Deprecate View File Configuration mechanism (#8133)

Author: jack-berg

sdk-extensions/incubator/README.md

@@ -33,6 +33,9 @@ Notes:
 
 ## View File Configuration
 
+> [!WARNING]
+> This mechanism is superseded by declarative config, which is now stable (spec and schema at [opentelemetry-configuration](https://github.com/open-telemetry/opentelemetry-configuration)) and will be removed after the 1.62.0 release. Please use [declarative configuration](#declarative-configuration) instead.
+
 Adds support for file based YAML configuration of Metric SDK Views.
 
 For example, suppose `/Users/user123/view.yaml` has the following content:

sdk-extensions/incubator/src/main/java/io/opentelemetry/sdk/extension/incubator/metric/viewconfig/ViewConfig.java

@@ -73,7 +73,15 @@
  *             .setAttributesFilter(key -> new HashSet<>(Arrays.asList("foo", "bar")).contains(key))
  *             .build());
  * }</pre>
+ *
+ * @deprecated this mechanism is superseded by declarative config, which is now stable (spec and
+ *     schema at <a
+ *     href="https://github.com/open-telemetry/opentelemetry-configuration">opentelemetry-configuration</a>.
+ *     Please uses {@link
+ *     io.opentelemetry.sdk.extension.incubator.fileconfig.DeclarativeConfiguration#parseAndCreate(InputStream)}
+ *     instead.
  */
+@Deprecated
 public final class ViewConfig {
 
   private ViewConfig() {}

sdk-extensions/incubator/src/main/java/io/opentelemetry/sdk/extension/incubator/metric/viewconfig/ViewConfigCustomizer.java

@@ -15,9 +15,21 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
+import java.util.logging.Logger;
 
-/** SPI implementation for loading view configuration YAML. */
+/**
+ * SPI implementation for loading view configuration YAML.
+ *
+ * @deprecated this mechanism is superseded by declarative config, which is now stable (spec and
+ *     schema at <a
+ *     href="https://github.com/open-telemetry/opentelemetry-configuration">opentelemetry-configuration</a>)
+ *     and will be removed after the 1.62.0 release. Please uses {@link
+ *     io.opentelemetry.sdk.extension.incubator.fileconfig.DeclarativeConfiguration#parseAndCreate(InputStream)}
+ *     instead.
+ */
+@Deprecated
 public final class ViewConfigCustomizer implements AutoConfigurationCustomizerProvider {
+  private static final Logger LOGGER = Logger.getLogger(ViewConfigCustomizer.class.getName());
 
   @Override
   public void customize(AutoConfigurationCustomizer autoConfiguration) {
@@ -29,6 +41,10 @@ static SdkMeterProviderBuilder customizeMeterProvider(
       SdkMeterProviderBuilder meterProviderBuilder, ConfigProperties configProperties) {
     List<String> configFileLocations =
         configProperties.getList("otel.experimental.metrics.view.config");
+    if (!configFileLocations.isEmpty()) {
+      LOGGER.warning(
+          "otel.experimental.metrics.view.config is deprecated and will be removed after 1.62 release. Please use declarative config instead.");
+    }
     for (String configFileLocation : configFileLocations) {
       if (configFileLocation.startsWith("classpath:")) {
         String classpathLocation = configFileLocation.substring("classpath:".length());

sdk-extensions/incubator/src/test/java/io/opentelemetry/sdk/extension/incubator/metric/viewconfig/ViewConfigCustomizerTest.java

@@ -22,6 +22,7 @@
 import java.util.UUID;
 import org.junit.jupiter.api.Test;
 
+@SuppressWarnings("deprecation") // Testing deprecated methods
 class ViewConfigCustomizerTest {
 
   @Test

sdk-extensions/incubator/src/test/java/io/opentelemetry/sdk/extension/incubator/metric/viewconfig/ViewConfigTest.java

@@ -35,6 +35,7 @@
 import org.assertj.core.api.InstanceOfAssertFactories;
 import org.junit.jupiter.api.Test;
 
+@SuppressWarnings("deprecation") // Testing deprecated methods
 class ViewConfigTest {
 
   @Test