affixed

Documentation

Overview

Package affixed implements a blob.KV that delegates to another implementation, with keys namespaced by a fixed prefix and/or suffix concatenated with each key.

Index

• type KV
  • func NewKV(kv blob.KV) KV
  • func (s KV) Base() blob.KV
  • func (s KV) Delete(ctx context.Context, key string) error
  • func (s KV) Derive(prefix, suffix string) KV
  • func (s KV) Get(ctx context.Context, key string) ([]byte, error)
  • func (s KV) Len(ctx context.Context) (int64, error)
  • func (s KV) List(ctx context.Context, start string, f func(string) error) error
  • func (s KV) Prefix() string
  • func (s KV) Put(ctx context.Context, opts blob.PutOptions) error
  • func (s KV) Suffix() string
  • func (s KV) UnwrapKey(key string) string
  • func (s KV) WithPrefix(prefix string) KV
  • func (s KV) WithSuffix(suffix string) KV
  • func (s KV) WrapKey(key string) string

Types

type KV

type KV struct {
	// contains filtered or unexported fields
}

KV implements the blob.KV interface by delegating to an underlying keyspace, but with each key prefixed and/or suffixed by fixed non-empty strings. This allows multiple consumers to share non-overlapping namespaces within a single KV.

func NewKV

func NewKV(kv blob.KV) KV

NewKV creates a KV associated with the specified kv. The initial value is exactly equivalent to the underlying store; use Derive to create clones that use a different prefix/suffix.

Affixes do not nest: If s is already a KV, it is returned as-is.

func (KV) Base

func (s KV) Base() blob.KV

Base returns the underlying store associated with s.

func (KV) Delete

func (s KV) Delete(ctx context.Context, key string) error

Delete implements part of blob.KV by delegation.

func (KV) Derive

func (s KV) Derive(prefix, suffix string) KV

Derive creates a clone of s that delegates to the same underlying store, but using a different prefix and suffix. If prefix == suffix == "", Derive returns a store that is equivalent to the original base store.

func (KV) Get

func (s KV) Get(ctx context.Context, key string) ([]byte, error)

Get implements part of blob.Store by delegation.

func (KV) Len

func (s KV) Len(ctx context.Context) (int64, error)

Len implements part of blob.KV by delegation. It reports only the number of keys matching the current prefix.

func (KV) List

func (s KV) List(ctx context.Context, start string, f func(string) error) error

List implements part of blob.KV by delegation. It filters the underlying list results to include only keys prefixed/suffixed for this store.

func (KV) Prefix

func (s KV) Prefix() string

Prefix returns the key prefix associated with s.

func (KV) Put

func (s KV) Put(ctx context.Context, opts blob.PutOptions) error

Put implements part of blob.KV by delegation.

func (KV) Suffix

func (s KV) Suffix() string

Suffix returns the key suffix associated with s.

func (KV) UnwrapKey

func (s KV) UnwrapKey(key string) string

UnwrapKey returns the unwrapped version of key with the current prefix and suffix removed (if present).

func (KV) WithPrefix

func (s KV) WithPrefix(prefix string) KV

WithPrefix creates a clone of s that delegates to the same underlying store, but using a different prefix. The suffix, if any, is unchanged.

func (KV) WithSuffix

func (s KV) WithSuffix(suffix string) KV

WithSuffix creates a clone of s that delegates to the same underlying store, but using a different suffix. The prefix, if any, is unchanged.

func (KV) WrapKey

func (s KV) WrapKey(key string) string

WrapKey returns the wrapped version of key as it would be stored into the base store with the current prefix and suffix attached.