GCP PubSub Sink

The Vector gcp_pubsub sink sends logs to GCP PubSub.

Configuration

Common
Advanced

vector.toml
vector.yaml
vector.json

[sinks.my_sink_id]
  # General
  type = "gcp_pubsub" # required
  inputs = ["my-source-or-transform-id"] # required
  credentials_path = "/path/to/credentials.json" # optional, no default
  project = "vector-123456" # required
  topic = "this-is-a-topic" # required

  # Encoding

  # Healthcheck
  healthcheck.enabled = true # optional, default

11 items

commonrequired

optionalstring
api_key
A Google Cloud API key used to authenticate access the pubsub project and topic. Either this or credentials_path must be set. See GCP Authentication for more info.
- View examples
optionaltable
batch
Configures the sink batching behavior.
- commonoptionaluint
  max_bytes
  The maximum size of a batch, in bytes, before it is flushed.
  - Default: 10485760 (bytes)
- commonoptionaluint
  max_events
  The maximum size of a batch, in events, before it is flushed. See Buffers & batches for more info.
  - Default: 1000 (events)
- commonoptionaluint
  timeout_secs
  The maximum age of a batch before it is flushed. See Buffers & batches for more info.
  - Default: 1 (seconds)
optionaltable
buffer
Configures the sink specific buffer behavior.
- commonoptionaluint
  max_events
  The maximum number of events allowed in the buffer. See Buffers & batches for more info.
  - Only relevant when: type = "memory"
  - Default: 500 (events)
- commonrequired*uint
  max_size
  The maximum size of the buffer on the disk. See Buffers & batches for more info.
  - Only required when: type = "disk"
  - View examples
- enumcommonoptionalstring
  type
  The buffer's type and storage mechanism.
  - Default: "memory"
  - Enum, must be one of: "memory" "disk"
  - View examples
- enumoptionalstring
  when_full
  The behavior when the buffer becomes full.
  - Default: "block"
  - Enum, must be one of: "block" "drop_newest"
  - View examples
commonoptionalstring
credentials_path
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. See GCP Authentication for more info.
- View examples
commonrequiredtable
encoding
Configures the encoding specific sink behavior.
- optional[string]
  except_fields
  Prevent the sink from encoding the specified labels.
  - View examples
- optional[string]
  only_fields
  Prevent the sink from encoding the specified labels.
  - View examples
- enumoptionalstring
  timestamp_format
  How to format event timestamps.
  - Default: "rfc3339"
  - Enum, must be one of: "rfc3339" "unix"
  - View examples
optionalstring
endpoint
The endpoint to which to send data.
- Default: "https://pubsub.googleapis.com"
- View examples
commonoptionaltable
healthcheck
Health check options for the sink. See Health checks for more info.
- commonoptionalbool
  enabled
  Enables/disables the healthcheck upon Vector boot.
  - Default: true
  - View examples
commonrequiredstring
project
The project name to which to publish logs.
- View examples
optionaltable
request
Configures the sink request behavior.
- optionaltable
  adaptive_concurrency
  Configure the adaptive concurrency algorithms. These values have been tuned by optimizing simulated results. In general you should not need to adjust these.
  - optionalfloat
    decrease_ratio
    The fraction of the current value to set the new concurrency limit when decreasing the limit. Valid values are greater than 0 and less than 1. Smaller values cause the algorithm to scale back rapidly when latency increases. Note that the new limit is rounded down after applying this ratio.
    - Default: 0.9
  - optionalfloat
    ewma_alpha
    The adaptive concurrency algorithm uses an exponentially weighted moving average (EWMA) of past RTT measurements as a reference to compare with the current RTT. This value controls how heavily new measurements are weighted compared to older ones. Valid values are greater than 0 and less than 1. Smaller values cause this reference to adjust more slowly, which may be useful if a service has unusually high response variability.
    - Default: 0.7
  - optionalfloat
    rtt_threshold_ratio
    When comparing the past RTT average to the current measurements, we ignore changes that are less than this ratio higher than the past RTT. Valid values are greater than or equal to 0. Larger values cause the algorithm to ignore larger increases in the RTT.
    - Default: 0.05
- commonoptionaluint
  concurrency
  The maximum number of in-flight requests allowed at any given time, or "auto" to allow Vector to automatically set the limit based on current network and service conditions.
  - Default: 5 (requests)
- commonoptionaluint
  rate_limit_duration_secs
  The time window, in seconds, used for the rate_limit_num option.
  - Default: 1 (seconds)
- commonoptionaluint
  rate_limit_num
  The maximum number of requests allowed within the rate_limit_duration_secs time window.
  - Default: 100
- optionaluint
  retry_attempts
  The maximum number of retries to make for failed requests. The default, for all intents and purposes, represents an infinite number of retries.
  - Default: 18446744073709552000
- optionaluint
  retry_initial_backoff_secs
  The amount of time to wait before attempting the first retry for a failed request. Once, the first retry has failed the fibonacci sequence will be used to select future backoffs.
  - Default: 1 (seconds)
- optionaluint
  retry_max_duration_secs
  The maximum amount of time, in seconds, to wait between retries.
  - Default: 10 (seconds)
- commonoptionaluint
  timeout_secs
  The maximum time a request can take before being aborted. It is highly recommended that you do not lower this value below the service's internal timeout, as this could create orphaned requests, pile on retries, and result in duplicate data downstream. See Buffers & batches for more info.
  - Default: 60 (seconds)
optionaltable
tls
Configures the TLS options for incoming connections.
- optionalstring
  ca_file
  Absolute path to an additional CA certificate file, in DER or PEM format (X.509), or an inline CA certificate in PEM format.
  - View examples
- commonoptionalstring
  crt_file
  Absolute path to a certificate file used to identify this connection, in DER or PEM format (X.509) or PKCS#12, or an inline certificate in PEM format. If this is set and is not a PKCS#12 archive, key_file must also be set.
  - View examples
- commonoptionalstring
  key_file
  Absolute path to a private key file used to identify this connection, in DER or PEM format (PKCS#8), or an inline private key in PEM format. If this is set, crt_file must also be set.
  - View examples
- optionalstring
  key_pass
  Pass phrase used to unlock the encrypted key file. This has no effect unless key_file is set.
  - View examples
- optionalbool
  verify_hostname
  If true (the default), Vector will validate the configured remote host name against the remote host's TLS certificate. Do NOT set this to false unless you understand the risks of not verifying the remote hostname.
  - Default: true
  - View examples
commonrequiredstring
topic
The topic within the project to which to publish logs.
- View examples

Env Vars

commonoptionalstring
GOOGLE_APPLICATION_CREDENTIALS
The filename for a Google Cloud service account credentials JSON file used for authentication. See GCP Authentication for more info.
- Only relevant when: endpoint = null
- View examples

Telemetry

This component provides the following metrics that can be retrieved through the internal_metrics source. See the metrics section in the monitoring page for more info.

counter
processed_events_total
The total number of events processed by this component. This metric includes the following tags:
- component_kind - The Vector component kind.
- component_name - The Vector component ID.
- component_type - The Vector component type.
- file - The file that produced the error
- instance - The Vector instance identified by host and port.
- job - The name of the job producing Vector metrics.
counter
processed_bytes_total
The total number of bytes processed by the component. This metric includes the following tags:
- component_kind - The Vector component kind.
- component_name - The Vector component ID.
- component_type - The Vector component type.
- instance - The Vector instance identified by host and port.
- job - The name of the job producing Vector metrics.

How It Works

Buffers & 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 <% if component.options.batch.children.respond_to?(:max_size) %>max_size<% else %>max_events<% end %>.

Buffers are controlled via the buffer.* options.

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 are not found the healtcheck will fail and an error will be 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.

Require health checks

If you'd like to exit immediately upon a health check failure, you can pass the --require-healthy flag:

vector --config /etc/vector/vector.toml --require-healthy

Disable health checks

If you'd like to disable health checks for this sink you can set the healthcheck option to false.

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:

vector.toml

[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

Adaptive Request Concurrency (ARC)

Adaptive Requst Concurrency is a feature of Vector that does away with static rate limits and automatically optimizes HTTP concurrency limits based on downstream service responses. The underlying mechanism is a feedback loop inspired by TCP congestion control algorithms. Checkout the announcement blog post,

We highly recommend enabling this feature as it improves performance and reliability of Vector and the systems it communicates with.

To enable, set the request.concurrency option to adaptive:

vector.toml

[sinks.my-sink]
  request.concurrency = "adaptive"

Static rate limits

If Adaptive Request Concurrency is not for you, you can manually set static rate limits with the request.rate_limit_duration_secs, request.rate_limit_num, and request.concurrency options:

vector.toml

[sinks.my-sink]
  request.rate_limit_duration_secs = 1
  request.rate_limit_num = 10
  request.concurrency = 10

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.

Transport Layer Security (TLS)

Vector uses Openssl for TLS protocols for it's maturity. You can enable and adjust TLS behavior via the tls.* options.

#Configuration

#api_key

#batch

#max_bytes

#max_events

#timeout_secs

#buffer

#max_events

#max_size

#type

#when_full

#credentials_path

#encoding

#except_fields

#only_fields

#timestamp_format

#endpoint

#healthcheck

#enabled

#project

#request

#adaptive_concurrency

#decrease_ratio

#ewma_alpha

#rtt_threshold_ratio

#concurrency

#rate_limit_duration_secs

#rate_limit_num

#retry_attempts

#retry_initial_backoff_secs

#retry_max_duration_secs

#timeout_secs

#tls

#ca_file

#crt_file

#key_file

#key_pass

#verify_hostname

#topic

#Env Vars

#GOOGLE_APPLICATION_CREDENTIALS

#Telemetry

#processed_events_total

#processed_bytes_total

#How It Works

#Buffers & batches

#GCP Authentication

#Health checks

#Require health checks

#Disable health checks

#Partitioning

#Rate limits & adapative concurrency

#Adaptive Request Concurrency (ARC)

#Static rate limits

#Retry policy

#Transport Layer Security (TLS)

Configuration

api_key

batch

max_bytes

max_events

timeout_secs

buffer

max_events

max_size

type

when_full

credentials_path

encoding

except_fields

only_fields

timestamp_format

endpoint

healthcheck

enabled

project

request

adaptive_concurrency

decrease_ratio

ewma_alpha

rtt_threshold_ratio

concurrency

rate_limit_duration_secs

rate_limit_num

retry_attempts

retry_initial_backoff_secs

retry_max_duration_secs

timeout_secs

tls

ca_file

crt_file

key_file

key_pass

verify_hostname

topic

Env Vars

GOOGLE_APPLICATION_CREDENTIALS

Telemetry

processed_events_total

processed_bytes_total

How It Works

Buffers & batches

GCP Authentication

Health checks

Require health checks

Disable health checks

Partitioning

Rate limits & adapative concurrency

Adaptive Request Concurrency (ARC)

Static rate limits

Retry policy

Transport Layer Security (TLS)