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Basic principles of ChainlinkIn this paper, we will briefly introduce the basic principle of Chainlink. If we use the shortest sentence to explain what Chainlink is, we can say that Chainlink is a decentralized Oracle project, so in order to understand the working principle of Chainlink, we should first understand what is a oracle. Prophecy mac ...

Previous article: Build your first blockchain network (3) UTXO component UTXO is an important concept in bitcoin. In this section, we will implement a simple UTXO. We divide the components of UTXO into the following three points: UTXOId: identify the UTXO TxInput: transaction input, i.e. input address and amount of coin TxOutput: ...

Let's continue with the following simple policy example to learn how to operate multiple targets in a policy. def initialize(context): context.security = 'BTC/USDT.binance' context.myaccount = context.get_account('myaccount') def handle_data(context): current_pric ...

Preface With the development of blockchain technology, more and more enterprises and individuals begin to combine blockchain with their own business. The unique advantages of blockchain, such as transparent and tamper proof data, can bring convenience to business. But at the same time, there are some hidden dangers. The data is open and transp ...

Simple voting DApp Next, we will start to make a DApp. Although it is a very simple voting application, it will contain a complete workflow and interaction page. The main steps to build this application are as follows: We first install an analog blockchain called ganache, which can let our program run in the development environment. Writ ...

A new feature introduced in Hyperledger Fabric 2.0 is the ability to use external chain code launchers, which are ideal for using kubenetes or dowcker swarm to manage node and chain code containers in a unified manner.In this article, we will learn how to deploy chain codes in a K8s cluster using an external chain code launcher. 1. Prerequisite ...

Article directory Introduction to ICO crowdfunding Crowdfunding contract initialization Crowdfunding contract realization Introduction to ICO crowdfunding ICO (initial crypto token offering, first token crowdfunding) is considered to be a new type of investment and financing mode generated by th ...

This article is based on fabric v2.0.1 The initialization process of localmsp and bccsp is described with the example of peer node startup. I. BCCSP BCCSP is the abbreviation of Blockchain Cryptographic Service Provider, which is an abstract representation of commonly used block chain cryptography al ...

introduce Whether mysql or mongodb, the traditional way to interact with database is to write code according to the API they provide. The APIs they provide are often not easy to understand and hard to remember. If you pass wrong parameters and write a wrong symbol, you need to check the document. The ORM (Object Relational Mapping) framework ...

Why is it called a thermostat. We name the system according to its ability to adapt to market, shock and trend. The system comes from our observation of the success of a particular system in a particular market area. This system can create dual strategies to make full use of the two models of the market. First, we create a function to help ...