SSB(SQLservice Service Broker) 入门实例

前两天用了 MSsql里的 SSB委托机制，做了一个消息分发的小功能，在这里简单跟大家分享一下方法跟实例.

step 1：perpar database & data

use master
go
Create database Inventory
go
use Inventory
go
Create table inventory
(
    TitleId nvarchar(6) not null,
    Quantity int not null,
    primary key (TitleId,Quantity)
);
go

insert inventory values ('pc1001',100);
insert inventory values ('pc1002',200);
insert inventory values ('pc1003',300);
insert inventory values ('pc1004',400);

 step 2: 创建整个SSB的基础框架.

 首先创建信息类型

Create Message Type [//mark/v10/types/inventory]
Create Message Type [//mark/v10/types/inventoryresponse]

 创建合约 

create contract [//mark/v10/contracts/inventorycontract]
(
    [//mark/v10/types/inventory] sent by initiator,
    [//mark/v10/types/inventoryresponse] sent by target
);

创建队列与服务

create queue [inventory client queue];
create service [//mark/v10/services/inventory client]
    on queue [inventory client queue]
    
    go
    --create inventory service
    create queue [inventory queue];
    create service [//mark/v10/services/inventory]
    on queue [inventory queue]
    (
        [//mark/v10/contracts/inventorycontract]
    );

step 3：发送消息到消息队列中

use Inventory
go
--send message
begin transaction
    declare @dialog_id uniqueidentifier
    begin dialog conversation @dialog_id
        from service [//mark/v10/services/inventory client]
        to service '//mark/v10/services/inventory'
        on contract [//mark/v10/contracts/inventorycontract]
        with encryption = off;
        send on conversation @dialog_id message type [//mark/v10/types/inventory]
        (
        '<InventoryUpdate>
        <TitleId>pc1001</TitleId>
        <Quantity>102</Quantity>
        </InventoryUpdate>'    
        );
        commit transaction;

发送成功后，可以查询 inventory_queue

select conversation_handle, cast(message_body as xml) as conversation_body from [Inventory queue] 

这里只是查询了两列。

   其中conversation_body 就是 我们发出的信息了。

 setp 4: 从 inventory queue 中获取信息并更新数据

use inventory
go
begin transaction
    declare @dialog_id uniqueidentifier
    declare @message_body xml
    declare @amount int;
    declare @title nvarchar(128);
    
    receive
        @dialog_id = conversation_handle,
        @message_body = message_body 
    from [dbo].[Inventory queue]
    
    print 'handle is' + cast(@dialog_id as nvarchar(90))
    print 'message body is' + cast(@message_body as  nvarchar(max) )
    if(@dialog_id is not null)
    begin 
        set @amount = @message_body.value('(/InventoryUpdate/Quantity)[1]','int');
        set @title = @message_body.value('(/InventoryUpdate/TitleId)[1]','nvarchar(100)');
        print 'a:'+cast(@amount as nvarchar(100))
        print 'b:'+@title;
        
        Update inventory set Quantity = @amount where TitleId = @title;
        end
        end conversation @dialog_id;
    commit transaction;

 操作成功后再去查询inventory queue的表 犹豫里面的数据已经被receive 出来 就为空了。

数据同时被更新了 

step 5: 接下来做个自动监听功能，只要有信息发送到队列，相关队列，就可以自动执行功能.

首先建立个存储过程，（把receive 中的那段代码拿过来就可以了）

use Inventory
go
--create procedure to receive message and update table
create proc InventoryProc as

begin transaction
    declare @dialog_id uniqueidentifier
    declare @message_body xml
    declare @amount int;
    declare @title nvarchar(128);
    
    waitfor(
    receive
        @dialog_id = conversation_handle,
        @message_body = message_body 
    from [dbo].[Inventory queue]),timeout 5000;
    
    print 'handle is' + cast(@dialog_id as nvarchar(90))
    print 'message body is' + cast(@message_body as  nvarchar(max) )
    if(@dialog_id is not null)
    begin 
        set @amount = @message_body.value('(/InventoryUpdate/Quantity)[1]','int');
        set @title = @message_body.value('(/InventoryUpdate/TitleId)[1]','nvarchar(100)');
        print 'a:'+cast(@amount as nvarchar(100))
        print 'b:'+@title;
        
        Update inventory set Quantity = @amount where TitleId = @title;
        end
        end conversation @dialog_id;
    commit transaction;
    go

队列监听

   alter queue [inventory queue]
        with activation(
            status = on,
            procedure_name=    InventoryProc,
            max_queue_readers=2,
            execute as self
        );
        
        go

 完成后，只要发送队列信息后，就可以了

PS： 我们定义了 两个队列 还有个 inventory client queue

这个队列保存的是成功或者error 提示。用receive 方法也可以提取出来。

select message_type_name from [Inventory client queue]

以上的 message type  service 等信息   如图所示，都在这里.

以上是SSB的入门实例，以后会再写一篇实际应用上的（以上的sql code 都是纯手工输入，可能还存在错误（虽然校验了两遍）,如果发生错误，对不起大家了。）