Include config document path in declarative config error messages

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/AttributeListFactory.java

@@ -30,16 +30,24 @@ static AttributeListFactory getInstance() {
   public Attributes create(List<AttributeNameValueModel> model, DeclarativeConfigContext context) {
     AttributesBuilder builder = Attributes.builder();
 
-    for (AttributeNameValueModel nameValueModel : model) {
-      addToBuilder(nameValueModel, builder);
+    for (int i = 0; i < model.size(); i++) {
+      AttributeNameValueModel nameValueModel = model.get(i);
+      context.pushConfigPath("attributes[" + i + "]");
+      try {
+        addToBuilder(nameValueModel, builder, context);
+      } finally {
+        context.popConfigPath();
+      }
     }
 
     return builder.build();
   }
 
   private static void addToBuilder(
-      AttributeNameValueModel nameValueModel, AttributesBuilder builder) {
-    String name = FileConfigUtil.requireNonNull(nameValueModel.getName(), "attribute name");
+      AttributeNameValueModel nameValueModel,
+      AttributesBuilder builder,
+      DeclarativeConfigContext context) {
+    String name = FileConfigUtil.requireNonNull(context, nameValueModel.getName(), "name");
     Object value = nameValueModel.getValue();
     if (value == null) {
       // Per the configuration schema, an entry with a null value is ignored

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/ComposableRuleBasedSamplerFactory.java

@@ -51,68 +51,86 @@ public ComposableSampler create(
 
     List<ExperimentalComposableRuleBasedSamplerRuleModel> rules = model.getRules();
     if (rules != null) {
-      rules.forEach(
-          rule -> {
-            AttributeMatcher valueMatcher = attributeValuesMatcher(rule.getAttributeValues());
-            AttributeMatcher patternMatcher = attributePatternsMatcher(rule.getAttributePatterns());
-            Set<ExperimentalSpanParentModel> matchingParents =
-                rule.getParent() != null && !rule.getParent().isEmpty()
-                    ? new HashSet<>(rule.getParent())
-                    : null;
-            Set<SpanKind> matchingSpanKinds =
-                rule.getSpanKinds() != null && !rule.getSpanKinds().isEmpty()
-                    ? rule.getSpanKinds().stream()
-                        .map(DeclarativeConfigSamplingPredicate::toSpanKind)
-                        .collect(toSet())
-                    : null;
-
-            SamplingPredicate predicate =
-                new DeclarativeConfigSamplingPredicate(
-                    valueMatcher, patternMatcher, matchingParents, matchingSpanKinds);
-            ComposableSampler sampler =
-                ComposableSamplerFactory.getInstance()
-                    .create(requireNonNull(rule.getSampler(), "rule sampler"), context);
-            builder.add(predicate, sampler);
-          });
+      for (int i = 0; i < rules.size(); i++) {
+        ExperimentalComposableRuleBasedSamplerRuleModel rule = rules.get(i);
+        context.pushConfigPath("rules[" + i + "]");
+        try {
+          AttributeMatcher valueMatcher =
+              attributeValuesMatcher(rule.getAttributeValues(), context);
+          AttributeMatcher patternMatcher =
+              attributePatternsMatcher(rule.getAttributePatterns(), context);
+          Set<ExperimentalSpanParentModel> matchingParents =
+              rule.getParent() != null && !rule.getParent().isEmpty()
+                  ? new HashSet<>(rule.getParent())
+                  : null;
+          Set<SpanKind> matchingSpanKinds =
+              rule.getSpanKinds() != null && !rule.getSpanKinds().isEmpty()
+                  ? rule.getSpanKinds().stream()
+                      .map(DeclarativeConfigSamplingPredicate::toSpanKind)
+                      .collect(toSet())
+                  : null;
+
+          SamplingPredicate predicate =
+              new DeclarativeConfigSamplingPredicate(
+                  valueMatcher, patternMatcher, matchingParents, matchingSpanKinds);
+          ComposableSampler sampler =
+              ComposableSamplerFactory.getInstance()
+                  .create(requireNonNull(context, rule.getSampler(), "sampler"), context);
+          builder.add(predicate, sampler);
+        } finally {
+          context.popConfigPath();
+        }
+      }
     }
 
     return builder.build();
   }
 
   @Nullable
   private static AttributeMatcher attributeValuesMatcher(
-      @Nullable
-          ExperimentalComposableRuleBasedSamplerRuleAttributeValuesModel attributeValuesModel) {
+      @Nullable ExperimentalComposableRuleBasedSamplerRuleAttributeValuesModel attributeValuesModel,
+      DeclarativeConfigContext context) {
     if (attributeValuesModel == null) {
       return null;
     }
-    List<String> values = attributeValuesModel.getValues();
-    if (values == null || values.isEmpty()) {
-      throw new DeclarativeConfigException(".values is required and must be non-empty");
+    context.pushConfigPath("attribute_values");
+    try {
+      List<String> values = attributeValuesModel.getValues();
+      if (values == null || values.isEmpty()) {
+        throw new DeclarativeConfigException(".values is required and must be non-empty");
+      }
+      return new AttributeMatcher(
+          requireNonNull(context, attributeValuesModel.getKey(), "key"),
+          IncludeExcludePredicate.createExactMatching(values, null));
+    } finally {
+      context.popConfigPath();
     }
-    return new AttributeMatcher(
-        requireNonNull(attributeValuesModel.getKey(), "attribute_values key"),
-        IncludeExcludePredicate.createExactMatching(values, null));
   }
 
   @Nullable
   private static AttributeMatcher attributePatternsMatcher(
       @Nullable
-          ExperimentalComposableRuleBasedSamplerRuleAttributePatternsModel attributePatternsModel) {
+          ExperimentalComposableRuleBasedSamplerRuleAttributePatternsModel attributePatternsModel,
+      DeclarativeConfigContext context) {
     if (attributePatternsModel == null) {
       return null;
     }
-    List<String> included = attributePatternsModel.getIncluded();
-    if (included != null && included.isEmpty()) {
-      throw new DeclarativeConfigException("included must not be empty");
-    }
-    List<String> excluded = attributePatternsModel.getExcluded();
-    if (excluded != null && excluded.isEmpty()) {
-      throw new DeclarativeConfigException("excluded must not be empty");
+    context.pushConfigPath("attribute_patterns");
+    try {
+      List<String> included = attributePatternsModel.getIncluded();
+      if (included != null && included.isEmpty()) {
+        throw new DeclarativeConfigException("included must not be empty");
+      }
+      List<String> excluded = attributePatternsModel.getExcluded();
+      if (excluded != null && excluded.isEmpty()) {
+        throw new DeclarativeConfigException("excluded must not be empty");
+      }
+      return new AttributeMatcher(
+          requireNonNull(context, attributePatternsModel.getKey(), "key"),
+          IncludeExcludePredicate.createPatternMatching(included, excluded));
+    } finally {
+      context.popConfigPath();
     }
-    return new AttributeMatcher(
-        requireNonNull(attributePatternsModel.getKey(), "attribute_patterns key"),
-        IncludeExcludePredicate.createPatternMatching(included, excluded));
   }
 
   // Visible for testing

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/ComposableSamplerFactory.java

@@ -7,6 +7,7 @@
 
 import io.opentelemetry.sdk.autoconfigure.declarativeconfig.model.internal.ExperimentalComposableParentThresholdSamplerModel;
 import io.opentelemetry.sdk.autoconfigure.declarativeconfig.model.internal.ExperimentalComposableProbabilitySamplerModel;
+import io.opentelemetry.sdk.autoconfigure.declarativeconfig.model.internal.ExperimentalComposableRuleBasedSamplerModel;
 import io.opentelemetry.sdk.autoconfigure.declarativeconfig.model.internal.ExperimentalComposableSamplerModel;
 import io.opentelemetry.sdk.extension.incubator.trace.samplers.ComposableSampler;
 
@@ -38,11 +39,17 @@ public ComposableSampler create(
     if (model.getProbability() != null) {
       return createProbabilitySampler(model.getProbability());
     }
-    if (model.getRuleBased() != null) {
-      return ComposableRuleBasedSamplerFactory.getInstance().create(model.getRuleBased(), context);
+    ExperimentalComposableRuleBasedSamplerModel ruleBasedModel = model.getRuleBased();
+    if (ruleBasedModel != null) {
+      return context.withConfigPath(
+          "rule_based",
+          () -> ComposableRuleBasedSamplerFactory.getInstance().create(ruleBasedModel, context));
     }
-    if (model.getParentThreshold() != null) {
-      return createParentThresholdSampler(model.getParentThreshold(), context);
+    ExperimentalComposableParentThresholdSamplerModel parentThresholdModel =
+        model.getParentThreshold();
+    if (parentThresholdModel != null) {
+      return context.withConfigPath(
+          "parent_threshold", () -> createParentThresholdSampler(parentThresholdModel, context));
     }
 
     return context.loadComponent(ComposableSampler.class, samplerKeyValue);
@@ -61,8 +68,7 @@ private static ComposableSampler createParentThresholdSampler(
       ExperimentalComposableParentThresholdSamplerModel parentThresholdModel,
       DeclarativeConfigContext context) {
     ExperimentalComposableSamplerModel rootModel =
-        FileConfigUtil.requireNonNull(
-            parentThresholdModel.getRoot(), "parent threshold sampler root");
+        FileConfigUtil.requireNonNull(context, parentThresholdModel.getRoot(), "root");
     ComposableSampler rootSampler = INSTANCE.create(rootModel, context);
     return ComposableSampler.parentThreshold(rootSampler);
   }

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/DeclarativeConfigContext.java

@@ -15,8 +15,10 @@
 import io.opentelemetry.sdk.autoconfigure.spi.internal.ExtendedDeclarativeConfigProperties;
 import io.opentelemetry.sdk.common.InternalTelemetryVersion;
 import java.io.Closeable;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.Deque;
 import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Locale;
@@ -40,6 +42,7 @@ class DeclarativeConfigContext implements ComponentLoader {
   private final Set<AutoConfigureListener> listeners =
       Collections.newSetFromMap(new IdentityHashMap<>());
   private final List<Closeable> closeables = new ArrayList<>();
+  private final Deque<String> configPath = new ArrayDeque<>();
   @Nullable private volatile MeterProvider meterProvider;
   @Nullable private ConfigProvider configProvider;
   @Nullable private List<ComponentProvider> componentProviders = null;
@@ -83,6 +86,42 @@ DeclarativeConfigurationBuilder getBuilder() {
     return Objects.requireNonNull(builder, "builder has not been set");
   }
 
+  /**
+   * Returns the path of the node in the declarative configuration document which is currently being
+   * interpreted, for example {@code .tracer_provider.processors[0].batch}. Returns the empty string
+   * when the root node is being interpreted.
+   */
+  String getConfigPath() {
+    return configPath.isEmpty() ? "" : "." + String.join(".", configPath);
+  }
+
+  /**
+   * Interpret {@code supplier} as if the currently interpreted node was the child of the current
+   * node identified by {@code pathSegment}, restoring the previous {@linkplain #getConfigPath()
+   * configuration path} afterwards.
+   */
+  <T> T withConfigPath(String pathSegment, Supplier<T> supplier) {
+    configPath.addLast(pathSegment);
+    try {
+      return supplier.get();
+    } finally {
+      configPath.removeLast();
+    }
+  }
+
+  /**
+   * Descend into the child node identified by {@code pathSegment}. Callers must ensure that {@link
+   * #popConfigPath()} is called, typically from a {@code finally} block.
+   */
+  void pushConfigPath(String pathSegment) {
+    configPath.addLast(pathSegment);
+  }
+
+  /** Ascend from the node entered by {@link #pushConfigPath(String)}. */
+  void popConfigPath() {
+    configPath.removeLast();
+  }
+
   /**
    * Overload of {@link #setInternalTelemetry(Consumer, Consumer)} for components which do not
    * support setting {@link InternalTelemetryVersion} because they only support {@link

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/FileConfigUtil.java

@@ -16,13 +16,31 @@ final class FileConfigUtil {
 
   private FileConfigUtil() {}
 
-  static <T> T requireNonNull(@Nullable T object, String description) {
+  /**
+   * Returns {@code object} if it is non-null, otherwise throw a {@link DeclarativeConfigException}
+   * describing the missing {@code description}. The description is prefixed with the {@linkplain
+   * DeclarativeConfigContext#getConfigPath() path} of the node currently being interpreted, so that
+   * the error points to its location in the configuration document.
+   */
+  static <T> T requireNonNull(
+      DeclarativeConfigContext context, @Nullable T object, String description) {
     if (object == null) {
-      throw new DeclarativeConfigException(description + " is required but is null");
+      throw new DeclarativeConfigException(
+          withConfigPath(context, description + " is required but is null"));
     }
     return object;
   }
 
+  /**
+   * Prefix {@code message} with the {@linkplain DeclarativeConfigContext#getConfigPath() path} of
+   * the node currently being interpreted, so that errors point to their location in the
+   * configuration document.
+   */
+  static String withConfigPath(DeclarativeConfigContext context, String message) {
+    String path = context.getConfigPath();
+    return path.isEmpty() ? message : path + " " + message;
+  }
+
   static ConfigKeyValue validateSingleKeyValue(
       DeclarativeConfigContext context, Object model, String resourceName) {
     DeclarativeConfigProperties modelConfigProperties =
@@ -34,7 +52,12 @@ static ConfigKeyValue validateSingleKeyValue(
               ? ""
               : ": " + propertyKeys.stream().collect(joining(",", "[", "]"));
       throw new DeclarativeConfigException(
-          resourceName + " must have exactly one entry but has " + propertyKeys.size() + suffix);
+          withConfigPath(
+              context,
+              resourceName
+                  + " must have exactly one entry but has "
+                  + propertyKeys.size()
+                  + suffix));
     }
     String key = propertyKeys.iterator().next();
     DeclarativeConfigProperties value = modelConfigProperties.getStructured(key);

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/LogRecordProcessorFactory.java

@@ -38,11 +38,14 @@ public LogRecordProcessor create(
     ConfigKeyValue processorKeyValue =
         FileConfigUtil.validateSingleKeyValue(context, model, "log record processor");
 
-    if (model.getBatch() != null) {
-      return createBatchLogRecordProcessor(model.getBatch(), context);
+    BatchLogRecordProcessorModel batch = model.getBatch();
+    if (batch != null) {
+      return context.withConfigPath("batch", () -> createBatchLogRecordProcessor(batch, context));
     }
-    if (model.getSimple() != null) {
-      return createSimpleLogRecordProcessor(model.getSimple(), context);
+    SimpleLogRecordProcessorModel simple = model.getSimple();
+    if (simple != null) {
+      return context.withConfigPath(
+          "simple", () -> createSimpleLogRecordProcessor(simple, context));
     }
     if (LogRecordProcessorModelAccessor.getEventToSpanEventBridge(model) != null) {
       return EventToSpanEventBridge.create();
@@ -54,8 +57,7 @@ public LogRecordProcessor create(
   private static LogRecordProcessor createBatchLogRecordProcessor(
       BatchLogRecordProcessorModel batchModel, DeclarativeConfigContext context) {
     LogRecordExporterModel exporterModel =
-        FileConfigUtil.requireNonNull(
-            batchModel.getExporter(), "batch log record processor exporter");
+        FileConfigUtil.requireNonNull(context, batchModel.getExporter(), "exporter");
 
     LogRecordExporter logRecordExporter =
         LogRecordExporterFactory.getInstance().create(exporterModel, context);
@@ -80,8 +82,7 @@ private static LogRecordProcessor createBatchLogRecordProcessor(
   private static LogRecordProcessor createSimpleLogRecordProcessor(
       SimpleLogRecordProcessorModel simpleModel, DeclarativeConfigContext context) {
     LogRecordExporterModel exporterModel =
-        FileConfigUtil.requireNonNull(
-            simpleModel.getExporter(), "simple log record processor exporter");
+        FileConfigUtil.requireNonNull(context, simpleModel.getExporter(), "exporter");
     LogRecordExporter logRecordExporter =
         LogRecordExporterFactory.getInstance().create(exporterModel, context);
     SimpleLogRecordProcessorBuilder builder = SimpleLogRecordProcessor.builder(logRecordExporter);

sdk-extensions/declarative-config/src/main/java/io/opentelemetry/sdk/autoconfigure/declarativeconfig/LoggerProviderFactory.java

@@ -58,10 +58,13 @@ public SdkLoggerProviderBuilder create(
 
     List<LogRecordProcessorModel> processors = loggerProviderModel.getProcessors();
     if (processors != null) {
-      processors.forEach(
-          processor ->
-              builder.addLogRecordProcessor(
-                  LogRecordProcessorFactory.getInstance().create(processor, context)));
+      for (int i = 0; i < processors.size(); i++) {
+        LogRecordProcessorModel processor = processors.get(i);
+        builder.addLogRecordProcessor(
+            context.withConfigPath(
+                "processors[" + i + "]",
+                () -> LogRecordProcessorFactory.getInstance().create(processor, context)));
+      }
     }
 
     ExperimentalLoggerConfiguratorModel loggerConfiguratorModel =
@@ -76,9 +79,13 @@ public SdkLoggerProviderBuilder create(
       List<ExperimentalLoggerMatcherAndConfigModel> loggerMatcherAndConfigs =
           loggerConfiguratorModel.getLoggers();
       if (loggerMatcherAndConfigs != null) {
-        for (ExperimentalLoggerMatcherAndConfigModel loggerMatcherAndConfig :
-            loggerMatcherAndConfigs) {
-          String name = requireNonNull(loggerMatcherAndConfig.getName(), "logger matcher name");
+        for (int i = 0; i < loggerMatcherAndConfigs.size(); i++) {
+          ExperimentalLoggerMatcherAndConfigModel loggerMatcherAndConfig =
+              loggerMatcherAndConfigs.get(i);
+          String name =
+              context.withConfigPath(
+                  "logger_configurator/development.loggers[" + i + "]",
+                  () -> requireNonNull(context, loggerMatcherAndConfig.getName(), "name"));
           ExperimentalLoggerConfigModel config = loggerMatcherAndConfig.getConfig();
           if (name == null || config == null) {
             continue;