From c94e52f697cdae67c35fe8cb0f95088029231b95 Mon Sep 17 00:00:00 2001
From: David Steele <david@pgmasters.net>
Date: Mon, 16 Oct 2017 14:34:44 -0400
Subject: [PATCH] Remove error when overlapping timelines are detected.

Overlapping timelines are valid in many Point-in-Time-Recovery (PITR) scenarios.

Reported by blogh.
---
 doc/xml/release.xml                           | 10 +++++
 lib/pgBackRest/Archive/Common.pm              | 45 +++++--------------
 lib/pgBackRest/Backup/Backup.pm               |  4 +-
 .../Module/Archive/ArchiveCommonTest.pm       | 19 --------
 4 files changed, 24 insertions(+), 54 deletions(-)

diff --git a/doc/xml/release.xml b/doc/xml/release.xml
index 5e19fd06d..3a3477f3f 100644
--- a/doc/xml/release.xml
+++ b/doc/xml/release.xml
@@ -12,6 +12,16 @@
     <release-list>
         <release date="XXXX-XX-XX" version="1.25dev" title="UNDER DEVELOPMENT">
             <release-core-list>
+                <release-bug-list>
+                    <release-item>
+                        <release-item-contributor-list>
+                            <release-item-ideator id="lobréau.benoit"/>
+                        </release-item-contributor-list>
+
+                        <p>Remove error when overlapping timelines are detected.  Overlapping timelines are valid in many Point-in-Time-Recovery (PITR) scenarios.</p>
+                    </release-item>
+                </release-bug-list>
+
                 <release-refactor-list>
                     <release-item>
                         <p>Update C naming conventions.</p>
diff --git a/lib/pgBackRest/Archive/Common.pm b/lib/pgBackRest/Archive/Common.pm
index 879e97818..83682b127 100644
--- a/lib/pgBackRest/Archive/Common.pm
+++ b/lib/pgBackRest/Archive/Common.pm
@@ -281,9 +281,7 @@ sub walSegmentFind
         );
 
     # Error if not a segment
-    my $bTimeline = $strWalSegment =~ /^[0-F]{16}$/ ? false : true;
-
-    if ($bTimeline && !walIsSegment($strWalSegment))
+    if (!walIsSegment($strWalSegment))
     {
         confess &log(ERROR, "${strWalSegment} is not a WAL segment", ERROR_ASSERT);
     }
@@ -294,35 +292,13 @@ sub walSegmentFind
 
     do
     {
-        # If the WAL segment includes the timeline then use it, otherwise contruct a regexp with the major WAL part to find paths
-        # where the wal could be found.
-        my @stryTimelineMajor;
-
-        if ($bTimeline)
-        {
-            @stryTimelineMajor = (substr($strWalSegment, 0, 16));
-        }
-        else
-        {
-            @stryTimelineMajor = $oStorageRepo->list(
-                STORAGE_REPO_ARCHIVE . "/${strArchiveId}",
-                {strExpression => '[0-F]{8}' . substr($strWalSegment, 0, 8), bIgnoreMissing => true});
-        }
-
-        # Search each timelin/major path
-        foreach my $strTimelineMajor (@stryTimelineMajor)
-        {
-            # Construct the name of the WAL segment to find
-            my $strWalSegmentFind = $bTimeline ? substr($strWalSegment, 0, 24) : $strTimelineMajor . substr($strWalSegment, 8, 16);
-
-            # Get the name of the requested WAL segment (may have hash info and compression extension)
-            push(@stryWalFileName, $oStorageRepo->list(
-                STORAGE_REPO_ARCHIVE . "/${strArchiveId}/${strTimelineMajor}",
-                {strExpression =>
-                    "^${strWalSegmentFind}" . (walIsPartial($strWalSegment) ? "\\.partial" : '') .
-                    "-[0-f]{40}(\\." . COMPRESS_EXT . "){0,1}\$",
-                    bIgnoreMissing => true}));
-        }
+        # Get the name of the requested WAL segment (may have compression extension)
+        push(@stryWalFileName, $oStorageRepo->list(
+            STORAGE_REPO_ARCHIVE . "/${strArchiveId}/" . substr($strWalSegment, 0, 16),
+            {strExpression =>
+                '^' . substr($strWalSegment, 0, 24) . (walIsPartial($strWalSegment) ? "\\.partial" : '') .
+                "-[0-f]{40}(\\." . COMPRESS_EXT . "){0,1}\$",
+                bIgnoreMissing => true}));
     }
     while (@stryWalFileName == 0 && waitMore($oWait));
 
@@ -331,8 +307,9 @@ sub walSegmentFind
     if (@stryWalFileName > 1)
     {
         confess &log(ERROR,
-            "duplicates found in archive for WAL segment " . ($bTimeline ? $strWalSegment : "XXXXXXXX${strWalSegment}") . ': ' .
-            join(', ', @stryWalFileName), ERROR_ARCHIVE_DUPLICATE);
+            "duplicates found in archive for WAL segment ${strWalSegment}: " . join(', ', @stryWalFileName) .
+            "\nHINT: are multiple primaries archiving to this stanza?",
+            ERROR_ARCHIVE_DUPLICATE);
     }
 
     # If waiting and no WAL segment was found then throw an error
diff --git a/lib/pgBackRest/Backup/Backup.pm b/lib/pgBackRest/Backup/Backup.pm
index 67ff5de2e..f37ea6dc3 100644
--- a/lib/pgBackRest/Backup/Backup.pm
+++ b/lib/pgBackRest/Backup/Backup.pm
@@ -889,7 +889,9 @@ sub process
 
         foreach my $strArchive (@stryArchive)
         {
-            my $strArchiveFile = walSegmentFind($oStorageRepo, $strArchiveId, $strArchive, cfgOption(CFGOPT_ARCHIVE_TIMEOUT));
+            my $strArchiveFile = walSegmentFind(
+                $oStorageRepo, $strArchiveId, substr($strArchiveStop, 0, 8) . $strArchive, cfgOption(CFGOPT_ARCHIVE_TIMEOUT));
+
             $strArchive = substr($strArchiveFile, 0, 24);
 
             if (cfgOption(CFGOPT_ARCHIVE_COPY))
diff --git a/test/lib/pgBackRestTest/Module/Archive/ArchiveCommonTest.pm b/test/lib/pgBackRestTest/Module/Archive/ArchiveCommonTest.pm
index 56fe38336..bb87e09f5 100644
--- a/test/lib/pgBackRestTest/Module/Archive/ArchiveCommonTest.pm
+++ b/test/lib/pgBackRestTest/Module/Archive/ArchiveCommonTest.pm
@@ -130,11 +130,6 @@ sub run
         $self->testResult(
             sub {walSegmentFind(storageRepo(), $strArchiveId, $strWalSegment)}, $strWalSegmentHash, "${strWalSegment} WAL found");
 
-        #---------------------------------------------------------------------------------------------------------------------------
-        $self->testResult(
-            sub {walSegmentFind(storageRepo(), $strArchiveId, substr($strWalSegment, 8, 16))}, $strWalSegmentHash,
-            "${strWalSegment} WAL found without timeline");
-
         #---------------------------------------------------------------------------------------------------------------------------
         my $strWalSegmentHash2 = "${strWalSegment}-a0b0d38b8aa263e25b8ff52a0a4ba85b6be97f9b.gz";
 
@@ -144,21 +139,7 @@ sub run
             sub {walSegmentFind(storageRepo(), $strArchiveId, $strWalSegment)}, ERROR_ARCHIVE_DUPLICATE,
             "duplicates found in archive for WAL segment ${strWalSegment}: ${strWalSegmentHash}, ${strWalSegmentHash2}");
 
-        #---------------------------------------------------------------------------------------------------------------------------
-        my $strWalSegment3 = '00000002' . substr($strWalSegment, 8, 16);
-        my $strWalSegmentHash3 = "${strWalSegment3}-dcdd09246e1918e88c67cf44b35edc23b803d879";
-        my $strWalMajorPath3 = "${strArchivePath}/" . substr($strWalSegment3, 0, 16);
-
-        storageRepo()->pathCreate($strWalMajorPath3, {bCreateParent => true});
-        storageRepo()->put("${strWalMajorPath3}/${strWalSegmentHash3}");
-
-        $self->testException(
-            sub {walSegmentFind(storageRepo(), $strArchiveId, substr($strWalSegment, 8, 16))}, ERROR_ARCHIVE_DUPLICATE,
-            "duplicates found in archive for WAL segment XXXXXXXX" . substr($strWalSegment, 8, 16) .
-            ": ${strWalSegmentHash}, ${strWalSegmentHash2}, ${strWalSegmentHash3}");
-
         storageRepo()->remove("${strWalMajorPath}/${strWalSegmentHash}");
-        storageRepo()->remove("${strWalMajorPath3}/${strWalSegmentHash3}");
 
         #---------------------------------------------------------------------------------------------------------------------------
         $self->testResult(