Package org.apache.pulsar.metadata.api

Interface MetadataStore

All Superinterfaces:

java.lang.AutoCloseable

All Known Subinterfaces:

MetadataStoreExtended

All Known Implementing Classes:

AbstractBatchedMetadataStore, AbstractMetadataStore, EtcdMetadataStore, FaultInjectionMetadataStore, LocalMemoryMetadataStore, RocksdbMetadataStore, ZKMetadataStore

@Beta
public interface MetadataStore
extends java.lang.AutoCloseable

Metadata store client interface. NOTE: This API is still evolving and will be refactored as needed until all the metadata usages are converted into using it.

Method Summary

Modifier and Type	Method	Description
java.util.concurrent.CompletableFuture<java.lang.Void>	delete(java.lang.String path, java.util.Optional<java.lang.Long> expectedVersion)
java.util.concurrent.CompletableFuture<java.lang.Void>	deleteRecursive(java.lang.String path)	Delete a key-value pair and all the children nodes.
java.util.concurrent.CompletableFuture<java.lang.Boolean>	exists(java.lang.String path)	Read whether a specific path exists.
java.util.concurrent.CompletableFuture<java.util.Optional<GetResult>>	get(java.lang.String path)	Read the value of one key, identified by the path The async call will return a future that yields a GetResult that will contain the value and the associated Stat object.
java.util.concurrent.CompletableFuture<java.util.List<java.lang.String>>	getChildren(java.lang.String path)	Return all the nodes (lexicographically sorted) that are children to the specific path.
default MetadataCacheConfig	getDefaultMetadataCacheConfig()	Returns the default metadata cache config.
default <T> MetadataCache<T>	getMetadataCache(com.fasterxml.jackson.core.type.TypeReference<T> typeRef)	Create a metadata cache specialized for a specific class.
<T> MetadataCache<T>	getMetadataCache(com.fasterxml.jackson.core.type.TypeReference<T> typeRef, MetadataCacheConfig cacheConfig)	Create a metadata cache specialized for a specific class.
default <T> MetadataCache<T>	getMetadataCache(java.lang.Class<T> clazz)	Create a metadata cache specialized for a specific class.
<T> MetadataCache<T>	getMetadataCache(java.lang.Class<T> clazz, MetadataCacheConfig cacheConfig)	Create a metadata cache specialized for a specific class.
default <T> MetadataCache<T>	getMetadataCache(MetadataSerde<T> serde)	Create a metadata cache that uses a particular serde object.
<T> MetadataCache<T>	getMetadataCache(MetadataSerde<T> serde, MetadataCacheConfig cacheConfig)	Create a metadata cache that uses a particular serde object.
java.util.concurrent.CompletableFuture<Stat>	put(java.lang.String path, byte[] value, java.util.Optional<java.lang.Long> expectedVersion)	Put a new value for a given key.
void	registerListener(java.util.function.Consumer<Notification> listener)	Register a listener that will be called on changes in the underlying store.

Methods inherited from interface java.lang.AutoCloseable

close

Method Detail

get

java.util.concurrent.CompletableFuture<java.util.Optional<GetResult>> get(java.lang.String path)

Read the value of one key, identified by the path The async call will return a future that yields a GetResult that will contain the value and the associated Stat object. If the value is not found, the future will yield an empty Optional.

Parameters:

path - the path of the key to get from the store

Returns:

a future to track the async request

getChildren

java.util.concurrent.CompletableFuture<java.util.List<java.lang.String>> getChildren(java.lang.String path)

Return all the nodes (lexicographically sorted) that are children to the specific path. If the path itself does not exist, it will return an empty list.

Parameters:

path - the path of the key to get from the store

Returns:

a future to track the async request

exists

java.util.concurrent.CompletableFuture<java.lang.Boolean> exists(java.lang.String path)

Read whether a specific path exists. Note: In case of keys with multiple levels (eg: '/a/b/c'), checking the existence of a parent (eg. '/a') might not necessarily return true, unless the key had been explicitly created.

Parameters:

path - the path of the key to check on the store

Returns:

a future to track the async request

put

java.util.concurrent.CompletableFuture<Stat> put(java.lang.String path,
                                                 byte[] value,
                                                 java.util.Optional<java.lang.Long> expectedVersion)

Put a new value for a given key. The caller can specify an expected version to be atomically checked against the current version of the stored data. The future will return the Stat object associated with the newly inserted value.

Parameters:

path - the path of the key to delete from the store

value - the value to

expectedVersion - if present, the version will have to match with the currently stored value for the operation to succeed. Use -1 to enforce a non-existing value.

Returns:

a future to track the async request

Throws:

MetadataStoreException.BadVersionException - if the expected version doesn't match the actual version of the data

delete

java.util.concurrent.CompletableFuture<java.lang.Void> delete(java.lang.String path,
                                                              java.util.Optional<java.lang.Long> expectedVersion)

Parameters:

path - the path of the key to delete from the store

expectedVersion - if present, the version will have to match with the currently stored value for the operation to succeed

Returns:

a future to track the async request

Throws:

MetadataStoreException.NotFoundException - if the path is not found

MetadataStoreException.BadVersionException - if the expected version doesn't match the actual version of the data

deleteRecursive

java.util.concurrent.CompletableFuture<java.lang.Void> deleteRecursive(java.lang.String path)

Delete a key-value pair and all the children nodes. Note: the operation might not be carried in an atomic fashion. If the operation fails, the deletion of the tree might be only partial.

Parameters:

path - the path of the key to delete from the store

Returns:

a future to track the async request

registerListener

void registerListener(java.util.function.Consumer<Notification> listener)

Register a listener that will be called on changes in the underlying store.

Parameters:

listener - a consumer of notifications

getMetadataCache

<T> MetadataCache<T> getMetadataCache(java.lang.Class<T> clazz,
                                      MetadataCacheConfig cacheConfig)

Create a metadata cache specialized for a specific class.

Type Parameters:

T -

Parameters:

clazz - the class type to be used for serialization/deserialization

cacheConfig - the cache configuration to be used

Returns:

the metadata cache object

getMetadataCache

default <T> MetadataCache<T> getMetadataCache(java.lang.Class<T> clazz)

Create a metadata cache specialized for a specific class.

Type Parameters:

T -

Parameters:

clazz - the class type to be used for serialization/deserialization

Returns:

the metadata cache object

getMetadataCache

<T> MetadataCache<T> getMetadataCache(com.fasterxml.jackson.core.type.TypeReference<T> typeRef,
                                      MetadataCacheConfig cacheConfig)

Create a metadata cache specialized for a specific class.

Type Parameters:

T -

Parameters:

typeRef - the type ref description to be used for serialization/deserialization

cacheConfig - the cache configuration to be used

Returns:

the metadata cache object

getMetadataCache

default <T> MetadataCache<T> getMetadataCache(com.fasterxml.jackson.core.type.TypeReference<T> typeRef)

Create a metadata cache specialized for a specific class.

Type Parameters:

T -

Parameters:

typeRef - the type ref description to be used for serialization/deserialization

Returns:

the metadata cache object

getMetadataCache

<T> MetadataCache<T> getMetadataCache(MetadataSerde<T> serde,
                                      MetadataCacheConfig cacheConfig)

Create a metadata cache that uses a particular serde object.

Type Parameters:

T -

Parameters:

serde - the custom serialization/deserialization object

cacheConfig - the cache configuration to be used

Returns:

the metadata cache object

getMetadataCache

default <T> MetadataCache<T> getMetadataCache(MetadataSerde<T> serde)

Create a metadata cache that uses a particular serde object.

Type Parameters:

T -

Parameters:

serde - the custom serialization/deserialization object

Returns:

the metadata cache object

getDefaultMetadataCacheConfig

default MetadataCacheConfig getDefaultMetadataCacheConfig()

Returns the default metadata cache config.

Returns:

default metadata cache config