\input{subfilepreamble}
\begin{document}
-\chapter{Prelude --- Introduction}%
+\chapter{Prelude}%
\label{chp:introduction}
-\begin{chapterabstract}
- \noindent%
- \begin{itemize}
- \item How many devices are there?
- \begin{itemize}
- \item Number of devices is big\footnote{\url{https://transformainsights.com/research/tam/market}, accessed on: \formatdate{2022}{10}{13}}
- \item It only grows
- \item they are powered by software
- \item These devices live in layered systems
- \end{itemize}
- \item What is the {IoT}?
- \begin{itemize}
- \item IoT is such a layered system
- \item Layers, device layer
- \end{itemize}
- \item What is impedance mismatch/semantic friction?
- \begin{itemize}
- \item heterogeneous between layers
- \item heterogeneous on the device/edge/perception layer
- \item Results in problems in software
- \item We see this also in web systems
- \end{itemize}
- \item What is TOP?\todo{hier al TOP uitleggen in \`e\`en zin? of alleen benoemen}
- \begin{itemize}
- \item declarative workflow language (partiture AND conductor)
- \item iTask for distributed web applications.
- \end{itemize}
- \item This thesis: how to orchestrate this concerto of devices?
- \begin{itemize}
- \item Embedded devices require special code (different clef/key)
- \item DSL is a special language in a language to facilitate this (part 1)
- \item mTask is a TOP language for IoT (part 2)
- \item This approach is called tierless programming (part 3)
- \end{itemize}
- \end{itemize}
-
- This chapter provides the required background material, an overview of the concrete contributions and a reading guide.
-
-% The sheer number of connected devices around us is mind boggling and seems increases exponentially for many years.
-% In 2022, there is an estimated number of 13.4 billion of devices connected that sense, act or otherwise interact with people and the physical world surrounding us\footnote{\url{https://transformainsights.com/research/tam/market}, accessed on: \formatdate{2022}{10}{13}}.
-% These devices, together with all the scaffolding and integration such as the various networks providing the communication, (cloud) computers realising the back end or administration and the devices in our pockets providing us with a view on the system are called the \gls{IOT}.
-% \Gls{IOT} systems can be seen as layered systems, where each layer is powered by different types of computers; programming languages and even programming paradigms.
-% This thesis shows a novel way of orchestrating these brobdingnagian systems using the \gls{TOP} paradigm.
-% It does so by giving a proof-of-concept implementation for a \gls{TOP} system specifically designed for the \gls{IOT}: \gls{MTASK}.
-% At the core of the \gls{MTASK} system is a \gls{DSL}, embedded in the general purpose \gls{TOP} system \gls{ITASK}.
-% Using the \gls{MTASK} system, all layers of an \gls{IOT} system can be programmed from a single declarative specification.
-
-\end{chapterabstract}
-
-\section{Internet of Things}
+In 2022, there were an estimated number of 13.4 billion of connected computers that sense, act or otherwise interact with people, other computers and the physical world surrounding us\footnotemark{}.
+\footnotetext{\url{https://transformainsights.com/research/tam/market}, accessed on: \formatdate{2022}{10}{13}}
+The variety among these devices is considerable but these devices have one thing in common though: they are all controlled by software.
+Concretely this means that programmers write code for these specific device to make sure the brains of the device---the processor---do what we want it to do.
+
+An increasing amount of these connected devices are so-called \emph{edge devices}.
+Typically these edge devices are small microprocessors containing various sensors and actuators to interact with the physical world.
+They are often part of and coordinated by a bigger system called \gls{IOT} systems.
+
+
+%These ed
+%These edge devices differ very much from other devices we see around us.
+%Compared to servers, laptops, tablets, or mobile phones they boast tiny amounts of memory, are powered by a slow but energy efficient microprocessor, only support low-level programming languages, and are not so easily reprogrammed.
+%Moreover, these edge devices differ among eachother as well by using various microprocessor architectures, different communication protocols and using a variety of device-specific toolchains.
+%As a result, there are many points of failure and programming these systems is difficult and error-prone.
+%
+%\Gls{TOP} is a novel programming paradigm that offers a solution to this problem.
+%In a \gls{TOP} language, from a single declarative specification of the work that needs to be done, ready-for-work applications are generated for all layers of the system.
+%However, the hardware requirements for traditional \gls{TOP} frameworks make it not feasable to run these generated applications on resource-constrained edge devices.
+%
+%\Glspl{DSL} can overcome this limitation because domain-specific knowledge is built into the programming language, allowing for lower hardware requirements.
+%This thesis presents \gls{MTASK}, a \gls{TOP} \gls{DSL} for edge devices that can be fully integrated with \gls{ITASK}, a \gls{TOP} \gls{DSL} for distributed multi-user workflow systems.
+%With \gls{MTASK}, all layers of an \gls{IOT} system can be programmed from a single programming language in a single programming paradigm.
+
+\section{Internet of things}\label{sec:back_iot}
The \gls{IOT} is growing rapidly and it is changing the way people and machines interact with the world.
-While the term \gls{IOT} briefly gained interest around 1999 to describe the communication of \gls{RFID} devices~\citep{ashton_internet_1999,ashton_that_2009}, it probably already popped up halfway the eigthies in a speech by \citet{peter_t_lewis_speech_1985}:
+While the term \gls{IOT} briefly gained interest around 1999 to describe the communication of \gls{RFID} devices \citep{ashton_internet_1999,ashton_that_2009}, it probably already popped up halfway the eighties in a speech by \citet{peter_t_lewis_speech_1985}:
\begin{quote}
\emph{The \glsxtrlong{IOT}, or \glsxtrshort{IOT}, is the integration of people, processes and technology with connectable devices and sensors to enable remote monitoring, status, manipulation and evaluation of trends of such devices.}
\end{quote}
-CISCO states that the \gls{IOT} only started when there where as many connected devices as there were people on the globe, i.e.\ around 2008~\citep{evans_internet_2011}.
+CISCO states that the \gls{IOT} only started when there where as many connected devices as there were people on the globe, i.e.\ around 2008 \citep{evans_internet_2011}.
Today, the \gls{IOT} is the term for a system of devices that sense the environment, act upon it and communicate with each other and the world.
These connected devices are already in households all around us in the form of smart electricity meters, fridges, phones, watches, home automation, \etc.
While devices are getting a bit faster, smaller, and cheaper, they keep these properties to an extent, greatly reducing the flexibility for dynamic systems where tasks are created on the fly, executed on demand, or require parallel execution.
These problems can be mitigated by dynamically sending code to be interpreted to the microprocessor.
With interpretation, a specialized interpreter is flashed in the program memory once that receives the program code to execute at runtime.
+Interpretation always comes with an overhead, making it challenging to create them for small edge devices.
+However, the hardware requirements can be reduced by embedding domain-specific data into the programming language to be interpreted, so called \glspl{DSL}.
-%weiser_computer_1991
-\section{\texorpdfstring{\Glsxtrlongpl{DSL}}{Domain-specific languages}}
+\section{\texorpdfstring{\Glsxtrlongpl{DSL}}{Domain-specific languages}}\label{sec:back_dsl}
% General
-Programming languages can be divided up into two categories: \glspl{DSL}\footnote{Historically this has been called DSEL as well.} and \glspl{GPL}~\citep{fowler_domain_2010}.
+Programming languages can be divided up into two categories: \glspl{DSL}\footnote{Historically this has been called DSEL as well.} and \glspl{GPL} \citep{fowler_domain_2010}.
Where \glspl{GPL} are not made with a demarcated area in mind, \glspl{DSL} are tailor-made for a specific domain.
Writing idiomatic domain-specific code in an \gls{DSL} is easy but this may come at the cost of the \gls{DSL} being less expressive to an extent that it may not even be Turing complete.
\Glspl{DSL} come in two main flavours: standalone and embedded\footnote{Also called external and internal respectively.} of which \glspl{EDSL} can again be classified into heterogeneous and homogeneous languages (see \cref{fig:hyponymy_of_dsls} for this hyponymy).
\begin{figure}[ht]
\centering
\includestandalone{hyponymy_of_dsls}
- \caption{Hyponymy of \glspl{DSL} (adapted from \citet[pg.\ 2]{mernik_extensible_2013})}%
+ \caption{Hyponymy of \glspl{DSL} (adapted from \citet[\citepage{2}]{mernik_extensible_2013})}%
\label{fig:hyponymy_of_dsls}
\end{figure}
Unfortunately it also means that they need to develop a compiler or interpreter for the language to be usable making standalone \glspl{DSL} costly to create.
Examples of standalone \glspl{DSL} are regular expressions, make, yacc, XML, SQL, \etc.
-A dichotomous approach is embedding the \gls{DSL} in a host language, i.e.\ \glspl{EDSL}~\citep{hudak_modular_1998}.
+The dichotomous approach is embedding the \gls{DSL} in a host language, i.e.\ \glspl{EDSL} \citep{hudak_modular_1998}.
By defining the language as constructs in the host language, much of the machinery is inherited and the cost of creating embedded languages is very low.
There is more linguistic reuse~\cite{krishnamurthi_linguistic_2001}.
There are however two sides to the this coin.
Furthermore, errors shown to the programmer may be larded with host language errors, making it difficult for a non-expert of the host language to work with the \gls{DSL}.
\subsection{Heterogeneity and homogeneity}
-\Citet{tratt_domain_2008} applied a notion from metaprogramming~\citep{sheard_accomplishments_2001} to \glspl{EDSL} to define homogeneity and heterogeneity of \glspl{EDSL} as follows:
+\Citet{tratt_domain_2008} applied a notion from metaprogramming \citep{sheard_accomplishments_2001} to \glspl{EDSL} to define homogeneity and heterogeneity of \glspl{EDSL} as follows:
\begin{quote}
+ \emph{
A homogeneous system is one where all the components are specifically designed to work with each other, whereas in heterogeneous systems at least one of the components is largely, or completely, ignorant of the existence of the other parts of the system.
+}
\end{quote}
Homogeneous \glspl{EDSL} are therefore languages that are solely defined as an extension to their host language.
For example, \citep{elliott_compiling_2003} describe the language Pan, for which the final representation in the host language is a compiler that will, when executed, generate code for a completely different target platform.
In fact, \gls{ITASK} and \gls{MTASK} are both heterogeneous \glspl{EDSL} and \gls{MTASK} specifically is a compiling \gls{DSL}.
-\section{\texorpdfstring{\Glsxtrlong{TOP}}{Task-oriented programming}}
+\section{\texorpdfstring{\Glsxtrlong{TOP}}{Task-oriented programming}}\label{sec:back_top}
\Gls{TOP} is a declarative programming paradigm designed to model interactive systems \citep{plasmeijer_task-oriented_2012}.
-Instead of dividing problems into layers or tiers, as is done in \gls{IOT} architectures as well, it deals with separation of concerns in a novel way.
+Instead of dividing problems into layers or tiers, as is done in \gls{IOT} architectures, it deals with separation of concerns in a novel way.
From the data types, utilising various \emph{type-parametrised} concepts, all other aspects are handled automatically (see \cref{fig:tosd}).
-This approach to software development is called \gls{TOSD}~\citep{wang_maintaining_2018}.
+This approach to software development is called \gls{TOSD} \citep{wang_maintaining_2018}.
\begin{figure}[ht]
\centering
\includestandalone{tosd}
\caption{\Gls{TOSD} approach.}
\end{subfigure}
- \caption{Separation of concerns in a traditional setting and in \gls{TOSD} (adapted from~\cite[pg.\ 20]{wang_maintaining_2018}).}%
+ \caption{Separation of concerns in a traditional setting and in \gls{TOSD} (adapted from~\cite[\citepage{20}]{wang_maintaining_2018}).}%
\label{fig:tosd}
\end{figure}
\begin{description}
\item[\Glsxtrshort{UI} (presentation layer):]
The \gls{UI} of the system is automatically generated from the representation of the type.
-% For instance, \gls{TOP} languages implemented in an \gls{FP} language often use generic programming or template metaprogramming to automatically achieve this.
-% \Gls{TOP} languages embedded in imperative programming languages may use introspection\todo{Do I want this sentence here?}.
Even though the \gls{UI} is generated from the structure of the datatypes, in practical \gls{TOP} systems it can be tweaked afterwards to suit the specific needs of the application.
\item[Tasks (business layer):]
A task is an abstract representation of a piece of work that needs to be done.
The \gls{UOD} from the business layer is explicitly and separately modelled by the relations that exist in the functions of the host language.
\end{description}
-The concept of \gls{TOP} originated from the \gls{ITASK} framework, a declarative workflow language for defining multi-user distributed web applications implemented as an \gls{EDSL} in the lazy pure \gls{FP} language \gls{CLEAN}~\citep{plasmeijer_itasks:_2007,plasmeijer_task-oriented_2012}.
+The concept of \gls{TOP} originated from the \gls{ITASK} framework, a declarative workflow language for defining multi-user distributed web applications implemented as an \gls{EDSL} in the lazy pure \gls{FP} language \gls{CLEAN} \citep{plasmeijer_itasks:_2007,plasmeijer_task-oriented_2012}.
While \gls{ITASK} conceived \gls{TOP}, it is not the only \gls{TOP} language.
Some \gls{TOP} languages arose from Master's and Bachelor's thesis projects (e.g.\ \textmu{}Task \citep{piers_task-oriented_2016} and LTasks \citep{van_gemert_task_2022}) or were created to solve a practical problem (e.g.\ Toppyt \citep{lijnse_toppyt_2022} and hTask \citep{lubbers_htask_2022}).
-Furthermore, \gls{TOPHAT} is a fully formally specified \gls{TOP} language designed to capture the essence of \gls{TOP} formally~\citep{steenvoorden_tophat_2019}.
+Furthermore, \gls{TOPHAT} is a fully formally specified \gls{TOP} language designed to capture the essence of \gls{TOP} formally \citep{steenvoorden_tophat_2019}.
created \textmu{}Task, a \gls{TOP} language for specifying non-interruptible embedded systems implemented as an \gls{EDSL} in \gls{HASKELL}.
\citet{van_gemert_task_2022} created LTasks, a \gls{TOP} language for interactive terminal applications implemented in LUA, a dynamically typed imperative language.
\citet{lijnse_toppyt_2022} created Toppyt, a \gls{TOP} language based on \gls{ITASK}, implemented in \gls{PYTHON}, but designed to be simpler and smaller.
Finally there is \gls{MTASK}, \gls{TOP} language designed for defining workflow for \gls{IOT} devices~\cite{koopman_task-based_2018}.
It is written in \gls{CLEAN} as an \gls{EDSL} fully integrated with \gls{ITASK} and allows the programmer to define all layers of an \gls{IOT} system from a single source.
-\section{Outline}
-\todo[inline]{uitbreiden}
-On Wikipedia, a rhapsody is defined as follows~\citep{wikipedia_contributors_rhapsody_2022}:
+\section{Reading guide}\label{sec:outline}
+This thesis presents a novel view on programming these \gls{IOT} systems as a purely functional rhapsody in three episodes.
+On Wikipedia, a rhapsody is defined as follows \citep{wikipedia_contributors_rhapsody_2022}:
\begin{quote}
- A \textbf{rhapsody} in music is a one-movement work that is episodic yet integrated, free-flowing in structure, featuring a range of highly contrasted moods, colour, and tonality. An air of spontaneous inspiration and a sense of improvisation make it freer in form than a set of variations.
+ \emph{A \emph{rhapsody} in music is a one-movement work that is episodic yet integrated, free-flowing in structure, featuring a range of highly contrasted moods, colour, and tonality.
+ An air of spontaneous inspiration and a sense of improvisation make it freer in form than a set of variations.}
\end{quote}
-This thesis follows the tradition and consists of three movements that are episodic yet integrated, a purely functional rhapsody.
-\Cref{prt:dsl} is about \gls{EDSL} techniques, \cref{prt:top} elaborates on \gls{TOP} for the \gls{IOT} and \cref{prt:tvt} compares traditional tiered \gls{IOT} architectures to a tierless architectures such as \gls{TOP}.
-The movements are readable independently if the reader is familiarised with the background material provided in \cref{chp:introduction}.
-The thesis wraps up with \cref{chp:conclusion} that provides a conclusion and an outlook on future work.
-\subsection*{\nameref{prt:dsl}}
-This movement is a cumulative---paper-based---movement that focusses on techniques for embedding \glspl{DSL} in \gls{FP} languages.
-After reading the first chapter, subsequent chapters in this movement are readable independently.
+\subsection*{\nameref{chp:introduction}}
+\Cref{chp:introduction} introduces the contents of the thesis, provides background material on \gls{IOT}, \glspl{DSL} and \gls{TOP} (\cref{sec:back_iot}, \cref{sec:back_dsl}, and \cref{sec:back_top} respectively) and an overview of the contributions including a more technical outline in \cref{sec:contributions}.
+
+\subsection*{\Fullref{prt:dsl}}
+
+\subsection*{\Fullref{prt:top}}
+
+\subsection*{\Fullref{prt:tvt}}
-\subsubsection*{\fullref{chp:dsl_embedding_techniques}}
-This chapter shows the basic \gls{DSL} embedding techniques and compares the properties of several embedding methods.
-This chapter is not based on a paper and written as a extra background material for the subsequent chapters in the movement.
+\subsection*{\nameref{chp:conclusion}}
+\Cref{chp:conclusion} wraps up with the coda that provides discussion and an outlook on future work.
-\subsubsection*{\fullref{chp:classy_deep_embedding}}
-This chapter is based on the paper: \bibentry{lubbers_deep_2022}\todo{change in-press when published}.
+\section{Contributions}\label{sec:contributions}
+\subsection*{\nameref{prt:dsl}}
+The \gls{MTASK} system is a heterogeneous \gls{EDSL} and during the development of it, several novel basal techniques for embedding \glspl{DSL} in \gls{FP} languages have been found.
+This first episode is a cumulative---otherwise known as paper-based---episode consisting of two papers published on novel embedding techniques.
+Both papers are readable independently.
+
+\subsubsection*{\Fullref{chp:classy_deep_embedding}}
+This chapter is based on the paper: \citeentry{lubbers_deep_2022}\todo{change in-press when published}.
While supervising \citeauthor{amazonas_cabral_de_andrade_developing_2018}'s \citeyear{amazonas_cabral_de_andrade_developing_2018} Master's thesis, focussing on an early version of \gls{MTASK}, a seed was planted for a novel deep embedding technique for \glspl{DSL} where the resulting language is extendible both in constructs and in interpretation using type classes and existential data types.
Slowly the ideas organically grew to form the technique shown in the paper.
-
-The research from this paper and writing the paper was solely performed by me.
\Cref{sec:classy_reprise} was added after publication and contains a (yet) unpublished extension of the embedding technique.
+The research from this paper and writing the paper was solely performed by me.
-\subsubsection*{\fullref{chp:first-class_datatypes}}
-This chapter is based on the paper: \bibentry{lubbers_first-class_2022}\todo{change when accepted}.
+\subsubsection*{\Fullref{chp:first-class_datatypes}}
+This chapter is based on the paper: \citeentry{lubbers_first-class_2022}\todo{change when accepted}.
It shows how to inherit data types from the host language in \glspl{EDSL} using metaprogramming.
-
+It does so by providing a proof-of-concept implementation using \gls{HASKELL}'s metaprogramming system: \gls{TH}.
+Besides showing the result, the paper also serves as a gentle introduction to using \gls{TH} and contains a thorough literature study on research that uses \gls{TH}.
The research in this paper and writing the paper was performed by me, though there were weekly meetings with Pieter Koopman and Rinus Plasmeijer in which we discussed and refined the ideas.
\subsection*{\nameref{prt:top}}
-This part is a monograph focussing on \glspl{TOP} for the \gls{IOT} and hence are the chapters best read in order.
-The monograph is compiled from the following papers and revised lecture notes.
+This is a monograph compiled from several papers and revised lecture notes on \gls{MTASK}, the \gls{TOP} system used to orchestrate the \gls{IOT}.
+It provides a gentle introduction to the \gls{MTASK} system elaborates on \gls{TOP} for the \gls{IOT}.
+\todo[inline]{outline the chapters}
\begin{itemize}
\item \citeentry{koopman_task-based_2018}
Pieter Koopman wrote it, I helped with the software and research.
\item \citeentry{lubbers_task_2018}
- This paper was an extension of my Master's thesis~\citep{lubbers_task_2017}.
+ This paper was an extension of my Master's thesis \citep{lubbers_task_2017}.
It shows how a simple imperative variant of \gls{MTASK} was integrated with \gls{ITASK}.
While the language was a lot different than later versions, the integration mechanism is still used in \gls{MTASK} today.
The research in this paper and writing the paper was performed by me, though there were weekly meetings with Pieter Koopman and Rinus Plasmeijer in which we discussed and refined the ideas.
\item \citeentry{koopman_simulation_2018}\footnotemark[\value{footnote}]\todo{change when published}
These revised lecture notes are from a course on the \gls{MTASK} simulator was provided at the 2018 \gls{CEFP}/\gls{3COWS} winter school in Ko\v{s}ice, Slovakia.
-
Pieter Koopman wrote and taught it, I helped with the software and research.
\item \citeentry{lubbers_writing_2019}\footnotemark[\value{footnote}]\todo{change when published}
These revised lecture notes are from a course on programming in \gls{MTASK} provided at the 2019 \gls{CEFP}/\gls{3COWS} summer school in Budapest, Hungary.
-
Pieter Koopman prepared and taught half of the lecture and supervised the practical session.
I taught the other half of the lecture, wrote the lecture notes, made the assignments and supervised the practical session.
\item \citeentry{lubbers_interpreting_2019}
This paper shows an implementation for \gls{MTASK} for microcontrollers in the form of a compilation scheme and informal semantics description.
-
The research in this paper and writing the paper was performed by me, though there were weekly meetings with Pieter Koopman and Rinus Plasmeijer.
\item \citeentry{crooijmans_reducing_2022}\todo{change when published}
This paper shows how to create a scheduler so that devices running \gls{MTASK} tasks can go to sleep more automatically.
- Furthermore, it shows how to integrate hardware interrupts into \gls{MTASK}.
The research was carried out by \citet{crooijmans_reducing_2021} during his Master's thesis.
I did the daily supervision and helped with the research, Pieter Koopman was the formal supervisor and wrote most of the paper.
\item \emph{Green Computing for the Internet of Things}\footnote{
This work acknowledges the support of the Erasmus+ project ``SusTrainable---Promoting Sustainability as a Fundamental Driver in Software Development Training and Education'', no. 2020--1--PT01--KA203--078646}\todo{change when published}
These revised lecture notes are from a course on sustainable programming using \gls{MTASK} provided at the 2022 SusTrainable summer school in Rijeka, Croatia.
-
Pieter prepared and taught a quarter of the lecture and supervised the practical session.
I prepared and taught the other three quarters of the lecture, made the assignments and supervised the practical session\todo{writing contribution}.
\end{itemize}
\subsection*{\nameref{prt:tvt}}
+\Cref{prt:tvt} is based on a journal paper that quantitatively and qualitatively compares traditional \gls{IOT} architectures with \gls{IOT} systems using \gls{TOP} and contains a single chapter.
This chapter is based on the journal paper: \citeentry{lubbers_could_2022}\todo{change when published}\footnote{This work is an extension of the conference article: \citeentry{lubbers_tiered_2020}\footnotemark{}}.
\footnotetext{This paper was partly funded by the Radboud-Glasgow Collaboration Fund.}
-It compares programming traditional tiered architectures to tierless architectures by showing a qualitative and a quantitative four-way comparison of a smart campus application.
-
+It compares programming traditional tiered architectures to tierless architectures by showing a qualitative and a quantitative four-way comparison of a smart-campus application.
Writing the paper was performed by all authors.
I created the server application, the \gls{CLEAN}/\gls{ITASK}/\gls{MTASK} implementation (\glsxtrshort{CWS}) and the \gls{CLEAN}/\gls{ITASK} implementation (\glsxtrshort{CRS})
-Adrian Ramsingh created the \gls{MICROPYTHON} implementation (\glsxtrshort{PWS}), the original \gls{PYTHON} implementation (\glsxtrshort{PRS}) and the server application were created by Jeremy Singer, Dejice Jacob and Kristian Hentschel~\citep{hentschel_supersensors:_2016}.
+Adrian Ramsingh created the \gls{MICROPYTHON} implementation (\glsxtrshort{PWS}), the original \gls{PYTHON} implementation (\glsxtrshort{PRS}) and the server application were created by \citet{hentschel_supersensors:_2016}.
\input{subfilepostamble}
\end{document}
repositories / phd-thesis.git / blobdiff