Package com.inductiveautomation.historian.gateway.api.query

Class AbstractQueryEngine

java.lang.Object

com.inductiveautomation.historian.gateway.api.query.AbstractQueryEngine

All Implemented Interfaces:

QueryEngine

public abstract class AbstractQueryEngine
extends Object
implements QueryEngine

Abstract base class for building query engines that support various types of querying (raw, aggregated, and complex) over historical data. This class implements the QueryEngine interface and provides foundational behavior for managing query operations, logging, error handling, and performance metrics.

Concrete subclasses should implement specific query behaviors by overriding the provided protected methods for handling raw data, aggregated data, and complex query types.

This class is initialized with a gateway context, historian name, logging utilities, a path adapter, and supported complex point types. It also relies on a metrics object for tracking performance during query execution.

Thread-safe methods are provided for browsing and querying using various input parameters and result processors, while enforcing validation rules and quality codes for unsupported or unavailable operations.

Field Summary

Fields

Modifier and Type	Field	Description
protected final GatewayContext	gatewayContext
protected final String	historianName
protected final LoggerEx	logger
protected final QueryMetrics	metrics
protected final QualifiedPathAdapter	pathAdapter
protected final Set<? extends ComplexPointType>	supportedComplexTypes

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractQueryEngine(GatewayContext gatewayContext, String historianName, LoggerEx logger)
protected	AbstractQueryEngine(GatewayContext gatewayContext, String historianName, LoggerEx logger, QualifiedPathAdapter pathAdapter)
protected	AbstractQueryEngine(GatewayContext gatewayContext, String historianName, LoggerEx logger, QualifiedPathAdapter pathAdapter, Set<? extends ComplexPointType> supportedComplexTypes)

Method Summary

Modifier and Type	Method	Description
final void	browse(QualifiedPath root, BrowseFilter filter, BrowsePublisher results)	Allows browsing of a tree structure starting at a given root path while applying a filter and passing the results to a specified publisher.
protected abstract void	doBrowse(QualifiedPath root, BrowseFilter filter, BrowsePublisher results)
protected Optional<Integer>	doQueryAggregated(AggregatedQueryOptions options, AggregatedPointProcessor processor)
protected Optional<Integer>	doQueryAnnotations(AnnotationQueryOptions options, AnnotationPointProcessor processor)
protected final <P extends ComplexPoint<?>, K extends ComplexQueryKey<?>> Optional<Integer>	doQueryComplex(ComplexQueryOptions<K> options, ComplexPointProcessor<P,K> processor)
protected Optional<Integer>	doQueryMetadata(MetadataQueryOptions options, MetadataPointProcessor processor)
protected abstract Optional<Integer>	doQueryRaw(RawQueryOptions options, RawPointProcessor processor)
protected boolean	isAggregationTypeSupported(AggregationType type)
protected boolean	isComplexTypeSupported(ComplexQueryOptions<?> options)
protected abstract boolean	isEngineUnavailable()
protected abstract Optional<? extends HistoricalNode>	lookupNode(QualifiedPath source)
protected <P extends TemporalPoint<?, T>, K extends QueryKey<T>, T extends TemporalPointType & QueryablePointType<T>> Map<K,? extends HistoricalNode>	mapKeysToNodes(QueryOptions<K,T> options, QueriedPointProcessor<P,K,T> processor, Function<K,QualifiedPath> sourceGetter)	Maps query keys to historical nodes, querying for missing nodes as needed.
protected QualifiedPath	normalizePath(QualifiedPath path)
final void	query(AggregatedQueryOptions options, AggregatedPointProcessor processor)	Executes an aggregated query based on the provided options and processes the results using the specified processor.
final <P extends ComplexPoint<?>, K extends ComplexQueryKey<?>> void	query(ComplexQueryOptions<K> options, ComplexPointProcessor<P,K> processor)	Executes a query on complex points based on the provided options and processes the results using the specified processor.
final void	query(RawQueryOptions options, RawPointProcessor processor)	Executes a query to retrieve raw data points based on the provided options and processes the results using the specified processor.
protected abstract Map<QualifiedPath,? extends HistoricalNode>	queryForHistoricalNodes(Set<QualifiedPath> sources, @Nullable TimeRange timeRange)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.inductiveautomation.historian.gateway.api.query.QueryEngine

getNativeAggregates

Field Details

logger

protected final LoggerEx logger

gatewayContext

protected final GatewayContext gatewayContext

historianName

protected final String historianName

pathAdapter

protected final QualifiedPathAdapter pathAdapter

supportedComplexTypes

protected final Set<? extends ComplexPointType> supportedComplexTypes

metrics

protected final QueryMetrics metrics

Constructor Details

AbstractQueryEngine

protected AbstractQueryEngine(GatewayContext gatewayContext,
 String historianName,
 LoggerEx logger)

AbstractQueryEngine

protected AbstractQueryEngine(GatewayContext gatewayContext,
 String historianName,
 LoggerEx logger,
 QualifiedPathAdapter pathAdapter)

AbstractQueryEngine

protected AbstractQueryEngine(GatewayContext gatewayContext,
 String historianName,
 LoggerEx logger,
 QualifiedPathAdapter pathAdapter,
 Set<? extends ComplexPointType> supportedComplexTypes)

Method Details

browse

public final void browse(QualifiedPath root,
 BrowseFilter filter,
 BrowsePublisher results)

Description copied from interface: QueryEngine

Allows browsing of a tree structure starting at a given root path while applying a filter and passing the results to a specified publisher.

Specified by:

browse in interface QueryEngine

Parameters:

root - the starting path for the browse operation

filter - defines the criteria for filtering browse results

results - publishes the results of the browse operation

query

public final void query(RawQueryOptions options,
 RawPointProcessor processor)

Description copied from interface: QueryEngine

Executes a query to retrieve raw data points based on the provided options and processes the results using the specified processor.

Specified by:

query in interface QueryEngine

Parameters:

options - the configuration for the raw data query, including parameters such as time range, paths, and other query-specific settings

processor - the handler responsible for processing the retrieved raw data points

query

public final void query(AggregatedQueryOptions options,
 AggregatedPointProcessor processor)

Description copied from interface: QueryEngine

Executes an aggregated query based on the provided options and processes the results using the specified processor. This method defaults to indicate that aggregated queries aren't supported.

Specified by:

query in interface QueryEngine

Parameters:

options - the configuration for the aggregated query, including time window settings, paths, and other query parameters

processor - the handler responsible for processing the retrieved aggregated data points

query

public final <P extends ComplexPoint<?>,
K extends ComplexQueryKey<?>>
void query(ComplexQueryOptions<K> options,
 ComplexPointProcessor<P,K> processor)

Description copied from interface: QueryEngine

Executes a query on complex points based on the provided options and processes the results using the specified processor. This default implementation indicates that complex queries aren't supported.

Specified by:

query in interface QueryEngine

Type Parameters:

P - the type of complex point being processed

K - the type of complex query key

Parameters:

options - the configuration for the complex query, including query-specific settings

processor - the handler responsible for processing the complex query results

doQueryComplex

protected final <P extends ComplexPoint<?>,
K extends ComplexQueryKey<?>>
Optional<Integer> doQueryComplex(ComplexQueryOptions<K> options,
 ComplexPointProcessor<P,K> processor)

doQueryAnnotations

protected Optional<Integer> doQueryAnnotations(AnnotationQueryOptions options,
 AnnotationPointProcessor processor)

doQueryMetadata

protected Optional<Integer> doQueryMetadata(MetadataQueryOptions options,
 MetadataPointProcessor processor)

doQueryAggregated

protected Optional<Integer> doQueryAggregated(AggregatedQueryOptions options,
 AggregatedPointProcessor processor)

mapKeysToNodes

protected <P extends TemporalPoint<?,
T>,
K extends QueryKey<T>,
T extends TemporalPointType & QueryablePointType<T>>
Map<K,? extends HistoricalNode> mapKeysToNodes(QueryOptions<K,T> options,
 QueriedPointProcessor<P,K,T> processor,
 Function<K,QualifiedPath> sourceGetter)

Maps query keys to historical nodes, querying for missing nodes as needed.

Type Parameters:

P - type of temporal point

K - type of query key

T - type of temporal point type

Parameters:

options - the query options containing keys to map

processor - the processor to handle failures

sourceGetter - function to extract source path from query key

Returns:

map of query keys to their corresponding historical nodes

normalizePath

protected QualifiedPath normalizePath(QualifiedPath path)

isAggregationTypeSupported

protected boolean isAggregationTypeSupported(AggregationType type)

isComplexTypeSupported

protected boolean isComplexTypeSupported(ComplexQueryOptions<?> options)

lookupNode

protected abstract Optional<? extends HistoricalNode> lookupNode(QualifiedPath source)

queryForHistoricalNodes

protected abstract Map<QualifiedPath,? extends HistoricalNode> queryForHistoricalNodes(Set<QualifiedPath> sources,
 @Nullable
 @Nullable TimeRange timeRange)

doQueryRaw

protected abstract Optional<Integer> doQueryRaw(RawQueryOptions options,
 RawPointProcessor processor)

isEngineUnavailable

protected abstract boolean isEngineUnavailable()

doBrowse

protected abstract void doBrowse(QualifiedPath root,
 BrowseFilter filter,
 BrowsePublisher results)