Introduction to Fabric Composer

Transcription

1 Introduction to Fabric Composer Anthony O Dowd IBM Corporation IBM Corporation Page 1

2 Contents Concepts & Modelling Applications & Tools Integrating Existing Systems IBM Corporation IBM Corporation Page 2

3 Blockchain Recap Blockchain builds on basic business concepts Business Networks connect businesses Participants with Identity Assets flow over business networks Transactions describe asset exchange Contracts underpin transactions The ledger is a log of transactions Blockchain is a shared, replicated ledger Consensus, immutability, finality, provenance Page 3

4 What is Fabric Composer? Blockchains typically provide a low-level interface for business applications Smart contract code run on a distributed processing system Inputs go into an immutable ledger; outputs to a data store Applications are built on top of a low level of abstraction Fabric Composer A suite of high level application abstractions for business networks Emphasis on business-centric vocabulary for quick solution creation Business Application Fabric Composer Features Model YOUR business networks, test and expose via APIs Applications invoke APIs transactions to interact with business network Integrate existing systems of record using loopback/rest Hyperledger Fabric Tools, APIs and libraries to support these activities Open community initiative in support of the Linux Foundation Hyperledger project Page 4

5 An Example Business Network Existing system Owner App "$class": "org.acme.vehicle.auction.vehicle", "vin": "VIN_123456", "owner": Owner sell car "$class": "org.acme.vehicle.auction.vehiclelisting", "listingid": "LIST_1234", "reserveprice": 500, "description": "Car sale for playback 2", "state": "FOR_SALE", "vehicle": "VIN_123456" Auctioneer App close bidding offer bid for car App Buyer Business Network Participants Identity Assets Registries Transactions (Events) (Links) net.biz.vehicle.auction Vehicle registry Transactions (Sell) Offer Close Bidding Listings registry offer bid for car 2 builds on Buyer ( Counterparties outside the business network ) Insurer DMV Page 5 With FABRIC COMPOSER 1. Model, test and expose the business network 2. Create apps that consuming the business network 3. Integrating existing systems with the business network

6 Benefits of Fabric Composer Increases understanding Saves time Reduces risk Increases flexibility Bridges simply from business concepts to blockchain Develop blockchain applications more quickly and cheaply Well tested, efficient design conforms to best practice Higher level abstraction makes it easier to iterate Page 6

7 Extensive, Familiar, Open Development Toolset composer-client composer-admin Data modelling JavaScript business logic Web playground Client libraries $ composer Editor support CLI utilities Code generation Integration 7

8 Key Concept: Business Network Business network models participants, assets, registries, transactions Includes expressive syntax such as arrays, enumerations and references Transaction processors implement business logic on these model elements Uses standard Javascript for ease of development and portability Access Control Lists define rules for sharing and privacy In Fabric Composer, a business network is defined as A model definition file A set of Javascript processors An Access Control List Packaged into Business Network Archive for ease of deployment Page 8

9 Modelling Business Networks: Composer-UI A modelling environment for modelling, testing, and exposing business networks Aimed at technical analysts Model assets, participants, transactions and more interactively Content assist, syntax checking AND standalone execution Connect and deploy to multiple different environments, e.g. test, production Page 9

10 Key Concept: Assets 1 2 Represents the resources being exchanged in the business network 1. Define using the asset keyword 3 2. Assets have structure domain relevant class name, e.g. vehicle, house, bond 4 3. Set of properties, denoted by o. Relationships to other resources, denoted by. Optional elements are allowed. Field validators can be provided 5 4. Stored in an asset registry. Registries are first class abstraction. Page 10

11 Key Concept: Participants 1 2 Represents the counterparties in the business network 3 1. Define using the participant keyword 2. Participants have a class name, relevant to the domain, e.g. buyer, seller 3. Set of properties, denoted by o. Relationships to other resources, denoted by. Optional elements are allowed. Field validators can be provided 4 4. Stored in a participant registry Page 11

12 Key Concept: Transactions 1 2 Represents the steps that govern resource lifecycle, typically assets 3 1. Define using the transaction keyword 2. Assets have a class name, relevant to the domain, e.g. sellvehicle, buyhouse 3. Set of properties, denoted by o. Relationships to other resources, denoted by. Field validators can be provided 4 4. Stored in a transaction registry Page 12

13 Key Concept: Transaction Processors Provide the implementations for transactions Perform state changes on domain specific resources using model defined syntax Provided in separate.js file. Uses model definitions from CTO file Will result in invocation point from applications, via REST Page 13

14 Contents Concepts & Modelling Applications & Tools Integrating Existing Systems 2017 IBM Corporation 2017 IBM Corporation Page 14

15 Applications and APIs Initially provide node.js programming language due to ecosystem and skills Programming language not tied to node.js, others as need arises composer-client & composer-admin npm modules for app devs and admins respectively Programming model JSDOC at Domain specific REST APIs also available (see later) Page 15

16 Generating Application Assets Modelling approach facilitates skeleton application generation Yeoman questionnaire-based. yo fabric-composer[:angular] Generates sample application from models and network which exploits REST APIs for domain resources Can exercise domain REST APIs from web UI with :angular option Also generate test cases using mocha and chai node.js test packages Page 16

17 Access Control Lists Separate ACL from application logic Defined in a permissions.acl file in business network definition Flexible model allowing both type and instance access e.g. create cars and scrap my car NOUNS can be any type or instance in the model, including transactions PREDICATE allows sophisticated description of access rights Page 17 ID NOUN VERB PARTICIPANT PREDICATE ACTION ID = Default NOUN = org.acme.car VERB = READ PARTICIPANT = ANY PREDICATE = (true) ACTION = allow Anyone can read car assets ID = SallyCarRule NOUN = org.acme.car#abc123 VERB = WRITE PARTICIPANT = org.acme.driver#sally:s PREDICATE = (org.acme.owner = s) ACTION = allow Only Sally can update her car when she owns it

18 Command Line Interfaces $> composer help Suite of commands to interact with an operational business network Commands: archive <subcommand> Composer archive command generator <subcommand> Composer generator command identity <subcommand> Composer identity command network <subcommand> Composer network command participant <subcommand> Composer participant command transaction <subcommand> Composer transaction command Target use is scripting and interactive operations Options: --help Show help [boolean] -v, --version Show version number [boolean] Packaged as composer-cli in npm Examples: composer identity issue For more information: $> composer transaction submit help Generate full list with composer help. Individual (sub) commands support -help Uses public APIs Page 18 composer transaction submit [options] Options: --help Show help [boolean] -v, --version Show version number [boolean] --connectionprofilename, -p The connection profile name [string] --businessnetworkname, -n The business network name [string] [required] --enrollid, -i The enrollment ID of the user [string] [required] --enrollsecret, -s The enrollment secret of the user [string] --data, -d Transactions JSON object [string] [required]

19 Simple Application Development Lifecycle Install Fabric Composer Tools Define Business Network, Assets and Transactions Implement any transaction processors Test business network within Composer-UI Deploy business network to live Hyperledger fabric Generate sample application for this network Test sample application (REST, node.js, ) Strong basis to start your application experience Page 19

20 Contents Concepts & Modelling Applications & Tools Integrating Existing Systems 2017 IBM Corporation 2017 IBM Corporation Page 20

21 Loopback and REST Support Exploit Loopback framework to create REST APIs. Domain specific APIs very attractive to mobile and web developers. Resources and operations are business-meaningful Extensive test facilities for REST methods Provides back-end integration with any loopback compatible product e.g. IBM Integration Bus, API Connect, StrongLoop Outbound notification, an objective Page 21

22 Other Items of Note Extensive use of GitHub and npm for sharing and distribution Fabric Composer, User Models, User network definitions Semantic versioning of networks and models using npm versions Intention to add query, events and links as first class abstractions Extensive query to support reporting and analytics Events for notification and loose coupling of transaction processors Links for business network linkage More sample applications to demonstrate Fabric composer Includes sample-models and sample-networks (labs this week) Community Building and Community Process: Transparency Page 22

23 Summary Building blockchain apps Get started with Fabric Composer Fabrics designed for technologists Play with blockchain on Composer Playground makes adoption simple Dozens of decisions relating to web interface, application server, blockchain resource management etc. Everything built from scratch which is time-intensive and error prone. Page 23 Learn syntax basics, how to model data, build assets, submit transactions Run applications with pre-built best practices in a public or privately managed environment. Integrate with existing systems.

24 Thank you! 2016 IBM Corporation 2017 IBM Corporation Page 24