Business Process Modeling and Execution -- A Compiler for Distributed Microservices

0.4 MB·

by  Robert Singer

Business Process Modeling and Execution–A Compiler for Distributed Microservices
Robert Singer
Department of Computer Sciences
FH JOANNEUM–University of Applied Sciences
Graz, Austria
[email protected]
Abstract—In this paper, we propose to rethink the dominant that coordinate work through the exchange of messages. We
logicofhowtomodelbusinessprocesses.Wethinkthatanactor discuss general concepts for such an approach and present an
based approach supports in a much better way the fundamental
architecture for a concrete realization dependent on certain
natureofbusinessprocesses.Wepresentaproposalforacompiler
technological decisions.
6 architecture to model and execute business processes as a set
1 of communicating microservices that are hosted on a general In section II we review the typical architecture of work-
0 purpose virtual machine for distributed execution. flow systems. Then in section III we present and discuss an
2 Index Terms—S-BPM, Actor, Compiler, Virtual Machine, Er- architecture of actor based workflow systems. Based on this
n lang, Elixir we will work out the main differences between those two
a methodologies. Furthermore, after a short literature review of
J
I. INTRODUCTIONANDMOTIVATION a “compiler-engine” proposal in section IV we will propose
2
and discuss an approach based on actors. Furthermore, we
2 Recent industrial activities demand initiatives towards the
give a short review of S-BPM. This includes the explanation
digital transformation of business processes. Furthermore, the

] of the modeling notation and the formal background behind
industrialinternetrequiresrethinkingactualpracticesandtools
E
the scenes. Afterward, we discuss a methodology to translate
for distributed business processes based on communicating
S
S-BPM models into compilable code.
. human and (smart) machine actors.
s
c During recent years, tools have emerged to support the II. TRADITIONALWORKFLOWSYSTEM
[ execution of business processes, so-called Business Process
A typical conceptual architecture of a workflow system as
1 Management Systems (BPMS). Most of these tools are build
part of a business process management system is depicted in
v around the de facto standard for business process modeling
Figure 1.
6 languages, namely Business Process Model and Notation
7
(BPMN 2.x).
9 Meta-­Metamodel Metamodel Model
5 The standard may be suitable for modeling purposes, but DNeoftinaittiioonn DPerfoincietsiosn DPerfoincietsiosn ReprVesiseunatlation
Language Language Tool
0 does not directly support the execution of business process
1. models [1] [2] [3] [4]. That means, there is a gap between TPerochcensicsa  Dl  escription
e.g.  Active  Directory
0 the conceptual model and the digitized and executable repre- exteirnnteagl  fruantecdtio  onrality OrgSatrnuizcatutiroenal RePproocseitsosry Service EAI  Adapter
6 sentation. Furthermore, modeling of business processes needs
arXiv:1 atceinasoppaTnelaoycbutiiiaslociilatnvliylegerssnckfoooaitlmrrlmesien,atelySxthpmlpaiiescanralgillewulnayaencgaedneksosnMtien[se5asdav],biau[sim6mltar]aob,EcdlseteniuoltciiennnhrgpamarnisdnsaeonBcstyoaP(tnMSiccoMoenNmpsE.tpu)Taba[nhla7iisez]ees.asde-, APCPdeDoemrarnPffsorfioKinohrgrecbmimuseoytarasa  rasannr
 tdctciioeoe
 nn   Workflow
 EnIngsPiRntraeuoDnncacetetisma(ss
 e)A
 of
  HuImnsMPIantrnaoot
 endcInrceufetslaee(scsr

 ea)B&
 co
 tfi
 on
  ∙∙∙ Enterprise
 Application
 Integration ERP-­‐System
Indicators
Task
 List
on actor models have emerged. The standard for an actor
based approach for business process modeling is the so-called
Process  Participant
Subject-oriented Business Process Management (S-BPM) [8]
Fig.1.Typicalarchitectureofaworkflowsystem.[13]
approach.
In summary, S-BPM treats any business process as a
Ashortdescriptionofthedepictedarchitectureisasfollows:
(loosely)couplednetworkofActors,whichcanbeseenasmi-
business process models are stored in a repository; we also
croservices. S-BPM is a mature approach, as has been proven
need a formal model of the organization, so we can link
in theory and practice [9] [8] [10] [11] [12]. Nevertheless, in
organizational groups, roles and individual persons with the
this work we now want to propose a further paradigm change
activities of the process model (who is doing what). Any
andtogetridofmonolithicapplicationsfortheexecutionand
process also has transient entities, which change state during
management of business processes.
process execution—the so-called business objects (BO). Pro-
Inthiswork,weinvestigatehowtocompiledirectlyS-BPM cess models can be uploaded to and started by the workflow
models into a set of executable processes or microservices engine; they are interpreted by the software logic of the
application (process execution). Furthermore, it is important A nearly similar approach has been proposed by Al-
to understand that there must be some mechanism to interact bert Fleischmann who developed a business process model-
withhumanprocessparticipants.Firstly,theapplicationneeds ing methodology called PASS Parallel Activity Specification
to create and maintain a task list to distribute work [14]. Scheme (PASS) [9], which itself is based on Calculus of
Secondly, a task requires some input (data) from a human Communicating Systems (CCS) [19] [20] [21], a process
actor. Typically, a task is presented as a form based window calculus describing reactive systems [22]. Later, this concept
totheprocessparticipant,whichincludessomeread-onlydata has evolved into the so-called Subject-oriented Business Pro-
and offers some interactive elements to enter or change data; cess Management (S-BPM) methodology [8]. In short, this
the forms have to be designed and developed manually, or, methodologyincludesallnecessaryconceptstodefinereactive
can be generated automatically from business objects. Finally, and executable models of business processes.
we also have the need to interact with other systems in the
An S-BPM process is defined via the communication ex-
enterprise,whichnowadaystypicallyisdoneviaservicecalls.
change channels between subjects (actors are instantiated
Thechallengeliesintheautomatictranslationfromprocess subjects in this context, or the other way round—subjects
model to executable model. That is the reason the BPMN 2.x are generalizations of actors). Additionally, each subject has a
standard document differentiates between several compliance defined (but invisible to the outside world) internal behavior,
classes. whichisdeterminedasaprocessflowusingstatesforreceiving
orsendingamessage(toanothersubject),andstatesinwhich
However, the dominant logic how to define business pro-
the subject is doing some work. States can be flagged as
cesses is not necessarily the only thinkable one and other
startingorendingstatesandareconnectedusingdirectedarcs.
approaches offer some promising possibilities to overcome
In our approach, we think of subjects as actors. In the context
severaloftheobstaclesweareconfrontedwithinthepractical
of BPM, actors define who is doing what, as they are mapped
use of BPMS.
toaresourceforexecution(organizationalroles).Typically,S-
BPMmodelsconsistoftwotypesofrepresentations:aSubject
III. ACTORBASEDWORKFLOWSYSTEMS
Interaction Diagram (SID) and a set of Subject Behavior
Diagrams (SBD). The SID includes the subjects (this are the
A. Motivation
actors), the messages exchanged between the actors and the
We agree that software engineering has to support business business objects attached to the messages. The SBD includes
and not the other way round. However, it could be prolific all possible state sequences of an actor: a finite set of send,
to learn from software engineering [15]. Over the last couple receive and function states.
of years, new concepts have emerged or got more attention, Accordingtoourdefinition,anyactorcanberepresentedas
as, reactive and flow-based programming. There is also an in- aFiniteStateMachine(FSM)withstatesasmentionedabove,
creasinginterestinmicroservices,functionalprogrammingand theso-calledinternalbehavior.Furthermore,statechangescan
actor based systems to support the need to develop solutions betriggeredbyreceivingmessagesfromotheractors[23].An
that are responsive, resilient, elastic and message driven—the actor or subject is a general concept and can be instantiated
core requirements stated in the Reactive Manifesto [16]. by a human or machine. Based on the following conceptual
Furthermore, large systems are composed of smaller ones architecture,asdepictedinFigure2andFigure3,wehavede-
and, therefore, depend on the reactive properties of their velopedanentirelyfunctionalS-BPMworkflowsolutionusing
constituents. This leads to the concept of microservices [17] the Microsoft Windows Workflow Foundation functionality as
as a design pattern to build reactive systems meeting the discussed in [24] and [25]; for a more detailed discussion of
requirements mentioned before. The microservice architec- the architecture please consult these references.
tural style is an approach to understanding any application
A generalized architecture of an actor based workflow
as a collection of small services, each of them running in
systems is schematically depicted in Figure 2.
its process environment and communicating with lightweight
mechanisms; state changes of a service can only be triggered
byreceivingcertainmessagetypesandbusinessobjects(data). Human
 Interaction
  Process

Task
 List Module
 &
  Runtime Performance

Interface Data Dashboard
Key  
Performance  
B. Foundation Supervisor
 Process Supervisor
 Process Indicators
Process  Participant Instances
 of
 Process
 A Instances
 of
 Process
 B
Instanceof
  Instanceof

pibbturaossTisaeihncdeephsooespnssrsopraiobprcooloteoctseeradtslomsiennodsod.ecweroWilvsmiees[p,1uit8tnhthe]nianroatkvsr,ecbaitateaihsvneaepcdtreem—bomuenasituhisfnmoomedrsmscesanatntpolidroominbdceeoaedtdtsteesebrlfeimonfmrogorondeadee—pewls-l BehPaevrMMifRooWeeeSuresscmrosse
 noraaidskvfgg
 oeAeemcteo
 r
 B MIIennsAsAsAsttcccaaatttgnnoooeccrrr

 ee

 DABCooisffp

 atcher MIIennsssAAAsttcccaaatttgnnoooeccrrree

 DXYZooisffp

 atcher Enterprise
 Application
 Integration
Workflow
 Engine
approaches in the domain of BPM; the actor model supports
all mentioned requirements. Fig.2.Architectureofanactorbasedworkflowsystem.[13]
Themaincomponentsoftheactor-basedarchitectureareas B. An Actor-based Approach
follows(Figure2):theworkflowenginemanagesthebusiness
Basedonsimilarideas,butmotivatedbytheactormodel,we
processesviasupervisorprocesses;theworkflowengineloads
propose to investigate a different approach. Thinking bottom
themodelfromtherepositoryandstartsthesupervisorprocess
up, we can review available technology which inherently
that itself is responsible for starting all needed actors. Each
supports the development and execution of actor models.
supervisor process manages one instance of a process model.
Because of the underlying formal models, we think that a
When a business process ends, the responsible supervisor
functional programming language would be a good starting
process is terminated. Each business process has a dedicated
point for further research. The main reason is that business
instance of a message dispatcher that is responsible for
processes are highly concurrent; the lack of mutable state—as
routing the messages between all actors and between actors
in functional languages—makes concurrency almost trivial.
and the supervisor process (intra-process communication).
1) A Virtual Machine for Processes: So we could eas-
Sending messages between message dispatchers establishes
ily identify, for example, the following frameworks and/or
inter-process communication.
programming languages as candidates for hosting business
In Figure 3 we see, that based on the depicted architecture
processesmodeledascommunicatingactors:AKKAandScala
it is possible to distribute actor based business processes over
(on the Java Virtual Machine) and Erlang or Elixir (on the
more than one workflow engine, as long as we can route
Erlang Virtual Machine)
messagesbetweenthem.Routingmessagesbetweenactorsisa
significant step to establish inter-company business processes. Using a Virtual Machine (VM) has many advantages, such
as, for example, to provide an abstraction layer from the
operating system. Furthermore, we think that it is much more
HumMIannot
 edInruftlaeecr
 ea&c
 tion
  RuDnattimae HumMIannot
 edInruftlaeecr
 ea&c
 tion
  RuDnattimae efficient using a well established and general purpose VM
instead developing a specific BPM-VM—as long as it fits the
Supervisor
 Process Supervisor
 Process Supervisor
 Process Supervisor
 Process purpose. Verifying the feasibility of using the Erlang Run-
Instances
 of
 Process
 A Instances
 of
 Process
 B Instances
 of
 Process
 A Instances
 of
 Process
 B
InsAtcatnocr
 eAof
  InsAtcatnocre
 Xof
  InsAtcatnocr
 eAof
  InsAtcatnocre
 Xof
  Time System (ERTS) as VM for the execution of compiled
business process models is the aim of this research proposal.
InsAtcatnocr
 eBof
  InsAtcatnocre
 Yof
  InsAtcatnocr
 eBof
  InsAtcatnocre
 Yof

People (and machines) coordinate work through the ex-
InsAtcatnocre
 Cof
  InsAtcatnocre
 Zof
  InsAtcatnocre
 Cof
  InsAtcatnocre
 Zof
  change of messages. This is our understanding of what a
Message
 Dispatcher Message
 Dispatcher Message
 Dispatcher Message
 Dispatcher business process is—and that is the essence of Erlang; conse-
Workflow
 Engine
 Company
 ABC Workflow
 Engine
 Company
 XYZ quently, we see business processes as a network of connected
microservices. This sounds technical, but a microservice can
Intercompany  Process  Communication  
also be realized by a human actor. A microservice in our
Fig.3.Architectureofanactorbasedanddistributedworkflowsystem.[13] setting is simply an Erlang process.
In Erlang we have a hierarchy of (linked) processes that
IV. BUSINESSPROCESSCOMPILER exchangemessages;thesemessageexchangescanalsobedone
between processes hosted on different VMs that again can
A. Compiler-Engine Architecture
be hosted on different computers that are located in different
It seems worth to think about compiling business process networks. Furthermore, the language capabilities of Erlang
modelsintoexecutablecode.Recentlythishasbeendiscussed fit perfectly with the modeling concept of Subject-oriented
by [26] who proposed a compiler-engine architecture. Business Process Management.
One of the core concepts of this conceptual architecture is It is not our intention to propose the development of
the proposal to use a virtual machine for the execution of anotherworkflowengine,buttodevelopandstudyansoftware
business processes, as also discussed in [27]. Such a virtual architecture to compile process models based on the S-BPM
machine should be independent from the notation used to methodology into executable code, which furthermore can be
model a process. As logical consequence there is the need for executed on the chosen generic Virtual Machine.
an intermediate representation (IR), which cannot be directly
2) S-BPM as Modeling Language: All relevant modeling
used for modeling:
notations (BPMN, eEPC, or S-BPM) for business processes
It is necessary to provide a more high-level but are based on a graphical representation. The semantic of the
IR-conform processing language (like a subset of models is typically serialized as some XML structure. Such
BPMN and EPC). Therefore, that language has to an XML-file can be used as input for the compilation process
be automatically transformable into the IR. as depicted in Figure 4.
In the first step of the translation process a parser creates As noted in Figure 4 it is possible to show, that we can use
a parse tree, a Process Structure Tree (PST), which is then BPMN with a restricted set of modeling elements to define
used for translation; this is conform with compiler theory. For S-BPM processes models. In that case, we have to transform
a further discussion of this approach we refer to the work of the BPMN-XML into the form of the used tool. As with any
Prinz. et al. [26] [27]. BPMS, the organizational structure has to be mapped to the
builds on the Erlang VM and source code is also compiled
Enterprise Application Integration RReefpinrVeesimseuneatnlattsion ProcesSs- BDPeSBMf-iPnB cMiPotiMnNofno rTmoo l &Co Tnrfaonrsmfoitrym Cahteiocnk Syntax CTheecckhnical iEtnrretlEeoalni(.gbxAeirScaoTmcdo).edfi.eMleisos.strEellpaixrneigrsuesanogtueerdsceihnactveoerdneaanlclyaAnbSeyTa,sthibleyutabbietstmirsaicxttyepdsiycwnatliatlhyx
Process Description
not visible and accessible to the programmer. When programs
Mapping
User, Roles are compiled or interpreted, their source is transformed into
e.g. Active Directory
integrated or Organizational Process a tree structure being turned into byte-code or machine-code.
external functionality Structure Repository
This process is usually masked away. In Elixir the AST is
exposedinaformthatcanberepresentedbyElixir’sowndata
Fig.4.CreatingaS-BPMprocessmodelwithaProcessDefinitionTool:the
structures and a natural syntax to interact with it. Therefore,
S-BPMmodelcanbedefinedgraphically,asformallanguage
sentences[8][28],orwithareducedsetofBPMN2.xsymbols[29]aslong code can use the language capabilities to write directly code;
astheserializedmodelconformswithanXML-schemadefinitionforthe code interprets the model and constructs a source file that
tool(BPMS)thatusestheXML-fileforexecution.[13]
represents the model as Elixir source file.
The full compilation (production) flow is depicted in Fig-
process. The processes are stored in the process repository. ure6.Firsttheprocessmodelsareexportedfromtherepository
Figure 4 is a modified version of the upper part of Figure 1. in some XML format. This leads to a set of files: One file for
Function states can include Refinements that means calls of theSubjectInteractionDiagram(SID)whichdefinestheactors
external services. (subjects) of the business process, the messages between all
subjects and the business objects attached with the messages;
S-BPM is a fully quantified and formal language to define
businessobjectscanbesimpleorcomplexdatastructures.For
theinteractionofactorsandtodescribetheirinternalbehavior
eachSubjectBehaviorDiagram(SBD)wegetacorresponding
in a heterogeneous (human and machine actors) multi-actor
file defining the internal behavior of the actor (subject).
environment.
3) From Model to Code: On the consumer side (the side
that uses the models) the models are compiled into so-called RePproocseitsosry
.beam files. Each subject has to be converted into an Erlang
Export as XML
processandcanbeexecutedonanyErlangnode(seeFigure5).
Add generic
supervisor process
A supervisor process is linked with each subject to control
each instance and the network of communicating subjects— SID Svuispoerr- Svuispoerr-
[XML] [Elixir] [.beam]
the whole business process. This is also a standard approach Generate Elixir files Compile
forErlangapplications;pleaseconsult [30][31],forexample, SBD Subject Subject
for more information about Erlang. [XSMSBBLD]D [ESlSiBxBirD]D [.bSeSBaBmDD]
Model Repository Source Repository Binary Repository
Start, stop, distribute
Process Supervisor Process process instances
Repository Instances of Process A
Bpuroilg(drM aEmelitxmair- iXAnSMgT)L on demand InAstcatnocr eAof InsAtcatnocr eBof MAapnpaligceamtioennt
Fig.6.Thecompilationworkflow.[13]
Elixir Source
Code Instanceof
Elixir Compiler Actor C
Now, a parser takes these files as input and generates for
Erlang Node 1 Erlang Node 2
BEAM Files Management Process each SBD an Elixir source file. The information contained in
• Monitoring
RepFoisleit ory •• SIMntseatarats,n uScreteos Kp PIs theSID-fileisusedtoproducethemessageexchangebehavior
•Supervisor Process • Manage Versions of each SBD-file. Furthermore, based on a provided template
•Actor (Subject)
Behaviors
Erlang Node 0 file, a supervisor process for the specific business process has
Fig.5.Consumerside:themodelistranslatedintoexecutablecode.The tobegenerated.Thesupervisorprocesshasthe“control”over
compiledprocessesareloadedandsupervisedbyamanagementprocess. all other processes; that means this process is informed, for
ProcessescanbeexecutedondifferentErlangnodes,evenrunningin
example, if one of the subject instances crashes, or it can
distinctnetworks.[13]
be designed for performance measures (to measure a service
level, for instance). It can also be used for applying business
The idea of how to compile S-BPM processes builds on
rules to the overall message exchange between individual
theconceptofmetaprogramming—codethatwritescode.That
subjects [34].
means, the process model, consisting of several communicat-
ing subjects is transformed via a translation process into a The generated Elixir source files are compiled with the
source code file. This could be Erlang code, but as Elixir [32] Elixir compiler and are stored in a repository. An application
offers specific support for metaprogramming [33] we have has to be provided to manage the set of executable binaries
chosen it as our choice for the transformation process. Elixir and the running instances. So it has to provide functionality
to start a business process on one or more Erlang nodes— REFERENCES
the virtual machines. Furthermore, as supported by the ERTS,
this application could also update running instances with a [1] Object Management Group , “Business Process Model and Notation,”
new version (of course, this has to consider the actual state of Jul.2013.
[2] B.Silver,BPMNMethodandStyle,2nded. Cody-CassidyPress,2011.
the process or process component).
[3] E. Bo¨rger, “Approaches to modeling business processes: a critical
analysisofBPMN,workflowpatternsandYAWL,”Software&Systems
Modeling,2011.
V. CONCLUSIONANDFUTUREWORK [4] R. Singer, “User Centered Development of Agent-based Business Pro-
cessModelsandNotations,”arXiv:1404.2737,2014.
The feasibility to model any S-BPM process as Elixir or [5] T.SonteyaandL.Seymour,“TowardsanUnderstandingoftheBusiness
ProcessAnalyst:AnAnalysisofCompetencies,”JournalofInformation
Erlang process has been proven based on hand-crafted code
TechnologyEducation:Research,vol.11,pp.43–63,2012.
snippets; nevertheless, this is a trivial fact and only based on
[6] R. Seethamraju, “Business process management: a missing link in
the fact that both S-BPM and Elixir are based on communi- business education,” Business Process Management Journal, vol. 18,
cating actors. However, how exactly to define a suitable data no.3,pp.532–547,2012.
[7] R.Singer,“BusinessProcessManagementinSmall-andMedium-sized
modelforS-BPMprocessesandhowtoautomaticallygenerate
Enterprises: An Empirical Study,” in Proceedings of the 7th Interna-
source files from this data model (via metaprogramming) has tional Conference on Subject-Oriented Business Process Management,
tobeinvestigatedindetailandisanongoingresearchactivity. ser.S-BPMONE’15. ACM,2015.
[8] A. Fleischmann, W. Schmidt, C. Stary, S. Obermeier, and E. Bo¨rger,
For practical use, further aspects have to be considered. We Subject-OrientedBusinessProcessManagement. Springer,2012.
have identified the following topics for which solutions have [9] A.Fleischmann,DistributedSystems:Softwaredesignandimplementa-
tion. Springer,1994.
tobeidentifiedandintegratedintoanoverallBusinessProcess
[10] S.Rass,A.Fleischmann,andR.Singer,S-BPMIllustrated. Springer,
ManagementSystem(BPMS).Thisisalsounderdevelopment; 2013.
our research is dedicated for industrial use, and many topics [11] A. Fleischmann, W. Schmidt, and C. Stary, Eds., S-BPM in the Wild.
Springer,2015.
have to be investigated:
[12] Metasonic.[Online].Available:http://metasonic.de
Firstly, there must also be a mechanism for the distribution [13] R. Singer, “Agent-Based Business Process Modeling and Execution:
Steps Towards a Compiler-Virtual Machine Architecture,” in Proceed-
of work for human actors; for example, there is no guarantee,
ings of the 8th International Conference on Subject-Oriented Business
that a task will be started or finished as intended. How to ProcessManagement,ser.S-BPMONE’16. ACM,2016.
handle all these possible and thinkable exceptions in a human [14] N. Russell, A. ter Hofstede, D. Edmond, and W. van der Aalst,
“Workflow Resource Patterns,” Eindhoven University of Technology,
interaction workflow?
Tech.Rep.,2004.
Anothertopicistheintegrationintoanorganizationalstruc- [15] V.GruhnandR.Laue,“Whatbusinessprocessmodelerscanlearnfrom
programmers,” Science of Computer Programming, vol. 65, no. 1, pp.
ture (roles and access rights), which can be challenging in the
4–13,2007.
case of distributed processes. There are some ideas how to [16] J. Bone´r, D. Farley, R. Kuhn, and M. Thompson. The reactive
handle this issue, but they have to be investigated in detail. manifesto.[Online].Available:http://www.reactivemanifesto.org
[17] S.Newman,BuildingMicroservices. O’Reilly,2015.
The most critical and yet not fully understood problem [18] C.Hewitt,P.Bishop,andR.Steiger,“AUniversalModularActorFor-
seems to be security. The ERTS provides a mechanism to malismforArtificialIntelligence,”in3rdInternationalJointConference
onArtificialIntelligence(IJCAI),1973.
control the rights to run a process, but there appears to be the
[19] R.Milner,ACalculusofCommunicatingSystems,ser.LNCS. Springer,
needformoreresearchtounderstandfullytheimplicationsfor 1980,vol.92.
the execution of business processes—especially if processes [20] E.Aitenbichler,S.Borgert,andM.Mu¨hlha¨user,“DistributedExecution
of S-BPM Business Processes,” in Subject-Oriented Business Process
span over more than one organizational unit.
Management, ser. CCIS, A. Fleischmann, W. Schmidt, R. Singer, and
A concept to handle business objects has to be developed: D.Seese,Eds.,vol.138. Springer,2010,pp.19–35.
[21] S.Borgert,J.Steinmetz,andM.Mu¨hlha¨user,“ePASS-IoS1.1:Enabling
in a technical sense, how to send business objects from an
Inter-enterpriseBusinessProcessModelingbyS-BPMandtheInternet
actor in company A to an actor in company B—considering of Service Concept,” in S-BPM ONE: Learning by Doing - Doing by
rights and safety issues, data integrity and so forth. Learning, ser. CCIS, W. Schmidt, Ed., vol. 213. Springer, 2011, pp.
190–211.
Furthermore, during development and research, other ap- [22] L.Aceto,A.Ingo´lfsdo´ttir,K.G.Larsen,andJ.Srba,ReactiveSystems.
proaches emerged that are also currently under investigation: CambridgeUniv.Press,2007.
[23] D.BrandandP.Zafiropulo,“OnCommunicatingFinite-stateMachines,”
we call it smart or intelligent business objects (smartBO).
JournaloftheAssociationforComputerMachinery,vol.30,no.2,pp.
A business process is based on data, the business objects. 323–342,1983.
Often BOs are seen as second class entities in a classical [24] R.Singer,J.Kotremba,andS.Rass,“ModelingandExecutionofMul-
tienterpriseBusinessProcesses,”inIEEE16thConferenceonBusiness
view. In our concept, smartBO know the business process.
Informatics(CBI),vol.2,2014,pp.68–73.
That means, dependent on their state; they know who is the [25] R. Singer and S. Raß, “Structured Communication - Approaching
nextactoraccordingtotheprocessdefinitionandtheyforward S-BPM with Microsoft Technologies,” in S-BPM in the Wild,
A.Fleischmann,W.Schmidt,andC.Stary,Eds. SpringerInternational
themselves to the next actor (or actors) for processing.
Publishing, 2015, pp. 235–255. [Online]. Available: http://dx.doi.org/
Uptonowthediscussedapproachanddesigndecisionshave 10.1007/978-3-319-17542-3 14
[26] T.M.Prinz,T.S.Heinze,W.Amme,J.Kretschmar,andC.Beckstein,
been proved very fruitful. Nevertheless, a lot of research and
“TowardsaCompilerforBusinessProcesses-AResearchAgenda,”in
development work has to be done. ServiceComputation2015. IARIA,2015.
[27] T.M.Prinz,“ProposalsforaVirtualMachineforBusinessProcesses,”in
ServicesandtheirComposition,7thCentralEuropeanWorkshop,ZEUS
2015,T.M.Prinz,Ed.,Jena,February2015.
[28] C.LangmannandR.Singer,“AConceptofText-basedBusinessProcess
Modeling,” FH JOANNEUM–University of Applied Sciences, Tech.
Rep.,2014.
[29] A.Fleischmann,“personalcommunication.”
[30] J.Armstrong,ProgrammingErlang,2nded. ThePragmaticProgram-
mers,2013.
[31] F.CesariniandS.Vinoski,DesigningforScalabilitywithErlang/OTP.
O’Reilly,2015.
[32] D.Thomas,ProgrammingElixir,1sted. ThePragmaticProgrammers,
2016.
[33] C. McCord, Metaprogramming Elixir. The Pragmatic Programmers,
2015.
[34] R. Singer and S. Raß, “Embodying Business Rules in S-BPM,” in S-
BPMintheWild. Springer,2015,pp.187–199.