Documentation

Overview

    Interfaces for database-related operations.

    Index

    Constants

    View Source
    const (
    	ErrCodeKeyNotFound int = iota + 1
    	ErrCodeKeyExists
    	ErrCodeResourceVersionConflicts
    	ErrCodeInvalidObj
    	ErrCodeUnreachable
    )

    Variables

    View Source
    var Everything = SelectionPredicate{
    	Label: labels.Everything(),
    	Field: fields.Everything(),
    }

      Everything accepts all objects.

      Functions

      func DefaultClusterScopedAttr

      func DefaultClusterScopedAttr(obj runtime.Object) (labels.Set, fields.Set, error)

      func DefaultNamespaceScopedAttr

      func DefaultNamespaceScopedAttr(obj runtime.Object) (labels.Set, fields.Set, error)

      func EverythingFunc

      func EverythingFunc(runtime.Object) bool

      func IsConflict

      func IsConflict(err error) bool

        IsConflict returns true if and only if err is a write conflict.

        func IsInternalError

        func IsInternalError(err error) bool

          IsInternalError returns true if and only if err is an InternalError.

          func IsInvalidError

          func IsInvalidError(err error) bool

            IsInvalidError returns true if and only if err is an InvalidError.

            func IsInvalidObj

            func IsInvalidObj(err error) bool

              IsInvalidObj returns true if and only if err is invalid error

              func IsNodeExist

              func IsNodeExist(err error) bool

                IsNodeExist returns true if and only if err is an node already exist error.

                func IsNotFound

                func IsNotFound(err error) bool

                  IsNotFound returns true if and only if err is "key" not found error.

                  func IsUnreachable

                  func IsUnreachable(err error) bool

                    IsUnreachable returns true if and only if err indicates the server could not be reached.

                    func NamespaceKeyFunc

                    func NamespaceKeyFunc(prefix string, obj runtime.Object) (string, error)

                    func NoNamespaceKeyFunc

                    func NoNamespaceKeyFunc(prefix string, obj runtime.Object) (string, error)

                    Types

                    type AttrFunc

                    type AttrFunc func(obj runtime.Object) (labels.Set, fields.Set, error)

                      AttrFunc returns label and field sets and the uninitialized flag for List or Watch to match. In any failure to parse given object, it returns error.

                      func (AttrFunc) WithFieldMutation

                      func (f AttrFunc) WithFieldMutation(fieldMutator FieldMutationFunc) AttrFunc

                      type FieldMutationFunc

                      type FieldMutationFunc func(obj runtime.Object, fieldSet fields.Set) error

                        FieldMutationFunc allows the mutation of the field selection fields. It is mutating to avoid the extra allocation on this common path

                        type HighWaterMark

                        type HighWaterMark int64

                          HighWaterMark is a thread-safe object for tracking the maximum value seen for some quantity.

                          func (*HighWaterMark) Update

                          func (hwm *HighWaterMark) Update(current int64) bool

                            Update returns true if and only if 'current' is the highest value ever seen.

                            type Interface

                            type Interface interface {
                            	// Returns Versioner associated with this interface.
                            	Versioner() Versioner
                            
                            	// Create adds a new object at a key unless it already exists. 'ttl' is time-to-live
                            	// in seconds (0 means forever). If no error is returned and out is not nil, out will be
                            	// set to the read value from database.
                            	Create(ctx context.Context, key string, obj, out runtime.Object, ttl uint64) error
                            
                            	// Delete removes the specified key and returns the value that existed at that spot.
                            	// If key didn't exist, it will return NotFound storage error.
                            	Delete(ctx context.Context, key string, out runtime.Object, preconditions *Preconditions) error
                            
                            	// Watch begins watching the specified key. Events are decoded into API objects,
                            	// and any items selected by 'p' are sent down to returned watch.Interface.
                            	// resourceVersion may be used to specify what version to begin watching,
                            	// which should be the current resourceVersion, and no longer rv+1
                            	// (e.g. reconnecting without missing any updates).
                            	// If resource version is "0", this interface will get current object at given key
                            	// and send it in an "ADDED" event, before watch starts.
                            	Watch(ctx context.Context, key string, resourceVersion string, p SelectionPredicate) (watch.Interface, error)
                            
                            	// WatchList begins watching the specified key's items. Items are decoded into API
                            	// objects and any item selected by 'p' are sent down to returned watch.Interface.
                            	// resourceVersion may be used to specify what version to begin watching,
                            	// which should be the current resourceVersion, and no longer rv+1
                            	// (e.g. reconnecting without missing any updates).
                            	// If resource version is "0", this interface will list current objects directory defined by key
                            	// and send them in "ADDED" events, before watch starts.
                            	WatchList(ctx context.Context, key string, resourceVersion string, p SelectionPredicate) (watch.Interface, error)
                            
                            	// Get unmarshals json found at key into objPtr. On a not found error, will either
                            	// return a zero object of the requested type, or an error, depending on ignoreNotFound.
                            	// Treats empty responses and nil response nodes exactly like a not found error.
                            	// The returned contents may be delayed, but it is guaranteed that they will
                            	// be have at least 'resourceVersion'.
                            	Get(ctx context.Context, key string, resourceVersion string, objPtr runtime.Object, ignoreNotFound bool) error
                            
                            	// GetToList unmarshals json found at key and opaque it into *List api object
                            	// (an object that satisfies the runtime.IsList definition).
                            	// The returned contents may be delayed, but it is guaranteed that they will
                            	// be have at least 'resourceVersion'.
                            	GetToList(ctx context.Context, key string, resourceVersion string, p SelectionPredicate, listObj runtime.Object) error
                            
                            	// List unmarshalls jsons found at directory defined by key and opaque them
                            	// into *List api object (an object that satisfies runtime.IsList definition).
                            	// The returned contents may be delayed, but it is guaranteed that they will
                            	// be have at least 'resourceVersion'.
                            	List(ctx context.Context, key string, resourceVersion string, p SelectionPredicate, listObj runtime.Object) error
                            
                            	// GuaranteedUpdate keeps calling 'tryUpdate()' to update key 'key' (of type 'ptrToType')
                            	// retrying the update until success if there is index conflict.
                            	// Note that object passed to tryUpdate may change across invocations of tryUpdate() if
                            	// other writers are simultaneously updating it, so tryUpdate() needs to take into account
                            	// the current contents of the object when deciding how the update object should look.
                            	// If the key doesn't exist, it will return NotFound storage error if ignoreNotFound=false
                            	// or zero value in 'ptrToType' parameter otherwise.
                            	// If the object to update has the same value as previous, it won't do any update
                            	// but will return the object in 'ptrToType' parameter.
                            	// If 'suggestion' can contain zero or one element - in such case this can be used as
                            	// a suggestion about the current version of the object to avoid read operation from
                            	// storage to get it.
                            	//
                            	// Example:
                            	//
                            	// s := /* implementation of Interface */
                            	// err := s.GuaranteedUpdate(
                            	//     "myKey", &MyType{}, true,
                            	//     func(input runtime.Object, res ResponseMeta) (runtime.Object, *uint64, error) {
                            	//       // Before each incovation of the user defined function, "input" is reset to
                            	//       // current contents for "myKey" in database.
                            	//       curr := input.(*MyType)  // Guaranteed to succeed.
                            	//
                            	//       // Make the modification
                            	//       curr.Counter++
                            	//
                            	//       // Return the modified object - return an error to stop iterating. Return
                            	//       // a uint64 to alter the TTL on the object, or nil to keep it the same value.
                            	//       return cur, nil, nil
                            	//    }
                            	// })
                            	GuaranteedUpdate(
                            		ctx context.Context, key string, ptrToType runtime.Object, ignoreNotFound bool,
                            		precondtions *Preconditions, tryUpdate UpdateFunc, suggestion ...runtime.Object) error
                            
                            	// Count returns number of different entries under the key (generally being path prefix).
                            	Count(key string) (int64, error)
                            }

                              Interface offers a common interface for object marshaling/unmarshaling operations and hides all the storage-related operations behind it.

                              type InternalError

                              type InternalError struct {
                              	Reason string
                              }

                                InternalError is generated when an error occurs in the storage package, i.e., not from the underlying storage backend (e.g., etcd).

                                func NewInternalError

                                func NewInternalError(reason string) InternalError

                                func NewInternalErrorf

                                func NewInternalErrorf(format string, a ...interface{}) InternalError

                                func (InternalError) Error

                                func (e InternalError) Error() string

                                type InvalidError

                                type InvalidError struct {
                                	Errs field.ErrorList
                                }

                                  InvalidError is generated when an error caused by invalid API object occurs in the storage package.

                                  func NewInvalidError

                                  func NewInvalidError(errors field.ErrorList) InvalidError

                                  func (InvalidError) Error

                                  func (e InvalidError) Error() string

                                  type MatchValue

                                  type MatchValue struct {
                                  	IndexName string
                                  	Value     string
                                  }

                                    MatchValue defines a pair (<index name>, <value for that index>).

                                    func NoTriggerFunc

                                    func NoTriggerFunc() []MatchValue

                                    func NoTriggerPublisher

                                    func NoTriggerPublisher(runtime.Object) []MatchValue

                                    type Preconditions

                                    type Preconditions struct {
                                    	// Specifies the target UID.
                                    	// +optional
                                    	UID *types.UID `json:"uid,omitempty"`
                                    	// Specifies the target ResourceVersion
                                    	// +optional
                                    	ResourceVersion *string `json:"resourceVersion,omitempty"`
                                    }

                                      Preconditions must be fulfilled before an operation (update, delete, etc.) is carried out.

                                      func NewUIDPreconditions

                                      func NewUIDPreconditions(uid string) *Preconditions

                                        NewUIDPreconditions returns a Preconditions with UID set.

                                        func (*Preconditions) Check

                                        func (p *Preconditions) Check(key string, obj runtime.Object) error

                                        type ResponseMeta

                                        type ResponseMeta struct {
                                        	// TTL is the time to live of the node that contained the returned object. It may be
                                        	// zero or negative in some cases (objects may be expired after the requested
                                        	// expiration time due to server lag).
                                        	TTL int64
                                        	// The resource version of the node that contained the returned object.
                                        	ResourceVersion uint64
                                        }

                                          ResponseMeta contains information about the database metadata that is associated with an object. It abstracts the actual underlying objects to prevent coupling with concrete database and to improve testability.

                                          type SelectionPredicate

                                          type SelectionPredicate struct {
                                          	Label       labels.Selector
                                          	Field       fields.Selector
                                          	GetAttrs    AttrFunc
                                          	IndexFields []string
                                          	Limit       int64
                                          	Continue    string
                                          }

                                            SelectionPredicate is used to represent the way to select objects from api storage.

                                            func (*SelectionPredicate) Empty

                                            func (s *SelectionPredicate) Empty() bool

                                              Empty returns true if the predicate performs no filtering.

                                              func (*SelectionPredicate) MatcherIndex

                                              func (s *SelectionPredicate) MatcherIndex() []MatchValue

                                                For any index defined by IndexFields, if a matcher can match only (a subset) of objects that return <value> for a given index, a pair (<index name>, <value>) wil be returned. TODO: Consider supporting also labels.

                                                func (*SelectionPredicate) Matches

                                                func (s *SelectionPredicate) Matches(obj runtime.Object) (bool, error)

                                                  Matches returns true if the given object's labels and fields (as returned by s.GetAttrs) match s.Label and s.Field. An error is returned if s.GetAttrs fails.

                                                  func (*SelectionPredicate) MatchesObjectAttributes

                                                  func (s *SelectionPredicate) MatchesObjectAttributes(l labels.Set, f fields.Set) bool

                                                    MatchesObjectAttributes returns true if the given labels and fields match s.Label and s.Field.

                                                    func (*SelectionPredicate) MatchesSingle

                                                    func (s *SelectionPredicate) MatchesSingle() (string, bool)

                                                      MatchesSingle will return (name, true) if and only if s.Field matches on the object's name.

                                                      type SimpleUpdateFunc

                                                      type SimpleUpdateFunc func(runtime.Object) (runtime.Object, error)

                                                      type StorageError

                                                      type StorageError struct {
                                                      	Code               int
                                                      	Key                string
                                                      	ResourceVersion    int64
                                                      	AdditionalErrorMsg string
                                                      }

                                                      func NewInvalidObjError

                                                      func NewInvalidObjError(key, msg string) *StorageError

                                                      func NewKeyExistsError

                                                      func NewKeyExistsError(key string, rv int64) *StorageError

                                                      func NewKeyNotFoundError

                                                      func NewKeyNotFoundError(key string, rv int64) *StorageError

                                                      func NewResourceVersionConflictsError

                                                      func NewResourceVersionConflictsError(key string, rv int64) *StorageError

                                                      func NewUnreachableError

                                                      func NewUnreachableError(key string, rv int64) *StorageError

                                                      func (*StorageError) Error

                                                      func (e *StorageError) Error() string

                                                      type TriggerPublisherFunc

                                                      type TriggerPublisherFunc func(obj runtime.Object) []MatchValue

                                                        TriggerPublisherFunc is a function that takes an object, and returns a list of pairs (<index name>, <index value for the given object>) for all indexes known to that function.

                                                        type UpdateFunc

                                                        type UpdateFunc func(input runtime.Object, res ResponseMeta) (output runtime.Object, ttl *uint64, err error)

                                                          Pass an UpdateFunc to Interface.GuaranteedUpdate to make an update that is guaranteed to succeed. See the comment for GuaranteedUpdate for more details.

                                                          func SimpleUpdate

                                                          func SimpleUpdate(fn SimpleUpdateFunc) UpdateFunc

                                                            SimpleUpdateFunc converts SimpleUpdateFunc into UpdateFunc

                                                            type Versioner

                                                            type Versioner interface {
                                                            	// UpdateObject sets storage metadata into an API object. Returns an error if the object
                                                            	// cannot be updated correctly. May return nil if the requested object does not need metadata
                                                            	// from database.
                                                            	UpdateObject(obj runtime.Object, resourceVersion uint64) error
                                                            	// UpdateList sets the resource version into an API list object. Returns an error if the object
                                                            	// cannot be updated correctly. May return nil if the requested object does not need metadata
                                                            	// from database. continueValue is optional and indicates that more results are available if
                                                            	// the client passes that value to the server in a subsequent call.
                                                            	UpdateList(obj runtime.Object, resourceVersion uint64, continueValue string) error
                                                            	// PrepareObjectForStorage should set SelfLink and ResourceVersion to the empty value. Should
                                                            	// return an error if the specified object cannot be updated.
                                                            	PrepareObjectForStorage(obj runtime.Object) error
                                                            	// ObjectResourceVersion returns the resource version (for persistence) of the specified object.
                                                            	// Should return an error if the specified object does not have a persistable version.
                                                            	ObjectResourceVersion(obj runtime.Object) (uint64, error)
                                                            
                                                            	// ParseResourceVersion takes a resource version argument and
                                                            	// converts it to the storage backend. For watch we should pass to helper.Watch().
                                                            	// Because resourceVersion is an opaque value, the default watch
                                                            	// behavior for non-zero watch is to watch the next value (if you pass
                                                            	// "1", you will see updates from "2" onwards).
                                                            	ParseResourceVersion(resourceVersion string) (uint64, error)
                                                            }

                                                              Versioner abstracts setting and retrieving metadata fields from database response onto the object ot list. It is required to maintain storage invariants - updating an object twice with the same data except for the ResourceVersion and SelfLink must be a no-op. A resourceVersion of type uint64 is a 'raw' resourceVersion, intended to be sent directly to or from the backend. A resourceVersion of type string is a 'safe' resourceVersion, intended for consumption by users.

                                                              Directories

                                                              Path Synopsis
                                                              Package storage provides conversion of storage errors to API errors.
                                                              Package storage provides conversion of storage errors to API errors.
                                                              util
                                                              Package util holds generic etcd-related utility functions that any user of ectd might want to use, without pulling in kubernetes-specific code.
                                                              Package util holds generic etcd-related utility functions that any user of ectd might want to use, without pulling in kubernetes-specific code.
                                                              Package value contains methods for assisting with transformation of values in storage.
                                                              Package value contains methods for assisting with transformation of values in storage.
                                                              encrypt/aes
                                                              Package aes transforms values for storage at rest using AES-GCM.
                                                              Package aes transforms values for storage at rest using AES-GCM.
                                                              encrypt/envelope
                                                              Package envelope transforms values for storage at rest using a Envelope provider Package envelope transforms values for storage at rest using a Envelope provider
                                                              Package envelope transforms values for storage at rest using a Envelope provider Package envelope transforms values for storage at rest using a Envelope provider
                                                              encrypt/envelope/v1beta1
                                                              Package v1beta1 is a generated protocol buffer package.
                                                              Package v1beta1 is a generated protocol buffer package.
                                                              encrypt/secretbox
                                                              Package secretbox transforms values for storage at rest using XSalsa20 and Poly1305.
                                                              Package secretbox transforms values for storage at rest using XSalsa20 and Poly1305.