中文

dbChain js-client

---

dbChain js-client is the JavaScript implementation of the client side library of dbChain, the blockchain database. With the js-client, developers can quickly start a dbChain application in minutes.

The js-client provides JavaScript functions for

• Generating mnemonic and private/public key pairs
• Checking whether key exists
• Accessing passphrase
• Retrieving list of tables of a database
• Retrieving the options of a talbe
• Retrieving columns of a table
• Retrieving options of a column
• Inserting a row into a table
• Retrieving all rows of a table
• Searching for rows contain certain field value

Install

yarn add dbchain-js-client

or

npm install --save dbchain-js-client

Usage

Generating mnemonic and private/public key pais

import { newMnemonic, createAndStoreKey } from "dbchain-js-client";

const mnemonic = newMnemonic();
// brown deliver ignore estate adjust pond final inject wear return sword silent
const passphrase = "123345678"
createAndStoreKey(mnemonic, passphrase)

Checking whether key exists

import { hasKey } from 'dbchain-js-client;
if(!hasKey()) {
  console.log("User needs to generate and save key pairs")
}

Accessing passphrase

import { hasPassphrase, savePassphrase } from 'dbchain-js-client;

if(!hasPassphrase()) {
  console.log("User needs to input passphrase");
}

// when user login with a passphrase, we usually save it to browser session storage
var passphrase = "12345678"
if (savePassphrase(passphrase)) {
  console.log("passphrase saved successfully");
} else {
  console.log("passphrase is invalid");
}

Retrieving list of tables of a database

import { getTables } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tables = await getTables(appCode);
/*
[
  "supplier",
  "product",
  "customer"
]
*/

Retrieving the options of a table

import { getTableOptions } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";
const options = await getTableOptions(appCode, tableName);
/*
[
  "public"
]
*/

Retrieving columns of a table

import { getTable } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";
const options = await getTable(appCode, tableName);
/*
[
  "name",
  "phone",
  "address_id"
]
*/

Retrieving options of a column

import { getFieldOptions } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";
const fieldName = "phone";
const options = await getFieldOptions(appCode, tableName, fieldName);
/*
[
  "not-null"
]
*/

Inserting a row into a table

import { insertRow } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";

var record = {};
record.name = "Super supplier"
record.phone = "18888888888";
record.address_id = "5";

const options = await insertRow(appCode, tableName, record, function() {
  console.log("inserting record succeeded");
});

Retrieving id of all rows in a table

import { getAllIds } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";
const ids = await getAllIds(appCode, tableName);
/*
[
  "1",
  "2",
  "3",
  "4"
]
*/

Retrieving a row from a table

import { getRow } from "dbchain-js-client";

const appCode = "DJ1PGEQ45A";
const tableName = "supplier";
const record = await getRow(appCode, tableName, "1");
/*
{
  name: "Super supplier",
  phone: "18888888888",
  address_id: "5"
}
*/

License

dbChain js-client is licensed under the Apache-2.0 License.