UTF-8 support in metric and label names

prometheus-metrics-config/src/main/java/io/prometheus/metrics/config/NamingProperties.java

@@ -0,0 +1,43 @@
+package io.prometheus.metrics.config;
+
+import java.util.Map;
+
+public class NamingProperties {
+
+  private static final String VALIDATION_SCHEME = "validationScheme";
+  private final String validationScheme;
+
+  private NamingProperties(String validation) {
+    this.validationScheme = validation;
+  }
+
+  public String getValidationScheme() {
+    return validationScheme;
+  }
+
+  static NamingProperties load(String prefix, Map<Object, Object> properties) throws PrometheusPropertiesException {
+    String validationScheme = Util.loadString(prefix + "." + VALIDATION_SCHEME, properties);
+    return new NamingProperties(validationScheme);
+  }
+
+  public static Builder builder() {
+    return new Builder();
+  }
+
+  public static class Builder {
+
+    private String validationScheme;
+
+    private Builder() {}
+
+    public Builder validation(String validationScheme) {
+      this.validationScheme = validationScheme;
+      return this;
+    }
+
+    public NamingProperties build() {
+      return new NamingProperties(validationScheme);
+    }
+  }
+
+}

prometheus-metrics-config/src/main/java/io/prometheus/metrics/config/PrometheusProperties.java

@@ -20,6 +20,7 @@ public class PrometheusProperties {
   private final ExporterHttpServerProperties exporterHttpServerProperties;
   private final ExporterOpenTelemetryProperties exporterOpenTelemetryProperties;
   private final ExporterPushgatewayProperties exporterPushgatewayProperties;
+  private final NamingProperties namingProperties;
 
   /**
    * Get the properties instance. When called for the first time, {@code get()} loads the properties
@@ -44,7 +45,8 @@ public PrometheusProperties(
       ExporterFilterProperties exporterFilterProperties,
       ExporterHttpServerProperties httpServerConfig,
       ExporterPushgatewayProperties pushgatewayProperties,
-      ExporterOpenTelemetryProperties otelConfig) {
+      ExporterOpenTelemetryProperties otelConfig,
+      NamingProperties namingProperties) {
     this.defaultMetricsProperties = defaultMetricsProperties;
     this.metricProperties.putAll(metricProperties);
     this.exemplarProperties = exemplarProperties;
@@ -53,6 +55,7 @@ public PrometheusProperties(
     this.exporterHttpServerProperties = httpServerConfig;
     this.exporterPushgatewayProperties = pushgatewayProperties;
     this.exporterOpenTelemetryProperties = otelConfig;
+    this.namingProperties = namingProperties;
   }
 
   /**
@@ -95,4 +98,8 @@ public ExporterPushgatewayProperties getExporterPushgatewayProperties() {
   public ExporterOpenTelemetryProperties getExporterOpenTelemetryProperties() {
     return exporterOpenTelemetryProperties;
   }
+
+  public NamingProperties getNamingProperties() {
+    return namingProperties;
+  }
 }

prometheus-metrics-config/src/main/java/io/prometheus/metrics/config/PrometheusPropertiesLoader.java

@@ -4,6 +4,7 @@
 import java.io.InputStream;
 import java.nio.file.Files;
 import java.nio.file.Paths;
+import java.rmi.Naming;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
@@ -42,6 +43,7 @@ public static PrometheusProperties load(Map<Object, Object> externalProperties)
         ExporterPushgatewayProperties.load(properties);
     ExporterOpenTelemetryProperties exporterOpenTelemetryProperties =
         ExporterOpenTelemetryProperties.load(properties);
+    NamingProperties namingProperties = NamingProperties.load("io.prometheus.naming", properties);
     validateAllPropertiesProcessed(properties);
     return new PrometheusProperties(
         defaultMetricsProperties,
@@ -51,7 +53,8 @@ public static PrometheusProperties load(Map<Object, Object> externalProperties)
         exporterFilterProperties,
         exporterHttpServerProperties,
         exporterPushgatewayProperties,
-        exporterOpenTelemetryProperties);
+        exporterOpenTelemetryProperties,
+        namingProperties);
   }
 
   // This will remove entries from properties when they are processed.

prometheus-metrics-core/src/test/java/io/prometheus/metrics/core/metrics/HistogramTest.java

@@ -1,6 +1,7 @@
 package io.prometheus.metrics.core.metrics;
 
 import static io.prometheus.metrics.core.metrics.TestUtil.assertExemplarEquals;
+import static io.prometheus.metrics.model.snapshots.PrometheusNaming.nameEscapingScheme;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.data.Offset.offset;
@@ -11,12 +12,7 @@
 import io.prometheus.metrics.expositionformats.generated.com_google_protobuf_4_29_3.Metrics;
 import io.prometheus.metrics.expositionformats.internal.PrometheusProtobufWriterImpl;
 import io.prometheus.metrics.expositionformats.internal.ProtobufUtil;
-import io.prometheus.metrics.model.snapshots.ClassicHistogramBucket;
-import io.prometheus.metrics.model.snapshots.Exemplar;
-import io.prometheus.metrics.model.snapshots.Exemplars;
-import io.prometheus.metrics.model.snapshots.HistogramSnapshot;
-import io.prometheus.metrics.model.snapshots.Labels;
-import io.prometheus.metrics.model.snapshots.MetricSnapshots;
+import io.prometheus.metrics.model.snapshots.*;
 import io.prometheus.metrics.tracer.common.SpanContext;
 import io.prometheus.metrics.tracer.initializer.SpanContextSupplier;
 import java.io.ByteArrayOutputStream;
@@ -946,6 +942,7 @@ public void testDefaults() throws IOException {
     // text
     ByteArrayOutputStream out = new ByteArrayOutputStream();
     OpenMetricsTextFormatWriter writer = new OpenMetricsTextFormatWriter(false, true);
+    nameEscapingScheme = EscapingScheme.NO_ESCAPING;
     writer.write(out, MetricSnapshots.of(snapshot));
     assertThat(out).hasToString(expectedTextFormat);
   }

prometheus-metrics-core/src/test/java/io/prometheus/metrics/core/metrics/InfoTest.java

@@ -1,12 +1,14 @@
 package io.prometheus.metrics.core.metrics;
 
+import static io.prometheus.metrics.model.snapshots.PrometheusNaming.nameEscapingScheme;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 import io.prometheus.metrics.expositionformats.OpenMetricsTextFormatWriter;
 import io.prometheus.metrics.expositionformats.generated.com_google_protobuf_4_29_3.Metrics;
 import io.prometheus.metrics.expositionformats.internal.PrometheusProtobufWriterImpl;
 import io.prometheus.metrics.expositionformats.internal.ProtobufUtil;
+import io.prometheus.metrics.model.snapshots.EscapingScheme;
 import io.prometheus.metrics.model.snapshots.Labels;
 import io.prometheus.metrics.model.snapshots.MetricSnapshots;
 import io.prometheus.metrics.model.snapshots.Unit;
@@ -121,6 +123,7 @@ public void testConstLabelsDuplicate2() {
   private void assertTextFormat(String expected, Info info) throws IOException {
     OpenMetricsTextFormatWriter writer = new OpenMetricsTextFormatWriter(true, true);
     ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+    nameEscapingScheme = EscapingScheme.NO_ESCAPING;
     writer.write(outputStream, MetricSnapshots.of(info.collect()));
     String result = outputStream.toString(StandardCharsets.UTF_8.name());
     if (!result.contains(expected)) {

prometheus-metrics-exporter-common/src/main/java/io/prometheus/metrics/exporter/common/PrometheusScrapeHandler.java

@@ -6,6 +6,7 @@
 import io.prometheus.metrics.expositionformats.ExpositionFormats;
 import io.prometheus.metrics.model.registry.MetricNameFilter;
 import io.prometheus.metrics.model.registry.PrometheusRegistry;
+import io.prometheus.metrics.model.snapshots.EscapingScheme;
 import io.prometheus.metrics.model.snapshots.MetricSnapshots;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -19,6 +20,8 @@
 import java.util.function.Predicate;
 import java.util.zip.GZIPOutputStream;
 
+import static io.prometheus.metrics.model.snapshots.PrometheusNaming.nameEscapingScheme;
+
 /** Prometheus scrape endpoint. */
 public class PrometheusScrapeHandler {
 
@@ -54,12 +57,13 @@ public void handleRequest(PrometheusHttpExchange exchange) throws IOException {
     try {
       PrometheusHttpRequest request = exchange.getRequest();
       MetricSnapshots snapshots = scrape(request);
+      String acceptHeader = request.getHeader("Accept");
+      nameEscapingScheme = EscapingScheme.fromAcceptHeader(acceptHeader);
       if (writeDebugResponse(snapshots, exchange)) {
         return;
       }
       ByteArrayOutputStream responseBuffer =
           new ByteArrayOutputStream(lastResponseSize.get() + 1024);
-      String acceptHeader = request.getHeader("Accept");
       ExpositionFormatWriter writer = expositionFormats.findWriter(acceptHeader);
       writer.write(responseBuffer, snapshots);
       lastResponseSize.set(responseBuffer.size());

prometheus-metrics-exporter-pushgateway/src/main/java/io/prometheus/metrics/exporter/pushgateway/PushGateway.java

@@ -1,6 +1,7 @@
 package io.prometheus.metrics.exporter.pushgateway;
 
 import static io.prometheus.metrics.exporter.pushgateway.Scheme.HTTP;
+import static io.prometheus.metrics.model.snapshots.PrometheusNaming.*;
 
 import io.prometheus.metrics.config.ExporterPushgatewayProperties;
 import io.prometheus.metrics.config.PrometheusProperties;
@@ -11,6 +12,8 @@
 import io.prometheus.metrics.model.registry.Collector;
 import io.prometheus.metrics.model.registry.MultiCollector;
 import io.prometheus.metrics.model.registry.PrometheusRegistry;
+import io.prometheus.metrics.model.snapshots.EscapingScheme;
+
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
@@ -200,6 +203,7 @@ private void doRequest(PrometheusRegistry registry, String method) throws IOExce
       try {
         if (!method.equals("DELETE")) {
           OutputStream outputStream = connection.getOutputStream();
+          nameEscapingScheme = EscapingScheme.NO_ESCAPING;
           writer.write(outputStream, registry.scrape());
           outputStream.flush();
           outputStream.close();
@@ -430,11 +434,11 @@ private URL makeUrl(ExporterPushgatewayProperties properties)
       if (groupingKey != null) {
         for (Map.Entry<String, String> entry : groupingKey.entrySet()) {
           if (entry.getValue().isEmpty()) {
-            url += "/" + entry.getKey() + "@base64/=";
+            url += "/" + escapeName(entry.getKey(), EscapingScheme.VALUE_ENCODING_ESCAPING) + "@base64/=";
           } else if (entry.getValue().contains("/")) {
-            url += "/" + entry.getKey() + "@base64/" + base64url(entry.getValue());
+            url += "/" + escapeName(entry.getKey(), EscapingScheme.VALUE_ENCODING_ESCAPING) + "@base64/" + base64url(entry.getValue());
           } else {
-            url += "/" + entry.getKey() + "/" + URLEncoder.encode(entry.getValue(), "UTF-8");
+            url += "/" + escapeName(entry.getKey(), EscapingScheme.VALUE_ENCODING_ESCAPING) + "/" + URLEncoder.encode(entry.getValue(), "UTF-8");
           }
         }
       }