Add basic problem service (#16)

* Add problem mapper

* Add problem option search test

* Move service code

* Problem router & service

Makefile

@@ -5,7 +5,7 @@ build:
 	@echo "Building on $(OS)"
 	go mod tidy
 	go build -o bin/migrate_db migration/migrate_db.go
-	go build -o bin/user_service user-service/application.go
+	go build -o bin/service service/application.go
 
 .PHONY: clear-db
 clear-db:
@@ -29,7 +29,7 @@ test: build check setup-db
 
 .PHONY: run
 run: build check setup-db
-	./bin/user_service
+	./bin/service
 
 .PHONY: help
 help:

packages/mapper/problem.go

@@ -1 +1,103 @@
 package mapper
+
+import (
+	"github.com/OJ-lab/oj-lab-services/packages/application"
+	"github.com/OJ-lab/oj-lab-services/packages/model"
+)
+
+func CreateProblem(problem model.Problem) error {
+	db := application.GetDefaultDB()
+	return db.Create(&problem).Error
+}
+
+func GetProblem(slug string) (model.Problem, error) {
+	db := application.GetDefaultDB()
+	db_problem := model.Problem{}
+	err := db.Model(&model.Problem{}).Preload("Tags").Where("Slug = ?", slug).First(&db_problem).Error
+	return db_problem, err
+}
+
+func DeleteProblem(problem model.Problem) error {
+	db := application.GetDefaultDB()
+	return db.Delete(&model.Problem{Slug: problem.Slug}).Error
+}
+
+func UpdateProblem(problem model.Problem) error {
+	db := application.GetDefaultDB()
+	return db.Model(&model.Problem{Slug: problem.Slug}).Updates(problem).Error
+}
+
+type GetProblemOptions struct {
+	Slug   string
+	Title  string
+	Tags   []*model.AlgorithmTag
+	Offset *int
+	Limit  *int
+}
+
+func CountProblemByOptions(options GetProblemOptions) (int64, error) {
+	db := application.GetDefaultDB()
+	var count int64
+
+	tagsList := []string{}
+	for _, tag := range options.Tags {
+		tagsList = append(tagsList, tag.Slug)
+	}
+
+	tx := db.
+		Model(&model.Problem{}).
+		Joins("JOIN problem_algorithm_tags ON problem_algorithm_tags.problem_slug = problems.slug").
+		Where("problem_algorithm_tags.algorithm_tag_slug in ?", tagsList).
+		Or("Slug = ?", options.Slug).
+		Or("Title = ?", options.Title).
+		Distinct().
+		Preload("Tags")
+
+	err := tx.Count(&count).Error
+
+	return count, err
+}
+
+func GetProblemByOptions(options GetProblemOptions) ([]model.Problem, int64, error) {
+	total, err := CountProblemByOptions(options)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	db := application.GetDefaultDB()
+	db_problems := []model.Problem{}
+	tagsList := []string{}
+	for _, tag := range options.Tags {
+		tagsList = append(tagsList, tag.Slug)
+	}
+	tx := db.
+		Model(&model.Problem{}).
+		Joins("JOIN problem_algorithm_tags ON problem_algorithm_tags.problem_slug = problems.slug").
+		Where("problem_algorithm_tags.algorithm_tag_slug in ?", tagsList).
+		Or("Slug = ?", options.Slug).
+		Or("Title = ?", options.Title).
+		Distinct().
+		Preload("Tags")
+
+	if options.Offset != nil {
+		tx = tx.Offset(*options.Offset)
+	}
+	if options.Limit != nil {
+		tx = tx.Limit(*options.Limit)
+	}
+
+	err = tx.Find(&db_problems).Error
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return db_problems, total, nil
+}
+
+func GetTagsList(problem model.Problem) []string {
+	tagsList := []string{}
+	for _, tag := range problem.Tags {
+		tagsList = append(tagsList, tag.Slug)
+	}
+	return tagsList
+}

packages/mapper/problem_test.go

@@ -0,0 +1,54 @@
+package mapper
+
+import (
+	"encoding/json"
+	"fmt"
+	"testing"
+
+	"github.com/OJ-lab/oj-lab-services/packages/model"
+)
+
+func TestProblemMapper(t *testing.T) {
+	problem := model.Problem{
+		Slug:        "a+b-problem",
+		Title:       "A+B Problem",
+		Description: "Given two integer A and B, please output the answer of A+B.",
+		Tags:        []*model.AlgorithmTag{{Slug: "tag1"}, {Slug: "tag2"}},
+	}
+	err := CreateProblem(problem)
+	if err != nil {
+		t.Error(err)
+	}
+
+	dbProblem, err := GetProblem(problem.Slug)
+	if err != nil {
+		t.Error(err)
+	}
+
+	problemJson, err := json.MarshalIndent(dbProblem, "", "\t")
+	if err != nil {
+		t.Error(err)
+	}
+	fmt.Printf("%+v\n", string(problemJson))
+
+	problemOption := GetProblemOptions{
+		Slug:  "",
+		Title: "",
+		Tags:  []*model.AlgorithmTag{{Slug: "tag1"}},
+	}
+
+	dbProblems, problemCount, err := GetProblemByOptions(problemOption)
+	if err != nil {
+		t.Error(err)
+	}
+	fmt.Printf("problemCount: %d\n", problemCount)
+	if problemCount != 1 {
+		t.Error("problemCount should be 1")
+	}
+
+	problemsJson, err := json.MarshalIndent(dbProblems, "", "\t")
+	if err != nil {
+		t.Error(err)
+	}
+	fmt.Printf("%+v\n", string(problemsJson))
+}

packages/model/problem.go

@@ -4,7 +4,7 @@ type Problem struct {
 	MetaFields
 	Slug        string          `gorm:"primaryKey"`
 	Title       string          `gorm:"not null"`
-	Discription string          `gorm:"not null"`
+	Description string          `gorm:"not null"`
 	Tags        []*AlgorithmTag `gorm:"many2many:problem_algorithm_tags;"`
 }
 

user-service/application.go → service/application.go

@@ -2,7 +2,7 @@ package main
 
 import (
 	"github.com/OJ-lab/oj-lab-services/packages/application"
-	"github.com/OJ-lab/oj-lab-services/user-service/router"
+	"github.com/OJ-lab/oj-lab-services/service/router"
 	"github.com/gin-gonic/gin"
 )
 
@@ -25,6 +25,7 @@ func main() {
 	r := gin.Default()
 	gin.SetMode(serviceMode)
 	router.SetupUserRouter(r)
+	router.SetupProblemRoute(r)
 
 	err := r.Run(servicePort)
 	if err != nil {

service/problem/problem.go

@@ -0,0 +1,23 @@
+package problem
+
+import (
+	"github.com/OJ-lab/oj-lab-services/packages/mapper"
+	"github.com/OJ-lab/oj-lab-services/packages/utils"
+	"github.com/gin-gonic/gin"
+)
+
+func GetProblemInfo(c *gin.Context) {
+	slug := c.Param("slug")
+	problem, err := mapper.GetProblem(slug)
+	if err != nil {
+		utils.ApplyError(c, err)
+		return
+	}
+
+	c.JSON(200, gin.H{
+		"slug":        problem.Slug,
+		"title":       problem.Title,
+		"description": problem.Description,
+		"tags":        mapper.GetTagsList(problem),
+	})
+}

service/router/setup.go

@@ -0,0 +1,27 @@
+package router
+
+import (
+	"net/http"
+
+	"github.com/OJ-lab/oj-lab-services/service/problem"
+	"github.com/gin-gonic/gin"
+)
+
+func SetupUserRouter(r *gin.Engine) {
+	g := r.Group("/api/user")
+	{
+		g.GET("/health", func(c *gin.Context) {
+			c.String(http.StatusOK, "Hello, this is user service")
+		})
+	}
+}
+
+func SetupProblemRoute(r *gin.Engine) {
+	g := r.Group("/api/v1/problem")
+	{
+		g.GET("/health", func(c *gin.Context) {
+			c.String(http.StatusOK, "Hello, this is problem service")
+		})
+		g.GET("/:slug", problem.GetProblemInfo)
+	}
+}