dydbassoc

Documentation

Overview

Package dydbassoc implements an assoc.Assoc based on AWS's DynamoDB.

Index

• Constants
• type Assoc
  • func (a *Assoc) BatchGet(ctx context.Context, batch assoc.Batch) error
  • func (a *Assoc) CollectWithThreshold(ctx context.Context, live liveset.Liveset, dead liveset.Liveset, ...) error
  • func (a *Assoc) Count(ctx context.Context) (int64, error)
  • func (a *Assoc) Delete(ctx context.Context, k digest.Digest) error
  • func (a *Assoc) Get(ctx context.Context, kind assoc.Kind, k digest.Digest) (digest.Digest, digest.Digest, error)
  • func (a *Assoc) Help() string
  • func (a *Assoc) Init(sess *session.Session, labels pool.Labels) error
  • func (a *Assoc) Scan(ctx context.Context, kinds []assoc.Kind, mappingHandler assoc.MappingHandler) error
  • func (a *Assoc) Setup(sess *session.Session, logger *log.Logger) error
  • func (a *Assoc) Store(ctx context.Context, kind assoc.Kind, k, v digest.Digest) error
  • func (a *Assoc) String() string
  • func (a *Assoc) Version() int
• type Items
• type ItemsHandler
• type ItemsHandlerFunc
  • func (h ItemsHandlerFunc) HandleItems(items Items) error

Constants

const (
	// ProviderName is the name of this Assoc's infra config provider.
	ProviderName = "dynamodbassoc"
)

Types

type Assoc

type Assoc struct {
	infra2.TableNameFlagsTrait
	DB      dynamodbiface.DynamoDBAPI `yaml:"-"`
	Limiter *limiter.Limiter          `yaml:"-"`
	// Labels to assign to cache entries.
	Labels pool.Labels `yaml:"-"`
	// contains filtered or unexported fields
}

Assoc implements a DynamoDB-backed Assoc for use in caches. Each association entry is represented by a DynamoDB item with the attributes "ID" and "Value".

func (*Assoc) BatchGet

func (a *Assoc) BatchGet(ctx context.Context, batch assoc.Batch) error

BatchGet implements the assoc interface. BatchGet will return a result for each key in the batch. BatchGet could internally split the keys into several batches. Any global errors, like context cancellation, S3 API errors or a key parse error would be returned from BatchGet. Any value parse errors would be returned as part of the result for that key.

func (*Assoc) CollectWithThreshold

func (a *Assoc) CollectWithThreshold(ctx context.Context, live liveset.Liveset, dead liveset.Liveset, threshold time.Time, rate int64, dryRun bool) error

CollectWithThreshold removes from this Assoc any objects whose keys are not in the liveset and have not been accessed more recently than the liveset's threshold

func (*Assoc) Count

func (a *Assoc) Count(ctx context.Context) (int64, error)

Count returns an estimate of the number of associations in this mapping

func (*Assoc) Delete

func (a *Assoc) Delete(ctx context.Context, k digest.Digest) error

Delete deletes the key k unconditionally from the provided assoc.

func (*Assoc) Get

func (a *Assoc) Get(ctx context.Context, kind assoc.Kind, k digest.Digest) (digest.Digest, digest.Digest, error)

Get returns the digest associated with key digest k. Lookup returns an error flagged errors.NotExist when no such mapping exists. Lookup also modifies the item's last-accessed time, which can be used for LRU object garbage collection. Get expands abbreviated keys by making use of a DynamoDB index.

func (*Assoc) Help

func (a *Assoc) Help() string

Help implements infra.Provider.

func (*Assoc) Init

func (a *Assoc) Init(sess *session.Session, labels pool.Labels) error

Init implements infra.Provider.

func (*Assoc) Scan

func (a *Assoc) Scan(ctx context.Context, kinds []assoc.Kind, mappingHandler assoc.MappingHandler) error

Scan calls the handler function for every association in the mapping. Note that the handler function may be called asynchronously from multiple threads.

func (*Assoc) Setup

func (a *Assoc) Setup(sess *session.Session, logger *log.Logger) error

Setup implements infra.Provider.

func (*Assoc) Store

func (a *Assoc) Store(ctx context.Context, kind assoc.Kind, k, v digest.Digest) error

Store associates the digest v with the key digest k of the provided kind. If v is zero, k's association for (kind,v) will be removed.

func (*Assoc) String

func (a *Assoc) String() string

func (*Assoc) Version

func (a *Assoc) Version() int

Version implements infra.Provider.

type Items

type Items []map[string]*dynamodb.AttributeValue

Items is the response from a dynamoDb scan.

type ItemsHandler

type ItemsHandler interface {
	// HandleItems handles a set of scanned items.
	HandleItems(items Items) error
}

ItemsHandler is an interface for handling Items from a segment scan.

type ItemsHandlerFunc

type ItemsHandlerFunc func(items Items) error

ItemsHandlerFunc is a convenience type to avoid having to declare a struct to implement the ItemsHandler interface.

func (ItemsHandlerFunc) HandleItems

func (h ItemsHandlerFunc) HandleItems(items Items) error

HandleItems implements the ItemsHandler interface.