HODLTogether NFT Distribution

How to setup chainlink node

Setting up the .env file

• mkdir ~/.chainlink-kovan

• touch .env

• Put this inside your ~/.chainlink-kovan/.env file:

    ROOT=/chainlink
    LOG_LEVEL=debug
    ETH_CHAIN_ID=42
    MIN_OUTGOING_CONFIRMATIONS=2
    LINK_CONTRACT_ADDRESS=0xa36085F69e2889c224210F603D836748e7dC0088
    CHAINLINK_TLS_PORT=0
    SECURE_COOKIES=false
    GAS_UPDATER_ENABLED=true
    ALLOW_ORIGINS=*
    ETH_URL=CHANGEME

Set the local postgres DATABASE_URL Config

• sudo -i -u postgres
• psql
• ALTER USER postgres PASSWORD '12345678'
• Postges setup:

    username: postgres
    password: postgres
    server: localhost
    port: 5432
    database: postgres

• Add these to your ~/.chainlink-kovan/.env file:

    DATABASE_URL=postgresql://postgres:postgres@localhost:5432/postgres
    DATABASE_TIMEOUT=0

Helpful resources

• https://docs.chain.link/docs/running-a-chainlink-node
• https://docs.chain.link/docs/fulfilling-requests
• https://docs.chain.link/docs/job-specifications#config

How to start chainlink node?

• cd ~/.chainlink-kovan
• docker run --name chainlink-kovan --network host -p 6688:6688 -v ~/.chainlink-kovan:/chainlink -it --env-file=.env smartcontract/chainlink:0.10.3 local n
• Visit in browser: localhost:6688 and sign in with your credentials
• docker network ls: make sure host is there.

Stopping & deleting container:

• docker stop chainlink-kovan && docker container rm chainlink-kovan

Screenshots

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How to deploy APIConsumer

• Assuming that you have successfully setup the chainlink node.

• truffle compile

• truffle migrate --reset --network kovan/truffle migrate --f 3 --network kovan(If you update APIConsumer only.)

• yarn verify

• truffle exec scripts/1_fund_link.js --network kovan

• Needs to be done for the first time:

  • truffle exec scripts/2_add_permission.js --network kovan
  • Add a new job from the NODE UI, with job spec from: job_specs/eth=>bool.json & don't forget to copy Oracle address into job_spec

• truffle exec scripts/3_request.js --network kovan

• You can see a job assingned in the node operator browser window:

  • as it will succeed, check the transaction hash for any errors

• truffle exec scripts/4_read_val.js --network kovan

• node help/postgres.check.js: Check postgres connection & NODE funds

How to run local express server

• yarn server: Start in dev mode
• yarn start: Start in prod mode
• Open a query like: [http://localhost:5000/check/nft/0xcfdf8fffaa4dd7d777d448cf93dd01a45e97d782/LINK]

ENV variables for the project

A template of .env file is already given as .env.example, set them accordingly:

LINK_CONTRACT_ADDRESS="..."
RPC_URL="..."
MNEMONIC="..."
NODE_ADDRESS="..."
JOB_ID="..."
ETHERSCAN_API_KEY="..."

Directory structure

pam@g3:~/cl-node$ tree -I 'node_modules|build'
.
├── contracts
│   ├── Distributor
│   │   ├── APIConsumer.sol
│   │   └── TokenHandler.sol
│   ├── ERC1155
│   │   └── Token.sol
│   └── Migrations.sol
├── help
│   ├── node.info.js
│   ├── postgres.check.js
│   └── query.js
├── index.js
├── job_specs
│   └── eth=>bool.json
├── migrations
│   ├── 1_initial_migration.js
│   ├── 2_oracle.js
│   ├── 3_token.js
│   └── 4_testnet_consumer.js
├── package.json
├── README.md
├── scripts
│   ├── 1_fund_link.js
│   ├── 2_add_permission.js
│   ├── 3_request.js
│   └── 4_read_val.js
├── truffle-config.js
└── yarn.lock

7 directories, 21 files

Deployments

• Verifying Oracle
• Verifying APIConsumer
• Verifying Token
• Node address: 0xBcabE53a3cd718bc48137831f6F788C8AB35D10a
• JobId: 0f79687897bc48b8928bd133a52042e2