Get the binary data buffer

The binary data buffer contains all the binary file data processed by a workflow. You need to access it if you want to perform operations on the binary data, such as:

• Manipulating the data: for example, adding column headers to a CSV file.
• Using the data in calculations: for example, calculating a hash value based on it.
• Complex HTTP requests: for example, combining file upload with sending other data formats.

You can access the buffer using n8n's getBinaryDataBuffer() function:

/* 
* itemIndex: number. The index of the item in the input data.
* binaryPropertyName: string. The name of the binary property. 
* The default in the Read/Write File From Disk node is 'data'. 
*/
let binaryDataBufferItem = await this.helpers.getBinaryDataBuffer(itemIndex, binaryPropertyName);

For example:

let binaryDataBufferItem = await this.helpers.getBinaryDataBuffer(0, 'data');
// Returns the data in the binary buffer for the first input item

You should always use the getBinaryDataBuffer() function, and avoid using older methods of directly accessing the buffer, such as targeting it with expressions like items[0].binary.data.data.