Package com.google.datastore.v1.client

Class DatastoreHelper

java.lang.Object
com.google.datastore.v1.client.DatastoreHelper
public final class DatastoreHelper extends Object
Helper methods for Datastore.

  • Field Details

    • SCATTER_PROPERTY_NAME

      public static final String SCATTER_PROPERTY_NAME
      The property used in the Datastore to give us a random distribution. *
      See Also:

    • KEY_PROPERTY_NAME

      public static final String KEY_PROPERTY_NAME
      The property used in the Datastore to get the key of the entity. *
      See Also:

    • PROJECT_ID_ENV_VAR

      public static final String PROJECT_ID_ENV_VAR
      Name of the environment variable used to set the project ID.
      See Also:

    • LOCAL_HOST_ENV_VAR

      public static final String LOCAL_HOST_ENV_VAR
      Name of the environment variable used to set the local host.
      See Also:

    • SERVICE_ACCOUNT_ENV_VAR

      public static final String SERVICE_ACCOUNT_ENV_VAR
      Name of the environment variable used to set the service account.
      See Also:

    • PRIVATE_KEY_FILE_ENV_VAR

      public static final String PRIVATE_KEY_FILE_ENV_VAR
      Name of the environment variable used to set the private key file.
      See Also:

  • Method Details

    • getServiceAccountCredential

      public static com.google.api.client.auth.oauth2.Credential getServiceAccountCredential(String serviceAccountId, String privateKeyFile) throws GeneralSecurityException, IOException
      Constructs credentials for the given account and key.
      Parameters:
      serviceAccountId - service account ID (typically an e-mail address).
      privateKeyFile - the file name from which to get the private key.
      Returns:
      valid credentials or null
      Throws:
      GeneralSecurityException
      IOException

    • getServiceAccountCredential

      public static com.google.api.client.auth.oauth2.Credential getServiceAccountCredential(String serviceAccountId, String privateKeyFile, Collection<String> serviceAccountScopes) throws GeneralSecurityException, IOException
      Constructs credentials for the given account and key file.
      Parameters:
      serviceAccountId - service account ID (typically an e-mail address).
      privateKeyFile - the file name from which to get the private key.
      serviceAccountScopes - Collection of OAuth scopes to use with the the service account flow or null if not.
      Returns:
      valid credentials or null
      Throws:
      GeneralSecurityException
      IOException

    • getServiceAccountCredential

      public static com.google.api.client.auth.oauth2.Credential getServiceAccountCredential(String serviceAccountId, PrivateKey privateKey, Collection<String> serviceAccountScopes) throws GeneralSecurityException, IOException
      Constructs credentials for the given account and key.
      Parameters:
      serviceAccountId - service account ID (typically an e-mail address).
      privateKey - the private key for the given account.
      serviceAccountScopes - Collection of OAuth scopes to use with the the service account flow or null if not.
      Returns:
      valid credentials or null
      Throws:
      GeneralSecurityException
      IOException

    • getOptionsFromEnv

      public static DatastoreOptions.Builder getOptionsFromEnv() throws GeneralSecurityException, IOException
      Constructs a Datastore from environment variables and/or the Compute Engine metadata server.

      The project ID is determined from, in order of preference:

      • DATASTORE_PROJECT_ID environment variable
      • Compute Engine

      Credentials are taken from, in order of preference:

      1. No credentials (if the DATASTORE_EMULATOR_HOST environment variable is set)
      2. Service Account specified by the DATASTORE_SERVICE_ACCOUNT and DATASTORE_PRIVATE_KEY_FILE environment variables
      3. Google Application Default as described here.
      Throws:
      GeneralSecurityException
      IOException

    • getProjectIdFromComputeEngine

      @Nullable public static String getProjectIdFromComputeEngine()
      Gets the project ID from the Compute Engine metadata server. Returns null if the project ID cannot be determined (because, for instance, the code is not running on Compute Engine).

    • getDatastoreFromEnv

      public static Datastore getDatastoreFromEnv() throws GeneralSecurityException, IOException
      Throws:
      GeneralSecurityException
      IOException
      See Also:

    • getQuerySplitter

      public static QuerySplitter getQuerySplitter()
      Gets a QuerySplitter.

      The returned QuerySplitter.getSplits(com.google.datastore.v1.Query, com.google.datastore.v1.PartitionId, int, com.google.datastore.v1.client.Datastore) cannot accept a query that contains inequality filters, a sort filter, or a missing kind.

    • getKeyComparator

      public static Comparator<Key> getKeyComparator()

    • makeOrder

      public static PropertyOrder.Builder makeOrder(String property, PropertyOrder.Direction direction)
      Make a sort order for use in a query.

    • makeAncestorFilter

      public static Filter.Builder makeAncestorFilter(Key ancestor)
      Makes an ancestor filter.

    • makeFilter

      public static Filter.Builder makeFilter(String property, PropertyFilter.Operator operator, Value value)
      Make a filter on a property for use in a query.

    • makeFilter

      public static Filter.Builder makeFilter(String property, PropertyFilter.Operator operator, Value.Builder value)
      Make a filter on a property for use in a query.

    • makeAndFilter

      public static Filter.Builder makeAndFilter(Filter... subfilters)
      Make a composite filter from the given sub-filters using AND to combine filters.

    • makeAndFilter

      public static Filter.Builder makeAndFilter(Iterable<Filter> subfilters)
      Make a composite filter from the given sub-filters using AND to combine filters.

    • makePropertyReference

      public static PropertyReference.Builder makePropertyReference(String propertyName)
      Make a property reference for use in a query.

    • makeValue

      public static Value.Builder makeValue(Iterable<Value> values)
      Make an array value containing the specified values.

    • makeValue

      public static Value.Builder makeValue(Value value1, Value value2, Value... rest)
      Make a list value containing the specified values.

    • makeValue

      public static Value.Builder makeValue(Value.Builder value1, Value.Builder value2, Value.Builder... rest)
      Make an array value containing the specified values.

    • makeValue

      public static Value.Builder makeValue(Key key)
      Make a key value.

    • makeValue

      public static Value.Builder makeValue(Key.Builder key)
      Make a key value.

    • makeValue

      public static Value.Builder makeValue(long key)
      Make an integer value.

    • makeValue

      public static Value.Builder makeValue(double value)
      Make a floating point value.

    • makeValue

      public static Value.Builder makeValue(boolean value)
      Make a boolean value.

    • makeValue

      public static Value.Builder makeValue(String value)
      Make a string value.

    • makeValue

      public static Value.Builder makeValue(Entity entity)
      Make an entity value.

    • makeValue

      public static Value.Builder makeValue(Entity.Builder entity)
      Make a entity value.

    • makeValue

      public static Value.Builder makeValue(com.google.protobuf.ByteString blob)
      Make a ByteString value.

    • makeValue

      public static Value.Builder makeValue(Date date)
      Make a timestamp value given a date.

    • makeValue

      public static Value.Builder makeValue(com.google.type.LatLng value)
      Makes a GeoPoint value.

    • makeValue

      public static Value.Builder makeValue(com.google.type.LatLng.Builder value)
      Makes a GeoPoint value.

    • makeKey

      public static Key.Builder makeKey(Object... elements)
      Make a key from the specified path of kind/id-or-name pairs and/or Keys.

      The id-or-name values must be either String, Long, Integer or Short.

      The last id-or-name value may be omitted, in which case an entity without an id is created (for use with automatic id allocation).

      The PartitionIds of all Keys in the path must be equal. The returned Key.Builder will use this PartitionId.

    • getDouble

      public static double getDouble(Value value)
      Returns:
      the double contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a double.

    • getKey

      public static Key getKey(Value value)
      Returns:
      the key contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a key.

    • getByteString

      public static com.google.protobuf.ByteString getByteString(Value value)
      Returns:
      the blob contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a blob.

    • getEntity

      public static Entity getEntity(Value value)
      Returns:
      the entity contained in value
      Throws:
      IllegalArgumentException - if the value does not contain an entity.

    • getString

      public static String getString(Value value)
      Returns:
      the string contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a string.

    • getBoolean

      public static boolean getBoolean(Value value)
      Returns:
      the boolean contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a boolean.

    • getLong

      public static long getLong(Value value)
      Returns:
      the long contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a long.

    • getTimestamp

      public static long getTimestamp(Value value)
      Returns:
      the timestamp in microseconds contained in value
      Throws:
      IllegalArgumentException - if the value does not contain a timestamp.

    • getList

      public static List<Value> getList(Value value)
      Returns:
      the array contained in value as a list.
      Throws:
      IllegalArgumentException - if the value does not contain an array.

    • toDate

      public static Date toDate(Value value)
      Convert a timestamp value into a Date clipping off the microseconds.
      Parameters:
      value - a timestamp value to convert
      Returns:
      the resulting Date
      Throws:
      IllegalArgumentException - if the value does not contain a timestamp.

    • makeInsert

      public static Mutation.Builder makeInsert(Entity entity)
      Parameters:
      entity - the entity to insert
      Returns:
      a mutation that will insert an entity

    • makeUpdate

      public static Mutation.Builder makeUpdate(Entity entity)
      Parameters:
      entity - the entity to update
      Returns:
      a mutation that will update an entity

    • makeUpsert

      public static Mutation.Builder makeUpsert(Entity entity)
      Parameters:
      entity - the entity to upsert
      Returns:
      a mutation that will upsert an entity

    • makeDelete

      public static Mutation.Builder makeDelete(Key key)
      Parameters:
      key - the key of the entity to delete
      Returns:
      a mutation that will delete an entity