# meterify.module.options

A module provides several options for configuring the transaction confirmation workflow or for defining default values. This document describes the available option properties on a module.

**Example:**

```javascript
import Web3 from 'web3';

    const meterify = require("meterify").meterify;

    const options = {
        defaultAccount: '0x0',
        defaultBlock: 'latest',
        defaultGas: 1,
        defaultGasPrice: 0,
        transactionBlockTimeout: 50,
        transactionConfirmationBlocks: 24,
        transactionPollingTimeout: 480,
        transactionSigner: new CustomTransactionSigner()
    }

    const web3 = new Web3('https://testnet.meter.io', null, options);

    const meterify = meterify(web3, "https://testnet.meter.io");
```

## defaultBlock <a href="#defaultblock" id="defaultblock"></a>

```javascript
    web3.defaultBlock
    web3.eth.defaultBlock
    web3.shh.defaultBlock
    ...
```

```javascript
    web3.eth.getBalance();
    web3.eth.getCode();
    web3.eth.getTransactionCount();
    web3.eth.getStorageAt();
    web3.eth.call();
    new web3.eth.Contract() -> myContract.methods.myMethod().call();`
```

The default block is used for all methods which have a block parameter. You can override it by passing the block parameter if a block is required.

The `defaultBlock` property can return the following values:

| Value     | Type     | Description                                                |
| --------- | -------- | ---------------------------------------------------------- |
| a number  | `Number` | A block number                                             |
| `genesis` | `String` | The genesis block                                          |
| `latest`  | `String` | The latest block (current head of the blockchain)          |
| `pending` | `String` | The currently mined block (including pending transactions) |

Default is `latest`

## defaultAccount <a href="#defaultaccount" id="defaultaccount"></a>

```javascript
    web3.defaultAccount
    web3.eth.defaultAccount
    web3.shh.defaultAccount
    ...
```

This default address is used as the default `"from"` property, if no `"from"` property is specified.

**Returns:**

| Type                | Description                                                                                                                |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------- |
| `String` - 20 Bytes | Any Ethereum address. You need to have the private key for that address in your node or keystore. (Default is `undefined`) |

## defaultGasPrice <a href="#defaultgasprice" id="defaultgasprice"></a>

```javascript
    web3.defaultGasPrice
    web3.eth.defaultGasPrice
    web3.shh.defaultGasPrice
    ...
```

The default gas price which will be used for a request.

**Returns:**

| Type                 | Description                                        |
| -------------------- | -------------------------------------------------- |
| `string` or `number` | The current value of the defaultGasPrice property. |

## defaultGas <a href="#defaultgas" id="defaultgas"></a>

```javascript
    web3.defaultGas
    web3.eth.defaultGas
    web3.shh.defaultGas
    ...
```

The default gas which will be used for a request.

**Returns:**

| Type                 | Description                                   |
| -------------------- | --------------------------------------------- |
| `string` or `number` | The current value of the defaultGas property. |

## transactionBlockTimeout <a href="#transactionblocktimeout" id="transactionblocktimeout"></a>

```javascript
    web3.transactionBlockTimeout
    web3.eth.transactionBlockTimeout
    web3.shh.transactionBlockTimeout
    ...
```

The `transactionBlockTimeout` will be used over a socket-based connection. This option does define the amount of new blocks it should wait until the first confirmation happens. This means the PromiEvent rejects with a timeout error when the timeout got exceeded.

**Returns:**

| Type     | Description                                  |
| -------- | -------------------------------------------- |
| `number` | The current value of transactionBlockTimeout |

## transactionConfirmationBlocks <a href="#transactionconfirmationblocks" id="transactionconfirmationblocks"></a>

```javascript
    web3.transactionConfirmationBlocks
    web3.eth.transactionConfirmationBlocks
    web3.shh.transactionConfirmationBlocks
    ...
```

This defines the number of blocks it requires until a transaction will be handled as confirmed.

**Returns:**

| Type     | Description                                        |
| -------- | -------------------------------------------------- |
| `number` | The current value of transactionConfirmationBlocks |

## transactionPollingTimeout <a href="#transactionpollingtimeout" id="transactionpollingtimeout"></a>

```javascript
    web3.transactionPollingTimeout
    web3.eth.transactionPollingTimeout
    web3.shh.transactionPollingTimeout
    ...
```

The `transactionPollingTimeout` will be used over a HTTP connection. This option does define the amount of polls (each second) it should wait until the first confirmation happens.

**Returns:**

| Type     | Description                                    |
| -------- | ---------------------------------------------- |
| `number` | The current value of transactionPollingTimeout |

## transactionSigner <a href="#transactionsigner" id="transactionsigner"></a>

```javascript
    web3.eth.transactionSigner
    ...
```

The `TransactionSigner` property does provide us the possibility to customize the signing process of the `Eth` module and the related sub-modules.

The interface of a `TransactionSigner`:

```javascript

    interface TransactionSigner {
        sign(txObject: Transaction): Promise<SignedTransaction>
    }

    interface SignedTransaction {
        messageHash: string,
        v: string,
        r: string,
        s: string,
        rawTransaction: string
    }
```

**Returns:**

| Type                | Description                                   |
| ------------------- | --------------------------------------------- |
| `TransactionSigner` | A JavaScript class of type TransactionSigner. |

## setProvider <a href="#setprovider" id="setprovider"></a>

```javascript

    web3.setProvider(myProvider)
    web3.eth.setProvider(myProvider)
    web3.shh.setProvider(myProvider)
    ...
```

Will change the provider for its module.

**Example:**

```javascript

    import Web3 from 'web3';

    const web3 = new Web3('http://localhost:8545');

    // or
    const web3 = new Web3(new Web3.providers.HttpProvider('http://localhost:8545'));

    // change provider
    web3.setProvider('ws://localhost:8546');
    // or
    web3.setProvider(new Web3.providers.WebsocketProvider('ws://localhost:8546'));

    // Using the IPC provider in node.js
    const net = require('net');
    const web3 = new Web3('/Users/myuser/Library/Ethereum/geth.ipc', net); // mac os path

    // or
    const web3 = new Web3(new Web3.providers.IpcProvider('/Users/myuser/Library/Ethereum/geth.ipc', net)); // mac os path
    // on windows the path is: '\\\\.\\pipe\\geth.ipc'
    // on linux the path is: '/users/myuser/.ethereum/geth.ipc'
```

Note: When called on the umbrella package `web3` it will also set the provider for all sub modules `web3.eth`, `web3.shh`, etc.

**Parameters:**

| Type                 | Description                                                                            |
| -------------------- | -------------------------------------------------------------------------------------- |
| `Object` or `String` | `provider`: a valid provider                                                           |
| `Net`                | `net`: (optional) the node.js Net package. This is only required for the IPC provider. |

**Returns:**

`Boolean`

## providers <a href="#providers" id="providers"></a>

```javascript

    Web3.providers
    Eth.providers
    ...
```

**Example:**

```javascript

    const Web3 = require('web3');
    // use the given Provider, e.g in Mist, or instantiate a new websocket provider
    const web3 = new Web3(Web3.givenProvider || 'ws://localhost:8546');
    // or
    const web3 = new Web3(Web3.givenProvider || new Web3.providers.WebsocketProvider('ws://localhost:8546'));

    // Using the IPC provider in node.js
    const net = require('net');

    const web3 = new Web3('/Users/myuser/Library/Ethereum/geth.ipc', net); // mac os path
    // or
    const web3 = new Web3(new Web3.providers.IpcProvider('/Users/myuser/Library/Ethereum/geth.ipc', net)); // mac os path
    // on windows the path is: '\\\\.\\pipe\\geth.ipc'
    // on linux the path is: '/users/myuser/.ethereum/geth.ipc'
```

Contains the current available providers.

`Object` with the following providers:

| Property | Name                | Description                                                                                      |
| -------- | ------------------- | ------------------------------------------------------------------------------------------------ |
| `Object` | `HttpProvider`      | The HTTP provider is **deprecated**, as it will not work for subscriptions.                      |
| `Object` | `WebsocketProvider` | The Websocket provider is the standard for usage in legacy browsers.                             |
| `Object` | `IpcProvider`       | The IPC provider is used node dapps when running a local node. Gives the most secure connection. |

## givenProvider <a href="#givenprovider" id="givenprovider"></a>

```javascript
    Web3.givenProvider
    web3.eth.givenProvider
    web3.shh.givenProvider
    ...
```

**Example:**

```javascript

    web3.setProvider(Web3.givenProvider || 'ws://localhost:8546');
```

When using web3.js in an Ethereum compatible browser, it will set with the current native provider by that browser. Will return the given provider by the (browser) environment, otherwise `null`.

**Returns:**

| Type     | Description                        |
| -------- | ---------------------------------- |
| `Object` | The given provider set or `false`. |

## currentProvider <a href="#currentprovider" id="currentprovider"></a>

```javascript

    web3.currentProvider
    web3.eth.currentProvider
    web3.shh.currentProvider
    ...
```

Will return the current provider.

**Example:**

```javascript

    if (!web3.currentProvider) {
        web3.setProvider('http://localhost:8545');
    }
```

**Returns:**

| Type     | Description               |
| -------- | ------------------------- |
| `Object` | The current provider set. |

## BatchRequest <a href="#batchrequest" id="batchrequest"></a>

```javascript

    new web3.BatchRequest()
    new web3.eth.BatchRequest()
    new web3.shh.BatchRequest()
    ...
```

**Example:**

```javascript

    const contract = new web3.eth.Contract(abi, address);

    const batch = new web3.BatchRequest();
    batch.add(web3.eth.getBalance.request('0x0000000000000000000000000000000000000000', 'latest'));
    batch.add(contract.methods.balance(address).call.request({from: '0x0000000000000000000000000000000000000000'}));
    batch.execute().then(...);
```

Class to create and execute batch requests.

**Parameters:**

none

**Returns:**

| Type     | Description                     |
| -------- | ------------------------------- |
| `Object` | Contains the following methods: |

| Method         | Description                                |
| -------------- | ------------------------------------------ |
| `add(request)` | To add a request object to the batch call. |
| `execute()`    | Will execute the batch request.            |