GCP PubSub

Configuration Options

Required Options

project(required)

The project name to which to publish logs.

Type	Syntax	Default	Example
string	literal		["vector-123456"]

inputs(required)

A list of upstream source or transform IDs. Wildcards (*) are supported.

See configuration for more info.

Type	Syntax	Default	Example
array	literal		["my-source-or-transform-id","prefix-*"]

encoding(required)

Configures the encoding specific sink behavior.

Type	Syntax	Default	Example
hash	literal		[]

topic(required)

The topic within the project to which to publish logs.

Type	Syntax	Default	Example
string	literal		["this-is-a-topic"]

type(required)

The component type. This is a required field for all components and tells Vector which component to use.

Type	Syntax	Default	Example
string	literal		["gcp_pubsub"]

Advanced Options

api_key(optional)

A Google Cloud API key used to authenticate access the pubsub project and topic. Either this or credentials_path must be set.

Type	Syntax	Default	Example
string	literal		["${GCP_API_KEY}","ef8d5de700e7989468166c40fc8a0ccd"]

credentials_path(optional)

The filename for a Google Cloud service account credentials JSON file used to authenticate access to the pubsub project and topic. If this is unset, Vector checks the GOOGLE_APPLICATION_CREDENTIALS environment variable for a filename.

If no filename is named, Vector will attempt to fetch an instance service account for the compute instance the program is running on. If Vector is not running on a GCE instance, you must define a credentials file as above.

Type	Syntax	Default	Example
string	literal		["/path/to/credentials.json"]

endpoint(optional)

The endpoint to which to send data.

Type	Syntax	Default	Example
string	literal	https://pubsub.googleapis.com	["https://us-central1-pubsub.googleapis.com"]

buffer(optional)

Configures the sink specific buffer behavior.

Type	Syntax	Default	Example
hash	literal		[]

batch(optional)

Configures the sink batching behavior.

Type	Syntax	Default	Example
hash			[]

healthcheck(optional)

Health check options for the sink.

Type	Syntax	Default	Example
hash			[]

request(optional)

Configures the sink request behavior.

Type	Syntax	Default	Example
hash			[]

tls(optional)

Configures the TLS options for incoming connections.

Type	Syntax	Default	Example
hash	literal		[]

proxy(optional)

Configures an HTTP(S) proxy for Vector to use. By default, the globally configured proxy is used.

Type	Syntax	Default	Example
hash	literal		[]

How it Works

State

This component is stateless, meaning its behavior is consistent across each input.

GCP Authentication

GCP offers a variety of authentication methods and Vector is concerned with the server to server methods and will find credentials in the following order:

If the credentials_path option is set.
If the api_key option is set.
If the GOOGLE_APPLICATION_CREDENTIALS envrionment variable is set.
Finally, Vector will check for an instance service account.

If credentials aren't found, Vector's health checks fail and an error is logged.

Health checks

Health checks ensure that the downstream service is accessible and ready to accept data. This check is performed upon sink initialization. If the health check fails an error will be logged and Vector will proceed to start.

Partitioning

Vector supports dynamic configuration values through a simple template syntax. If an option supports templating, it will be noted with a badge and you can use event fields to create dynamic values. For example:

[sinks.my-sink]
dynamic_option = "application={{ application_id }}"

In the above example, the application_id for each event will be used to partition outgoing data.

Rate limits & adapative concurrency

Transport Layer Security (TLS)

Vector uses OpenSSL for TLS protocols due to OpenSSL's maturity. You can enable and adjust TLS behavior using the tls.* options.

Buffers and batches

This component buffers & batches data as shown in the diagram above. You'll notice that Vector treats these concepts differently, instead of treating them as global concepts, Vector treats them as sink specific concepts. This isolates sinks, ensuring services disruptions are contained and delivery guarantees are honored.

Batches are flushed when 1 of 2 conditions are met:

The batch age meets or exceeds the configured timeout_secs.
The batch size meets or exceeds the configured max_size or max_events.

Buffers are controlled via the buffer.* options.

Retry policy

Vector will retry failed requests (status == 429, >= 500, and != 501). Other responses will not be retried. You can control the number of retry attempts and backoff rate with the request.retry_attempts and request.retry_backoff_secs options.