create preorder sample api

main.go

@@ -1,50 +1,38 @@
 package main
 
 import (
+	"fmt"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
 )
 
-// album represents data about a record album.
-type album struct {
-	ID     string  `json:"id"`
-	Title  string  `json:"title"`
-	Artist string  `json:"artist"`
-	Price  float64 `json:"price"`
-}
-
-// albums slice to seed record album data.
-var albums = []album{
-	{ID: "1", Title: "Blue Train", Artist: "John Coltrane", Price: 56.99},
-	{ID: "2", Title: "Jeru", Artist: "Gerry Mulligan", Price: 17.99},
-	{ID: "3", Title: "Sarah Vaughan and Clifford Brown", Artist: "Sarah Vaughan", Price: 39.99},
-}
-
-// getAlbums responds with the list of all albums as JSON.
-func getAlbums(c *gin.Context) {
-	c.IndentedJSON(http.StatusOK, albums)
+func generatePreorderRelation(set []int) map[string]bool {
+	preorderRelation := make(map[string]bool)
+	for _, element := range set {
+		preorderRelation[fmt.Sprintf("[%d,%d]", element, element)] = true
+		for _, otherElement := range set {
+			if element <= otherElement {
+				preorderRelation[fmt.Sprintf("[%d,%d]", element, otherElement)] = true
+			}
+		}
+	}
+	return preorderRelation
 }
 
-// postAlbums adds an album from JSON received in the request body.
-func postAlbums(c *gin.Context) {
-	var newAlbum album
+func main() {
+	r := gin.Default()
 
-	// Call BindJSON to bind the received JSON to
-	// newAlbum.
-	if err := c.BindJSON(&newAlbum); err != nil {
+	r.POST("/preorder", func(c *gin.Context) {
+		var set []int
+		if err := c.BindJSON(&set); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": "Invalid request body"})
 			return
-	}
+		}
 
-	// Add the new album to the slice.
-	albums = append(albums, newAlbum)
-	c.IndentedJSON(http.StatusCreated, newAlbum)
-}
+		preorderRelation := generatePreorderRelation(set)
+		c.JSON(http.StatusOK, preorderRelation)
+	})
 
-func main() {
-	router := gin.Default()
-	router.GET("/albums", getAlbums)
-	router.POST("/albums", postAlbums)
-
-	router.Run("localhost:8080")
-}
+	r.Run()
+}

preorder/any_preorder/main_test.go

@@ -5,7 +5,7 @@ import (
 	"testing"
 )
 
-func TestgenerateAnyPreorderRelationInts(t *testing.T) {
+func TestGenerateAnyPreorderRelationInts(t *testing.T) {
 	set := []interface{}{1, 2, 3}
 	expected := map[[2]interface{}]bool{
 		{1, 1}: true, {1, 2}: true, {1, 3}: true,
@@ -19,7 +19,7 @@ func TestgenerateAnyPreorderRelationInts(t *testing.T) {
 	}
 }
 
-func TestgenerateAnyPreorderRelationStrings(t *testing.T) {
+func TestGenerateAnyPreorderRelationStrings(t *testing.T) {
 	set := []interface{}{"apple", "banana", "cherry"}
 	expected := map[[2]interface{}]bool{
 		{"apple", "apple"}: true, {"apple", "banana"}: true, {"apple", "cherry"}: true,