Index: oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadata.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadata.java	(revision 70a1c21d487d6458f9891a111eb07a51820d090e)
+++ oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadata.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
@@ -20,21 +20,30 @@
 import java.util.Map;
 import java.util.UUID;
 
+/**
+ * Provides access to the blob metadata.
+ * <p>
+ * In azure blob metadata keys are case-insensitive. A bug in the tool azcopy v10 make each key to start with
+ * an uppercase letter.  To avoid future bugs we should be tolerant in what we read.
+ * <p>
+ * Azure Blobs metadata can not store multiple entries with the same key where only the case differs. Therefore it is
+ * safe to use the same concept in java, see {@link CaseInsensitiveKeysMapAccess}
+ */
 public final class AzureBlobMetadata {
 
-    private static final String METADATA_TYPE = "type";
+    static final String METADATA_TYPE = "type";
 
-    private static final String METADATA_SEGMENT_UUID = "uuid";
+    static final String METADATA_SEGMENT_UUID = "uuid";
 
-    private static final String METADATA_SEGMENT_POSITION = "position";
+    static final String METADATA_SEGMENT_POSITION = "position";
 
-    private static final String METADATA_SEGMENT_GENERATION = "generation";
+    static final String METADATA_SEGMENT_GENERATION = "generation";
 
-    private static final String METADATA_SEGMENT_FULL_GENERATION = "fullGeneration";
+    static final String METADATA_SEGMENT_FULL_GENERATION = "fullGeneration";
 
-    private static final String METADATA_SEGMENT_COMPACTED = "compacted";
+    static final String METADATA_SEGMENT_COMPACTED = "compacted";
 
-    private static final String TYPE_SEGMENT = "segment";
+    static final String TYPE_SEGMENT = "segment";
 
     public static HashMap<String, String> toSegmentMetadata(AzureSegmentArchiveEntry indexEntry) {
         HashMap<String, String> map = new HashMap<>();
@@ -48,18 +57,23 @@
     }
 
     public static AzureSegmentArchiveEntry toIndexEntry(Map<String, String> metadata, int length) {
-        UUID uuid = UUID.fromString(metadata.get(METADATA_SEGMENT_UUID));
+        Map<String, String> caseInsensitiveMetadata = CaseInsensitiveKeysMapAccess.convert(metadata);
+
+
+        UUID uuid = UUID.fromString(caseInsensitiveMetadata.get(METADATA_SEGMENT_UUID));
         long msb = uuid.getMostSignificantBits();
         long lsb = uuid.getLeastSignificantBits();
-        int position = Integer.parseInt(metadata.get(METADATA_SEGMENT_POSITION));
-        int generation = Integer.parseInt(metadata.get(METADATA_SEGMENT_GENERATION));
-        int fullGeneration = Integer.parseInt(metadata.get(METADATA_SEGMENT_FULL_GENERATION));
-        boolean compacted = Boolean.parseBoolean(metadata.get(METADATA_SEGMENT_COMPACTED));
+        int position = Integer.parseInt(caseInsensitiveMetadata.get(METADATA_SEGMENT_POSITION));
+        int generation = Integer.parseInt(caseInsensitiveMetadata.get(METADATA_SEGMENT_GENERATION));
+        int fullGeneration = Integer.parseInt(caseInsensitiveMetadata.get(METADATA_SEGMENT_FULL_GENERATION));
+        boolean compacted = Boolean.parseBoolean(caseInsensitiveMetadata.get(METADATA_SEGMENT_COMPACTED));
         return new AzureSegmentArchiveEntry(msb, lsb, position, length, generation, fullGeneration, compacted);
     }
 
     public static boolean isSegment(Map<String, String> metadata) {
-        return metadata != null && TYPE_SEGMENT.equals(metadata.get(METADATA_TYPE));
+        Map<String, String> caseInsensitiveMetadata = CaseInsensitiveKeysMapAccess.convert(metadata);
+
+        return metadata != null && TYPE_SEGMENT.equals(caseInsensitiveMetadata.get(METADATA_TYPE));
     }
 
 }
Index: oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureJournalFile.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureJournalFile.java	(revision 70a1c21d487d6458f9891a111eb07a51820d090e)
+++ oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/AzureJournalFile.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
@@ -33,6 +33,7 @@
 import java.util.Comparator;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -125,9 +126,10 @@
                     if (!metadataFetched) {
                         blob.downloadAttributes();
                         metadataFetched = true;
-                        if (blob.getMetadata().containsKey("lastEntry")) {
+                        Map<String, String> metadata = CaseInsensitiveKeysMapAccess.convert(blob.getMetadata());
+                        if (metadata.containsKey("lastEntry")) {
                             firstLineReturned = true;
-                            return blob.getMetadata().get("lastEntry");
+                            return metadata.get("lastEntry");
                         }
                     }
                     reader = new ReverseFileReader(blob);
Index: oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadataTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadataTest.java	(revision 467638857b9a0692d8bfcca4b0fe832a7eafdfd2)
+++ oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/AzureBlobMetadataTest.java	(revision 467638857b9a0692d8bfcca4b0fe832a7eafdfd2)
@@ -0,0 +1,82 @@
+package org.apache.jackrabbit.oak.segment.azure;
+
+import org.junit.Test;
+
+import java.util.Collections;
+import java.util.HashMap;
+
+import static org.junit.Assert.*;
+
+public class AzureBlobMetadataTest {
+
+    @Test
+    public void toSegmentMetadata() {
+        AzureSegmentArchiveEntry entry = new AzureSegmentArchiveEntry(-7554506325726244935L, -5874985927363300041L,
+                3, 5, 50, 60, true);
+        HashMap<String, String> map = AzureBlobMetadata.toSegmentMetadata(entry);
+
+        assertEquals("segment", map.get(AzureBlobMetadata.METADATA_TYPE));
+        assertEquals("97290085-b1a5-4fb9-ae77-db6d13177537", map.get(AzureBlobMetadata.METADATA_SEGMENT_UUID));
+        assertEquals("3", map.get(AzureBlobMetadata.METADATA_SEGMENT_POSITION));
+        assertEquals("50", map.get(AzureBlobMetadata.METADATA_SEGMENT_GENERATION));
+        assertEquals("60", map.get(AzureBlobMetadata.METADATA_SEGMENT_FULL_GENERATION));
+        assertEquals("true", map.get(AzureBlobMetadata.METADATA_SEGMENT_COMPACTED));
+    }
+
+
+    @Test
+    public void toIndexEntry() {
+        HashMap<String, String> metadata = new HashMap<>();
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_UUID, "97290085-b1a5-4fb9-ae77-db6d13177537");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_POSITION, "3");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_GENERATION, "50");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_FULL_GENERATION, "60");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_COMPACTED, "true");
+        AzureSegmentArchiveEntry azureSegmentArchiveEntry = AzureBlobMetadata.toIndexEntry(metadata, 5);
+        System.out.println(azureSegmentArchiveEntry);
+
+
+        assertEquals(-7554506325726244935L, azureSegmentArchiveEntry.getMsb());
+        assertEquals(-5874985927363300041L, azureSegmentArchiveEntry.getLsb());
+        assertEquals(3, azureSegmentArchiveEntry.getPosition());
+        assertEquals(5, azureSegmentArchiveEntry.getLength());
+        assertEquals(50, azureSegmentArchiveEntry.getGeneration());
+        assertEquals(60, azureSegmentArchiveEntry.getFullGeneration());
+        assertTrue(azureSegmentArchiveEntry.isCompacted());
+    }
+
+
+    @Test
+    public void toIndexEntry_caseInsensitive() {
+        HashMap<String, String> metadata = new HashMap<>();
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_UUID.toUpperCase(), "97290085-b1a5-4fb9-ae77-db6d13177537");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_POSITION.toUpperCase(), "3");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_GENERATION.toUpperCase(), "50");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_FULL_GENERATION.toUpperCase(), "60");
+        metadata.put(AzureBlobMetadata.METADATA_SEGMENT_COMPACTED.toUpperCase(), "true");
+        AzureSegmentArchiveEntry azureSegmentArchiveEntry = AzureBlobMetadata.toIndexEntry(metadata, 5);
+
+        assertEquals(-7554506325726244935L, azureSegmentArchiveEntry.getMsb());
+        assertEquals(-5874985927363300041L, azureSegmentArchiveEntry.getLsb());
+        assertEquals(3, azureSegmentArchiveEntry.getPosition());
+        assertEquals(5, azureSegmentArchiveEntry.getLength());
+        assertEquals(50, azureSegmentArchiveEntry.getGeneration());
+        assertEquals(60, azureSegmentArchiveEntry.getFullGeneration());
+        assertTrue(azureSegmentArchiveEntry.isCompacted());
+    }
+
+    @Test
+    public void isSegment() {
+        assertTrue(AzureBlobMetadata.isSegment(Collections.singletonMap("type", "segment")));
+
+        assertFalse(AzureBlobMetadata.isSegment(Collections.singletonMap("type", "index")));
+    }
+
+
+    @Test
+    public void isSegment_caseInsensitive() {
+        assertTrue(AzureBlobMetadata.isSegment(Collections.singletonMap("Type", "segment")));
+        assertTrue(AzureBlobMetadata.isSegment(Collections.singletonMap("TYPE", "segment")));
+        assertTrue(AzureBlobMetadata.isSegment(Collections.singletonMap("tYPE", "segment")));
+    }
+}
Index: oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccess.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccess.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
+++ oak-segment-azure/src/main/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccess.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
@@ -0,0 +1,30 @@
+package org.apache.jackrabbit.oak.segment.azure;
+
+import java.util.Collections;
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ * Wrapper around the map that allows accessing the map with case-insensitive keys.
+ * For example, the keys 'hello' and 'Hello' access the same value.
+ */
+public class CaseInsensitiveKeysMapAccess {
+
+    /**
+     * Wrapper around the map that allows accessing the map with case-insensitive keys.
+     * <p>
+     * Return an unmodifiable map to make it clear that changes are not reflected to the original map.
+     *
+     * @param map the map to convert
+     * @return an unmodifiable map with case-insensitive key access
+     */
+    public static Map<String, String> convert(Map<String, String> map) {
+        Map<String, String> caseInsensitiveMap = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);
+        if (map != null) {
+            caseInsensitiveMap.putAll(map);
+        }
+        // return an unmodifiable map to make it clear that changes are not reflected in the original map.
+        return Collections.unmodifiableMap(caseInsensitiveMap);
+    }
+
+}
Index: oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccessTest.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccessTest.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
+++ oak-segment-azure/src/test/java/org/apache/jackrabbit/oak/segment/azure/CaseInsensitiveKeysMapAccessTest.java	(revision 03fcf4566227f57021bfe942aaf76851318deb5a)
@@ -0,0 +1,26 @@
+package org.apache.jackrabbit.oak.segment.azure;
+
+import org.junit.Test;
+
+import java.util.Collections;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+
+public class CaseInsensitiveKeysMapAccessTest {
+
+    @Test
+    public void convert() {
+        Map<String, String> map = CaseInsensitiveKeysMapAccess.convert(Collections.singletonMap("hello", "world"));
+
+        assertEquals("world", map.get("hello"));
+        assertEquals("world", map.get("Hello"));
+        assertEquals("world", map.get("hELLO"));
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void assertImmutable() {
+        Map<String, String> map = CaseInsensitiveKeysMapAccess.convert(Collections.singletonMap("hello", "world"));
+        map.put("foo", "bar");
+    }
+}