ICON Developer Portal

ICON Developer Portal

ICON Network is a decentralized smart contract protocol based on ‘loopchain’, a high-performance blockchain engine. The ICON Network aims to remove barriers among different blockchains and allow them to exchange values without intermediaries. By realizing this goal, ICON will realize the mass adoption of blockchain technology and Hyperconnect the World.

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Deploying your SCORE


This document illustrates the steps of SCORE deployment to the local T-Bears server.
To learn more about deploying a SCORE to the Mainnet along with the audit process, please read the Deployment Process


We assume that you already have installed T-Bears. If you have not yet installed it, please read SCORE Quickstart or T-Bears Installation first.

Deploying SCOREs


Before deploying a SCORE, the required files should be packaged into a zip file. In the zip file, SCORE metadata should be included as well as the smart contract source code itself.
The metadata file, package.json, contains a version, main module name, and main class.

Here is an example of package.json file.

    "version": "0.0.1",
    "main_module": "hello_world",
    "main_score": "HelloWorld"

The SCORE execution runtime will find main_score class in the main_module.py to load and execute it on the ICON network.

If you want to make main_module point to a submodule, you can specify the module name as below.

    "version": "0.0.1",
    "main_module": "sub_module.hello_world",
    "main_score": "HelloWorld"

Deploying SCOREs with T-Bears

Here is an example of deploying a SCORE onto the local T-Bears emulator.
If you want to deploy on Mainnet or Testnet, you need to edit uri, nid, and keyStore fields in tbears_cli_config.json.

The SampleToken contract is used in this example.

Deploy SampleToken on Local T-Bears Emulator

  1. Generate T-Bears configuration files if not yet generated.

    $ tbears genconf
  2. Start T-Bears Server (node emulator) on the local environment.

    $ tbears start
  3. Open tbears_cli_config.json and edit it as follows.
    Parameters for on_install() method (_initialSupply and _decimals) should be set under scoreParams field.
    Note that every value in the json file must be a string type as defined in the ICON JSON-RPC v3 Specification, and integer value must be represented as a lowercase HEX string.

        "uri": "",
        "nid": "0x3",
        "keyStore": null,
        "from": "hxe7af5fcfd8dfc67530a01a0e403882687528dfcb",
        "to": "cx0000000000000000000000000000000000000000",
        "deploy": {
            "stepLimit": "0x10000000",
            "mode": "install",
            "scoreParams": {
                "_initialSupply": "0x3e8",
                "_decimals": "0x12"
        "txresult": {},
        "transfer": {
            "stepLimit": "0xf4240"
  4. Deploy the SampleToken
    Using deploy command in T-Bears, you can deploy the sample_token project with configuration tbears_cli_config.json.
    T-Bears makes a zip file from the sample_token directory on the fly and deploys it to the local server.

    $ tbears deploy sample_token -c tbears_cli_config.json
    Send deploy request successfully.
    If you want to check SCORE deployed successfully, execute txresult command
    transaction hash: 0xea834af48150189b4021b9a161d4c0aff3d983ccc47ddc189bac50f55bf580b7
  5. Get transaction result by transaction hash.
    You can check the result of deployment by querying the transaction hash.

    $ tbears txresult 0xea834af48150189b4021b9a161d4c0aff3d983ccc47ddc189bac50f55bf580b7
    Here's the result of the transaction. You can find the `scoreAddress`, which is the address of this deployed SCORE, and that address will be used for invoking external methods of SampleToken later.
    Transaction result: {
        "jsonrpc": "2.0",
        "result": {
            "txHash": "0xea834af48150189b4021b9a161d4c0aff3d983ccc47ddc189bac50f55bf580b7",
            "blockHeight": "0xbe",
            "blockHash": "0xdc85bccb32109da6cfe5bb5308121ce68a1494c499d9dd8c724a0bd7397d0729",
            "txIndex": "0x0",
            "to": "cx0000000000000000000000000000000000000000",
            "scoreAddress": "cx0841205d73b93aec1062877d8d4d5ea54c6665bb",
            "stepUsed": "0x2cc8f10",
            "stepPrice": "0x0",
            "cumulativeStepUsed": "0x2cc8f10",
            "eventLogs": [],
            "logsBloom": "0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000",
            "status": "0x1"
        "id": 1


Updated 14 days ago

Deploying your SCORE

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