57 lines
1.8 KiB
Go
57 lines
1.8 KiB
Go
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// Package state holds the interface that any state implementation for
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// IPFS Cluster must satisfy.
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package state
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// State represents the shared state of the cluster
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import (
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"context"
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"errors"
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"io"
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"github.com/ipfs-cluster/ipfs-cluster/api"
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)
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// ErrNotFound should be returned when a pin is not part of the state.
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var ErrNotFound = errors.New("pin is not part of the pinset")
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// State is a wrapper to the Cluster shared state so that Pin objects can
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// be easily read, written and queried. The state can be marshaled and
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// unmarshaled. Implementation should be thread-safe.
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type State interface {
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ReadOnly
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WriteOnly
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// Migrate restores the serialized format of an outdated state to the
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// current version.
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Migrate(ctx context.Context, r io.Reader) error
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// Marshal serializes the state to a byte slice.
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Marshal(io.Writer) error
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// Unmarshal deserializes the state from marshaled bytes.
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Unmarshal(io.Reader) error
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}
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// ReadOnly represents the read side of a State.
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type ReadOnly interface {
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// List lists all the pins in the state.
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List(context.Context, chan<- api.Pin) error
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// Has returns true if the state is holding information for a Cid.
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Has(context.Context, api.Cid) (bool, error)
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// Get returns the information attacthed to this pin, if any. If the
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// pin is not part of the state, it should return ErrNotFound.
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Get(context.Context, api.Cid) (api.Pin, error)
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}
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// WriteOnly represents the write side of a State.
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type WriteOnly interface {
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// Add adds a pin to the State
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Add(context.Context, api.Pin) error
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// Rm removes a pin from the State.
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Rm(context.Context, api.Cid) error
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}
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// BatchingState represents a state which batches write operations.
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type BatchingState interface {
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State
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// Commit writes any batched operations.
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Commit(context.Context) error
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}
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