feat: add song crd and tests (#80)

Co-authored-by: Zoe Roux <zoe.roux@sdg.moe>

back/prisma/migrations/20220924084638_/migration.sql

@@ -0,0 +1,61 @@
+-- CreateTable
+CREATE TABLE "User" (
+    "id" SERIAL NOT NULL,
+    "username" TEXT NOT NULL,
+    "password" TEXT NOT NULL,
+    "email" TEXT NOT NULL,
+
+    CONSTRAINT "User_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "Song" (
+    "id" SERIAL NOT NULL,
+    "name" TEXT NOT NULL,
+    "description" TEXT NOT NULL,
+    "artistId" INTEGER NOT NULL,
+    "albumId" INTEGER,
+    "genreId" INTEGER NOT NULL,
+    "difficulties" JSONB NOT NULL,
+
+    CONSTRAINT "Song_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "Genre" (
+    "id" SERIAL NOT NULL,
+    "name" TEXT NOT NULL,
+
+    CONSTRAINT "Genre_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "Artist" (
+    "id" SERIAL NOT NULL,
+    "name" TEXT NOT NULL,
+
+    CONSTRAINT "Artist_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "Album" (
+    "id" SERIAL NOT NULL,
+    "name" TEXT NOT NULL,
+
+    CONSTRAINT "Album_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "User_username_key" ON "User"("username");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "Song_name_key" ON "Song"("name");
+
+-- AddForeignKey
+ALTER TABLE "Song" ADD CONSTRAINT "Song_genreId_fkey" FOREIGN KEY ("genreId") REFERENCES "Genre"("id") ON DELETE RESTRICT ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "Song" ADD CONSTRAINT "Song_artistId_fkey" FOREIGN KEY ("artistId") REFERENCES "Artist"("id") ON DELETE RESTRICT ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "Song" ADD CONSTRAINT "Song_albumId_fkey" FOREIGN KEY ("albumId") REFERENCES "Album"("id") ON DELETE SET NULL ON UPDATE CASCADE;

back/prisma/migrations/20220926080922_/migration.sql

@@ -0,0 +1,8 @@
+-- DropForeignKey
+ALTER TABLE "Song" DROP CONSTRAINT "Song_genreId_fkey";
+
+-- AlterTable
+ALTER TABLE "Song" ALTER COLUMN "genreId" DROP NOT NULL;
+
+-- AddForeignKey
+ALTER TABLE "Song" ADD CONSTRAINT "Song_genreId_fkey" FOREIGN KEY ("genreId") REFERENCES "Genre"("id") ON DELETE SET NULL ON UPDATE CASCADE;

back/prisma/migrations/20220926082047_/migration.sql

@@ -0,0 +1,8 @@
+-- DropForeignKey
+ALTER TABLE "Song" DROP CONSTRAINT "Song_artistId_fkey";
+
+-- AlterTable
+ALTER TABLE "Song" ALTER COLUMN "artistId" DROP NOT NULL;
+
+-- AddForeignKey
+ALTER TABLE "Song" ADD CONSTRAINT "Song_artistId_fkey" FOREIGN KEY ("artistId") REFERENCES "Artist"("id") ON DELETE SET NULL ON UPDATE CASCADE;

back/prisma/migrations/20220926084154_/migration.sql

@@ -0,0 +1,8 @@
+/*
+  Warnings:
+
+  - You are about to drop the column `description` on the `Song` table. All the data in the column will be lost.
+
+*/
+-- AlterTable
+ALTER TABLE "Song" DROP COLUMN "description";

back/prisma/schema.prisma

@@ -17,6 +17,39 @@ model User {
   LessonHistory LessonHistory[]
 }
 
+model Song {
+  id           Int    @id @default(autoincrement())
+  name         String @unique
+  artistId     Int?
+  artist       Artist? @relation(fields: [artistId], references: [id])
+  albumId      Int?
+  album        Album? @relation(fields: [albumId], references: [id])
+  genreId      Int?
+  genre        Genre?  @relation(fields: [genreId], references: [id])
+  difficulties Json
+}
+
+model Genre {
+  id   Int    @id @default(autoincrement())
+  name String
+
+  Song Song[]
+}
+
+model Artist {
+  id   Int    @id @default(autoincrement())
+  name String
+
+  Song Song[]
+}
+
+model Album {
+  id   Int    @id @default(autoincrement())
+  name String
+
+  Song Song[]
+}
+
 model Lesson {
   id            Int             @id @default(autoincrement())
   name          String