feature of associating Warehouses: business restrictions and validation checks

Author: kopavel

src/main/java/com/fulfilment/application/monolith/rules/FulfillmentRuleRepository.java

@@ -6,10 +6,33 @@
 import io.quarkus.hibernate.orm.panache.PanacheRepository;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.transaction.Transactional;
+import jakarta.ws.rs.WebApplicationException;
+import jakarta.ws.rs.core.Response;
 
 @ApplicationScoped
 @Transactional
 public class FulfillmentRuleRepository implements PanacheRepository<DbFulfillmentRule> {
+  public void create(DbFulfillmentRule rule) {
+    if (find("warehouse = ?1 and store=?2 and product=?3",
+             rule.warehouse, rule.store, rule.product).count() > 0) {
+      throw new WebApplicationException("Rule already exists", Response.Status.CONFLICT);
+    }
+    if (countDistinctProductByWarehouse(rule.warehouse) >= 5) {
+      throw new WebApplicationException("Each `Warehouse` can store maximally 5 types of `Products`",
+                                        Response.Status.PRECONDITION_FAILED);
+    }
+    if (countDistinctStoresByWarehouse(rule.warehouse) >= 3) {
+      throw new WebApplicationException("Each `Store` can be fulfilled by a maximum of 3 different `Warehouses`",
+                                        Response.Status.PRECONDITION_FAILED);
+    }
+    if (countDistinctWarehousesByProductAndStore(rule.store, rule.product) >= 2) {
+      throw new WebApplicationException(
+        "Each `Product` can be fulfilled by a maximum of 2 different `Warehouses` per `Store`",
+        Response.Status.PRECONDITION_FAILED);
+    }
+    persist(rule);
+  }
+
   public long countDistinctStoresByWarehouse(DbWarehouse warehouse) {
     return find(
       "select count(distinct f.store.id) from " + DbFulfillmentRule.class.getSimpleName() + " f where f.warehouse = ?1",
@@ -19,7 +42,8 @@ public long countDistinctStoresByWarehouse(DbWarehouse warehouse) {
 
   public long countDistinctProductByWarehouse(DbWarehouse warehouse) {
     return find(
-      "select count(distinct f.product.id) from " + DbFulfillmentRule.class.getSimpleName() + " f where f.warehouse = ?1",
+      "select count(distinct f.product.id) from " + DbFulfillmentRule.class.getSimpleName() +
+        " f where f.warehouse = ?1",
       warehouse)
       .project(Long.class).firstResult();
 

src/main/java/com/fulfilment/application/monolith/rules/FulfillmentRuleResource.java

@@ -22,14 +22,14 @@ public List<FulfillmentRule> listAll() {
 
   @POST
   public FulfillmentRule create(FulfillmentRule rule) {
-    repository.persist(rule.toDb());
+    repository.create(rule.toDb());
     return rule;
   }
 
   @DELETE
   @Path("{id}")
   public void delete(@PathParam("id") Long id) {
-      DbFulfillmentRule rule = repository.findById(id);
+    DbFulfillmentRule rule = repository.findById(id);
     if (rule == null) {
       throw new WebApplicationException(404);
     }

src/main/resources/META-INF/resources/index.html

@@ -161,7 +161,9 @@
       }
 
       function _error(response) {
-        alert(response.data?.message || response.statusText);
+        // Показываем `error` из тела ответа, если оно есть
+        const msg = response.data?.error || response.statusText || 'Unknown error';
+        alert(msg);
       }
 
       function _clearForms() {