Total number of fabric blockchain settings
a total of 22 weeks, divided into five stages,
the first stage is 4 weeks, go language foundation and network concurrency, learning the introctory go language,
the second stage is 4 weeks, go language practical web development, crawler development, cryptography, consensus algorithm, realizing lightweight public chain, learning the website and crawler that can develop golang, Achieve lightweight blockchain
stage 3, 4-week Ethereum source code analysis and smart contract DAPP development, master Ethereum core and smart contract development, as well as blockchain,
stage 4, 4-week super ledger, bitcoin EOS, source code analysis and smart contract practice, master super ledger development, cat bitcoin, bifurcated EOS after learning, As well as DAPP development of smart contract
phase 5, 6-week project practice, five enterprise level projects, and one year of blockchain project experience after learning
from the characteristics of the language itself, go is a very efficient language, which highly supports concurrency. Go language itself pays more attention to distributed system, and concurrency processing is relatively good, such as advertising and search, That kind of high concurrency server
go language advantages:
excellent performance, can be directly compiled into machine code, does not rely on other libraries, go is extremely fast. Its performance is similar to Java or C + +
concurrency is supported at the language level, which is the biggest feature of go. It is born to support concurrency, and go is the concurrency supported in gene, which can make full use of multi-core and make it easy to use concurrency
the built-in runtime supports garbage collection, which is one of the features of dynamic language. Although GC is not perfect at present, it is enough to cope with most of the situations we can encounter, especially GC after go1.1
it's easy to learn. The authors of go language all have the gene of C, so go naturally has the gene of C. There are 25 go keywords, but the expressive ability is very strong. It almost supports most of the features you've seen in other languages: inheritance, overloading, object, etc
rich standard libraries, go has built a large number of libraries, especially the network library, which is also my favorite part< As like as two peas, br / > built-in powerful tools, Go language is built with many tools chain, the best should be gofmt tools, automatic formatting code, make team review become so simple, code format is exactly the same, it is very difficult to think differently.
cross platform compilation and fast compilation. Compared with the sluggish compilation speed of Java and C + +, the fast compilation time of go is a major efficiency advantage
disadvantages of go language:
package management: package management of go language is absolutely not perfect. By default, it has no way to make a specific version of the dependency library, nor can it create replicable builds. In contrast, python, node and Ruby all have better package management systems. However, with the right tools, the package management of go language can also perform well
lack of development framework: go language does not have a major framework, such as Ruby's rails framework, Python's Django framework or PHP's laravel. This is a heated discussion in the go language community, because many people think that we should not start with using frameworks. This is true in many cases, but if you just want to build a simple crud API, it's much easier to use Django / djrf, rails laravel, or Phoenix
exception handling: go language can help developers deal with compilation errors by simply returning errors (or call stack) through functions and expected calling codes. Although this method is effective, it is easy to lose the scope of the error, so it is difficult to provide meaningful error information to users. Error package can solve this problem by allowing us to add context and stack trace to return error
another problem is that we may forget to handle errors. Static analysis tools such as errcheck and megacheck can avoid these errors. Although these solutions are very effective, they may not be the right way.
blockchain is an important concept of bitcoin, which is essentially a decentralized database and the underlying technology of bitcoin. Blockchain is a series of data blocks generated by cryptography. Each data block contains the information of a bitcoin network transaction, which is used to verify the validity of the information (anti-counterfeiting) and generate the next block
let's talk about the social or economic significance of blockchain. In fact, many of the previous technologies were devoted to "proctivity". For example, artificial intelligence is a kind of progress in proctivity. The blockchain, which has greatly improved the proction relations, is committed to the proction relations. So why do you say that
because the so-called proction relationship is actually how to do business between people and business partners. And these things, originally, are in the cognitive process between people, and there is no special program to program or quantify it
for example, if you and I are good friends now, we can do business. If someone stirs up our relationship and we are not good friends, we will not do business. Even if we can make money in business, we will not do business because there is no trust between us
as for blockchain, it is actually because the data is authenticated by all nodes and backed up at the same time, so my data is as real as possible and can't be tampered with. In this case, if you believe my data, you can make a program on this basis, and then use the data to make what kind of business contract, what kind of service, what kind of service, and what kind of service, what kind of service, what kind of service, what kind of service, what kind of service, what kind of service, what kind of service, etc This "proction relationship" of commercial cooperation is programmed. In this way, we believe in the data and the program compiled by the algorithm. Because you believe in the data and the program, you can develop all kinds of apps in the program. These apps are the proction relations and what business to do. This is: blockchain is actually a reconstruction of "proction relationship".
Blockchain is a new application mode of distributed data storage, point-to-point transmission, consensus mechanism, encryption algorithm and other computer technologies. Blockchain is an important concept of bitcoin. It is essentially a decentralized database. At the same time, as the underlying technology of bitcoin, it is a series of data blocks generated by using cryptographic methods. Each data block contains a batch of information about bitcoin network transactions, Used to verify the validity of its information (anti-counterfeiting) and generate the next block
if such technology wants to be put into application, the biggest problem is the "Impossible Triangle problem"
that is, scalability, decentralization and security cannot be achieved at the same time, and only two of them can be achieved
most of the existing public chain projects in the market are difficult to put into use on a large scale
if you look at the problem with the thinking of 30 years ago, you will think that others are crazy, but in fact you are out of date
the concept of blockchain can be traced back to the end of 2008. In the forum, a mysterious personage named "Nakamoto Tsung" published a paper "bitcoin: a peer-to-peer e-cash system" and proposed the concept of blockchain for the first time
on January 3, 2009, the first block of the blockchain was born, which is called the "Founding block"
almost with the birth of blockchain technology, bitcoin became the first thing to play its role. In the following years, bitcoin graally swept the world. In 2017, its crazy market made blockchain technology known to all
the idea of blockchain first appeared in the famous bitcoin open source project. In the process of its birth and development, bitcoin project draws on the technical achievements from digital currency, cryptography, game theory, distributed system, cybernetics and other fields. It can be said that bitcoin project is good at all. As its core supporting structure, blockchain technology is a remarkable innovation achievement
blockchain is a distributed database system with different nodes, which is an open ledger system<
three characteristics of blockchain
compared with the traditional centralized scheme, blockchain technology mainly has the following three characteristics:
the core idea of blockchain is decentralization
in the blockchain system, the rights and obligations between any node are equal, and all nodes have the ability to vote with computing power, Thus, the result recognized by more than half of the nodes is guaranteed. Even under serious hacker attacks, as long as the number of nodes controlled by hackers does not exceed half of the total number of nodes in the world, the system can still operate normally and the data will not be tampered with
block chain's biggest subversive is the establishment of credit
the collective maintenance of blockchain can rece the cost
in the centralized network system, the maintenance and operation of the system depend on the operation and operation of platforms such as data center, and the cost cannot be omitted. Anyone can participate in the nodes of the blockchain. Each node can verify the correctness of the results of other nodes' records while participating in the records, which improves the maintenance efficiency and reces the cost
in a word, blockchain touches money, trust and power, which are the fundamental basis for human survival< Its development has gone through three stages
1. Brewing period: from 2009 to 2012, bitcoin and its instrial ecology are the main economic forms
2. Embryonic period: from 2012 to 2015, with bitcoin entering the public view, new wallet payment and remittance companies appeared, and blockchain economy spread to the financial field. The underlying technology of blockchain is constantly innovated. Blockchain technology is separated from bitcoin system
3. Development period: in 2016, we began to explore instry applications, and a large number of blockchain start-ups appeared. The popularity of ICO in 2017 has given blockchain unprecedented attention
"blockchain 2.0 era" is coming
the application service layer is the driving force for the sustainable development of blockchain, which is divided into three stages of application: 1.0, 2.0 and 3.0
programmable currency: blockchain 1.0 application
programmable currency is the digital currency represented by bitcoin, but it is not the legal tender of any country or region, and there is no government authority to provide guarantee for it
programmable Finance: blockchain 2.0 application& quot; Smart contract& quot; Using program algorithm to replace the concept of contract execution. This enables blockchain to expand from the original monetary system to the registration and transfer of equity, creditor's rights and property rights, the transaction and execution of securities and financial contracts, and even the financial fields of gambling and anti-counterfeiting
programmable Society: blockchain 3.0 application
blockchain is the core of value Internet, which can confirm, measure and store the property rights of information and bytes representing value in each Internet. It can not only record the transactions of the financial instry, but also record almost anything valuable that can be expressed in the form of code. Its application can be extended to any field with demand, and then to the whole society
at present, the application of blockchain has begun to surpass bitcoin (blockchain 1.0), enter the era of blockchain 1.5, and transition to the financial field (blockchain 2.0)
in the next 3-5 years, blockchain may go beyond the financial field and enter the field of social notarization and intelligence (blockchain 3.0), including identity authentication, notarization, arbitration, audit, domain name, logistics, medical care, mail, visa, voting and other fields. Its application scope will be expanded to the whole society, and blockchain technology is likely to become a new technology& quot; All things are connected& quot; It's the lowest level protocol
at present, blockchain technology has been recognized by the world, and its development has become an inevitable trend. Accompanied by more people's attention, "in the next 30 years, new technologies will be integrated into all aspects of traditional instries, and human society will turn upside down. No matter who you are, no matter where you are, all of us will be a part of this great change."
this is the current situation. Blockchain has given the post-90s an opportunity. However, if you want to control blockchain technology without being affected by negative factors, the most important thing is to have a clear understanding of it, whether it is regulators, researchers, speculators or bystanders
it's time to devote more energy to blockchain technology
in China, the average annual salary of blockchain positions has reached more than 300000, and that of some enterprises has reached more than 1 million. The monthly salary of blockchain instry graates in Beijing, Shanghai and other places has exceeded 20K! If the post-90s seize the bonus of the times, they may become the next Alibaba in the future! If you miss it, you may regret it for ten years.
the hypervessel platform developed by IBM China Research Institute provides a blockchain development and testing environment for blockchain enthusiasts and developers. Through this platform, users can create a multi node blockchain based on hyperledger fabric free of charge and quickly, and play smart contracts on their own chains
of course, decent, a foreign decentralized content sharing platform, can also be created.
new gold digger's Chinese version...
game props: press the key to start pulling gold. The red bomb means to pull something you don't want. Press the "↑" key ~ to blow up the thing you pull yourself. The yellow bottle with three forks is strong water. It's a little faster when recycling the rope, It only takes effect in one round. The book "rocks" on it means that if you collect stones, you can sell them at a higher price than usual! 11 pieces of small stones can sell 33 pieces, which is also effective in the same game. The thing in the yellow bottle is brick oil, which will make bricks appreciate. 600 pieces of bricks will sell to 900! It's also the lucky grass that takes effect in the first round. If you use it, you can increase your lucky degree and pull it to "?" If you buy a small bag, you may become very strong, or you may get some of the above items, and sometimes even the price of stones will rise!
Puyin is a high-quality Tibetan tea asset, which is stored, identified, evaluated and authorized by three parties. It is a standard digital currency issued through encryption and digitization. Puyin implements it in strict accordance with the concept of "white paper on standard digital currency" as its operation guideline. It is also a digital currency based on blockchain technology.