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besu/docs/Using-Pantheon/Transactions/Transactions.md

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description: Some use cases of creating transactions on a Pantheon network
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# Creating and Sending Transactions
You can send signed transactions using the [`eth_sendRawTransaction`](../../Reference/Pantheon-API-Methods.md#eth_sendrawtransaction) JSON-RPC API method.
Signed transactions can be simple value transfers, contract creation, or contract invocation.
Example scripts are provided to create a signed raw transaction that can be passed to
[`eth_sendRawTransaction`](../../Reference/Pantheon-API-Methods.md#eth_sendrawtransaction) to send Ether
and create a smart contract.
!!! warning "Private keys"
Do not use the accounts in the examples on mainnet or any public network except for testing.
The private keys are displayed which means the accounts are not secure.
All accounts and private keys in the examples are from the `dev.json` genesis file in the
[`/pantheon/ethereum/core/src/main/resources`](https://github.com/PegaSysEng/pantheon/tree/master/config/src/main/resources) directory.
In production environments avoid exposing your private keys by creating signed transactions
offline, or use [EthSigner](https://docs.ethsigner.pegasys.tech/) to isolate your private keys and
sign transactions with [`eth_sendTransaction`](https://docs.ethsigner.pegasys.tech/Using-EthSigner/Using-EthSigner/#eth_sendtransaction).
!!! tip
Libraries such as [web3j](https://github.com/web3j/web3j) or [ethereumj](https://github.com/ethereum/ethereumj)
and tools such as [MyCrypto](https://mycrypto.com/) can also be used to create signed transactions.
You can use the example Javascript scripts to create and send raw transactions in the private network
created by the [Private Network Quickstart](../../Tutorials/Private-Network-Quickstart.md).
Update the `JSON-RPC endpoint` in the following examples to the endpoint for the private
network displayed after running the `./run.sh` script.
## Example Javascript scripts
### 1. Requirements
- [Node.js (version > 10)](https://nodejs.org/en/download/)
- [web3.js 1.0.0 beta](https://github.com/ethereum/web3.js/) and [ethereumjs 1.3](https://github.com/ethereumjs/ethereumjs-tx).
These dependencies are defined in the included [`package.json`](scripts/package.json) file.
### 2. Create Directory
```bash
mkdir example_scripts
```
### 3. Copy Files
Copy the following files to the `example_scripts` directory:
- [`package.json`](scripts/package.json)
- [`create_value_raw_transaction.js`](scripts/create_value_raw_transaction.js)
- [`create_contract_raw_transaction.js`](scripts/create_contract_raw_transaction.js)
### 4. Retrieve Dependencies
```bash
cd example_scripts
npm install
```
### 5. Send Ether
The following is the example JavaScript script that displays a signed raw transaction string to send Ether.
!!! example "Send Ether example : create_value_raw_transaction.js"
```javascript linenums="1"
{! Using-Pantheon/Transactions/scripts/create_value_raw_transaction.js !}
```
Run the `create_value_raw_transaction.js` script:
```bash tab="Command"
node create_value_raw_transaction.js <YOUR JSON-RPC HTTP ENDPOINT>
```
```bash tab="Example"
node create_value_raw_transaction.js http://localhost:32770/jsonrpc
```
!!! tip
The default JSON-RPC HTTP endpoint for `create_value_raw_transaction.js` is `http://localhost:8545`.
If using `http://localhost:8545`, run `node create_value_raw_transaction.js`.
A signed raw transaction string is displayed.
You can send the raw transaction yourself or let the script send it using the web3.js library.
If sending it yourself, the cURL command is displayed and can be copied and pasted. Otherwise, the script sends it and
the transaction receipt is displayed.
### 6. Create A Smart Contract
The following is the example JavaScript script that displays a signed raw transaction string to create a contract.
!!! example "Create a contract example : create_contract_raw_transaction.js"
```javascript linenums="1"
{! Using-Pantheon/Transactions/scripts/create_contract_raw_transaction.js !}
```
Run the `create_contract_raw_transaction.js` script:
```bash tab="Command"
node create_contract_raw_transaction.js <YOUR JSON-RPC HTTP ENDPOINT>
```
```bash tab="Example"
node create_contract_raw_transaction.js http://localhost:32770/jsonrpc
```
!!! tip
The default JSON-RPC HTTP endpoint for `create_contract_raw_transaction.js` is `http://localhost:8545`.
If using `http://localhost:8545`, run `node create_contract_raw_transaction.js`.
A signed raw transaction string is displayed.
You can send the raw transaction yourself or let the script send it using the web3.js library.
If sending it yourself, the cURL command is displayed and can be copied and pasted. Otherwise, the script sends it and
the transaction receipt is displayed.
## eth_call vs eth_sendRawTransaction
You can interact with contracts using [eth_call](../../Reference/Pantheon-API-Methods.md#eth_call)
or [eth_sendRawTransaction](../../Reference/Pantheon-API-Methods.md#eth_sendrawtransaction).
The table below compares the characteristics of both calls.
| eth_call | eth_sendRawTransaction |
|---------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------|
| Read-only | Write |
| Invokes contract function locally | Broadcasts to network |
| Does not change state of blockchain | Updates blockchain (for example, transfers ether between accounts) |
| Does not consume gas | Requires gas |
| Synchronous | Asynchronous |
| Return value of contract function available immediately | Returns transaction hash only. Possible transaction may not be included in a block (for example, if the gas price is too low). |