# Example
This part will help you understand the fundamental steps to integrate NexaID Network-JS-SDK and complete a basic data verification process through your application.
### Prerequisites
Before you begin, ensure you have the following:
* A valid Template ID (obtainable from the [NexaID Developer Hub](https://testnet-nexaid.hashkeychain.net/))
* The SDK installed (see the [Installation Guide](/nexaid/build-on-nexaid/dapp-integration/installation.md) for instructions)
### Key Features
#### **1. SDK Initialization**
Connect to specified blockchain networks.
Function Name: `init`
**Parameter Description:**
| Parameter Name | Type | Required | Description |
| -------------- | ---------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `provider` | `Provider` | Yes | Web3 provider, can be:
- An instance of ethers.providers.JsonRpcProvider
- An instance of ethers.providers.Web3Provider
- An instance of ethers.providers.JsonRpcSigner
|
| `chainId` | `number` | Yes | The blockchain network ID to connect to. Must be one of [the supported chain IDs](#6-list-of-supported-chains) |
#### **2. Task Submission**
Submit tasks to require an attestation from the network.
Function Name: `submitTask`
**Parameter Description:**
| Parameter Name | Type | Required | Description |
| -------------- | -------- | -------- | ------------ |
| `templateId` | `string` | Yes | Template ID |
| `address` | `string` | Yes | User address |
#### **3. Attestation Execution**
Execute the zkTLS protocol with the network attestor node, and return an attestation issued by the attestor node.
Function Name: `attest`
**Parameter Description:**
| Parameter Name | Type | Required | Description |
| ---------------- | ---------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `templateId` | `string` | Yes | Template ID |
| `address` | `string` | Yes | User address |
| `taskId` | `string` | Yes | Task ID |
| `taskTxHash` | `string` | Yes | Task transaction hash |
| `taskAttestors` | `string[]` | Yes | Array of attestor IDs |
| `additionParams` | `string` | No | Extended parameters in JSON format. Developers can include custom business parameters (e.g., user IDs, session info),These parameters will be returned with the final results `const additionParams = JSON.stringify({ YOUR_CUSTOM_KEY: "YOUR_CUSTOM_VALUE" })` |
| `attMode` | `string` | No | proxytls or mpctls,default is proxytls. You can refer to Overview
section for more details.
|
| `attConditions` | `Array` | No | By default, the zkTLS SDK returns plaintext verification results. You can also define verification logics for hashed results or condition-based results. Example hashed result: `const attConditions = [[{ field: "YOUR_CUSTOM_DATA_FIELD", op: "SHA256" }]]`. Example condition result: `const attConditions = [[{ field: "YOUR_CUSTOM_DATA_FIELD", op: ">", value: "YOUR_CUSTOM_TARGET_DATA_VALUE" }]]`. For the full explanation, see [zkTLS Operations](/nexaid/build-on-nexaid/zktls-operations.md). |
#### **4. Verify & Poll Task Result**
Verify and poll task results. The function is additionally provided for any use case that requires checking the validity of a created attestation through NexaID contracts.
Function Name: `verifyAndPollTaskResult`
**Parameter Description:**
| Parameter Name | Type | Required | Description |
| -------------- | -------- | -------- | ----------------------------------------------------------- |
| `taskId` | `string` | Yes | The ID of the task to poll |
| `reportTxHash` | `string` | No | Report transaction hash (optional) |
| `intervalMs` | `number` | No | Polling interval in milliseconds, default is 2000 |
| `timeoutMs` | `number` | No | Total timeout duration in milliseconds, default is 1 minute |
#### **5. Balance Withdrawal**
Retrieve the fees for unsettled tasks.
Function Name: `withdrawBalance`
**Parameter Description:**
| Parameter Name | Type | Required | Description |
| -------------- | ------------- | -------- | --------------------------------------- |
| `tokenSymbol` | `TokenSymbol` | No | Token type to withdraw, default is ETH |
| `limit` | `number` | No | Withdrawal amount limit, default is 100 |
#### **6. List of Supported Chains**
Property Name：`supportedChainIds`
Currently supports **HashKey Chain Testnet**, additional chains will be added in upcoming releases.
### Using Attestations in zkVM
To retrieve a proof validated using hashed verification logic, you may use **getAllJsonResponse** to collect the associated HTTP response payloads. These two components — the attestation (***hashed data***) and the HTTP responses (***raw data***) — can then be jointly submitted to the zkVM for further computation and verification. For more details about hashed and condition-based logic, see [zkTLS Operations](/nexaid/build-on-nexaid/zktls-operations.md).
```javascript
const attestParams = {
...submitTaskParams,
...submitTaskResult,
attConditions: [
[
{
field: "YOUR_FIELD_NAME",
op: "SHA256",
},
],
],
allJsonResponseFlag: "true", // optional, default is "false"
};
const attestResult = await nexaIDNetwork.attest(attestParams);
const allJsonResponse = await nexaIDNetwork.getAllJsonResponse(
attestResult[0].taskId
);
```
## Complete Example
```javascript
import { NexaIDNetwork } from "@nexaid/network-js-sdk";
async function main() {
const provider = window.ethereum;
const nexaIDNetwork = new NexaIDNetwork();
console.log(nexaIDNetwork.supportedChainIds); // [133]
try {
// 1. Initialize
await nexaIDNetwork.init(provider, 133); // HashKey Chain Testnet
console.log("SDK initialized");
// 2. Submit task, set TemplateID and user address
const submitTaskParams = {
templateId: "YOUR_TEMPLATEID",
address: "YOUR_USER_ADDRESS",
};
const submitTaskResult = await nexaIDNetwork.submitTask(submitTaskParams);
console.log("Task submitted:", submitTaskResult);
// 3. Perform attestation
const attestParams = {
...submitTaskParams,
...submitTaskResult,
// extendedParams: JSON.stringify({ attUrlOptimization: true }),
// Optional: optimize the URL of attestation.
};
const attestResult = await nexaIDNetwork.attest(attestParams);
console.log("Attestation completed:", attestResult);
// 4. Verify and poll task result
const verifyAndPollTaskResultParams = {
taskId: attestResult[0].taskId,
reportTxHash: attestResult[0].reportTxHash,
};
const taskResult = await nexaIDNetwork.verifyAndPollTaskResult(
verifyAndPollTaskResultParams
);
console.log("Final result:", taskResult);
// Optional withdrawal
// const settledTaskIds = await nexaIDNetwork.withdrawBalance();
// console.log("Withdrawn:", settledTaskIds);
} catch (error) {
console.error("Main flow error:", error);
}
}
main();
```
### Understanding the Attestation Structure
When a successful data verification process is completed, you will receive an zkTLS attestation (proof) from the attestor.
For more information about the attestation structure, see the [section](/nexaid/build-on-nexaid/misc/attestation-structure.md) .
### Error Codes
We have defined several error codes in the SDK. If an error occurs during the data verification process, you can refer to the [error code list](/nexaid/build-on-nexaid/misc/error-code.md) for troubleshooting.
---
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