---
title: Heroku Logplex
slug: telemetry-pipeline/heroku-logplex
docTags: 
createdAt: 2025-04-21T00:52:09.076Z
---

## Heroku Logplex Source

The Heroku Logplex source receives log data from **Heroku log drains** via Heroku’s Logplex system. Logplex is the routing layer responsible for collecting and forwarding logs generated by Heroku applications, dynos, routers, and add-ons.

This source runs in an **aggregator** role and is designed for reliable log ingestion with **at-least-once delivery guarantees** and acknowledgement support.

## Network Binding

### Required Field

- **address** (string)
   The socket address the source listens on for incoming HTTP connections.
   This must include both IP address and port. 

This address must be reachable from Heroku’s Logplex infrastructure or from any intermediary forwarding layer.

## Acknowledgements

### Deprecated Configuration

- **acknowledgements.enabled** 

Acknowledgement configuration at the source level is deprecated.
 Acknowledgement behavior is now controlled globally or at the sink level.

Changing this setting has **no effect** on delivery guarantees.

## Authentication (auth)

Defines how incoming HTTP requests are authenticated.

:::BlockQuote
Authentication credentials are passed via HTTP headers and must be used **only over HTTPS**.
:::

### Supported Strategies

- **basic**
   Uses HTTP Basic Authentication with a username and password. 
- **custom**
   Uses a **VRL boolean expression** to validate incoming requests. 

### Strategy-Specific Fields

- **auth.username**
   Username for basic authentication. 
- **auth.password**
   Password for basic authentication. 
- **auth.source**
   VRL expression used to validate the incoming request when using custom authentication. 

## Decoding Configuration (decoding)

Controls how incoming raw bytes are converted into log events. Some decoders may also infer event structure automatically.

### Codec Selection

- **decoding.codec** (string, default: bytes) 

Supported codecs include:

- bytes 
- json 
- avro 
- gelf 
- influxdb 
- syslog 
- protobuf 
- otlp 
- native 
- native\_json 
- vrl 

### Codec-Specific Behavior

- **Lossy decoding** options determine whether invalid UTF-8 sequences are replaced or rejected. 
- **Avro and Protobuf** codecs require schema or descriptor configuration. 
- **VRL decoding** executes a VRL program to produce the final event. 

## Framing Configuration (framing)

Defines how individual log events are extracted from the incoming byte stream before decoding.

### Supported Framing Methods

- bytes 
- character\_delimited 
- newline\_delimited 
- length\_delimited 
- varint\_length\_delimited 
- octet\_counting 
- chunked\_gelf 

Each framing method supports safety limits (such as maximum frame length or timeout) to prevent unbounded memory usage when processing malformed input.

## HTTP Keepalive (keepalive)

Controls HTTP connection reuse behavior for incoming log drain connections.

### Available Options

- **max\_connection\_age\_secs**
   Maximum lifetime of an HTTP connection before it is closed. 
- **max\_connection\_age\_jitter\_factor**
   Adds randomized jitter to connection lifetime to avoid connection storms. 

These settings apply to HTTP/0.9, HTTP/1.0, and HTTP/1.1 connections.

## Query Parameters

- **query\_parameters** (list of strings)
   Specifies which URL query parameters are included in emitted log events. 

Wildcards are supported. Query parameters override body fields when name conflicts occur.

## TLS Configuration (tls)

Configures TLS for incoming HTTPS connections.

### Supported Options

- **enabled** 
- **crt\_file** 
- **key\_file** 
- **key\_pass** 
- **ca\_file** 
- **alpn\_protocols** 
- **server\_name** 
- **verify\_certificate** 
- **verify\_hostname** 

:::BlockQuote
Disabling certificate or hostname verification is strongly discouraged unless the security implications are fully understood.
:::