ListRequestHandlerBase<TRow,TListRequest,TListResponse> class

namespace: Serenity.Services   assembly: Serenity.Net.Services

Abstract base class for list request handlers that share state and mode neutral helper methods between synchronous and asynchronous list request handlers.

public abstract class ListRequestHandlerBase<TRow, TListRequest, TListResponse> : 
    IListRequestHandler
    where TRow : class, IRow, new()
    where TListRequest : ListRequest
    where TListResponse : ListResponse<TRow>, new()

parameter	description
TRow	Entity type
TListRequest	List request type
TListResponse	List response type
context	Request context

Public Members

name	description
Cache { get; }	Gets the two level cache from the request context.
Connection { get; protected set; }	Gets the current connection.
Context { get; }	Gets the request context.
DistinctFields { get; protected set; }	Gets the list of distinct fields.
HandlerSettings { get; }	Gets the request handler settings (default / maximum page size), as returned by GetHandlerSettings.
Localizer { get; }	Gets the localizer from the request context.
Permissions { get; }	Gets the permission service from the request context.
Query { get; protected set; }	Gets the select query.
Request { get; protected set; }	Gets the request object.
Response { get; protected set; }	Gets the response object.
Row { get; protected set; }	Gets the entity used for querying / metadata lookup.
StateBag { get; }	A state bag for behaviors to preserve state among their methods. It will be cleared before each request, e.g. Process call.
User { get; }	Gets the current user from the request context.
GetDistinctFields()	Gets an array of distinct fields by checking Request.DistinctFields. It might be different than the passed list, if the list contains an invalid field or a field that is not allowed to be selected, like NotMapped and Never etc.
IgnoreEqualityFilter(…)	Adds the field to the list of ignored equality filters, so that having this field in the Request.EqualityFilter won't raise an exception

Protected Members

name	description
ListRequestHandlerBase(…)	Abstract base class for list request handlers that share state and mode neutral helper methods between synchronous and asynchronous list request handlers.
ignoredEqualityFilters	Set of ignored equality filter entries.
lookupAccessMode	True if the list handler is in lookup access mode, e.g. it only allows access to lookup fields.
rowsRead	Number of rows returned by the executed query before any post-processing (e.g. ProcessEntity dropping rows). Used to compute the More indicator based on the sentinel row rather than the filtered entity count.
virtual AddFieldContainsCriteria(…)	Applies a contains criteria based on containsText, id (if the contains text can be parsed to an integer ID), searchType and numericOnly parameters.
virtual AllowFilterField(…)	Returns true if the field can be used in a filter, based on its flags, minimum select level, read permission, and lookup access mode.
virtual AllowSelectField(…)	Returns true if the field should be allowed to be selected, based on is read permission, selectlevel.never flag, and lookup access mode
virtual AllowSortField(…)	Returns true if the field should be allowed to affect sort order.
virtual ApplyContainsText(…)	Applies contains text filter to the query
virtual ApplyCriteria(…)	Applies the Request.Criteria to the query if it is not null or empty, and replaced field references with their corresponding expressions by calling ReplaceFieldExpressions
virtual ApplyEqualityFilter(…)	Applies the Request.Equality filter to the query
virtual ApplyFieldContainsText(…)	Applies a field contains criteria to the query by calling AddFieldContainsCriteria
virtual ApplyFieldEqualityFilter(…)	Applies a field equality filter, e.g. one that is passed via Request.EqualityFilter to the query. It validates field flags like DenyFiltering and NotMapped, Never, and field read permissions to check if the field is allowed to be filtered.
virtual ApplyIncludeDeletedFilter(…)	Applies the not deleted filter to the query unless IncludeDeleted is true and the current user has the undelete permission for the row. Rows that do not use soft delete are always included.
virtual ApplyKeyOrder(…)	Applies the key order which is ID field (IIdRow)
virtual ApplySort(…)	Applies the Request.Sort order to the query. Sorts by GetNativeSort if no sort columns are passed, or the list is empty.
virtual ApplySortBy(…)	Applies a sort order to the query Fields with read permissions the user does not have are ignored.
virtual CreateQuery()	Creates a query instance with the dialect for current connection.
virtual GetBehaviors()	Gets the list of list behaviors.
virtual GetHandlerSettings()	Gets the request handler settings (default / maximum page size). The default implementation reads them from an IHasHandlerSettings capable request context, falling back to Default (no limits). Override to return different settings per request / entity, e.g. a limited page size for public access and unlimited for administrators (see With).
virtual GetNativeSort()	Gets the native sort order, which includes name field by default, unless the row has [SortOrder] attributes.
virtual GetPagingParams()	Validates the request paging values and builds the effective ListRequestPagingParams for the current request. Negative skip / take values are rejected as a validation error, while larger values are clamped to MaxPageSize so that the response can report the applied take. Paging limits are skipped when the request suppresses them (see SuppressPagingLimits). The returned params also carry ExcludeTotalCount, IncludeMore and ExcludeTotalCountByDefault, forcing ExcludeTotalCount when the query has distinct fields.
virtual GetQuickSearchFields(…)	Gets the list of quick search fields (QuickSearchAttribute) based on the containsField argument.
virtual GetUndeletePermission()	Gets the permission required to undelete records of the current row type, e.g. UndeletePermissionAttribute, falling back to DeletePermissionAttribute, ModifyPermissionAttribute and ReadPermissionAttribute.
IsEmptyEqualityFilterValue(…)	Checks if the equality filter value is empty. It returns true for null, empty string, or empty IEnumerable.
IsIncluded(…)	Returns true if field is included in IncludeColumns (2 methods)
abstract MapFieldExpression(…)	Maps a field using IListFieldMappingBehavior's if any
virtual ProcessEntity(…)	Can be overridden in a derived class to make some changes in a returned entity just before it gets added to the Response.Entities list.
virtual ReplaceFieldExpressions(…)	Replaces field references, e.g. property names and field name with their corresponding expression by using the CriteriaFieldExpressionReplacer
virtual SelectField(…)	Calls query.Select(field)
virtual SelectFields(…)	Calls query.Select(field) for all the fields without NotMapped, and if AllowSelectField and ShouldSelectField returns true.
virtual ShouldSelectField(…)	Returns true if the field should be selected, based on current ColumnSelection, field MinSelectLevelAttribute, the field being a not mapped (NotMappedAttribute) field, table field, or a view / expression field.
virtual ToCriteria(…)	Converts the field to criteria, using IListFieldMappingBehavior's if any
virtual ValidatePermissions()	Validates if the user is allowed to query this entity type by checking ReadPermissionAttribute and ServiceLookupPermissionAttribute if the request is in lookup access mode.

Exceptions

exception	condition
ArgumentNullException	context is null.

Remarks

Initializes a new instance of the class.

See Also

• interface IListRequestHandler
• interface IRow
• class ListRequest
• class ListResponse<T>
• Source: ListRequestHandlerBase.cs