Activate the virtual environment
This is a requirement because any change in the python module in the system can affect the whole code. A virtual environment will not cause any such problem to the system modules.
source blockchain-env/bin/activate Installing all the requirements
All the requirements will be updated in the requirements.txt file hence there will not be any requirement of typing numbers of code. Enter the following code in the terminal or command prompt to install the given requirements. Make sure you have pip installed.
pip3 install -r requirements.txt Running tests
Make sure to activate the virtual environment first. Then later perform these tests.
python3 -m pytest backend/tests Running the app and API
Make sure to activate the virtual environment first. Then perform these tests.
python3 -m backend.app Running a peer instance
Make sure to activate the virtual environment.
export PEER=True && python3 -m backend.app This will be updated accordingly
My idea is to create a cryptocurrency system which I can utilise for payments inside the college. The idea is to create a full fledged cryptocurrency system with certain nodes and verification. I hope to make teacher's desktops as miners and students as the wallet holders. Teacher's desktop will verify and add the transaction details to the blockchain and on spending some computational power the teacher may recieve some incentive which will be decided during a later period. The value of the currency system will also be decided later on.
The notes provided are in chronological order. Even the words written are in chronological order.
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Day 1(10/10/2020): Created the blockchain module and block module, also we have created the hashing function in the python-blockchain folder. The files are commented for anyone to understand the code.[END OF DAY 1]
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Day 2(11/10/2020): We have updated our modules into packages, and we have put init.py function each of the folders. We have split the modules into two categories blockchain and util. Blockchain contains the block and blockchain module. Util contains the other utilities required in the function. We have also set up a virtual environment using the venv command and to activate the virtual environment we have used the shell/terminal command mentioned above in this file. So to activate the package format we use
python3 -m backend.blockchain.block We don't need any .py extension to the file as it automatically loads all the folders and stuff.
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I have also created some tests using Pytest. Pytest checks all the test cases at once rather than us have to type test cases inside the python file and then later we have to check cases for each of the files. Later I have also included time.asctime() to display the timestamp in form of string.[END OF DAY 2]
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Day 3(18/10/2020): I have created the proof of work system in the Block.py module in the mine_block() method. I also have included certain tests in the test folder. Now I also have created a config.py file which will give the mention of the MINE_RATE. Now I have set the mine rate to 10 seconds. So we have to get the rate to around 10 seconds (4 seconds just for program purposes). Now we have added certain tests which support the proof of work system. Till now there was a hex based proof of work system but we need a binary form of proof of work system. Now we have implemented a system for conversion of hex to binary and hence the difficulty determination is binary based work now. There is no new shell script other than testing the application. Extra information is given in the required files.
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PART 2: Now I have implemented conditions required for validation of the block and test condtions in the test_block.py file. These tests will check the conditions necessary to validate a block. Also with the help of the pytest's 'with' keyword, we have been able to validate the require exception without the program crashing. Later we have provided test cases to validate a chain, which is basically validating multiple blocks. One important condition is that we have to validate the genesis block which we didn't do in block validation. Hence this was the extra thing we did in the blockchain validation. More stuff is given in programs as documentation string and as well as in commented blocks. Later we have included some chain texts which will help us setup nodes in the blockchain network. Later I will try to explain the use of REST api's and pubsub layers the best I can because I'm using it for the first time myself.[END OF DAY 3]
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Day 4(25/10/2020): I have now setup Flask which is a python module used to create web applications as well as API. The installation of this module is updated in the requirements.txt file. This will install the required modules in the virtual environment. Then later I have been able to run the application which have helped to run this application as localhost. I have also imported the jsonify class to convert objects into JSON format which can be utilised by any application to read data. But then Blockchain class is not JSON serializable hence we need to provide a method in the blockchain class which does so. I have added a method which will return the string to it's JSON format which is either a dictionary, string, tuple, response instance or a valid callable. This ensures that the text in the blockchain gets jsonified and we will get the proper blockchain output in the JSON format which can be utilised by the application to access it's data. Later I also have setup the mine block route in the app directory's init.py file which does the mining method in the server. Later in the day I have installed requests module in python which will help get any peer node the already present blockchain data. This will ensure all the nodes remain upto date in the network.
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Day 5(14/11/2020): Today I began my work with developing a cryptocurrency system in this project. I have started by making a folder for the wallet which has different parameters. A wallet should contain a public key, a private key, transactions and wallet balance. So by python I have created a wallet module (by adding an init file along with the main file.), this features wallet data mentioned above, method for signing transactions as well as verify them. Initially I have imported a UUID module which serves us as a Unique digital identifier, this will help us prevent repeating transactions over the same address. Our method for cryptography is EC(Elliptic cryptography), but soon our team will try to migrate to RSA cryptography. This method is highly complex mathematics and will not be easy to crack the original data once created. I have also updated the requirements.txt file in this folder so that future developers can collaborate into this project by downloading the required files. There are many inbuilt functions in the modules. I have also included a test to verify the wallet data in the tests folder in the backend module.
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Later I have also created a transaction module which facilates the transactions in this cryptocurrency network. This includes the wallet module created and uuid module which provides a unique identifier to the new module. The transactions module contains input structure and output structure which will record and calculate the balance necessities in a wallet. This includes exceeding balance which should result in a failure of transactions. We have also included tests for the transactions which will help us in correcting any error which comes into the code without having to run any programs again and again.
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Day 6 (15/11/2020): Today I have installed another application which will bring us POST requests necessary for carrying out transactions, for that we have refactored some code which has helped in running the application smoothly (serialised public key and signature), I have imported a few encoding and decoding functions which will help convert byte strings to required format (either lists, tuples, dictionaries, strings, or booleans). We have also been able to get the signature values in the form of a tuple using elliptic key Cryptography decoding and encoding functions. The application we are using is POSTMAN (i guess which will not be required in later stages).
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Next I have created a transaction pool which will store the transaction data which will be available for the node to read. Later I am also trying to broadcast transactions by deserialising them back to it's instance which will help read the transaction data and it's output. Later this design will also help in implementation of the frontend mechanics.
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Day 7(16/11/2020): Today our goal was to complete the backend part of our project. This involved linking our cryptocurrency system to our blockchain system. We already have built our blockchain module in it's entirity by taking the data as some test string. This test string is now replaced with the actual transaction data which we require during any transaction activity. We have jsonified this data hence this can be readable accross any websites. We have also performed some test app scripts which will send data in realtime to check whether the application works properly or not. During this process we also encountered that there are multiple outputs adding into the same recepient, we dealt with this by deleting the output from the list which has the same address. I guess we cannot send the same amount transactions to the same recipient, but I am sure we will be able to tackle that as well.
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Later part of the day we have implemented mining rewards feature which I have basically set the reward to zero for cryptocurrency mining method. This reward will be given to the miner on successful mining of the block in the chain. Mining rewards is essential so that the miner is motivated to spend computational power to mine blocks. Though this project will not require much computational power since I have adjusted the mining rate to 4 seconds, hence the average rate of the mining will take about 4 seconds. This will ensure not much computational power is utilised to mine the block.
This will also be updated on a later basis
This project wouldn't have been possible without the help of certain people who although unknowingly helped me to understand concepts of Blockchain and Cryptocurrency systems. The course link which I took is given below.