From 53bcfb3107ef76cfcfc7d76902cfc8d1bf9378c1 Mon Sep 17 00:00:00 2001
From: Andrea Lamparelli <a.lamparelli95@gmail.com>
Date: Wed, 21 Feb 2024 14:46:07 +0100
Subject: [PATCH] Revert "return finished strings from EscapeString"

This reverts commit b0db34cefa074eb1d8fdb1aa9695f027af6e2f59.
---
 ml_metadata/metadata_store/mysql_metadata_source.cc      | 2 +-
 ml_metadata/metadata_store/postgresql_metadata_source.cc | 6 +++++-
 ml_metadata/metadata_store/postgresql_query_executor.cc  | 8 ++++----
 ml_metadata/metadata_store/query_config_executor.cc      | 4 ++--
 4 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/ml_metadata/metadata_store/mysql_metadata_source.cc b/ml_metadata/metadata_store/mysql_metadata_source.cc
index 9daf02500..ba6dfb12c 100644
--- a/ml_metadata/metadata_store/mysql_metadata_source.cc
+++ b/ml_metadata/metadata_store/mysql_metadata_source.cc
@@ -402,7 +402,7 @@ std::string MySqlMetadataSource::EscapeString(absl::string_view value) const {
   CHECK(mysql_real_escape_string(db_, buffer, value.data(), value.length()) !=
         -1UL)
       << "NO_BACKSLASH_ESCAPES SQL mode should not be enabled.";
-  std::string result = absl::StrCat("'", buffer, "'");
+  std::string result(buffer);
   delete[] buffer;
   return result;
 }
diff --git a/ml_metadata/metadata_store/postgresql_metadata_source.cc b/ml_metadata/metadata_store/postgresql_metadata_source.cc
index 40b79180c..966527b96 100644
--- a/ml_metadata/metadata_store/postgresql_metadata_source.cc
+++ b/ml_metadata/metadata_store/postgresql_metadata_source.cc
@@ -315,8 +315,12 @@ std::string PostgreSQLMetadataSource::EscapeString(
 
   char* escaped_str = PQescapeLiteral(conn_, value.data(), value.size());
   std::string result{escaped_str};
+  // PQescapeLiteral will wrap the escaped string in '', which is redundant to
+  // the existing MLMD syntax. Therefore stripping the outer '' from the escaped
+  // string.
+  std::string substring = result.substr(1, std::strlen(result.data()) - 2);
   PQfreemem(escaped_str);
-  return result;
+  return substring;
 }
 
 std::string PostgreSQLMetadataSource::EncodeBytes(
diff --git a/ml_metadata/metadata_store/postgresql_query_executor.cc b/ml_metadata/metadata_store/postgresql_query_executor.cc
index ab0db89d4..501a9251b 100644
--- a/ml_metadata/metadata_store/postgresql_query_executor.cc
+++ b/ml_metadata/metadata_store/postgresql_query_executor.cc
@@ -374,10 +374,10 @@ absl::Status PostgreSQLQueryExecutor::DowngradeMetadataSource(
   return absl::OkStatus();
 }
 std::string PostgreSQLQueryExecutor::Bind(const char* value) {
-  return metadata_source_->EscapeString(value);
+  return absl::StrCat("'", metadata_source_->EscapeString(value), "'");
 }
 std::string PostgreSQLQueryExecutor::Bind(absl::string_view value) {
-  return metadata_source_->EscapeString(value);
+  return absl::StrCat("'", metadata_source_->EscapeString(value), "'");
 }
 std::string PostgreSQLQueryExecutor::Bind(int value) {
   return std::to_string(value);
@@ -390,10 +390,10 @@ std::string PostgreSQLQueryExecutor::Bind(double value) {
 }
 std::string PostgreSQLQueryExecutor::Bind(const google::protobuf::Any& value) {
   return absl::StrCat(
-      "decode(",
+      "decode('",
       metadata_source_->EscapeString(
           metadata_source_->EncodeBytes(value.SerializeAsString())),
-      ", 'base64')");
+      "', 'base64')");
 }
 std::string PostgreSQLQueryExecutor::Bind(bool value) {
   return value ? "TRUE" : "FALSE";
diff --git a/ml_metadata/metadata_store/query_config_executor.cc b/ml_metadata/metadata_store/query_config_executor.cc
index 094a7abd4..d369a511d 100644
--- a/ml_metadata/metadata_store/query_config_executor.cc
+++ b/ml_metadata/metadata_store/query_config_executor.cc
@@ -283,11 +283,11 @@ absl::Status QueryConfigExecutor::DowngradeMetadataSource(
 }
 
 std::string QueryConfigExecutor::Bind(const char* value) {
-  return metadata_source_->EscapeString(value);
+  return absl::StrCat("'", metadata_source_->EscapeString(value), "'");
 }
 
 std::string QueryConfigExecutor::Bind(absl::string_view value) {
-  return metadata_source_->EscapeString(value);
+  return absl::StrCat("'", metadata_source_->EscapeString(value), "'");
 }
 
 std::string QueryConfigExecutor::Bind(int value) {