item_count{type=\"user\"} %v\n", countUsers())
+
+	w.Write([]byte(output))
+	w.WriteHeader(http.StatusOK)
+}
+
+func countUsers() int {
+	row := database.DB.QueryRow("SELECT count(id) FROM users")
+	var count int
+	if err := row.Scan(&count); err != nil {
+		return -1
+	}
+	return count
+}

controllers/user.go

@@ -0,0 +1,56 @@
+package controllers
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+
+	"github.com/gorilla/mux"
+	"github.com/hbjydev/mangadex-next/models"
+)
+
+type UserController struct{}
+
+func (u *UserController) GetAll(w http.ResponseWriter, r *http.Request) {
+	users, err := models.GetUsers()
+	if err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	usersJSON, err := json.Marshal(users)
+	if err != nil {
+		log.Println("/users: failed to marshal users array")
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	w.Header().Add("Content-Type", "application/json; charset=utf-8")
+	w.WriteHeader(http.StatusOK)
+	w.Write(usersJSON)
+}
+
+func (u *UserController) GetOne(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+
+	user, err := models.UserByUsername(vars["username"])
+	if err != nil {
+		if err.Error() == "sql: no rows in result set" {
+			w.WriteHeader(http.StatusNotFound)
+		} else {
+			w.WriteHeader(http.StatusInternalServerError)
+		}
+		return
+	}
+
+	userJSON, err := user.Normalize()
+	if err != nil {
+		log.Printf("/user/%v: failed to marshal user", vars["username"])
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	w.Header().Add("Content-Type", "application/json; charset=utf-8")
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(*userJSON))
+}

docs/openapi.yml

@@ -17,6 +17,8 @@ schemes:
 tags:
   - name: health
     description: 'Service health endpoints'
+  - name: users
+    description: 'Service user endpoints'
 
 paths:
   /-/healthy:
@@ -28,4 +30,39 @@ paths:
       responses:
         '200':
           description: 'Everything is healthy.'
+  /-/metrics:
+    get:
+      summary: Retrieves some metrics about the API server and database.
+      operationId: metrics
+      tags:
+        - health
+      responses:
+        '200':
+          description: 'A Prometheus-compatible metrics list.'
 
+  /users:
+    get:
+      summary: Retrieves every user in the database.
+      operationId: getAllUsers
+      tags:
+        - users
+      responses:
+        '200':
+          description: 'All users in the database.'
+
+  /users/{username}:
+    get:
+      summary: Retrieves a single user from the database.
+      operationId: getOneUser
+      tags:
+        - users
+      parameters:
+        - in: path
+          name: username
+          schema:
+            type: string
+          required: true
+          description: The username of the user you want information on.
+      responses:
+        '200':
+          description: 'A single user from the database.'

main.go

@@ -42,6 +42,9 @@ func main() {
 	healthRouter := routers.HealthRouter{}
 	healthRouter.RegisterRoutes(r)
 
+	userRouter := routers.UserRouter{}
+	userRouter.RegisterRoutes(r)
+
 	log.Println("Starting server on :3000...")
 	log.Fatal(http.ListenAndServe(":3000", r))
 }

models/user.go

@@ -11,11 +11,10 @@ import (
 	"golang.org/x/crypto/bcrypt"
 )
 
-type password string
 type User struct {
 	ID        string    `json:"id"`
 	Username  string    `json:"username"`
-	Password  password  `json:"password"`
+	Password  string    `json:"-"`
 	Email     string    `json:"email"`
 	LevelID   string    `json:"level_id"`
 	JoinedAt  time.Time `json:"joined_at"`
@@ -30,8 +29,59 @@ type User struct {
 	AvatarURL string    `json:"avatar"`
 }
 
-func (password) MarshalJSON() ([]byte, error) {
-	return []byte(`""`), nil
+func GetUsers() ([]User, error) {
+	rows, err := database.DB.Query(`
+        SELECT
+            hex(id), username, email, password, level_id, last_seen, website,
+            biography, views, uploads, premium, md_at_home, avatar_url,
+            joined_at, update_at
+        FROM users
+    `)
+	if err != nil {
+		log.Printf("Users: error at SQL query: %v\n", err)
+		return nil, err
+	}
+	defer rows.Close()
+
+	users := make([]User, 0)
+	for rows.Next() {
+		var u User
+		var ls mysql.NullTime
+		var ja mysql.NullTime
+		var ua mysql.NullTime
+
+		if err := rows.Scan(&u.ID, &u.Username, &u.Email, &u.Password, &u.LevelID,
+			&ls, &u.Website, &u.Biography, &u.Views, &u.Uploads, &u.Premium,
+			&u.MDAtHome, &u.AvatarURL, &ja, &ua); err != nil {
+			log.Printf("UserByUsername: error at SQL query: %v\n", err)
+			return nil, err
+		}
+
+		if ls.Valid {
+			u.LastSeen = ls.Time
+		} else {
+			log.Printf("UserByUsername: invalid SQL datetime value (id %v)\n", u.ID)
+			return nil, errors.New("invalid sql datetime value")
+		}
+
+		if ja.Valid {
+			u.JoinedAt = ja.Time
+		} else {
+			log.Printf("UserByUsername: invalid SQL datetime value (id %v)\n", u.ID)
+			return nil, errors.New("invalid sql datetime value")
+		}
+
+		if ua.Valid {
+			u.UpdateAt = ua.Time
+		} else {
+			log.Printf("UserByUsername: invalid SQL datetime value (id %v)\n", u.ID)
+			return nil, errors.New("invalid sql datetime value")
+		}
+
+		users = append(users, u)
+	}
+
+	return users, nil
 }
 
 func UserByUsername(username string) (*User, error) {
@@ -39,7 +89,8 @@ func UserByUsername(username string) (*User, error) {
         SELECT
             hex(id), username, email, password, level_id, last_seen, website,
             biography, views, uploads, premium, md_at_home, avatar_url,
-            joined_at, update_at FROM users
+            joined_at, update_at
+        FROM users
         WHERE username = ?
     `, username)
 

routers/health.go

@@ -7,17 +7,19 @@ import (
 	"github.com/hbjydev/mangadex-next/controllers"
 )
 
-type HealthRouter struct {
-	Controller controllers.HealthController
-}
+type HealthRouter struct{}
 
 func (h *HealthRouter) healthcheck(w http.ResponseWriter, r *http.Request) {
 	controller := controllers.HealthController{}
 	controller.Healthy(w, r)
 }
 
-func (h *HealthRouter) RegisterRoutes(r *mux.Router) {
-	pathPrefix := r.PathPrefix("/-")
-
-	pathPrefix.Path("/healthy").HandlerFunc(h.healthcheck).Methods("GET")
+func (h *HealthRouter) metrics(w http.ResponseWriter, r *http.Request) {
+	controller := controllers.HealthController{}
+	controller.Metrics(w, r)
+}
+
+func (h *HealthRouter) RegisterRoutes(r *mux.Router) {
+	r.HandleFunc("/-/healthy", h.healthcheck)
+	r.HandleFunc("/-/metrics", h.metrics)
 }

routers/user.go

@@ -0,0 +1,25 @@
+package routers
+
+import (
+	"net/http"
+
+	"github.com/gorilla/mux"
+	"github.com/hbjydev/mangadex-next/controllers"
+)
+
+type UserRouter struct{}
+
+func (u *UserRouter) getAll(w http.ResponseWriter, r *http.Request) {
+	controller := controllers.UserController{}
+	controller.GetAll(w, r)
+}
+
+func (u *UserRouter) getOne(w http.ResponseWriter, r *http.Request) {
+	controller := controllers.UserController{}
+	controller.GetOne(w, r)
+}
+
+func (u *UserRouter) RegisterRoutes(r *mux.Router) {
+	r.HandleFunc("/users", u.getAll)
+	r.HandleFunc("/users/{username}", u.getOne)
+}