Byte Concatenator

Category: Utility · Node Type ID: utility-concat

Concatenates bytes, string, int and bool inputs in input port order (A || B || C ...)

Overview

Concatenates any number of connected input values sequentially into a single contiguous byte array (A || B || C || ...) following the top-to-bottom order of its dynamic input ports.

Each connected input port can be of type Bytes, String, Int, or Bool. Non-byte inputs are automatically converted to bytes using toBytesAuto: Bytes are copied as-is, String is encoded as UTF-8, Int (≥ 0) is encoded as minimal-length big-endian bytes (with 0 encoded as 1 byte 0x00), and Bool is encoded as 1 byte (0x01 for true, 0x00 for false). Unconnected input ports are skipped.

When to Use

Assembling protocol frames or wire messages such as Header || Nonce || Ciphertext || AuthTag.
Combining multiple fields (e.g., SenderID || ReceiverID || Timestamp || Payload) before computing a single Hash Digest, HMAC, or digital signature.

Parameter Configuration

Byte Concatenator has no static algorithm parameters in propertySchema. Its behavior is controlled entirely by the dynamic input ports you add and their top-to-bottom order on the node card.

Port I/O Specification

See Ports & Connections for general wiring rules, data type colors, and dynamic port creation.

Input Ports

Attribute	Specification
Port Nature	Dynamic / Variable Input Ports
Initial Default on Canvas	Starts with 0 input ports (`inputs: []`) when placed on the canvas.
Port Count Range	0 or more input ports (if 0 ports are connected, outputs a 0-byte `Uint8Array`).
Allowed Data Types	`Bytes`, `String`, `Int`, or `Bool` (automatically adopts the upstream port's data type when connected via the `[+]` handle).
Adding & Managing Ports	Drag any upstream output wire onto the `[+]` handle on the left side of the node card to create a new input port, or add/remove/reorder/rename ports in the inspector.
Evaluation & Ordering Rule	Inputs are concatenated strictly in top-to-bottom port order: `Port_1 \|\| Port_2 \|\| ... \|\| Port_N`.

Output Ports

Port Nature: Fixed Output Ports (2 total).

Port Name	Port ID	Data Type	Visibility Condition	Description
`Combined`	`combined`	`Bytes` (A‖B‖...)	Always visible	Single contiguous `Uint8Array` containing the concatenation of all connected input ports in top-to-bottom port order.
`Total Length`	`length`	`Int`	Always visible

Error Cases

When any of the following conditions occurs at runtime, this node transitions to an ERROR state and downstream nodes connected to its outputs do not execute.

Error Code	Default Engine Message	Trigger Condition
`BYTES_INVALID_ARGUMENT`	Invalid argument value	Raised when an argument (such as bit shift count, byte length, or negative integer) is invalid or negative.
`BYTES_INT_OVERFLOW`	The integer cannot be represented with the given length and sign	Raised when the integer value cannot fit within the specified fixed or port byte length.
`BYTES_SIZE_LIMIT`	Result length exceeds the limit	Raised when the resulting byte buffer would exceed the engine's maximum allocation limit.

Examples

Packing Nonce + Ciphertext + Auth Tag into a Single Wire Payload

Combine the 12-byte Nonce, Ciphertext, and 16-byte GCM Auth Tag in order.

Drag the Nonce wire onto the [+] input handle of Byte Concatenator (creating Port 1).
Drag the Ciphertext wire onto [+] (creating Port 2) and the Auth Tag wire onto [+] (creating Port 3).
The Combined output port emits Nonce || Ciphertext || Tag.