storage

README

Storage

A storage extension persists state beyond the collector process. Other components can request a storage client from the storage extension and use it to manage state.

The storage.Extension interface extends component.Extension by adding the following method:

GetClient(context.Context, component.Kind, config.ComponentID, string) (Client, error)

The storage.Client interface contains the following methods:

Get(context.Context, string) ([]byte, error)
Set(context.Context, string, []byte) error
Delete(context.Context, string) error
Close(context.Context) error

Note: All methods should return error only if a problem occurred. (For example, if a file is no longer accessible, or if a remote service is unavailable.)

Note: It is the responsibility of each component to Close a storage client that it has requested.

Documentation

Overview

Package stanzareceiver implements a receiver that can be used by the Opentelemetry collector to receive logs using the stanza log agent

Index

• type Client
  • func NewNopClient() Client
• type Extension

Types

type Client

type Client interface {

	// Get will retrieve data from storage that corresponds to the
	// specified key. It should return nil, nil if not found
	Get(context.Context, string) ([]byte, error)

	// Set will store data. The data can be retrieved by the same
	// component after a process restart, using the same key
	Set(context.Context, string, []byte) error

	// Delete will delete data associated with the specified key
	Delete(context.Context, string) error

	// Close will release any resources held by the client
	Close(context.Context) error
}

Client is the interface that storage clients must implement All methods should return error only if a problem occurred. This mirrors the behavior of a golang map:

• Set doesn't error if a key already exists - it just overwrites the value.
• Get doesn't error if a key is not found - it just returns nil.
• Delete doesn't error if the key doesn't exist - it just no-ops.

This also provides a way to differentiate data operations

[overwrite | not-found | no-op] from "real" problems

func NewNopClient

func NewNopClient() Client

NewNopClient returns a nop client

type Extension

type Extension interface {
	component.Extension

	// GetClient will create a client for use by the specified component.
	// The component can use the client to manage state
	GetClient(context.Context, component.Kind, config.ComponentID, string) (Client, error)
}

Extension is the interface that storage extensions must implement