1 files changed, 82 insertions, 24 deletions

diff --git a/container-core/src/main/java/com/yahoo/container/handler/LogReader.java b/container-core/src/main/java/com/yahoo/container/handler/LogReader.java
index 6cb92244522..832b4ec6667 100644
--- a/container-core/src/main/java/com/yahoo/container/handler/LogReader.java
+++ b/container-core/src/main/java/com/yahoo/container/handler/LogReader.java
@@ -1,11 +1,17 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.handler;
 
-import com.yahoo.collections.Pair;
 import com.yahoo.vespa.defaults.Defaults;
 
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
 import java.io.OutputStream;
+import java.io.OutputStreamWriter;
 import java.io.UncheckedIOException;
 import java.nio.file.FileVisitResult;
 import java.nio.file.Files;
@@ -14,13 +20,23 @@ import java.nio.file.Paths;
 import java.nio.file.SimpleFileVisitor;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.time.Instant;
-import java.util.Comparator;
-import java.util.LinkedList;
+import java.time.temporal.ChronoUnit;
+import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.regex.Pattern;
-import java.util.stream.Collectors;
+import java.util.zip.GZIPInputStream;
 import java.util.zip.GZIPOutputStream;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.util.Comparator.comparing;
+
+/**
+ * @author olaaun
+ * @author freva
+ * @author jonmv
+ */
 class LogReader {
 
     private final Path logDirectory;
@@ -35,22 +51,61 @@ class LogReader {
         this.logFilePattern = logFilePattern;
     }
 
-    void writeLogs(OutputStream outputStream, Instant earliestLogThreshold, Instant latestLogThreshold) {
+    void writeLogs(OutputStream outputStream, Instant from, Instant to) {
         try {
-            for (Path file : getMatchingFiles(earliestLogThreshold, latestLogThreshold)) {
-                if (!file.toString().endsWith(".gz") && !(outputStream instanceof GZIPOutputStream)) {
-                    outputStream = new GZIPOutputStream(outputStream);
+            List<Path> logs = getMatchingFiles(from, to);
+            for (int i = 0; i < logs.size(); i++) {
+                Path log = logs.get(i);
+                boolean zipped = log.toString().endsWith(".gz");
+                try (InputStream in = Files.newInputStream(log)) {
+                    InputStream inProxy;
+
+                    // If the log needs filtering, possibly unzip (and rezip) it, and filter its lines on timestamp.
+                    if (i == 0 || i == logs.size() - 1) {
+                        ByteArrayOutputStream buffer = new ByteArrayOutputStream();
+                        try (BufferedReader reader = new BufferedReader(new InputStreamReader(zipped ? new GZIPInputStream(in) : in, UTF_8));
+                             BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(zipped ? new GZIPOutputStream(buffer) : buffer, UTF_8))) {
+                            for (String line; (line = reader.readLine()) != null; ) {
+                                String[] parts = line.split("\t");
+                                if (parts.length != 7)
+                                    continue;
+
+                                Instant at = Instant.EPOCH.plus((long) (Double.parseDouble(parts[0]) * 1_000_000), ChronoUnit.MICROS);
+                                if (at.isAfter(from) && at.isBefore(to)) {
+                                    writer.write(line);
+                                    writer.newLine();
+                                }
+                            }
+                        }
+                        inProxy = new ByteArrayInputStream(buffer.toByteArray());
+                    }
+                    else
+                        inProxy = in;
+
+                    // At the point when logs switch to un-zipped, replace the output stream with a zipping proxy.
+                    if ( ! zipped && ! (outputStream instanceof GZIPOutputStream))
+                        outputStream = new GZIPOutputStream(outputStream);
+
+                    inProxy.transferTo(outputStream);
                 }
-                Files.copy(file, outputStream);
             }
-            outputStream.close();
-        } catch (IOException e) {
+        }
+        catch (IOException e) {
             throw new UncheckedIOException(e);
         }
+        finally {
+            try {
+                outputStream.close();
+            }
+            catch (IOException e) {
+                throw new UncheckedIOException(e);
+            }
+        }
     }
 
-    private List<Path> getMatchingFiles(Instant earliestLogThreshold, Instant latestLogThreshold) {
-        final List<Pair<Path, Instant>> paths = new LinkedList<>();
+    /** Returns log files which may have relevant entries, sorted by modification time — the first and last must be filtered. */
+    private List<Path> getMatchingFiles(Instant from, Instant to) {
+        Map<Path, Instant> paths = new HashMap<>();
         try {
             Files.walkFileTree(logDirectory, new SimpleFileVisitor<>() {
 
@@ -61,12 +116,8 @@ class LogReader {
 
                 @Override
                 public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
-                    Instant lastModified = attrs.lastModifiedTime().toInstant();
-                    if (lastModified.isAfter(earliestLogThreshold) &&
-                            lastModified.isBefore(latestLogThreshold) &&
-                            logFilePattern.matcher(file.getFileName().toString()).matches()) {
-                        paths.add(new Pair<>(file, lastModified));
-                    }
+                    if (logFilePattern.matcher(file.getFileName().toString()).matches())
+                        paths.put(file, attrs.lastModifiedTime().toInstant());
 
                     return FileVisitResult.CONTINUE;
                 }
@@ -76,13 +127,20 @@ class LogReader {
                     return FileVisitResult.CONTINUE;
                 }
             });
-        } catch (IOException e) {
+        }
+        catch (IOException e) {
             throw new UncheckedIOException(e);
         }
 
-        return paths.stream()
-                .sorted(Comparator.comparing(Pair::getSecond))
-                .map(Pair::getFirst)
-                .collect(Collectors.toList());
+        List<Path> sorted = new ArrayList<>();
+        for (var entries = paths.entrySet().stream().sorted(comparing(Map.Entry::getValue)).iterator(); entries.hasNext(); ) {
+            var entry = entries.next();
+            if (entry.getValue().isAfter(from))
+                sorted.add(entry.getKey());
+            if (entry.getValue().isAfter(to))
+                break;
+        }
+        return sorted;
     }
+
 }