Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 1 Enterprise Service Bus Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Atomic Patterns

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 3 Operating System for Distributed Program Design Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Enterprise Service Bus

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 4 Logosworld An ESB takes the role of an operating system across distributed independent computers SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com ESB is a software architecture model to support pattern based communication

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 5 Logosworld The concept is based on the principle that every two components communicate via a common, publically accessible communication channel. SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com ESB is modeled analogous to the microprocessor Bus architecture model.

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 6 Communication exclusively via the bus Logosworld The concept is based on the principle that every two components do only communicate via a common, publically accessible communication channel - the bus. SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com � Bus

Logosworld Enterprise Architects Education Audit Realignment Rescue 7 Duties of an Enterprise Service Bus • ESB is a large collection of public services • Allows dynamic plugging of services Manage service invocation • Assigns tasks to available servers for execution Monitor/control collisions • Controls message traffic and guarantee accident free delivery Host Commodity Services • Hosts public services that are convenient for other services Protocol Conversion Scripting and rules Logosworld Coaching Message Queue • Provides centralized and harmonic protocol conversion • Allows easy automation of tasks • Allows staging of messages to avoid data loss SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Manage service invocation Assigns tasks to available servers for execution Host Commodity Services Hosts public services that are convenient and needed by other services Monitor and control collisions Controls message traffic and guarantee accident free delivery Protocol Conversion Provides centralized and harmonic protocol conversion Scripting automatic tasks Allows easy automation of tasks and embed rules engines Queue Message Allows staging and automatic forwarding of messages to avoid loss Architecture

Logosworld Enterprise Architects Education Coaching Realignment Rescue 8 Core Elements of ESB • An ESB is extensible by services and other ESB • Other basic services can be added at any time Service Plugs • Add and remove services Message Queue • Buffer messages until they can be processed Process Director • Control the process flow Message Router • Dynamically decide the sequence of service execution Process Monitor • Monitor the behavior of the processes Exception Handler Logosworld Audit Adapter Engine • Handle errors and exceptions dynamically • Interface to outside orbit SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Service Plugs Add and remove services Message Queue Buffer messages until they can be processed Process Director Control the process flow Message Router Dynamically decide the sequence of service execution Process Monitor the behavior of the processes Exception Handler Handle errors and exceptions dynamically Adapter Engine Interface to outside orbit Architecture

Logosworld Enterprise Architects All communication via message queues Architecture Education Coaching Audit Realignment Rescue 9 Common Processing Pattern Data is delivered via an adapter to queue Q Business process is invoked by the ESB Q Q Q Process Adapter Transform Canonical Result converted back and delivered by adapter Internal Pipes Adapter Transform Canonical Harmonization Section Interface Section to Outside Orbit Adapter Q Transform Q Process Q Transform Q Adapter Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Message is transformed to canonical format

Logosworld Enterprise Architects Education Coaching Realignment Audit Rescue 10 Communication via Bus Devices Adapter connector Logic Transport Control Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Communicati on has three layers Logic, Data, Control Architecture proc R S C Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue Message queues • Currently many queue algorithms are programmed in SAP with limited control and error handling • Middleware will take over the expert task § Services work at different speeds • Requires that messages are held until they can be handled § Queue handler can do a central error management • E. g. Queues store undeliverable messages (dead letters) • Queue handlers can reprocess delayed messages § Queues can be database, files or memory arrays Logosworld 11 SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com Queues are the central element of an ESB § Queues are mandatory in distributed computing

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 12 Wednesday, January 26, 2022 Motivation: Managed Communication Protocol Conversion § Hybris uses Web protocols § SAP communicates only via RFC • SOAP (stateless calls only) via PI alone § Hybris must use SAP RFC Connector Mapping § We have a rising need in data mapping Logosworld • A good intuitive mapping editor allows for required flexibility SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Angeli/Grice Logosworld. com • There are many routines in SAP that can be reused for e. Commerce that only require additional mapping • Mapping to be done by middleware

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue 13 Load Throttling & Load Balancing • Currently throttling is done from by expensive ABAP coding • Coding can be replaced by Middleware § ESB needs to be able to funnel a flooding of requests into a number of inbound channels § The number of inbound channels should be adjustable with parameter on the fly § Any inbound request must be accepted by ESB without chance of rebound Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com There is a notoric imbalance between requesting tasks and possible receiver channels § Currently no load throttling active § Since load is not predictable, SAP must protect access

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue Fanout Proxy: Load Throttling Messages are stored in an MQ and then dispatched to processes that signal availability MQ Process Adapter Receiver Adapter Queue Janitor Process Adapter MQInbox Adapter Sender Logosworld SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue Logosworld 15 SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com

Logosworld Enterprise Architects Architecture Education Coaching Audit Realignment Rescue Pipes Logosworld 16 SOA City Logosworld. com Axel Angeli Enterprise Architecture & Project Rescue „Why do we need Middleware? “ Wednesday, January 26, 2022 Angeli/Grice Logosworld. com