Track SQL migrations

repositories/MigrationRunner.cc

@@ -6,6 +6,7 @@
 #include <cctype>
 #include <filesystem>
 #include <fstream>
+#include <optional>
 #include <sstream>
 #include <string>
 #include <vector>
@@ -63,6 +64,13 @@ std::vector<std::string> splitStatements(const std::string &sql)
     }
     return statements;
 }
+
+bool hasMigration(const drogon::orm::DbClientPtr &db, const std::string &name)
+{
+    const auto result = db->execSqlSync(
+        "SELECT name FROM schema_migrations WHERE name = ? LIMIT 1", name);
+    return !result.empty();
+}
 }  // namespace
 
 void MigrationRunner::run(const std::string &directory)
@@ -86,8 +94,20 @@ void MigrationRunner::run(const std::string &directory)
     std::sort(files.begin(), files.end());
 
     auto db = drogon::app().getDbClient();
+    db->execSqlSync(
+        "CREATE TABLE IF NOT EXISTS schema_migrations ("
+        "name VARCHAR(255) NOT NULL PRIMARY KEY, "
+        "applied_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP"
+        ")");
+
     for (const auto &file : files)
     {
+        const auto name = file.filename().string();
+        if (hasMigration(db, name))
+        {
+            continue;
+        }
+
         std::ifstream input(file);
         std::stringstream buffer;
         buffer << input.rdbuf();
@@ -96,8 +116,8 @@ void MigrationRunner::run(const std::string &directory)
         {
             db->execSqlSync(statement);
         }
-        LOG_INFO << "Applied migration " << file.string();
+        db->execSqlSync("INSERT INTO schema_migrations (name) VALUES (?)", name);
+        LOG_INFO << "Applied migration " << name;
     }
 }
 }  // namespace visione::repositories
-