Enn Õunapuu

Transcription

1 Asünkroonsed teenused Enn Õunapuu

2 Määrang Asynchronous processing enables methods to return immediately without blocking on the calling thread. Consumers request asynchronous processing when initializing a data source object or when opening or populating a rowset. The consumer must explicitly request asynchronous processing. Otherwise, the provider can perform asynchronous operations in the background but must behave synchronously, blocking if necessary, until the underlying asynchronous operation completes.

3 Miks asünkroonne 1. Ei blokeeri rakenduse 2. Hoiab ressursse kokku

4 Messagging

5 Asynchronous messaging Asynchronous messaging is fundamentally a pragmatic reaction to the problems of distributed systems. Sending a message does not require both systems to be up and ready at the same time. Furthermore, thinking about the communication in an asynchronous manner forces developers to recognize that working with a remote application is slower, which encourages design of components with high cohesion (lots of work locally) and low adhesion (selective work remotely).

6 Basic Messaging Concepts Channels Messaging applications transmit data through a Message Channel, a virtual pipe that connects a sender to a receiver. Messages A Message is an atomic packet of data that can be transmitted on a channel. Multi-step delivery A Pipes and Filters architecture describes how multiple processing steps can be chained together using channels. Routing In a large enterprise with numerous applications and channels to connect them, a message may have to go through several channels to reach its final destination. Transformation Various applications may not agree on the format for the same conceptual data; the sender formats the message one way, yet the receiver expects it to be formatted another way. Endpoints This bridge code is a set of coordinated Message Endpoints that enable the application to send and receive messages.

7 Message Channel

8 Message

9 Pipes and filters

10 Message router

11 Message translator

12 Message endpoint

13 Enterprise integration Patterns

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16 Event Driven Messaging Service A requests that it be set up as a subscriber to the event it is interested in by interacting with an event manager. Once the event occurs, Service B forwards the details to the event manager which, in turn, notifies Service A (and all other subscribers) via a one-way, asynchronous data transfer. Note that in this case, Service A also receives the event information earlier because the event details can be transmitted as soon as they're available.

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19 Complex event processing

20 Enterprise 1.0 ( 60s 80s) Enterprise 2.0 ( 80s 2000) Enterprise 3.0 ( ) Data Processing Client Server Predictive Building Block Mainframe Database ESB Software 2-Tier 3-Tier N-Tier Velocity Batch Online Event Driven Interactions 000 s 000,000 s 000,000,000,000 s 20

21 Half Life of Data Enterprise 1.0 ( 60s 80s) Enterprise 2.0 ( 80s 2000) Enterprise 3.0 Amount of Data ( ) Time to React Data Processing Client Server Predictive Building Block Mainframe Database ESB Software 2-Tier 3-Tier N-Tier Velocity Batch Online Event Driven Interactions 000,000 s 000,000,000 s 000,000,000,000 s 21

22 The Data Advantage Events Enterprise 3.0 Threats & Opportunities Transactions Enterprise

23 Potential Business Value CEP enables More Effective Decisions Business Automation Enables Fast Response Business Event Effective Real-time Decisions Dynamic Business Conditions Point of Transaction Response to Dynamic Conditions Result Measured Root Cause Determined Corrective Decision Made Action Taken Action time 23

24 Velocity drives need for Event Processing Business Cycle-Time Improvements Perform Trading Analytics Airline Operations 30 minutes 20 minutes 5 seconds 30 seconds Handle Call Center Inquiries Track Financial/Risk Position 1 day 8 hours 5 minutes 10 seconds Supply Chain Updates Document Transfer Phone/Service Activation Refresh Data Warehouse Settle Trade/Transaction Build-to-Order Product 1 day 3 days 3 days 1 month 5 days 6 weeks 15 minutes Mail express fax 20 seconds 1 hour 1 hour 1 day 1 day Source: Gartner 24

25 Demo

26 public bool SavetoMSMQ(string XMLDoc) { Boolean edu = true; // check if queue exists, if not create it MessageQueue msmq = null; if (!MessageQueue.Exists(ConfigurationManager.AppSettings["queueName"])) { msmq = MessageQueue.Create(ConfigurationManager.AppSettings["queueName"]); } else { msmq = new MessageQueue(ConfigurationManager.AppSettings["queueName"]); } try { msmq.send(xmldoc); } catch (Exception ee) { edu = false; } finally { msmq.close(); } return edu; }

27 <appsettings> <!-- use appsetting to configure MSMQ queue name --> <add key="queuename" value=".\private$\invoicequeue"/> </appsettings>

28 protected void Button1_Click(object sender, EventArgs e) { Stream thestream = FileUpload1.PostedFile.InputStream; StreamReader reader = new StreamReader(theStream); string text = reader.readtoend(); MSMQ client = new MSMQ(); client.savetomsmqasync(text); Label1.Text = "kirjutatud MSMQ-sse FILE:" + FileUpload1.FileName; }

29 Jõudu!!!