Package org.apache.solr.response

Class PrometheusResponseWriter

java.lang.Object

org.apache.solr.response.PrometheusResponseWriter

All Implemented Interfaces:

QueryResponseWriter, NamedListInitializedPlugin

public class PrometheusResponseWriter
extends Object
implements QueryResponseWriter

Response writer for Prometheus metrics. This is used only by the MetricsHandler and V2 API implementation GetMetrics

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CONTENT_TYPE_OPEN_METRICS
static final String	CONTENT_TYPE_PROMETHEUS

Fields inherited from interface org.apache.solr.response.QueryResponseWriter

CONTENT_TYPE_TEXT_UTF8, CONTENT_TYPE_XML_UTF8

Constructor Summary

Constructors

Constructor	Description
PrometheusResponseWriter()

Method Summary

Modifier and Type	Method	Description
String	getContentType(SolrQueryRequest request, SolrQueryResponse response)	Return the applicable Content Type for a request, this method must be thread safe.
void	write(OutputStream out, SolrQueryRequest request, SolrQueryResponse response, String contentType)	Writes the response to the OutputStream.
void	writeMetricSnapshots(OutputStream out, SolrQueryRequest request, io.prometheus.metrics.model.snapshots.MetricSnapshots snapshots)	Write MetricSnapshots in Prometheus or OpenMetrics format

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.solr.util.plugin.NamedListInitializedPlugin

init

Methods inherited from interface org.apache.solr.response.QueryResponseWriter

write, writeToString

Field Details

CONTENT_TYPE_PROMETHEUS

public static final String CONTENT_TYPE_PROMETHEUS

See Also:

• Constant Field Values

CONTENT_TYPE_OPEN_METRICS

public static final String CONTENT_TYPE_OPEN_METRICS

See Also:

• Constant Field Values

Constructor Details

PrometheusResponseWriter

public PrometheusResponseWriter()

Method Details

write

public void write(OutputStream out,
 SolrQueryRequest request,
 SolrQueryResponse response,
 String contentType)
           throws IOException

Description copied from interface: QueryResponseWriter

Writes the response to the OutputStream. contentType is from QueryResponseWriter.getContentType(SolrQueryRequest, SolrQueryResponse), and it's often ignored.

Specified by:

write in interface QueryResponseWriter

Throws:

IOException

writeMetricSnapshots

public void writeMetricSnapshots(OutputStream out,
 SolrQueryRequest request,
 io.prometheus.metrics.model.snapshots.MetricSnapshots snapshots)
                          throws IOException

Write MetricSnapshots in Prometheus or OpenMetrics format

Throws:

IOException

getContentType

public String getContentType(SolrQueryRequest request,
 SolrQueryResponse response)

Description copied from interface: QueryResponseWriter

Return the applicable Content Type for a request, this method must be thread safe.

QueryResponseWriter's must implement this method to return a valid HTTP Content-Type header for the request, that will logically correspond with the output produced by the write method.

Specified by:

getContentType in interface QueryResponseWriter

Returns:

a Content-Type string, which may not be null.