Diskbuffering config and README updates (#1169)

Author: LikeTheSalad

disk-buffering/README.md

@@ -55,7 +55,7 @@ Each wrapper will need the following when instantiating them:
 * A File instance of the root directory where all the data is going to be written. The same root dir
   can be used for all the wrappers, since each will create their own folder inside it.
 * An instance
-  of [StorageConfiguration](src/main/java/io/opentelemetry/contrib/disk/buffering/internal/StorageConfiguration.java)
+  of [StorageConfiguration](src/main/java/io/opentelemetry/contrib/disk/buffering/StorageConfiguration.java)
   with the desired parameters. You can create one with default values by
   calling `StorageConfiguration.getDefault()`.
 
@@ -64,16 +64,21 @@ take care of always storing the data it receives.
 
 #### Set up example for spans
 
+### Writing data
+
+The data is written in the disk by "ToDisk" exporters, these are exporters that serialize and store the data as received by their processors. If for some reason
+the "ToDisk" cannot store data in the disk, they'll delegate the data to their wrapped exporter.
+
 ```java
 // Creating the SpanExporter of our choice.
 SpanExporter mySpanExporter = OtlpGrpcSpanExporter.getDefault();
 
-// Wrapping our exporter with its disk exporter.
-SpanDiskExporter diskExporter = SpanDiskExporter.create(mySpanExporter, new File("/my/signals/cache/dir"), StorageConfiguration.getDefault());
+// Wrapping our exporter with its "ToDisk" exporter.
+SpanToDiskExporter toDiskExporter = SpanToDiskExporter.create(mySpanExporter, StorageConfiguration.getDefault(new File("/my/signals/cache/dir")));
 
  // Registering the disk exporter within our OpenTelemetry instance.
 SdkTracerProvider myTraceProvider = SdkTracerProvider.builder()
-        .addSpanProcessor(SimpleSpanProcessor.create(diskExporter))
+        .addSpanProcessor(SimpleSpanProcessor.create(toDiskExporter))
         .build();
 OpenTelemetrySdk.builder()
         .setTracerProvider(myTraceProvider)
@@ -83,12 +88,13 @@ OpenTelemetrySdk.builder()
 
 ### Reading data
 
-Each of the exporter wrappers can read from the disk and send the retrieved data over to their
-wrapped exporter by calling this method from them:
+In order to read data, we need to create "FromDisk" exporters, which read data from the disk, parse it and delegate it
+to their wrapped exporters.
 
 ```java
 try {
-    if(diskExporter.exportStoredBatch(1, TimeUnit.SECONDS)) {
+    SpanFromDiskExporter fromDiskExporter = SpanFromDiskExporter.create(memorySpanExporter, storageConfig);
+    if(fromDiskExporter.exportStoredBatch(1, TimeUnit.SECONDS)) {
         // A batch was successfully exported and removed from disk. You can call this method for as long as it keeps returning true.
     } else {
         // Either there was no data in the disk or the wrapped exporter returned CompletableResultCode.ofFailure().

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/LogRecordFromDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporterImpl;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.deserializers.SignalDeserializer;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/LogRecordToDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.ToDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.serializers.SignalSerializer;
 import io.opentelemetry.sdk.common.CompletableResultCode;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/MetricFromDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporterImpl;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.deserializers.SignalDeserializer;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/MetricToDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.ToDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.serializers.SignalSerializer;
 import io.opentelemetry.sdk.common.CompletableResultCode;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/SpanFromDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.FromDiskExporterImpl;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.deserializers.SignalDeserializer;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/SpanToDiskExporter.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.contrib.disk.buffering;
 
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.exporter.ToDiskExporter;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.serializers.SignalSerializer;
 import io.opentelemetry.sdk.common.CompletableResultCode;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/internal/StorageConfiguration.java renamed to disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/StorageConfiguration.java

@@ -3,7 +3,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
-package io.opentelemetry.contrib.disk.buffering.internal;
+package io.opentelemetry.contrib.disk.buffering;
 
 import com.google.auto.value.AutoValue;
 import io.opentelemetry.contrib.disk.buffering.internal.files.DefaultTemporaryFileProvider;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/internal/exporter/FromDiskExporterBuilder.java

@@ -8,7 +8,7 @@
 import static java.util.Collections.emptyList;
 
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
+import io.opentelemetry.contrib.disk.buffering.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.deserializers.SignalDeserializer;
 import io.opentelemetry.contrib.disk.buffering.internal.storage.Storage;
 import io.opentelemetry.contrib.disk.buffering.internal.storage.StorageBuilder;

disk-buffering/src/main/java/io/opentelemetry/contrib/disk/buffering/internal/exporter/ToDiskExporterBuilder.java

@@ -6,7 +6,7 @@
 package io.opentelemetry.contrib.disk.buffering.internal.exporter;
 
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
-import io.opentelemetry.contrib.disk.buffering.internal.StorageConfiguration;
+import io.opentelemetry.contrib.disk.buffering.StorageConfiguration;
 import io.opentelemetry.contrib.disk.buffering.internal.serialization.serializers.SignalSerializer;
 import io.opentelemetry.contrib.disk.buffering.internal.storage.Storage;
 import io.opentelemetry.contrib.disk.buffering.internal.storage.StorageBuilder;