gcs-helper

README

gcs-helper

gcs-helper is inspired by s3-helper and is used to provide access to private GCS buckets.

It's intended to be deployed along with Kaltura's nginx-vod-module.

It also provides the needed support for the mapped mode (when using the proper environment variables - GCS_HELPER_PROXY_PREFIX, GCS_HELPER_MAP_PREFIX and GCS_HELPER_MAP_EXTENSIONS).

Configuration

The following environment variables control the behavior of gcs-helper:

Variable	Default value	Required	Description
GCS_HELPER_LISTEN	:8080	No	Address to bind the server
GCS_HELPER_BUCKET_NAME		Yes	Name of the bucket
GCS_HELPER_LOG_LEVEL	debug	No	Logging level
GCS_HELPER_PROXY_PREFIX		No	Prefix to use for the proxy binding. Required if running in map and proxy modes (example value: /proxy/)
GCS_HELPER_PROXY_TIMEOUT	10s	No	Defines the maximum time in serving the proxy requests, this is a hard timeout and includes retries
GCS_HELPER_MAP_PREFIX		No	Prefix to use for the map binding. Required if running in map and proxy modes (example value: /map/)
GCS_HELPER_MAP_EXTENSIONS		No	Comma separated list of extensions to include in the mapping (example value: .mp4,.vtt,.srt)

The are also some configuration variables for network communication with Google Cloud Storage API:

Variable	Default value	Required	Description
GCS_CLIENT_TIMEOUT	2s	No	Hard timeout on requests that gcs-helper sends to the Google Storage API
GCS_CLIENT_IDLE_CONN_TIMEOUT	120s	No	Maximum duration of idle connections between gcs-helper and the Google Storage API
GCS_CLIENT_MAX_IDLE_CONNS	10	No	Maximum number of idle connections to keep open. This doesn't control the maximum number of connections

GCS_HELPER_PROXY_TIMEOUT x GCS_CLIENT_TIMEOUT

The timeout configuration is mainly controlled by two environment variables: GCS_HELPER_PROXY_TIMEOUT and GCS_CLIENT_TIMEOUT. The GCS_HELPER_PROXY_TIMEOUT controls how long requests to gcs-helper can take, and GCS_CLIENT_TIMEOUT controls how long requests from gcs-helper to Google's API can take. Since gcs-helper automatically retries on failures, the number of retries is roughly the value of GCS_HELPER_PROXY_TIMEOUT divided by the value of GCS_CLIENT_TIMEOUT.