Examples of using the RevPop Blockchain are designed as Nodejs console applications.

There is a docker-compose.yml file with a pre-configured environment.

Requirements:

• Docker
• On Linux, you should also have Docker-compose

To run all samples using Docker, issue a command:

docker-compose run --rm samples node index.js

This environment uses the pre-built Revolution Populi Core Blockchain docker image from revpop-core and Revolution Populi Blockchain library from revpop-js. If you would like to build these dependencies yourself, please refer to the respective links.

To clean up the environment after use, run this command:

docker-compose down

Create a file named docker-compose.override.yml where you can specify any adjustments you need, for example:

version: "3"
services:
  blockchain:
    image: public.ecr.aws/revpop/revpop-core:latest
    ports:
    - 8090:8090
  samples:
    volumes:
    - ./:/app
    - /app/node_modules
    - /app/demo/node_modules

Requirements:

• NodeJS 10+
• MongoDB 3+
• RevPop Blockchain https://gallery.ecr.aws/revpop/revpop-core

Follow the steps in order to run samples on your machine.

1. cp .env.example .env
2. Change variables in .env:
   1. BLOCKCHAIN_URL should point to WS interface of the RevPop Blockchain node
   2. CLOUD_URL is a connection string for the MongoDB driver
3. npm install or yarn
4. Use this genesis file to start blockchain.

This repository was tested in the following environment:

• Ubuntu 18.04 Linux
• NodeJS 12
• MongoDB 3
• RevPop Blockchain latest release from https://gallery.ecr.aws/revpop/revpop-core

To run a separate sample, run a command node sample-name.js. For example:

node sample-1-account.js

To run all samples at once, run a command

node index.js

All sample files will run one by one, the final results should look like this:

===========================
sample_1_account       OK
sample_2_personal_data OK
sample_3_content       OK
sample_4_votes         OK
===========================

• sample-1-account.js
  • Generate private/public keypair according to RevPop Blockchain wallet scheme
  • Get/claim balance object
  • Upgrade the application account to be able to create user accounts
  • Create user account
• sample-2-personal-data.js
  • Save PD photo to cloud storage
  • Create full PD and sign with root hash
  • Save full PD to cloud storage
  • Save full PD record to blockchain
  • Load full PD + record + photo from blockchain and cloud storage
  • Verify full PD with root hash
  • Create partial PD and sign with root hash
  • Save partial PD to cloud storage
  • Save partial PD record to blockchain
  • Load partial PD + record + photo from blockchain and cloud storage
  • Verify partial PD with root hash
• sample-3-content.js
  • Save encrypted content to cloud storage
  • Remove content card
  • Create content card
  • Remove permission
  • Create permission
  • Read permission
  • Read content card
  • Load encrypted content from cloud storage
  • Update + read content card
• sample-4-votes.js
  • Create content cards
  • Find witness to choose master node (in three different ways)
  • Vote for content ("liking")
  • Read and check vote counters of content
  • Share voting information with another account (friend)
  • Read votes of another account (friend)

{
    subject_account: subject_acc.id,
    operator_account: subject_acc.id,
    url: "https://host/path?a=1&b=2",
    hash: "94b07b038cd395c13938474e7c81b050949577103f8cd12e4a294e4b2fa47d95"
}

Fields:

• subject_account - account id of subject of the personal data,
• operator_account - account id of operator of the personal data,
• url - URL of cloud storage record of the personal data,
• hash - hex lowercase sha256 hash of all parts of the personal data according to scheme: sha256(sha256(part1_salt + ':' + part1_json) + ... + sha256(partN_salt + ':' + partN_json)). Parts must be sorted by its path. JSON of all parts must have all keys sorted and must be one-line (i.e. no indents, no whitespaces).

Record stored by subject for their own access has rules:

• subject_account and operator_account must be equal,
• tuple (subject_account, operator_account, hash) must be unique.

Record stored by subject for operator access:

• subject_account and operator_account must be not equal,
• tuple (subject_account, operator_account) must be unique.

Field url of blockchain record refers to ciphertext form of record in cloud storage. Ciphertext form can be decrypted to plaintext form using subject public key and operator private key and nonce. Plaintext form can be encrypted to ciphertext form using subject private key and operator public key and nonce.

{
    data: "MlETwxAtxUDynEqvHMZtcPU5v9pLl66mwT1EnkoXgik=:zwCAzJCRf1bSI............00oFx7Z71JiMEQ="
}

Fields:

• data - two parts joined with ':' separator, (1) base64 of random 32-byte nonce used in encryption of plaintext form, and (2) base64 of JSON-stringified (in single line) and encrypted plaintext form of the personal data,

{
    content: {
        name: {
            first: "James",
            last: "Bond"
        },
        email: "bond@mi5.gov.uk"
    },
    parts: [
        {
            path: "name",
            salt: "Jg+8wcqQWL0="
        },
        {
            path: "email",
            salt: "H1ZBI/2ggGw="
        }
    ],
    missed_parts: [
        {
            path: "phone",
            hash: "05bf87c8d4425c58f7d63508535e3a98d02af4a33a0ef7f463c2ccbbf4d7633a"
        },
    ]
}

Fields:

• content - content of the personal data (json),
• parts - list of parts info of the personal data,
• parts[].path - dot-separated path of the part in content,
• parts[].salt - salt of the part used in its hashing (base64 of 64-bit random number),
• missed_parts - list of missed parts info of the personal data,
• missed_parts[].path - dot-separated path of the missed part in content,
• missed_parts[].hash - hash of the missed part and its salt (hex),

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

GPLv3