create existing logic

things/nest-typeorm/src/crud-base/crud-base.ts

@@ -34,15 +34,35 @@ export class CrudBase<
   }
 
   async create(ent: T) {
-    try {
-      const savedEntity = await this.repo.save(ent);
-      return new ReturnMessageDto(201, 'success', savedEntity);
-    } catch (e) {
-      this.error(
-        `Failed to create entity ${JSON.stringify(ent)}: ${e.toString()}`,
-      );
-      throw new BlankReturnMessageDto(500, 'internal error').toException();
-    }
+    const savedEnt = await this.repo.manager.transaction(async (mdb) => {
+      const repo = mdb.getRepository(this.entityClass);
+      if (ent.id != null) {
+        const existingEnt = await repo.findOne({
+          where: { id: ent.id },
+          take: 1,
+          select: ['id', 'isDeleted'],
+        });
+        if (existingEnt) {
+          if (existingEnt.isDeleted) {
+            await repo.delete({ id: ent.id });
+          } else {
+            throw new BlankReturnMessageDto(
+              404,
+              'already exists',
+            ).toException();
+          }
+        }
+      }
+      try {
+        return await repo.save(ent);
+      } catch (e) {
+        this.error(
+          `Failed to create entity ${JSON.stringify(ent)}: ${e.toString()}`,
+        );
+        throw new BlankReturnMessageDto(500, 'internal error').toException();
+      }
+    });
+    return new ReturnMessageDto(201, 'success', savedEnt);
   }
 
   protected get entityAliasName() {
@@ -76,7 +96,8 @@ export class CrudBase<
   async findOne(id: EntityId<T>) {
     const query = this.queryBuilder()
       .where(`${this.entityAliasName}.id = :id`, { id })
-      .andWhere(`${this.entityAliasName}.isDeleted = false`);
+      .andWhere(`${this.entityAliasName}.isDeleted = false`)
+      .take(1);
     this.applyRelationsToQuery(query);
     this.extraGetQuery(query);
     try {