DOCSLIB.ORG

Microservices Vs. Service-Oriented Architecture by Mark Richards Copyright © 2016 O’Reilly Media

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Microservices Vs. Service-Oriented Architecture by Mark Richards Copyright © 2016 O’Reilly Media Microservices vs. Service- Oriented Architecture Mark Richards Microservices vs. Service-Oriented Architecture by Mark Richards Copyright © 2016 O’Reilly Media. All rights reserved. Printed in the United States of America. Published by O’Reilly Media, Inc., 1005 Gravenstein Highway North, Sebastopol, CA 95472. O’Reilly books may be purchased for educational, business, or sales promotional use. Online editions are also available for most titles (http://safaribooksonline.com). For more information, contact our corporate/institutional sales department: 800-998-9938 or [email protected]. Editors: Nan Barber, Rachel Roumeliotis Interior Designer: David Futato Production Editor: Nicholas Adams Cover Designer: Randy Comer Copyeditor: Eileen Cohen Illustrator: Rebecca Demarest Proofreader: Nicholas Adams November 2015: First Edition Revision History for the First Edition 2015-11-17: First Release The O’Reilly logo is a registered trademark of O’Reilly Media, Inc. Microservices vs. Service-Oriented Architectures and related trade dress are trademarks of O’Reilly Media, Inc. While the publisher and the authors have used good faith efforts to ensure that the information and instructions contained in this work are accurate, the publisher and the authors disclaim all responsibility for errors or omissions, including without limitation responsibility for damages resulting from the use of or reliance on this work. Use of the information and instructions contained in this work is at your own risk. If any code samples or other technology this work contains or describes is sub‐ ject to open source licenses or the intellectual property rights of others, it is your responsibility to ensure that your use thereof complies with such licenses and/or rights. 978-1-491-95242-9 [LSI] Table of Contents Foreword. vii Preface. ix 1. The World of Service-Based Architectures. 1 Service Contracts 2 Service Availability 5 Security 7 Transactions 8 Too Much Complexity? 9 2. Comparing Service Characteristics. 11 Service Taxonomy 11 Service Ownership and Coordination 14 Service Granularity 17 Granularity and Pattern Selection 19 3. Comparing Architecture Characteristics. 21 Component Sharing 22 Service Orchestration and Choreography 24 Middleware vs. API Layer 30 Accessing Remote Services 33 4. Comparing Architecture Capabilities. 35 Application Scope 35 Heterogeneous Interoperability 36 v Contract Decoupling 39 5. Summary. 43 vi | Table of Contents Foreword People either love or hate the idea of microservices. I must admit that I was in the former camp initially but have changed my mind over the last six months. Originally, I had thought the management of a plethora of individual services that make up a full application would be fraught with error and troublesome to both development and operations staff. However, over the last year we have seen a rise in popularity of a key piece of technology that is now enabling us to take advantage of this design pattern in a more efficient manner. This new technology is the rise of the container application platform and the tight integration with DevOps principles around automa‐ tion and scalability. An organization can implement DevOps without microservices, but should not implement a microservice architecture without a DevOps culture. Using a container application platform for the deployment of micro‐ services will allow you to truly see the benefit of breaking up appli‐ cation logic into logical individual components. As your application grows in usage and demand, using this approach will allow you to quickly scale the most utilized components instead of scaling the entire application. As an example, one of the first applications that I developed many years ago was a CRM system that retrieved data from a datastore and then presented the information to the user. One of the most complex and non-performant bits of code was the actual searching of millions of customer records. Unfortunately, this code block was the most heavily used part of the system. In order to handle demand and the response times the users expected, we scaled the entire application just to have more instances of this search ser‐ vice. Keep in mind, this application was a full Java EE–based appli‐ cation, and therefore scaling would require additional hardware to handle the large and complex application. Had we had the tools we all have available today, such as a container application platform, we could have trivially scaled the search service to 50 containers while leaving the not-heavily-used services alone. This would have saved us a tremendous amount of time, headache, and cost while also pro‐ viding the users with the experience they desired. Are microservices the right solution for every application? Of course not. However, if you think that your application could take advan‐ tage of scaling independent components, give it a look and see if it fits well with the goal of your application. Of course, let’s not forget about the reuse aspect of microservices. Having your application logic broken up into independent compo‐ nents will afford you and your development team a tremendous amount of flexibility in reusing code across projects as well allow for a true polyglot environment where you can finally use the best tool for each individual task. I am excited about the adoption of microservices and the impact it will have on our craft. —Grant Shipley, Senior Manager, Developer Advocates, Red Hat, Inc. Preface In the mid-2000’s, service-oriented architecture (SOA) took the IT industry by storm. Numerous companies adopted this new architec‐ ture style as a way to bring better business functionality reuse into the organization and to enable the IT organization and the business to better communicate and collaborate with each other. Dozens of best practices for implementing SOA emerged at that time, as well as a plethora of third-party products to help companies implement SOA. Unfortunately, companies learned the hard way that SOA was a big, expensive, complicated architecture style that took too long to design and implement, resulting in failed projects that drove SOA out of favor in the industry. Today, microservices architecture is taking the IT industry by storm as the go-to style for developing highly scalable and modular appli‐ cations. Microservices architecture holds the promise of being able to address some of the problems associated with large, complex SOAs as well as the problems found with big, bloated monolithic applications. But how much do microservices and SOA differ? Is the industry destined to repeat the same experience with microservices as with SOA? In this report I walk you through a detailed comparison of the microservices and SOA architecture patterns. You will learn the basics of each of these architectures and core differences between them in terms of the architecture style, architecture characteristics, service characteristics, and capabilities. By using the information in this report, you will know how these two architecture styles differ from each other and which of the two is best suited for your particu‐ lar situation. ix CHAPTER 1 The World of Service-Based Architectures Both microservices architecture and SOA are considered service- based architectures, meaning that they are architecture patterns that place a heavy emphasis on services as the primary architecture com‐ ponent used to implement and perform business and nonbusiness functionality. Although microservices and SOA are very different architecture styles, they share many characteristics. One thing all service-based architectures have in common is that they are generally distributed architectures, meaning that service components are accessed remotely through some sort of remote- access protocol—for example, Representational State Transfer (REST), Simple Object Access Protocol (SOAP), Advanced Message Queuing Protocol (AMQP), Java Message Service (JMS), Microsoft Message Queuing (MSMQ), Remote Method Invocation (RMI), or .NET Remoting. Distributed architectures offer significant advantages over monolithic and layered-based architectures, includ‐ ing better scalability, better decoupling, and better control over development, testing, and deployment. Components within a dis‐ tributed architecture tend to be more self-contained, allowing for better change control and easier maintenance, which in turn leads to applications that are more robust and more responsive. Distributed architectures also lend themselves to more loosely coupled and modular applications. 1 In the context of service-based architecture, modularity is the prac‐ tice of encapsulating portions of your application into self-contained services that can be individually designed, developed, tested, and deployed with little or no dependency on other components or serv‐ ices in the application. Modular architectures also support the notion of favoring rewrite over maintenance, allowing architectures to be refactored or replaced in smaller pieces over time as the busi‐ ness grows—as opposed to replacing or refactoring an entire appli‐ cation using a big-bang approach. Unfortunately, very few things in life are free, and the advantages of distributed architectures are no exception. The trade-offs associated with those advantages are, primarily, increased complexity and cost. Maintaining service contracts, choosing the right remote-access protocol, dealing with unresponsive or unavailable services, secur‐ ing remote services, and managing distributed transactions are just a few of the many complex issues you
Load more

Recommended publications
  • Software Architecture: Past, Present, Future
    Software Architecture: Past, Present, Future Wilhelm Hasselbring 1 Introduction For large, complex software systems, the design of the overall system structure (the software architecture) is an essential challenge. The architecture of a software system defines that system in terms of components and connections among those components [55, 58]. It is not the design of that system which is more detailed. The architecture shows the correspondence between the requirements and the constructed system, thereby providing some rationale for the design decisions. This level of design has been addressed in a number of ways including informal diagrams and descriptive terms, module interconnection languages, and frameworks for systems that serve the needs of specific application domains. An architecture embodies decisions about quality properties. It represents the earliest opportunity for evaluating those decisions. Furthermore, reusability of components and services depends on how strongly coupled they are with other components in the system architecture. Performance, for instance, depends largely upon the complexity of the required coordination, in particular when the components are distributed via some network. The architecture is usually the first artifact to be examined when a programmer (particularly a maintenance programmer) unfamiliar with the system begins to work on it. Software architecture is often the first design artifact that represents decisions on how requirements of all types are to be achieved. As the manifestation of early design decisions, it represents design decisions that are hardest to change and hence most deserving of careful consideration. W. Hasselbring () Kiel University, Kiel, Germany e-mail: [email protected] © The Author(s) 2018 169 V.
    [Show full text]
  • An Experimental Study on Microservices Based Edge Computing Platforms Qian Qu, Ronghua Xu, Seyed Yahya Nikouei, Yu Chen Dept
    1 An Experimental Study on Microservices based Edge Computing Platforms Qian Qu, Ronghua Xu, Seyed Yahya Nikouei, Yu Chen Dept. of Electrical & Computer Engineering, Binghamton University, SUNY, Binghamton, NY 13902, USA fqqu2, rxu22, snikoue1, [email protected] Abstract—The rapid technological advances in the Internet of development and easy deployment among multiple service Things (IoT) allows the blueprint of Smart Cities to become providers. feasible by integrating heterogeneous cloud/fog/edge computing Because of many attractive features, such as good scalabil- paradigms to collaboratively provide variant smart services in our cities and communities. Thanks to attractive features like fine ity, fine granularity, loose coupling, continuous development, granularity and loose coupling, the microservices architecture and low maintenance cost, the microservices architecture has has been proposed to provide scalable and extensible services in emerged and gained a lot of interests both in industry and large scale distributed IoT systems. Recent studies have evaluated academic community [17], [21]. Compared to traditional SOAs and analyzed the performance interference between microser- in which the system is a monolithic unit, the microservices vices based on scenarios on the cloud computing environment. However, they are not holistic for IoT applications given the architecture divides an monolithic application into multiple restriction of the edge device like computation consumption and atomic microservices that run independently on distributed network capacity. This paper investigates multiple microservice computing platforms. Each microservice performs one specific deployment policies on edge computing platform. The microser- sub-task or service, which requires less computation resource vices are developed as docker containers, and comprehensive ex- and reduces the communication overhead.
    [Show full text]
  • Comparing Service- Based Architectures
    Comparing Service- based Architectures @neal4d nealford.com 1 agenda Micro Service-oriented Service-based 2 Service-oriented Architecture 3 origins: hubs System B System A System C 4 origins: hubs System B System A System C System D (ftp only) 5 origins: hubs System E (http only) System B System A System C System D (ftp only) 6 origins: hubs System E (http only) System B System A System C System D (ftp only) 7 origins: hubs System E (http only) System B Integration System A Hub System C System D (ftp only) 8 origins: hubs System E (http only) System B Integration System A Hub System C System D (ftp only) 9 origins: hubs System E (http only) System B Integration System A Hub System C System D (ftp only) 10 origins: hubs looks great, but what about single point of failure and performance bottleneck considerations? 11 orchestration hub intelligent hub service oriented architecture / enterprise service bus pattern 12 service-oriented architecture abstraction service taxonomy shared resources middleware interoperability 13 service-oriented architecture business services BS BS BS BS BS BS message bus process choreographer service orchestrator enterprise services ES ES ES ES ES ES application services AS infrastructure services IS 14 service-oriented architecture business services BS BS BS BS BS BS messageabstract bus enterprise-level coarse-grained process choreographer owned and defined by business users data represented as WSDL, BPEL, XML, etc. service orchestrator no implementation - only name, input, and output enterpriseAre we services
    [Show full text]
  • Case Study on Building Data- Centric Microservices
    Case Study on Building Data- Centric Microservices Part I - Getting Started May 26, 2020 | Version 1.0 Copyright © 2020, Oracle and/or its affiliates Public DISCLAIMER This document in any form, software or printed matter, contains proprietary information that is the exclusive property of Oracle. Your access to and use of this confidential material is subject to the terms and conditions of your Oracle software license and service agreement, which has been executed and with which you agree to comply. This document and information contained herein may not be disclosed, copied, reproduced or distributed to anyone outside Oracle without prior written consent of Oracle. This document is not part of your license agreement nor can it be incorporated into any contractual agreement with Oracle or its subsidiaries or affiliates. This document is for informational purposes only and is intended solely to assist you in planning for the implementation and upgrade of the product features described. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, and timing of any features or functionality described in this document remains at the sole discretion of Oracle. Due to the nature of the product architecture, it may not be possible to safely include all features described in this document without risking significant destabilization of the code. TABLE OF CONTENTS DISCLAIMER INTRODUCTION ARCHITECTURE OVERVIEW Before You Begin Our Canonical Application
    [Show full text]
  • Evaluating Service-Oriented and Microservice Architecture Patterns to Deploy Ehealth Applications in Cloud Computing Environment
    applied sciences Article Evaluating Service-Oriented and Microservice Architecture Patterns to Deploy eHealth Applications in Cloud Computing Environment Huriviades Calderón-Gómez 1,2 , Luis Mendoza-Pittí 1,2 , Miguel Vargas-Lombardo 2,* , José Manuel Gómez-Pulido 1,3 , Diego Rodríguez-Puyol 3,4,5, Gloria Sención 6 and María-Luz Polo-Luque 3,7 1 Department of Computer Science, University of Alcalá, 28805 Alcalá de Henares, Spain; [email protected] (H.C.-G.); [email protected] (L.M.-P.); [email protected] (J.M.G.-P.) 2 e-Health and Supercomputing Research Group (GISES), Technological University of Panama, 0819-07289 Panama City, Panama 3 Department of Medicine and Medical Specialties, Ramón y Cajal Institute for Health Research (IRYCIS), 28034 Madrid, Spain; [email protected] (D.R.-P.); [email protected] (M.-L.P.-L.) 4 Foundation for Biomedical Research, Hospital Universitario Príncipe de Asturias, 28805 Alcalá de Henares, Spain 5 Department of Medicine and Medical Specialties, University of Alcalá, 28805 Alcalá de Henares, Spain 6 School of Medicine Autonomous, University of Santo Domingo, Santo Domingo 10105, Dominican Republic; [email protected] 7 Department of Nursing and Physiotherapy, University of Alcalá, 28801 Alcalá de Henares, Spain * Correspondence: [email protected] Citation: Calderón-Gómez, H.; Mendoza-Pittí, L.; Vargas-Lombardo, Abstract: This article proposes a new framework for a Cloud-based eHealth platform concept focused M.; Gómez-Pulido, J.M.; on Cloud computing environments, since current and emerging approaches using digital clinical Rodríguez-Puyol, D.; Sención, G.; history increasingly demonstrate their potential in maintaining the quality of the benefits in medical Polo-Luque, M.-L.
    [Show full text]
  • From Component-Based Architectures to Microservices: a 25-Years-Long Journey in Designing and Realizing Service-Based Systems
    From Component-based Architectures to Microservices: A 25-years-long Journey in Designing and Realizing Service-based Systems Giuseppe De Giacomo[0000−0001−9680−7658], Maurizio Lenzerini[0000−0003−2875−6187], Francesco Leotta[0000−0001−9216−8502], and Massimo Mecella[0000−0002−9730−8882] Sapienza Universit`adi Roma Dipartimento di Ingegneria Informatica Automatica e Gestionale fdegiacomo,lenzerini,leotta,[email protected] Abstract. Distributed information systems and applications are gen- erally described in terms of components and interfaces among them. How these component-based architectures have been designed and im- plemented evolved over the years, giving rise to the so-called paradigm of Service-Oriented Computing (SOC). In this chapter, we will follow a 25-years-long journey on how design methodologies and supporting technologies influenced one each other, and we discuss how already back in the late 90s the ancestors of the SOC paradigm were there, already paving the way for the technological evolution recently leading to mi- croservice architectures and serverless computing. Keywords: components · SOC · middleware technologies · microser- vices · design methodologies 1 Introduction Divide et impera1 describes an approach, relevant to many fields, where, to solve a problem, it is required or advantageous to break or divide what opposes the solution. As an example, in computer science and engineering, it is applied at the level of standalone programs, by organizing codes in functions, classes and libraries, but it is also at the basis of how complex business processes, spanning several departments/offices of the same organization and/or different organizations, are implemented by making different parties collaborating on a computer network [1].
    [Show full text]
  • Gremlin: Systematic Resilience Testing of Microservices
    Gremlin: Systematic Resilience Testing of Microservices Victor Heorhiadi Shriram Rajagopalan Hani Jamjoom Michael K. Reiter Vyas Sekar UNC Chapel Hill IBM T. J. Watson Research IBM T. J. Watson Research UNC Chapel Hill Carnegie Mellon University [email protected] [email protected] [email protected] [email protected] [email protected] Abstract—Modern Internet applications are being disaggre- Company Downtime Postmortem findings gated into a microservice-based architecture, with services Parse.ly, 13 hours Cascading failure due to message bus being updated and deployed hundreds of times a day. The 2015 [25] overload accelerated software life cycle and heterogeneity of language CircleCI, 17 hours Cascading failure due to database over- runtimes in a single application necessitates a new approach 2015 [19] load BBC, 48 hours Cascading failure due to database over- for testing the resiliency of these applications in production in- 2014 [18] load frastructures. We present Gremlin, a framework for systemat- Spotify, Several Cascading failure due to degradation of a ically testing the failure-handling capabilities of microservices. 2013 [26] hours core internal service Gremlin is based on the observation that microservices are Twilio, 10 hours Database failure caused billing service to loosely coupled and thus rely on standard message-exchange 2013 [28] repeatedly bill customers patterns over the network. Gremlin allows the operator to TABLE 1: A subset of recent outages experienced by popular, easily design tests and executes them by manipulating inter- highly available Internet services. Postmortem reports revealed service messages at the network layer. We show how to use missing or faulty failure-handling logic.
    [Show full text]
  • Testing Microservice Applications
    Dmitrii Savchenko TESTING MICROSERVICE APPLICATIONS ACTA UNIVERSITATIS LAPPEENRANTAENSIS 868 Dmitrii Savchenko TESTING MICROSERVICE APPLICATIONS Thesis for the degree of Doctor of Science (Technology) to be presented with due permission for public examination and criticism in the Auditorium of the Student Union House at Lappeenranta-Lahti University of Technology LUT, Lappeenranta, Finland on the 18th of October, 2019, at noon. The thesis was written under a joint doctorate agreement between Lappeenranta-Lahti University of Technology LUT, Finland and South Ural State University, Russia and jointly supervised by supervisors from both universities. Acta Universitatis Lappeenrantaensis 868 Supervisors Adjunct Professor Ossi Taipale LUT School of Engineering Science Lappeenranta-Lahti University of Technology LUT Finland Associate Professor Jussi Kasurinen LUT School of Engineering Science Lappeenranta-Lahti University of Technology LUT Finland Associate Professor Gleb Radchenko School of Electrical Engineering and Computer Science Department of System Programming Federal State Autonomous Educational Institution of High Education South Ural State University (National Research University) Russian Federation Reviewers Professor Timo Mantere Dept. of Electrical Engineering and Automation University of Vaasa Finland Professor Markku Tukiainen School of Computing University of Eastern Finland Joensuu Finland Opponent Professor Ita Richardson Lero - The Irish Software Research Centre University of Limerick Ireland ISBN 978-952-335-414-2 ISBN 978-952-335-415-9 (PDF) ISSN 1456-4491 ISSN-L 1456-4491 Lappeenranta-Lahti University of Technology LUT LUT University Press 2019 Abstract Dmitrii Savchenko Testing microservice applications Lappeenranta, 2019 59 p. Acta Universitatis Lappeenrantaensis 868 Diss. Lappeenranta-Lahti University of Technology LUT ISBN 978-952-335-414-2, ISBN 978-952-335-415-9 (PDF), ISSN-L 1456-4491, ISSN 1456- 4491 Software maintenance costs are growing from year to year because of the growing soft- ware complexity.
    [Show full text]
  • AN INSIGHT INTO MICROSERVICES TESTING STRATEGIES Arvind Sundar, Technical Test Lead
    WHITE PAPER AN INSIGHT INTO MICROSERVICES TESTING STRATEGIES Arvind Sundar, Technical Test Lead Abstract The ever-changing business needs of the industry necessitate that technologies adopt and align themselves to meet demands and, in the process of doing so, give rise to newer techniques and fundamental methods of architecture in software design. In the context of software design, the evolution of “microservices” is the result of such an activity and its impact percolates down to the teams working on building and testing software in the newer schemes of architecture. This white paper illustrates the challenges that the testing world has to deal with and the effective strategies that can be envisaged to overcome them while testing for applications designed with a microservices architecture. The paper can serve as a guide to anyone who wants an insight into microservices and would like to know more about testing methodologies that can be developed and successfully applied while working within such a landscape. Introduction Microservices attempt to streamline the key; as is a good knowledge of how to go software architecture of an application about testing at each stage of the test life by breaking it down into smaller units cycle. More often than not, the traditional surrounding the business needs of methods of testing have proven to be the application. The benefits that are ineffective in an agile world where changes expected out of doing so include creating are dynamic. The inclusion of independent systems that are more resilient, easily micro-units that have to be thoroughly scalable, flexible, and can be quickly and tested before their integration into the independently developed by individual larger application only increases the sets of smaller teams.
    [Show full text]
  • AWS Prescriptive Guidance Enabling Data Persistence in Microservices AWS Prescriptive Guidance Enabling Data Persistence in Microservices
    AWS Prescriptive Guidance Enabling data persistence in microservices AWS Prescriptive Guidance Enabling data persistence in microservices AWS Prescriptive Guidance: Enabling data persistence in microservices Copyright © Amazon Web Services, Inc. and/or its affiliates. All rights reserved. Amazon's trademarks and trade dress may not be used in connection with any product or service that is not Amazon's, in any manner that is likely to cause confusion among customers, or in any manner that disparages or discredits Amazon. All other trademarks not owned by Amazon are the property of their respective owners, who may or may not be affiliated with, connected to, or sponsored by Amazon. AWS Prescriptive Guidance Enabling data persistence in microservices Table of Contents Introduction ...................................................................................................................................... 1 Targeted business outcomes ........................................................................................................ 2 Patterns for enabling data persistence .................................................................................................. 3 Database-per-service pattern ....................................................................................................... 3 API composition pattern ............................................................................................................. 5 CQRS pattern ...........................................................................................................................
    [Show full text]
  • Finding Flexibility with Microservices, Containers, and Runtimes Featuring Research from Forrester How to Capture the Benefits of Microservice Design 2
    Finding Flexibility with Microservices, Containers, and Runtimes FEATURING RESEARCH FROM FORRESTER How To Capture The Benefits Of Microservice Design 2 Finding Flexibility with Microservices, Containers, and Runtimes FINDING FLEXIBILITY WITH MICROSERVICES, CONTAINERS, AND RUNTIMES An introduction to the Forrester analyst report: How to Capture the Benefits of Microservice Design There has always been a relationship between an application and the platform and services which run it. For a long time, that relationship was very tight and encompassed a lot of areas related to the IN THIS application design, from the language the application could be written in to administrative behaviors DOCUMENT like monitoring and logging, even things like transaction management, frontend UI development, or integration methods. 1 Finding Flexibility with Microservices, In a sense, the application platform was just another design consideration for the application. A few Containers, and years ago, as significant changes in platform technology like cloud, containers, and virtual machines Runtimes started rolling out, the primary emphasis for CTOs and application architects was on how to move to those platforms. The platform choice was a major part of the application. The focus was — one way or 5 How To Capture The Benefits Of another — getting into “the cloud.” Microservice Design There’s been a shift in customers’ priorities over the last few years. A 2016 survey of IT professionals by Red Hat found that fewer than 25% of respondents were actually focusing on moving applications 22 About redhat. to the cloud — the majority were focused on writing new applications or maintaining existing ones. The focus is moving from platform to the application itself.
    [Show full text]
  • Microsurfaces: the Role of Apis in a Microservice Architecture
    Microsurfaces: The Role of APIs in a Microservice Architecture 1 1 Microservices Adoption Continues to Grow in All Industries According to a recent survey, 86 percent of respondents expect microservice architecture to be their default approach to building software systems within five years. There are many reasons for moving to a microservice architecture, from increasing delivery speed to improving evolvability and scalability. However, there are also potential pitfalls as complexity shifts from place to place in the system and the associated organizational landscape. As a result, organizations moving to a microservice architecture need tools and techniques to help them deal with these new challenges. When it comes to microservice technologies, people have called containers the “gateway drug to microservices,” and containers can certainly ease deployment and operability. However, API-based communication may be even more vital to delivering value in all aspects of a microservice architecture. This ebook explores the varied roles that APIs play in the microservices landscape. 2 APIs vs. Microservices Before analyzing the value of APIs in a microservice architecture, it helps to clear up It is important to remember any confusion between the definitions of APIs and microservices. When someone says they are “building an API,” they are likely developing a microservice with an API that the API is just the interface, front door. Conversely, there are some who refer to API facades for legacy services as and even more important to microservices. Both examples blur the lines between the terms. remember that the service What is an API? What is a microservice? consumer views the API as a • An application interface exposedon a • An independently deployable contract, and they don’t care network application component what’s behind it as long as they • Can use many styles (e.g., REST), • Often self-contained (e.g., interface, get what they need.
    [Show full text]