GCP Cloud Storage (GCS) Sink

The Vector gcp_cloud_storage sink batches log events to Google Cloud Platform's Cloud Storage service via the XML Interface.

Configuration

vector.toml
[sinks.my_sink_id]
# General
type = "gcp_cloud_storage" # required
inputs = ["my-source-id"] # required
compression = "gzip" # required
credentials_path = "/path/to/credentials.json" # optional, no default
healthcheck = true # optional, default
# Buffer
buffer.type = "memory" # optional, default
buffer.max_events = 500 # optional, default, events, relevant when type = "memory"
# Encoding
encoding.codec = "ndjson" # required
# Object Names
key_prefix = "date=%F/" # optional, default
  • tableoptional

    batch

    Configures the sink batching behavior.

    • int (bytes)commonoptional

      max_size

      The maximum size of a batch, in bytes, before it is flushed.

      See Buffers & Batches for more info.

      • Default: 10485760 (bytes)
      • View examples
    • int (seconds)commonoptional

      timeout_secs

      The maximum age of a batch before it is flushed.

      See Buffers & Batches for more info.

      • Default: 300 (seconds)
      • View examples
  • tablecommonoptional

    buffer

    Configures the sink specific buffer behavior.

    • stringenumcommonoptional

      type

      The buffer's type and storage mechanism.

      • Default: "memory"
      • Enum, must be one of: "memory" "disk"
      • View examples
    • int (events)commonoptional

      max_events

      The maximum number of events allowed in the buffer.

      • Only relevant when: type = "memory"
      • Default: 500 (events)
      • View examples
    • int (bytes)required*

      max_size

      The maximum size of the buffer on the disk.

      See Buffers & Batches for more info.

      • Only required when: type = "disk"
      • No default
      • View examples
    • stringenumoptional

      when_full

      The behavior when the buffer becomes full.

      • Default: "block"
      • Enum, must be one of: "block" "drop_newest"
      • View examples
  • tablecommonrequired

    encoding

    Configures the encoding specific sink behavior.

    • stringenumcommonrequired

      codec

      The encoding codec used to serialize the events before outputting.

      • No default
      • Enum, must be one of: "ndjson" "text"
      • View examples
    • [string]optional

      except_fields

      Prevent the sink from encoding the specified labels.

      • No default
      • View examples
    • [string]optional

      only_fields

      Limit the sink to only encoding the specified labels.

      • No default
      • View examples
    • stringenumoptional

      timestamp_format

      How to format event timestamps.

      • Default: "rfc3339"
      • Enum, must be one of: "rfc3339" "unix"
      • View examples
  • stringrequired

    bucket

    The GCS bucket name.

    • No default
    • View examples
  • stringenumcommonrequired

    compression

    The compression mechanism to use.

    • No default
    • Enum, must be one of: "gzip" "none"
    • View examples
  • stringcommonoptional

    credentials_path

    The filename for a Google Cloud service account credentials JSON file used to authenticate access to the Cloud Storage API. 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.

    • No default
    • View examples
  • boolcommonoptional

    healthcheck

    Enables/disables the sink healthcheck upon start.

    See Health Checks for more info.

    • Default: true
    • View examples
  • stringenumoptional

    acl

    Predefined ACL to apply to the created objects. For more information, see Predefined ACLs. If this is not set, GCS will apply a default ACL when the object is created.

    See Object access control list (ACL) for more info.

    • No default
    • Enum, must be one of: "authenticatedRead" "bucketOwnerFullControl" "bucketOwnerRead" "private" "projectPrivate" "publicRead"
    • View examples
  • stringoptional

    metadata

    The set of metadata key:value pairs for the created objects. See the GCS custom metadata documentation for more details.

    • stringoptional

      [key-name]

      A custom metadata item to be added to the created objects.

      • No default
      • View examples
  • stringenumoptional

    storage_class

    The storage class for the created objects. See the GCP storage classes for more details.

    See Storage class for more info.

    • No default
    • Enum, must be one of: "STANDARD" "NEARLINE" "COLDLINE" "ARCHIVE"
    • View examples
  • booloptional

    filename_append_uuid

    Whether or not to append a UUID v4 token to the end of the file. This ensures there are no name collisions high volume use cases.

    See Object naming for more info.

    • Default: true
    • View examples
  • stringoptional

    filename_extension

    The filename extension to use in the object name.

    • Default: "log"
    • View examples
  • stringoptional

    filename_time_format

    The format of the resulting object file name. strftime specifiers are supported.

    See Object naming for more info.

    • Default: "%s"
    • View examples
  • templateablestringcommonoptional

    key_prefix

    A prefix to apply to all object key names. This should be used to partition your objects, and it's important to end this value with a / if you want this to be the root GCS "folder".

    See Object naming, Partitioning, and Template Syntax for more info.

    • Default: "date=%F/"
    • View examples
  • tableoptional

    request

    Configures the sink request behavior.

    • int (requests)commonoptional

      in_flight_limit

      The maximum number of in-flight requests allowed at any given time.

      See Rate Limits for more info.

      • Default: 5 (requests)
      • View examples
    • int (seconds)commonoptional

      rate_limit_duration_secs

      The time window, in seconds, used for the rate_limit_num option.

      See Rate Limits for more info.

      • Default: 1 (seconds)
      • View examples
    • intcommonoptional

      rate_limit_num

      The maximum number of requests allowed within the rate_limit_duration_secs time window.

      See Rate Limits for more info.

      • Default: 1000
      • View examples
    • intoptional

      retry_attempts

      The maximum number of retries to make for failed requests.

      See Retry Policy for more info.

      • Default: -1
      • View examples
    • int (seconds)optional

      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)
      • View examples
    • int (seconds)optional

      retry_max_duration_secs

      The maximum amount of time, in seconds, to wait between retries.

      • Default: 10 (seconds)
      • View examples
    • int (seconds)commonoptional

      timeout_secs

      The maximum time a request can take before being aborted. It is highly recommended that you do not lower 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)
      • View examples
  • tableoptional

    tls

    Configures the TLS options for connections from this sink.

    • stringoptional

      ca_path

      Absolute path to an additional CA certificate file, in DER or PEM format (X.509).

      • No default
      • View examples
    • stringcommonoptional

      crt_path

      Absolute path to a certificate file used to identify this connection, in DER or PEM format (X.509) or PKCS#12. If this is set and is not a PKCS#12 archive, key_path must also be set.

      • No default
      • View examples
    • stringoptional

      key_pass

      Pass phrase used to unlock the encrypted key file. This has no effect unless key_path is set.

      • No default
      • View examples
    • stringcommonoptional

      key_path

      Absolute path to a certificate key file used to identify this connection, in DER or PEM format (PKCS#8). If this is set, crt_path must also be set.

      • No default
      • View examples
    • booloptional

      verify_certificate

      If true (the default), Vector will validate the TLS certificate of the remote host.

      • WARNING: Setting this to `false` means the certificate will be loaded and checked for validity, but the handshake will not attempt to verify the certificate. Do NOT set this to `false` unless you understand the risks of not verifying the remote certificate.
      • Default: true
      • View examples
    • booloptional

      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

Env Vars

  • stringcommonoptional

    GOOGLE_APPLICATION_CREDENTIALS

    The filename for a Google Cloud service account credentials JSON file used to authenticate access to the Cloud Storage API.

    • No default
    • View examples

How It Works

Buffers & Batches

The gcp_cloud_storage sink 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:

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

Buffers are controlled via the buffer.* options.

Environment Variables

Environment variables are supported through all of Vector's configuration. Simply add ${MY_ENV_VAR} in your Vector configuration file and the variable will be replaced before being evaluated.

You can learn more in the Environment Variables section.

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.

Object access control list (ACL)

GCP Cloud Storage supports access control lists (ACL) for buckets and objects. In the context of Vector, only object ACLs are relevant (Vector does not create or modify buckets). You can set the object level ACL by using the acl option, which allows you to set one of the predefined ACLs on each created object.

Object naming

By default, Vector will name your GCS objects in the following format:

<key_prefix><timestamp>-<uuidv4>.log

For example:

date=2019-06-18/1560886634-fddd7a0e-fad9-4f7e-9bce-00ae5debc563.log

Vector appends a UUIDV4 token to ensure there are no name conflicts in the unlikely event 2 Vector instances are writing data at the same time.

You can control the resulting name via the key_prefix, filename_time_format, and filename_append_uuid options.

Partitioning

Partitioning is controlled via the key_prefix options and allows you to dynamically partition data on the fly. You'll notice that Vector's template sytax is supported for these options, enabling you to use field values as partition keys.

Rate Limits

Vector offers a few levers to control the rate and volume of requests to the downstream service. Start with the rate_limit_duration_secs and rate_limit_num options to ensure Vector does not exceed the specified number of requests in the specified window. You can further control the pace at which this window is saturated with the in_flight_limit option, which will guarantee no more than the specified number of requests are in-flight at any given time.

Please note, Vector's defaults are carefully chosen and it should be rare that you need to adjust these. If you found a good reason to do so please share it with the Vector team by opening an issue.

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 retry_attempts and retry_backoff_secs options.

Storage class

GCS offers storage classes. You can apply defaults, and rules, at the bucket level or set the storage class at the object level. In the context of Vector only the object level is relevant (Vector does not create or modify buckets). You can set the storage class via the storage_class option.

TLS

Vector uses Openssl for TLS protocols for it's battle-tested and reliable security. You can enable and adjust TLS behavior via the tls.* options.

Tags & metadata

Vector supports adding custom metadata to created objects. These metadata items are a way of associating extra data items with the object that are not part of the uploaded data.

Template Syntax

The key_prefix options support Vector's template syntax, enabling dynamic values derived from the event's data. This syntax accepts strptime specifiers as well as the {{ field_name }} syntax for accessing event fields. For example:

vector.toml
[sinks.my_gcp_cloud_storage_sink_id]
# ...
key_prefix = "date=%F/"
key_prefix = "date=%F/hour=%H/"
key_prefix = "year=%Y/month=%m/day=%d/"
key_prefix = "application_id={{ application_id }}/date=%F/"
# ...

You can learn more about the complete syntax in the templating reference.