# Configurations Developers can develop wallet application using our web sdk. Install the `dcent-web-connector` from npm repository. ```shell npm install dcent-web-connector ``` Developer can access api through `window.DcentWebConnector` object or `DcentWebConnector` object. ```javascript const DcentWebConnector = require('dcent-web-connector') ``` ### Requirement * Must have a `D'CENT Biometric wallet`.\ You can get it at D'CENT website : * You need to install the lastest `D'CENT Bridge`.\ D'CENT Bridge Download : * D'CENT Biometric will be connected with your PC or Labtop using USB Cable(Micro USB 5-pin type). ## Basic structure ### Functions All API functions return a `Promise`.\ When function processing is completed, it is resolved. If an error occurs, it is rejected.\ In either case, respond with a JSON object. ### Returned JSON object type ```json { "header": { "version": "1.0", "request_from": "", "status": "" }, "body": { "command" : "", "parameter" : {} } } ``` ### Common Errors If D'CENT wallet isn't connected via USB, you'll get the following error: ```json { "header": { "version": "1.0", "request_from": "ethereum", "status": "error" }, "body": { "command": "transaction", "error": { "code": "user_cancel", "message": "user cancel" } } } ``` When executing a function that requires user authentication, an error occurs if the user cancels the authentication. The following shows the user cancel error in the Ethereum signed Transaction. ```json { "header": { "version": "1.0", "request_from": "dcent-web", "status": "error" }, "body": { "error": { "code": "pop-up_closed", "message": "Pop-up windows has been closed" } } } ``` If the bridge service popup window is closed while calling a function and waiting, the following error occurs: ```json { "header": { "version": "1.0", "request_from": "wam", "status": "error" }, "body": { "error": { "code": "no_device", "message": "D'CENT Biometric Wallet is not connected" } } } ``` ## Basic functions ### `DcentWebConnector` initialize `dcent-web-connector` provides functions for using D'CENT Biometric Wallet. ```javascript var result try{ result = await DcentWebConnector.info() }catch(e){ result = e } ``` `info()` returns : ```json { "header": { "version": "1.0", "request_from": "", "status": "" }, "body": { "command" : "", "parameter" : { "version": "1.0.0", "isUsbAttached": "true | false" } } } ``` When the function is called from your web application, if D'CENT Bridge Service is not running as a pop-up, `dcent-web-connector` will automatically open a pop-up window and send a function request ### Set TimeOut Time ```json { "header": { "version": "1.0", "response_from": "dcent-web", "status": "error" }, "body": { "error": { "code": "time_out", "message": "The function execution time has expired" } } } ``` All functions except setTimeOutMs function are called and then respond with `JSON Object` as below when timeout occurs. ```javascript try { await dcent.setTimeOutMs(60000) // 60 sec, The default value is 60 seconds. } catch (e) { console.log(e) } ``` You can set the timeout time by calling `setTimeOutMs ()` as shown below. Sets the maximum time the function will run. Once set the timeout Time, it is valid until the value is set again. The default value is 60 seconds. ### Close pop-up window `dcent-web-connector` will automatically open a pop-up window and send a function request. After each request to device is ended, it is recommended to close popup for enhancing user experience. ```javascript var result try{ result = await DcentWebConnector.info() }catch(e){ result = e } // close pop-up window of D'CENT Bridge Service DcentWebConnector.popupWindowClose() ``` ### Set Device Connection Listener Set listener for device connection state. Before processing a functions request, `dcent-web-connector` check the device connection state. If the state is changed, the device connection listener will be called. ```javascript // device connection listener ( callback ) function connectionListener(state) { if (state === DcentWebConnector.state.CONNECTED) { console.log('DCENT is Connected'); } else if (state === DcentWebConnector.state.DISCONNECTED) { console.log('DCENT is Disconnected'); } } try { // set the device connection listener DcentWebConnector.setConnectionListener(connectionListener) } catch(e) { } ``` ### Address Path All address path in the API should follow BIP44 rules. ``` m / purpose' / coin_type' / account' / change / address_index ``` ### Coin Type `DcentWebConnector.coinType` is defined in the source code below. * ## APIs ### Wallet device and accounts info. {% content-ref url="device-and-accounts-info." %} [device-and-accounts-info.](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/device-and-accounts-info.) {% endcontent-ref %} ### Address & XPUB You can get an address or XPUB for a specific private key with the APIs below. {% content-ref url="address-and-xpub" %} [address-and-xpub](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/address-and-xpub) {% endcontent-ref %} ### Ethereum & EVM compatible network You can find the APIs to generate signature for Ethereum, EVM compatible network. {% content-ref url="ethereum-and-evm-compatible" %} [ethereum-and-evm-compatible](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/ethereum-and-evm-compatible) {% endcontent-ref %} ### Klaytn You can find the APIs to generate signature for Klaytn network. {% content-ref url="klaytn" %} [klaytn](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/klaytn) {% endcontent-ref %} ### Bitcoin & Bitcoin compatible network You can find the APIs to generate signature for Bitcoin and Bitcoin compatible network. {% content-ref url="bitcoin" %} [bitcoin](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/bitcoin) {% endcontent-ref %} ### XRPL (XRP Ledger) You can find the APIs to generate signature for XRPL transactions. {% content-ref url="xrpl-xrp-ledger" %} [xrpl-xrp-ledger](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/xrpl-xrp-ledger) {% endcontent-ref %} ### Hedera (HBAR & HTS) You can find the APIs to generate signature for Hedera transactions. {% content-ref url="hedera-hbar-and-hts" %} [hedera-hbar-and-hts](https://dev-docs.dcentwallet.com/dcent-biometric-wallet-for-pc/dcent-web-connector/hedera-hbar-and-hts) {% endcontent-ref %}