# Append to a file

A transaction that appends new file content to the end of an existing file. The contents of the file can be viewed by submitting a FileContentsQuery request.

**Transaction Signing Requirements**

* The key on the file is required to sign the transaction if different than the client operator account key

**Transaction Fees**

* Please see the transaction and query [fees](/docs/networks/mainnet/fees.md#transaction-and-query-fees) table for base transaction fee
* Please use the [Hedera fee estimator](https://hedera.com/fees) to estimate your transaction fee cost

| Constructor               | Description                                  |
| ------------------------- | -------------------------------------------- |
| `FileAppendTransaction()` | Initializes the FileAppendTransaction object |

```java
new FileAppendTransaction()
```

{% hint style="info" %}
The default max transaction fee (1 hbar) is not enough to create a file. Use `setMaxTransactionFee()`to change the default max transaction fee from 1 hbar to 2 hbars. The default chunk size is 2,048 bytes.
{% endhint %}

### Methods

| Method                         | Type      | Description                  | Requirement |
| ------------------------------ | --------- | ---------------------------- | ----------- |
| `setFileId(<fileId>)`          | FileId    | The ID of the file to append | Required    |
| `setContents(<text>)`          | String    | The content in String format | Optional    |
| `setContents(<content>)`       | byte \[ ] | The content in byte format   | Optional    |
| `setChunkSize(<chunkSize>)`    | int       | The chunk size               | Optional    |
| `setMaxChunkSize(<maxChunks>)` | int       | The max chunk size           | Optional    |

{% tabs %}
{% tab title="Java" %}

```java
//Create the transaction
FileAppendTransaction transaction = new FileAppendTransaction()
    .setFileId(newFileId)
    .setContents("The appended contents");

//Change the default max transaction fee to 2 hbars
FileCreateTransaction modifyMaxTransactionFee = transaction.setMaxTransactionFee(new Hbar(2)); 

//Prepare transaction for signing, sign with the key on the file, sign with the client operator key and submit to a Hedera network
TransactionResponse txResponse = modifyMaxTransactionFee.freezeWith(client).sign(key).execute(client);

//Request the receipt
TransactionReceipt receipt = txResponse.getReceipt(client);

//Get the transaction consensus status
Status transactionStatus = receipt.status;

System.out.println("The transaction consensus status is " +transactionStatus);

//v2.0.0
```

{% endtab %}

{% tab title="JavaScript" %}

```javascript
//Create the transaction
const transaction = await new FileAppendTransaction()
    .setFileId(newFileId)
    .setContents("The appended contents")
    .setMaxTransactionFee(new Hbar(2))
    .freezeWith(client);

//Sign with the file private key
const signTx = await transaction.sign(fileKey);

//Sign with the client operator key and submit to a Hedera network
const txResponse = await signTx.execute(client);

//Request the receipt
const receipt = await txResponse.getReceipt(client);

//Get the transaction consensus status
const transactionStatus = receipt.status;

console.log("The transaction consensus status is " +transactionStatus);

//v2.0.5
```

{% endtab %}

{% tab title="Go" %}

```java
//Create the transaction
transaction2 := hedera.NewFileAppendTransaction().
        SetFileID(newFileId).
        SetContents([]byte("The appended contents"))

//Change the default max transaction fee to 2 hbars
modifyMaxTransactionFee := transaction.SetMaxTransactionFee(hedera.HbarFrom(2, hedera.HbarUnits.Hbar))

//Prepare transaction for signing, 
freezeTransaction, err := modifyMaxTransactionFee.FreezeWith(client)
if err != nil {
        panic(err)
}

//Sign with the key on the file, sign with the client operator key and submit to a Hedera network
txResponse2 err := freezeTransaction.Sign(fileKey).Execute(client)
if err != nil {
        panic(err)
}

//Request the receipt
receipt, err := txResponse.GetReceipt(client)
if err != nil {
        panic(err)
}

//Get the transaction consensus status
transactionStatus := receipt.Status

fmt.Println("The transaction consensus status is ", transactionStatus)

//v2.0.0
```

{% endtab %}
{% endtabs %}

## Get transaction values

| Method          | Type   | Description                    | Requirement |
| --------------- | ------ | ------------------------------ | ----------- |
| `getFileId()`   | FileId | The file ID in the transaction | Optional    |
| `getContents()` | String | The content in the transaction | Optional    |

{% tabs %}
{% tab title="Java" %}

```java
//Create the transaction
FileAppendTransaction transaction = new FileAppendTransaction()
    .setFileId(newFileId)
    .setContents("The appended contents");

//Get the contents
ByteString getContents = transaction.getContents();

//v2.0.0
```

{% endtab %}

{% tab title="JavaScript" %}

```java
//Create the transaction
const transaction = new FileAppendTransaction()
    .setFileId(newFileId)
    .setContents("The appended contents");

//Get the contents
const getContents = transaction.getContents();
```

{% endtab %}

{% tab title="Go" %}

```java
//Create the transaction
transaction2 := hedera.NewFileAppendTransaction().
    SetFileID(newFileId).
        SetContents([]byte("The appended contents"))

//Get the contents
getContents2 := transaction2.GetContents()

//v2.0.0
```

{% endtab %}
{% endtabs %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://dev.uniultra.xyz/docs/sdks-and-apis/sdks/file-service/append-to-a-file.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.