Hands-On Blockchain for Python Developers : Gain Blockchain Programming Skills to Build Decentralized Applications Using Python

Implement real-world decentralized applications using Python, Vyper, Populus, and Ethereum Key Features Stay up-to-date with everything you need to know about the blockchain ecosystem Implement smart contracts, wallets, and decentralized applications(DApps) using Python libraries Get deeper insights into storing content in a distributed storage platform Book Description Blockchain is seen as the main technological solution that works as a public ledger for all cryptocurrency transactions. This book serves as a practical guide to developing a full-fledged decentralized application with Python to interact with the various building blocks of blockchain applications. Hands-On Blockchain for Python Developers starts by demonstrating how blockchain technology and cryptocurrency hashing works. You will understand the fundamentals and benefits of smart contracts such as censorship resistance and transaction accuracy. As you steadily progress, you'll go on to build smart contracts using Vyper, which has a similar syntax to Python. This experience will further help you unravel the other benefits of smart contracts, including reliable storage and backup, and efficiency. You'll also use web3.py to interact with smart contracts and leverage the power of both the web3.py and Populus framework to build decentralized applications that offer security and seamless integration with cryptocurrencies. As you explore later chapters, you'll learn how to create your own token on top of Ethereum and build a cryptocurrency wallet graphical user interface (GUI) that can handle Ethereum and Ethereum Request for Comments (ERC-20) tokens using the PySide2 library. This will enable users to seamlessly store, send, and receive digital money. Toward the end, you'll implement InterPlanetary File System (IPFS) technology in your decentralized application to provide a peer-to-peer filesystem that can store and expose media. By the end of this book, you'll be well-versed in blockchain programming and be able to build end-to-end decentralized applications on a range of domains using Python. What you will learn Understand blockchain technology and what makes it an immutable database Use the features of web3.py API to interact with the smart contract Create your own cryptocurrency and token in Ethereum using Vyper Use IPFS features to store content on the decentralized storage platform Implement a Twitter-like decentralized application with a desktop frontend Build decentralized applications in the shape of console, web, and desktop applications Who this book is for If you are a Python developer who wants to enter the world of blockchain, Hands-On Blockchain for Python Developers is for you. The book will be your go-to guide to becoming well-versed with the blockchain ecosystem and building your own decentralized applications using Python and library support. Table of Contents Introduction to Blockchain Programming Smart Contract Fundamentals Implementing Smart Contract Using Vyper Interacting With Smart Contract Using Web3 Populus Development Framework Building a Practical Decentralized Application Front-end Decentralized Application Creating Token in Ethereum Cryptocurrency Wallet Inter Planetary: A Brave New File System Using Py-ipfs-api to Connect to Decentralized File System Implementing Decentralized Application Using IPFS Cover Title Page Copyright and Credits About Packt Foreword Contributors Table of Contents Preface Section 1: Blockchain and Smart Contracts Chapter 1: Introduction to Blockchain Programming The rise of cryptocurrency and blockchain Blockchain technology Signing data in blockchain From linked list to blockchain Cryptography Symmetric and asymmetric cryptography The hashing function Proof of work Consensus Coding on the blockchain Other types of blockchain programmers Summary References Chapter 2: Smart Contract Fundamentals Installing an Ethereum development environment Installing Node.js Installing Truffle and Solidity Installing Ganache Writing a smart contract Deploying a smart contract to Ethereum blockchain Interacting with smart contracts Sending ether to smart contracts Why smart contracts? Summary Further reading Chapter 3: Implementing Smart Contracts Using Vyper Motivations behind Vyper Installing Vyper Creating a smart contract with Vyper Deploying a smart contract to Ganache Interacting with smart contracts Going deeper into Vyper Data types Withdrawing ethers Other data types Useful built-in functions Events Interacting with other smart contracts Compiling code programmatically Other tricks Summary Section 2: Web3 and Populus Chapter 4: Interacting with Smart Contracts Using Web3 Introduction to decentralized applications Installing web3 Geth Geth console Understanding the web3.py library Gas and gas price Nonce Creating a transaction on Rinkeby Interacting with smart contracts using web3.py Launching a smart contract with Geth Launching a smart contract with web3 Playing with a smart contract Summary Chapter 5: Populus Development Framework Setting up Populus Adding support for Vyper Smart contract unit test Using arguments in the constructor Deploying a smart contract with Populus Summary Chapter 6: Building a Practical Decentralized Application Developing a simple voting application Deploying a smart contract that has arguments in its constructor Developing a commercial voting application Developing a token-based voting application Summary Further reading Section 3: Frontend Decentralized Applications Chapter 7: Frontend Decentralized Application Setting up the Qt GUI library Choosing a GUI library Installing Qt for Python Crash course on Qt for Python Layout Other widgets Callback Threading Writing the smart contract for the Twitter–like application Test Fixtures Building the GUI frontend for the Twitter–like application Summary Section 4: Cryptocurrency and Wallets Chapter 8: Creating Token in Ethereum Token smart contract Mist ERC20 Selling a token Stable coin Summary Further reading Chapter 9: Cryptocurrency Wallet Advanced features of the PySide2 library Testing application Advanced features of Qt for Python or PySide2 Building a cryptocurrency wallet Blockchain class Thread classes Identicon and Icons Building widgets Account widget Sending a transaction widget Token widget Test Considerations when building a cryptocurrency wallet Security User experience Summary Section 5: Decentralized Filesystem Chapter 10: InterPlanetary - A Brave New File System The motivation behind IPFS Merkle DAG Merkle tree Directive Acrylic Graphs (DAGs) Content addressing The Merkle DAG data structure Peer-to-peer networking The notion of closeness of data and nodes XOR distance Buckets Summary Chapter 11: Using ipfsapi to Interact with IPFS Installing the IPFS software and its library Content hashing Protobuf Multihash Base58 Combining protobuf, multihash, and base58 The ipfsapi API IPNS Pinning Pubsub Mutable File System Other APIs Summary Further reading Chapter 12: Implementing a Decentralized Application Using IPFS Architecture of the decentralized video-sharing application Architecture of a video-sharing smart contract Architecture of a video-sharing web application Writing the video-sharing smart contract Launching a private Ethereum blockchain Creating a bootstrap script Building the video-sharing web application Views Models Templates Urls Demo Note Summary Further reading Other Books You May Enjoy Index **Implement real-world decentralized applications using Python, Vyper, Populus, and Ethereum** ## Key Features * Stay up-to-date with everything you need to know about the blockchain ecosystem * Implement smart contracts, wallets, and decentralized applications(DApps) using Python libraries * Get deeper insights into storing content in a distributed storage platform ## Book Description Blockchain is seen as the main technological solution that works as a public ledger for all cryptocurrency transactions. This book serves as a practical guide to developing a full-fledged decentralized application with Python to interact with the various building blocks of blockchain applications. Hands-On Blockchain for Python Developers starts by demonstrating how blockchain technology and cryptocurrency hashing works. You will understand the fundamentals and benefits of smart contracts such as censorship resistance and transaction accuracy. As you steadily progress, you'll go on to build smart contracts using Vyper, which has a similar syntax to Python. This experience will further help you unravel the other benefits of smart contracts, including reliable storage and backup, and efficiency. You'll also use web3.py to interact with smart contracts and leverage the power of both the web3.py and Populus framework to build decentralized applications that offer security and seamless integration with cryptocurrencies. As you explore later chapters, you'll learn how to create your own token on top of Ethereum and build a cryptocurrency wallet graphical user interface (GUI) that can handle Ethereum and Ethereum Request for Comments (ERC-20) tokens using the PySide2 library. This will enable users to seamlessly store, send, and receive digital money. Toward the end, you'll implement InterPlanetary File System (IPFS) technology in your decentralized application to provide a peer-to-peer filesystem that can store and expose media. By the end of this book, you'll be well-versed in blockchain programming and be able to build end-to-end decentralized applications on a range of domains using Python. ## What you will learn * Understand blockchain technology and what makes it an immutable database * Use the features of web3.py API to interact with the smart contract * Create your own cryptocurrency and token in Ethereum using Vyper * Use IPFS features to store content on the decentralized storage platform * Implement a Twitter-like decentralized application with a desktop frontend * Build decentralized applications in the shape of console, web, and desktop applications ## Who this book is for If you are a Python developer who wants to enter the world of blockchain, Hands-On Blockchain for Python Developers is for you. The book will be your go-to guide to becoming well-versed with the blockchain ecosystem and building your own decentralized applications using Python and library support. 1. Introduction to Blockchain Programming 2. Smart Contract Fundamentals 3. Implementing Smart Contract Using Vyper 4. Interacting With Smart Contract Using Web3 5. Populus Development Framework 6. Building a Practical Decentralized Application 7. Front-end Decentralized Application 8. Creating Token in Ethereum 9. Cryptocurrency Wallet 10. Inter Planetary: A Brave New File System 11. Using Py-ipfs-api to Connect to Decentralized File System 12. Implementing Decentralized Application Using IPFS Learn the foundations of blockchain technology - its core concepts and algorithmic solutions across cryptography, peer-to-peer technology, and game theory.Key FeaturesLearn the core concepts and foundations of the blockchain and cryptocurrenciesUnderstand the protocols and algorithms behind decentralized applicationsMaster how to architect, build, and optimize blockchain applicationsBook DescriptionBlockchain technology is a combination of three popular concepts: cryptography, peer-to-peer networking, and game theory. This book is for anyone who wants to dive into blockchain from first principles and learn how decentralized applications and cryptocurrencies really work.This book begins with an overview of blockchain technology, including key definitions, its purposes and characteristics, so you can assess the full potential of blockchain. All essential aspects of cryptography are then presented, as the backbone of blockchain. For readers who want to study the underlying algorithms of blockchain, you'll see Python implementations throughout.You'll then learn how blockchain architecture can create decentralized applications. You'll see how blockchain achieves decentralization through peer-to-peer networking, and how a simple blockchain can be built in a P2P network. You'll learn how these elements can implement a cryptocurrency such as Bitcoin, and the wider applications of blockchain work through smart contracts. Blockchain optimization techniques, and blockchain security strategies are then presented. To complete this foundation, we consider blockchain applications in the financial and non-financial sectors, and also analyze the future of blockchain. A study of blockchain use cases includes supply chains, payment systems, crowdfunding, and DAOs, which rounds out your foundation in blockchain technology.What you will learnThe core concepts and technical foundations of blockchainThe algorithmic principles and solutions that make up blockchain and cryptocurrenciesBlockchain cryptography explained in detailHow to realize blockchain projects with hands-on Python codeHow to architect the blockchain and blockchain applicationsDecentralized application development with MultiChain, NEO, and EthereumOptimizing and enhancing blockchain performance and securityClassical blockchain use cases and how to implement themWho this book is forThis book is for anyone who wants to dive into blockchain technology from first principles and build a foundational knowledge of blockchain. Familiarity with Python will be helpful if you want to follow how the blockchain protocols are implemented. For readers who are blockchain application developers, most of the applications used in this book can be executed on any platform. Implement decentralized blockchain applications to build scalable Dapps Key Features Understand the blockchain ecosystem and its terminologies Implement smart contracts, wallets, and consensus protocols Design and develop decentralized applications using Bitcoin, Ethereum, and Hyperledger Book Description The Blockchain is a revolution promising a new world without middlemen. Technically, it is an immutable and tamper-proof distributed ledger of all transactions across a peer-to-peer network. With this book, you will get to grips with the blockchain ecosystem to build real-world projects. This book will walk you through the process of building multiple blockchain projects with different complexity levels and hurdles. Each project will teach you just enough about the field's leading technologies, Bitcoin, Ethereum, Quorum, and Hyperledger in order to be productive from the outset. As you make your way through the chapters, you will cover the major challenges that are associated with blockchain ecosystems such as scalability, integration, and distributed file management. In the concluding chapters, you'll learn to build blockchain projects for business, run your ICO, and even create your own cryptocurrency. Blockchain by Example also covers a range of projects such as Bitcoin payment systems, supply chains on Hyperledger, and developing a Tontine Bank Every is using Ethereum. By the end of this book, you will not only be able to tackle common issues in the blockchain ecosystem, but also design and build reliable and scalable distributed systems. What you will learn Grasp decentralized technology fundamentals to master blockchain principles Build blockchain projects on Bitcoin, Ethereum, and Hyperledger Create your currency and a payment application using Bitcoin Implement decentralized apps and supply chain systems using Hyperledger Write smart contracts, run your ICO, and build a Tontine decentralized app using Ethereum Implement distributed file management with blockchain Integrate blockchain into existing systems in your organization Who this book is for If you are keen on learning how to build your own blockchain decentralized applications from scratch, then this book is for you. It explains all the basic concepts required to develop intermediate projects and will teach you to implement the building blocks of a blockchain ecosystem. Downloading the example code for this book You can download the example code files for all Packt books you hav .. Learn the foundations of blockchain technology - its core concepts and algorithmic solutions across cryptography, peer-to-peer technology, and game theory. Key Features Learn the core concepts and foundations of the blockchain and cryptocurrencies Understand the protocols and algorithms behind decentralized applications Master how to architect, build, and optimize blockchain applications Book Description Blockchain technology is a combination of three popular concepts: cryptography, peer-to-peer networking, and game theory. This book is for anyone who wants to dive into blockchain from first principles and learn how decentralized applications and cryptocurrencies really work. This book begins with an overview of blockchain technology, including key definitions, its purposes and characteristics, so you can assess the full potential of blockchain. All essential aspects of cryptography are then presented, as the backbone of blockchain. For readers who want to study the underlying algorithms of blockchain, you'll see Python implementations throughout. You'll then learn how blockchain architecture can create decentralized applications. You'll see how blockchain achieves decentralization through peer-to-peer networking, and how a simple blockchain can be built in a P2P network. You'll learn how these elements can implement a cryptocurrency such as Bitcoin, and the wider applications of blockchain work through smart contracts. Blockchain optimization techniques, and blockchain security strategies are then presented. To complete this foundation, we consider blockchain applications in the financial and non-financial sectors, and also analyze the future of blockchain. A study of blockchain use cases includes supply chains, payment systems, crowdfunding, and DAOs, which rounds out your foundation in blockchain technology. What you will learn The core concepts and technical foundations of blockchain The algorithmic principles and solutions that make up blockchain and cryptocurrencies Blockchain cryptography explained in detail How to realize blockchain projects with hands-on Python code How to architect the blockchain and blockchain applications Decentralized application development with MultiChain, NEO, and Ethereum Optimizing and enhancing blockchain performance and security Classical blockchain use cases and how to implement them Who this book is for This book is for anyone who wants to dive into blockchain technology from first principles and build a .. What You Will Learn * Cryptography and foundation for Blockchain * The role of cryptographic algorithms and decentralized computing in Blockchain * Understanding the Blockchain, transactions and decentralization in cryptocurrency * Architecting and implementing decentralized Blockchain application with few use cases * Security, enhancement and optimization of Blockchain application * Depth comparison of Blockchain application categories and how to choose a Blockchain use case In Detail Blockchain and cryptocurrencies like Bitcoin have hogged the headlines for a long time. But after the hype and the money, there is a lot of technical work to be done, and developers in particular need to understand in some depth what foundations they are actually building their project on. There is quite a bit of cryptography which we have to understand, and the general security in p2p networking demands of Blockchain, before diving into the first Blockchain project All these concepts are explained by building simple applications from scratch. Cryptocurrencies and decentralized applications are extremely popular, but not well understood technically, which is why Koshik Raj is presenting two of the core chapters of the book dedicated to both topics. Koshik Raj then compares the Blockchain application categories, which helps to choose a blockchain use case, followed by a chapter on how to optimize and enhance a Blockchain application. Security is always a concern in decentralized application, which is why a dedicated chapter will try to address all the visible concerns in the blockchain technology space and help to build a secure blockchain app. Finally, Koshik Raj shows us how to branch out into new territory, and which rules and observations to take into account when doing your own Blockchain R&D Learning the Algorithms and Protocols underlying Blockchain before Undertaking Blockchain Projects About This Book * Explains all networking and cryptography inherent in Blockchain by creating simple applications * Talks about the theory as well as the nuts and bolts of blockchain applications and cryptocurrencies * Leads to the frontiers of Blockchain extensions and new application areas Who This Book Is For Readers should be comfortable with general security terms, but no knowledge of cryptography or decentralized application is assumed. Although the book begins with all the basic concepts, a hands-on python programming, and theoretical networking knowledge, would speed up the reading process This book is for Python developers to implement various components of end-to-end decentralized applications such as cryptocurrencies, smart contracts, wallet and more. You will use the example-based approach using various libraries from Python ecosystem to build efficient and powerful blockchain applications at work or projects.