/// <summary>
        /// Verifies the extension rule.
        /// </summary>
        /// <param name="context">The Interop service context</param>
        /// <param name="info">out parameter to return violation information when rule does not pass</param>
        /// <returns>true if rule passes; false otherwise</returns>
        public override bool?Verify(ServiceContext context, out ExtensionRuleViolationInfo info)
        {
            if (context == null)
            {
                throw new ArgumentNullException("context");
            }

            bool?passed = null;

            info = null;
            ServiceStatus serviceStatus    = ServiceStatus.GetInstance();
            DataFactory   dFactory         = DataFactory.Instance();
            var           detail           = new ExtensionRuleResultDetail(this.Name, serviceStatus.RootURL, HttpMethod.Post, string.Empty);
            string        updateUrl        = serviceStatus.RootURL;
            List <string> keyPropertyTypes = new List <string>()
            {
                "Edm.Int32", "Edm.Int16", "Edm.Int64", "Edm.Guid", "Edm.String"
            };
            List <string> norPropertyTypes = new List <string>()
            {
                "Edm.String"
            };
            List <EntityTypeElement> entityTypeElements = MetadataHelper.GetEntityTypes(serviceStatus.MetadataDocument, 1, keyPropertyTypes, null, NavigationRoughType.None).ToList();

            if (null == entityTypeElements || 0 == entityTypeElements.Count)
            {
                detail.ErrorMessage = "To verify this rule it expects an entity type with Int32/Int64/Int16/Guid/String key property and a string type normal property, but there is no this entity type in metadata so can not verify this rule.";
                info = new ExtensionRuleViolationInfo(new Uri(serviceStatus.RootURL), serviceStatus.ServiceDocument, detail);

                return(passed);
            }

            EntityTypeElement entityType = null;

            List <string> collectionPropNames = new List <string>();

            foreach (var en in entityTypeElements)
            {
                if (MetadataHelper.HasEntityCollectionProp(serviceStatus.MetadataDocument, en.EntityTypeShortName, context, out collectionPropNames))
                {
                    entityType = en;
                    break;
                }
            }

            if (collectionPropNames != null && !collectionPropNames.Any())
            {
                detail.ErrorMessage = "To verify this rule it is expected that an entity type has collection type normal property, but there is no this entity type in metadata so can not verify this rule.";
                info = new ExtensionRuleViolationInfo(new Uri(serviceStatus.RootURL), serviceStatus.ServiceDocument, detail);

                return(passed);
            }

            string collectionPropName = collectionPropNames.First();

            string entitySetUrl = entityType.EntitySetName.MapEntitySetNameToEntitySetURL();

            updateUrl = serviceStatus.RootURL.TrimEnd('/') + @"/" + entitySetUrl;
            if (string.IsNullOrEmpty(entitySetUrl))
            {
                detail.ErrorMessage = string.Format("Cannot find the entity-set URL which is matched with {0}", entityType.EntityTypeShortName);
                info = new ExtensionRuleViolationInfo(new Uri(serviceStatus.RootURL), serviceStatus.ServiceDocument, detail);

                return(passed);
            }

            string url             = serviceStatus.RootURL.TrimEnd('/') + @"/" + entitySetUrl;
            var    additionalInfos = new List <AdditionalInfo>();
            var    reqData         = dFactory.ConstructInsertedEntityData(entityType.EntitySetName, entityType.EntityTypeShortName, null, out additionalInfos);
            string reqDataStr      = reqData.ToString();
            bool   isMediaType     = !string.IsNullOrEmpty(additionalInfos.Last().ODataMediaEtag);
            var    resp            = WebHelper.CreateEntity(url, context.RequestHeaders, reqData, isMediaType, ref additionalInfos);

            detail = new ExtensionRuleResultDetail(this.Name, url, HttpMethod.Post, string.Empty, resp, string.Empty, reqDataStr);
            if (HttpStatusCode.Created == resp.StatusCode)
            {
                string entityId = additionalInfos.Last().EntityId;
                updateUrl = entityId.TrimEnd('/') + "/" + collectionPropName;
                bool hasEtag = additionalInfos.Last().HasEtag;
                resp   = WebHelper.GetPropertyValue(updateUrl);
                detail = new ExtensionRuleResultDetail(this.Name, entityId, HttpMethod.Get, string.Empty, resp);
                if (HttpStatusCode.OK == resp.StatusCode)
                {
                    JProperty complexPropContent = dFactory.ConstructPropertyData(entityType.EntitySetName, entityType.EntityTypeShortName, collectionPropName);
                    resp   = WebHelper.UpdateCollectionProperty(updateUrl, context.RequestHeaders, complexPropContent, hasEtag);
                    detail = new ExtensionRuleResultDetail(this.Name, url, HttpMethod.Put, string.Empty, resp, string.Empty, reqDataStr);
                    if (HttpStatusCode.NoContent == resp.StatusCode)
                    {
                        resp   = WebHelper.GetPropertyValue(updateUrl);
                        detail = new ExtensionRuleResultDetail(this.Name, entityId, HttpMethod.Get, string.Empty, resp, string.Empty, reqDataStr);

                        if (HttpStatusCode.OK == resp.StatusCode)
                        {
                            JObject value;
                            resp.ResponsePayload.TryToJObject(out value);

                            bool updated = true;

                            if (value != null && value.Type == JTokenType.Object)
                            {
                                foreach (var prop in value.Children <JProperty>())
                                {
                                    if (!prop.Value.ToString().Equals(Constants.UpdateData))
                                    {
                                        passed = false;
                                        detail.ErrorMessage = string.Format("The collection property in request fails in HTTP put updating.");
                                        break;
                                    }
                                }

                                if (updated)
                                {
                                    passed = true;
                                }
                            }
                        }
                        else
                        {
                            passed = false;
                            detail.ErrorMessage = "Can not get the updated entity.";
                        }
                    }
                    else
                    {
                        passed = false;
                        detail.ErrorMessage = "HTTP put the collection property failed.";
                    }
                }
                else
                {
                    detail.ErrorMessage = "Can not get the created entity from above URI.";
                }

                // Restore the service.
                var resps = WebHelper.DeleteEntities(context.RequestHeaders, additionalInfos);
            }
            else
            {
                detail.ErrorMessage = "Created the new entity failed for above URI.";
            }

            var details = new List <ExtensionRuleResultDetail>()
            {
                detail
            };

            info = new ExtensionRuleViolationInfo(new Uri(updateUrl), serviceStatus.ServiceDocument, details);

            return(passed);
        }