Files
2024-03-13 00:33:46 +01:00

239 lines
6.8 KiB
Transact-SQL

IF OBJECT_ID('auditlog.DialogPool') IS NOT NULL
DROP TABLE [auditlog].[DialogPool];
GO
CREATE TABLE [auditlog].[DialogPool] (
[FromService] SYSNAME NOT NULL,
[ToService] SYSNAME NOT NULL,
[OnContract] SYSNAME NOT NULL,
[Handle] UNIQUEIDENTIFIER NOT NULL,
[OwnerSPID] INT NOT NULL,
[CreationTime] DATETIME NOT NULL,
[SendCount] BIGINT NOT NULL,
CONSTRAINT [UQ_DialogPool_Handle] UNIQUE (Handle)
);
GO
IF OBJECT_ID('auditlog.usp_get_dialog') IS NOT NULL
DROP PROCEDURE [auditlog].[usp_get_dialog];
GO
CREATE PROCEDURE [auditlog].[usp_get_dialog]
@fromService SYSNAME,
@toService SYSNAME,
@onContract SYSNAME,
@dialogHandle UNIQUEIDENTIFIER OUTPUT,
@sendCount BIGINT OUTPUT
AS
BEGIN
SET NOCOUNT ON;
DECLARE @dialog TABLE (
[FromService] SYSNAME NOT NULL,
[ToService] SYSNAME NOT NULL,
[OnContract] SYSNAME NOT NULL,
[Handle] UNIQUEIDENTIFIER NOT NULL,
[OwnerSPID] INT NOT NULL,
[CreationTime] DATETIME NOT NULL,
[SendCount] BIGINT NOT NULL
);
-- Try to claim an unused dialog in DialogPool
-- READPAST option avoids blocking on locked dialogs.
BEGIN TRANSACTION;
DELETE FROM @dialog;
UPDATE TOP(1) [auditlog].[DialogPool] WITH(READPAST)
SET [OwnerSPID] = @@SPID
OUTPUT INSERTED.* INTO @dialog
WHERE [FromService] = @fromService
AND [ToService] = @toService
AND [OnContract] = @OnContract
AND [OwnerSPID] = -1;
IF @@ROWCOUNT > 0 BEGIN
SET @dialogHandle = (SELECT [Handle] FROM @dialog);
SET @sendCount = (SELECT [SendCount] FROM @dialog);
END
ELSE BEGIN
-- No free dialogs: need to create a new one
BEGIN DIALOG CONVERSATION @dialogHandle
FROM SERVICE @fromService
TO SERVICE @toService
ON CONTRACT @onContract
WITH ENCRYPTION = OFF;
INSERT INTO [auditlog].[DialogPool]
([FromService], [ToService], [OnContract], [Handle], [OwnerSPID], [CreationTime], [SendCount])
VALUES
(@fromService, @toService, @onContract, @dialogHandle, @@SPID, GETDATE(), 0);
SET @sendCount = 0;
END
COMMIT TRANSACTION;
END
GO
--------------------------------------------------------------------------
-- Free dialog procedure.
-- Return the dialog to the pool.
-- Inputs are dialog handle and updated send count.
--------------------------------------------------------------------------
IF OBJECT_ID('auditlog.usp_free_dialog') IS NOT NULL
DROP PROCEDURE [auditlog].[usp_free_dialog];
GO
CREATE PROCEDURE [auditlog].[usp_free_dialog]
@dialogHandle UNIQUEIDENTIFIER,
@sendCount BIGINT
AS
BEGIN
SET NOCOUNT ON;
DECLARE @rowcount INT;
DECLARE @string VARCHAR(50);
BEGIN TRANSACTION;
-- Release dialog by setting OwnerSPID to -1.
UPDATE [auditlog].[DialogPool] SET [OwnerSPID] = -1, [SendCount] = @sendCount
WHERE [Handle] = @dialogHandle;
SET @rowcount = @@ROWCOUNT;
IF @rowcount = 0 BEGIN
SET @string = (SELECT CAST( @dialogHandle AS VARCHAR(50)));
RAISERROR('usp_free_dialog: dialog %s not found in dialog pool', 16, 1, @string) WITH LOG;
END
ELSE IF @rowcount > 1 BEGIN
SET @string = (SELECT CAST( @dialogHandle AS VARCHAR(50)));
RAISERROR('usp_free_dialog: duplicate dialog %s found in dialog pool', 16, 1, @string) WITH LOG;
END
COMMIT TRANSACTION;
END
GO
IF OBJECT_ID('auditlog.usp_delete_dialog') IS NOT NULL
DROP PROCEDURE [auditlog].[usp_delete_dialog];
GO
CREATE PROCEDURE [auditlog].[usp_delete_dialog]
@dialogHandle UNIQUEIDENTIFIER
AS
BEGIN
SET NOCOUNT ON;
BEGIN TRY
BEGIN TRANSACTION;
DELETE [DialogPool] WHERE Handle = @dialogHandle;
COMMIT TRANSACTION;
END TRY
BEGIN CATCH
-- Rollback any active or uncommittable transactions before
-- inserting information in the ErrorLog
IF @@TRANCOUNT > 0 BEGIN
ROLLBACK TRANSACTION;
END
EXECUTE [auditlog].[uspLogError];
END CATCH;
END
GO
IF OBJECT_ID('auditlog.usp_send') IS NOT NULL
DROP PROCEDURE [auditlog].[usp_send];
GO
CREATE PROCEDURE [auditlog].[usp_send]
@fromService SYSNAME,
@toService SYSNAME,
@onContract SYSNAME,
@messageType SYSNAME,
@messageBody NVARCHAR(MAX)
WITH EXECUTE AS 'Kreta_tech_user'
AS
BEGIN
SET NOCOUNT ON;
DECLARE @dialogHandle UNIQUEIDENTIFIER;
DECLARE @sendCount BIGINT;
DECLARE @counter INT;
DECLARE @error INT;
SET @counter = 1;
BEGIN TRANSACTION;
-- message validation check, preventing poison message at the target service validation
-- target service validates WELL_FORMED_XML types, so it is best to prevent it at here
IF EXISTS (SELECT 1 FROM sys.[service_message_types] WHERE [name] = @messageType AND [validation] = 'X')
AND (TRY_CONVERT(xml, @messageBody) IS NOT NULL)
BEGIN
SET @messageBody = CAST(TRY_CONVERT(xml, @messageBody) AS nvarchar(max))
END
ELSE BEGIN
INSERT INTO [auditlog].[AuditServiceFailedItems] ([conversation_handle], [message_body])
VALUES ('00000000-0000-0000-0000-000000000000', @messageBody)
COMMIT TRANSACTION;
RAISERROR('XML validation failure before sending. Check [auditlog].[AuditServiceFailedItems] for failed message.', 16,1) WITH LOG;
END
-- Will need a loop to retry in case the dialog is
-- in a state that does not allow transmission
WHILE (1=1) BEGIN
-- Claim a dialog from the dialog pool.
-- A new one will be created if none are available.
EXEC [auditlog].[usp_get_dialog] @fromService, @toService, @onContract, @dialogHandle OUTPUT, @sendCount OUTPUT;
-- Attempt to SEND on the dialog
IF (@messageBody IS NOT NULL) BEGIN
-- If the @messageBody is not null it must be sent explicitly
SEND ON CONVERSATION @dialogHandle MESSAGE TYPE @messageType (@messageBody);
END
ELSE BEGIN
-- Messages with no body must *not* specify the body,
-- cannot send a NULL value argument
SEND ON CONVERSATION @dialogHandle MESSAGE TYPE @messageType;
END
SET @error = @@ERROR;
IF @error = 0 BEGIN
-- Successful send, increment count and exit the loop
SET @sendCount = @sendCount + 1;
BREAK;
END
SET @counter = @counter + 1;
IF @counter > 10 BEGIN
-- We failed 10 times in a row, something must be broken
RAISERROR('Failed to SEND on a conversation for more than 10 times. Error %i.', 16, 1, @error) WITH LOG;
BREAK;
END
-- Delete the associated dialog from the table and try again
EXEC [auditlog].[usp_delete_dialog] @dialogHandle;
SELECT @dialogHandle = NULL;
END
-- "Criterion" for dialog pool removal is send count > 1000.
-- Modify to suit application.
-- When deleting also inform the target to end the dialog.
IF @sendCount > 1000 BEGIN
EXEC [auditlog].[usp_delete_dialog] @dialogHandle ;
SEND ON CONVERSATION @dialogHandle MESSAGE TYPE [EndOfStream];
END
ELSE BEGIN
-- Free the dialog.
EXEC [auditlog].[usp_free_dialog] @dialogHandle, @sendCount;
END
COMMIT TRANSACTION;
END
GO