From 2344e0738e9ed65061273103f791dca56d9f42ab Mon Sep 17 00:00:00 2001
From: Frank Chen <frank.chen021@outlook.com>
Date: Fri, 23 Sep 2022 11:32:21 +0800
Subject: [PATCH] Keep compatibility during upgrading

---
 src/Common/OpenTelemetryTraceContext.cpp |  6 ++---
 src/Interpreters/DDLTask.cpp             | 32 ++++++++++++++++--------
 src/Interpreters/DDLTask.h               |  5 ++++
 3 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/src/Common/OpenTelemetryTraceContext.cpp b/src/Common/OpenTelemetryTraceContext.cpp
index 3e7a172bdb2..515060803d6 100644
--- a/src/Common/OpenTelemetryTraceContext.cpp
+++ b/src/Common/OpenTelemetryTraceContext.cpp
@@ -228,8 +228,7 @@ String TracingContext::composeTraceparentHeader() const
 
 void TracingContext::deserialize(ReadBuffer & buf)
 {
-    buf >> "tracing: "
-        >> this->trace_id
+    buf >> this->trace_id
         >> "\n"
         >> this->span_id
         >> "\n"
@@ -241,8 +240,7 @@ void TracingContext::deserialize(ReadBuffer & buf)
 
 void TracingContext::serialize(WriteBuffer & buf) const
 {
-    buf << "tracing: "
-        << this->trace_id
+    buf << this->trace_id
         << "\n"
         << this->span_id
         << "\n"
diff --git a/src/Interpreters/DDLTask.cpp b/src/Interpreters/DDLTask.cpp
index aff47db8242..73105ae003e 100644
--- a/src/Interpreters/DDLTask.cpp
+++ b/src/Interpreters/DDLTask.cpp
@@ -50,21 +50,26 @@ bool HostID::isLocalAddress(UInt16 clickhouse_port) const
 
 void DDLLogEntry::assertVersion() const
 {
-    constexpr UInt64 max_version = 2;
-    if (version == 0 || max_version < version)
+    if (version == 0 
+    /// NORMALIZE_CREATE_ON_INITIATOR_VERSION does not change the entry format, it uses versioin 2, so there shouldn't be version 3
+    || version == NORMALIZE_CREATE_ON_INITIATOR_VERSION
+    || version > MAX_VERSION)
         throw Exception(ErrorCodes::UNKNOWN_FORMAT_VERSION, "Unknown DDLLogEntry format version: {}."
-                                                            "Maximum supported version is {}", version, max_version);
+                                                            "Maximum supported version is {}", version, MAX_VERSION);
 }
 
 void DDLLogEntry::setSettingsIfRequired(ContextPtr context)
 {
-    version = context->getSettingsRef().distributed_ddl_entry_format_version;
+    version = context->getSettingsRef().    ;
+    if (version <= 0 || version > MAX_VERSION)
+        throw Exception(ErrorCodes::UNKNOWN_FORMAT_VERSION, "Unknown distributed_ddl_entry_format_version: {}."
+                                                            "Maximum supported version is {}.", version, MAX_VERSION);
 
     /// NORMALIZE_CREATE_ON_INITIATOR_VERSION does not affect entry format in ZooKeeper
     if (version == NORMALIZE_CREATE_ON_INITIATOR_VERSION)
         version = SETTINGS_IN_ZK_VERSION;
 
-    if (version == SETTINGS_IN_ZK_VERSION)
+    if (version >= SETTINGS_IN_ZK_VERSION)
         settings.emplace(context->getSettingsRef().changes());
 }
 
@@ -94,7 +99,8 @@ String DDLLogEntry::toString() const
         wb << "settings: " << serializeAST(ast) << "\n";
     }
 
-    wb << this->tracing_context;
+    if (version >= OPENTELEMETRY_ENABLED_VERSION)
+        wb << "tracing: " << this->tracing_context;
 
     return wb.str();
 }
@@ -108,7 +114,7 @@ void DDLLogEntry::parse(const String & data)
 
     Strings host_id_strings;
     rb >> "query: " >> escape >> query >> "\n";
-    if (version == 1)
+    if (version == OLDEST_VERSION)
     {
         rb >> "hosts: " >> host_id_strings >> "\n";
 
@@ -117,9 +123,8 @@ void DDLLogEntry::parse(const String & data)
         else
             initiator.clear();
     }
-    else if (version == 2)
+    else if (version >= SETTINGS_IN_ZK_VERSION)
     {
-
         if (!rb.eof() && *rb.position() == 'h')
             rb >> "hosts: " >> host_id_strings >> "\n";
         if (!rb.eof() && *rb.position() == 'i')
@@ -136,8 +141,13 @@ void DDLLogEntry::parse(const String & data)
         }
     }
 
-    if (!rb.eof() && *rb.position() == 't')
-        rb >> this->tracing_context;
+    if (version >= OPENTELEMETRY_ENABLED_VERSION)
+    {
+        if (!rb.eof() && *rb.position() == 't')
+            rb >> "tracing: " >> this->tracing_context;
+    }
+
+    assertEOF(rb);
 
     if (!host_id_strings.empty())
     {
diff --git a/src/Interpreters/DDLTask.h b/src/Interpreters/DDLTask.h
index fc85188a865..7217ee2b98b 100644
--- a/src/Interpreters/DDLTask.h
+++ b/src/Interpreters/DDLTask.h
@@ -70,6 +70,11 @@ struct DDLLogEntry
     static constexpr const UInt64 OLDEST_VERSION = 1;
     static constexpr const UInt64 SETTINGS_IN_ZK_VERSION = 2;
     static constexpr const UInt64 NORMALIZE_CREATE_ON_INITIATOR_VERSION = 3;
+    static constexpr const UInt64 OPENTELEMETRY_ENABLED_VERSION = 4;
+    /// Add new version here
+
+    /// Remember to update the value below once new version is added
+    static constexpr const UInt64 MAX_VERSION = 4;
 
     UInt64 version = 1;
     String query;