Documentation ¶
Overview ¶
Package storage exposes the policy engine's storage layer.
Index ¶
- Constants
- Variables
- func IsIndexingNotSupported(err error) bool
- func IsInvalidPatch(err error) bool
- func IsInvalidTransaction(err error) bool
- func IsNotFound(err error) bool
- func IsWriteConflictError(err error) bool
- func MakeDir(ctx context.Context, store Store, txn Transaction, path Path) (err error)
- func NonEmpty(ctx context.Context, store Store, txn Transaction) func([]string) (bool, error)
- func ReadOne(ctx context.Context, store Store, path Path) (interface{}, error)
- func Txn(ctx context.Context, store Store, params TransactionParams, ...) error
- func WriteOne(ctx context.Context, store Store, op PatchOp, path Path, value interface{}) error
- type Context
- type DataEvent
- type Error
- type PatchOp
- type Path
- type Policy
- type PolicyEvent
- type PolicyNotSupported
- func (PolicyNotSupported) DeletePolicy(context.Context, Transaction, string) error
- func (PolicyNotSupported) GetPolicy(context.Context, Transaction, string) ([]byte, error)
- func (PolicyNotSupported) ListPolicies(context.Context, Transaction) ([]string, error)
- func (PolicyNotSupported) UpsertPolicy(context.Context, Transaction, string, []byte) error
- type Store
- type Transaction
- type TransactionParams
- type Trigger
- type TriggerConfig
- type TriggerEvent
- type TriggerHandle
- type TriggersNotSupported
- type WritesNotSupported
Constants ¶
const ( // InternalErr indicates an unknown, internal error has occurred. InternalErr = "storage_internal_error" // NotFoundErr indicates the path used in the storage operation does not // locate a document. NotFoundErr = "storage_not_found_error" // WriteConflictErr indicates a write on the path enocuntered a conflicting // value inside the transaction. WriteConflictErr = "storage_write_conflict_error" // InvalidPatchErr indicates an invalid patch/write was issued. The patch // was rejected. InvalidPatchErr = "storage_invalid_patch_error" // InvalidTransactionErr indicates an invalid operation was performed // inside of the transaction. InvalidTransactionErr = "storage_invalid_txn_error" // TriggersNotSupportedErr indicates the caller attempted to register a // trigger against a store that does not support them. TriggersNotSupportedErr = "storage_triggers_not_supported_error" // WritesNotSupportedErr indicate the caller attempted to perform a write // against a store that does not support them. WritesNotSupportedErr = "storage_writes_not_supported_error" // PolicyNotSupportedErr indicate the caller attempted to perform a policy // management operation against a store that does not support them. PolicyNotSupportedErr = "storage_policy_not_supported_error" // IndexingNotSupportedErr indicate the caller attempted to perform an // indexing operation against a store that does not support them. IndexingNotSupportedErr = "storage_indexing_not_supported_error" )
const ( AddOp PatchOp = iota RemoveOp = iota ReplaceOp = iota )
Patch supports add, remove, and replace operations.
Variables ¶
var WriteParams = TransactionParams{ Write: true, }
WriteParams specifies the TransactionParams for a write transaction.
Functions ¶
func IsIndexingNotSupported ¶ added in v0.5.0
IsIndexingNotSupported returns true if this error is a IndexingNotSupportedErr.
func IsInvalidPatch ¶ added in v0.2.0
IsInvalidPatch returns true if this error is a InvalidPatchErr.
func IsInvalidTransaction ¶ added in v0.5.0
IsInvalidTransaction returns true if this error is a InvalidTransactionErr.
func IsNotFound ¶
IsNotFound returns true if this error is a NotFoundErr.
func IsWriteConflictError ¶ added in v0.8.0
IsWriteConflictError returns true if this error a WriteConflictErr.
func MakeDir ¶ added in v0.8.0
MakeDir inserts an empty object at path. If the parent path does not exist, MakeDir will create it recursively.
func NonEmpty ¶ added in v0.10.4
NonEmpty returns a function that tests if a path is non-empty. A path is non-empty if a Read on the path returns a value or a Read on any of the path prefixes returns a non-object value.
func ReadOne ¶ added in v0.5.3
ReadOne is a convenience function to read a single value from the provided Store. It will create a new Transaction to perform the read with, and clean up after itself should an error occur.
func Txn ¶ added in v0.5.9
func Txn(ctx context.Context, store Store, params TransactionParams, f func(Transaction) error) error
Txn is a convenience function that executes f inside a new transaction opened on the store. If the function returns an error, the transaction is aborted and the error is returned. Otherwise, the transaction is committed and the result of the commit is returned.
Types ¶
type Context ¶ added in v0.12.2
type Context struct {
// contains filtered or unexported fields
}
Context is a simple container for key/value pairs.
func NewContext ¶ added in v0.12.2
func NewContext() *Context
NewContext returns a new context object.
type Path ¶ added in v0.3.0
type Path []string
Path refers to a document in storage.
func MustParsePath ¶ added in v0.3.0
MustParsePath returns a new Path for s. If s cannot be parsed, this function will panic. This is mostly for test purposes.
func NewPathForRef ¶ added in v0.3.0
NewPathForRef returns a new path for the given ref.
func ParsePathEscaped ¶ added in v0.8.1
ParsePathEscaped returns a new path for the given escaped str.
func (Path) Compare ¶ added in v0.3.0
Compare performs lexigraphical comparison on p and other and returns -1 if p is less than other, 0 if p is equal to other, or 1 if p is greater than other.
type Policy ¶ added in v0.5.0
type Policy interface { ListPolicies(context.Context, Transaction) ([]string, error) GetPolicy(context.Context, Transaction, string) ([]byte, error) UpsertPolicy(context.Context, Transaction, string, []byte) error DeletePolicy(context.Context, Transaction, string) error }
Policy defines the interface for policy module storage.
type PolicyEvent ¶ added in v0.5.3
PolicyEvent describes a change to a policy.
type PolicyNotSupported ¶ added in v0.5.0
type PolicyNotSupported struct{}
PolicyNotSupported provides a default implementation of the policy interface which may be used if the backend does not support policy storage.
func (PolicyNotSupported) DeletePolicy ¶ added in v0.5.0
func (PolicyNotSupported) DeletePolicy(context.Context, Transaction, string) error
DeletePolicy always returns a PolicyNotSupportedErr.
func (PolicyNotSupported) GetPolicy ¶ added in v0.5.0
func (PolicyNotSupported) GetPolicy(context.Context, Transaction, string) ([]byte, error)
GetPolicy always returns a PolicyNotSupportedErr.
func (PolicyNotSupported) ListPolicies ¶ added in v0.5.0
func (PolicyNotSupported) ListPolicies(context.Context, Transaction) ([]string, error)
ListPolicies always returns a PolicyNotSupportedErr.
func (PolicyNotSupported) UpsertPolicy ¶ added in v0.5.0
func (PolicyNotSupported) UpsertPolicy(context.Context, Transaction, string, []byte) error
UpsertPolicy always returns a PolicyNotSupportedErr.
type Store ¶ added in v0.2.0
type Store interface { Trigger Policy // NewTransaction is called create a new transaction in the store. NewTransaction(ctx context.Context, params ...TransactionParams) (Transaction, error) // Read is called to fetch a document referred to by path. Read(ctx context.Context, txn Transaction, path Path) (interface{}, error) // Write is called to modify a document referred to by path. Write(ctx context.Context, txn Transaction, op PatchOp, path Path, value interface{}) error // Commit is called to finish the transaction. If Commit returns an error, the // transaction must be automatically aborted by the Store implementation. Commit(ctx context.Context, txn Transaction) error // Abort is called to cancel the transaction. Abort(ctx context.Context, txn Transaction) }
Store defines the interface for the storage layer's backend.
type Transaction ¶ added in v0.2.0
type Transaction interface {
ID() uint64
}
Transaction defines the interface that identifies a consistent snapshot over the policy engine's storage layer.
func NewTransactionOrDie ¶ added in v0.2.0
func NewTransactionOrDie(ctx context.Context, store Store, params ...TransactionParams) Transaction
NewTransactionOrDie is a helper function to create a new transaction. If the storage layer cannot create a new transaction, this function will panic. This function should only be used for tests.
type TransactionParams ¶ added in v0.3.0
type TransactionParams struct { // Write indicates if this transaction will perform any write operations. Write bool // Context contains key/value pairs passed to triggers. Context *Context }
TransactionParams describes a new transaction.
type Trigger ¶ added in v0.2.0
type Trigger interface {
Register(ctx context.Context, txn Transaction, config TriggerConfig) (TriggerHandle, error)
}
Trigger defines the interface that stores implement to register for change notifications when the store is changed.
type TriggerConfig ¶ added in v0.2.0
type TriggerConfig struct { // OnCommit is invoked when a transaction is successfully committed. The // callback is invoked with a handle to the write transaction that // successfully committed before other clients see the changes. OnCommit func(ctx context.Context, txn Transaction, event TriggerEvent) }
TriggerConfig contains the trigger registration configuration.
type TriggerEvent ¶ added in v0.5.0
type TriggerEvent struct { Policy []PolicyEvent Data []DataEvent Context *Context }
TriggerEvent describes the changes that caused the trigger to be invoked.
func (TriggerEvent) DataChanged ¶ added in v0.5.0
func (e TriggerEvent) DataChanged() bool
DataChanged returns true if the trigger was caused by a data change.
func (TriggerEvent) IsZero ¶ added in v0.5.0
func (e TriggerEvent) IsZero() bool
IsZero returns true if the TriggerEvent indicates no changes occurred. This function is primarily for test purposes.
func (TriggerEvent) PolicyChanged ¶ added in v0.5.0
func (e TriggerEvent) PolicyChanged() bool
PolicyChanged returns true if the trigger was caused by a policy change.
type TriggerHandle ¶ added in v0.5.3
type TriggerHandle interface {
Unregister(ctx context.Context, txn Transaction)
}
TriggerHandle defines the interface that can be used to unregister triggers that have been registered on a Store.
type TriggersNotSupported ¶ added in v0.2.0
type TriggersNotSupported struct{}
TriggersNotSupported provides default implementations of the Trigger interface which may be used if the backend does not support triggers.
func (TriggersNotSupported) Register ¶ added in v0.2.0
func (TriggersNotSupported) Register(context.Context, Transaction, TriggerConfig) (TriggerHandle, error)
Register always returns an error indicating triggers are not supported.
type WritesNotSupported ¶ added in v0.2.0
type WritesNotSupported struct{}
WritesNotSupported provides a default implementation of the write interface which may be used if the backend does not support writes.
func (WritesNotSupported) Write ¶ added in v0.2.0
func (WritesNotSupported) Write(ctx context.Context, txn Transaction, op PatchOp, path Path, value interface{}) error