initial work on query engine, only rough draft of the first level of the arhitecture, implementation is still empty

cypher/common.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include "utils/command_line/arguments.hpp"
+#include "utils/string/filereader.hpp"
+
+std::string extract_query(const vector_str& arguments)
+{
+    if (contain_argument(arguments, "-q"))
+        return get_argument(arguments, "-q", "CREATE (n) RETURN n");
+    auto default_file = "query.cypher";
+    auto file = get_argument(arguments, "-f", default_file);
+    // TODO: error handling
+    return read_file(file.c_str());
+}
+

cypher/parser.cpp

@@ -6,8 +6,7 @@
 #include "debug/tree_print.hpp"
 #include "codegen/cppgen.hpp"
 #include "utils/command_line/arguments.hpp"
-#include "utils/string/filereader.hpp"
-
+#include "cypher/common.hpp"
 #include "utils/terminate_handler.hpp"
 
 using std::cout;
@@ -17,17 +16,7 @@ using std::endl;
 // -q -> query
 // -v -> visitor
 // -f -> file
-
-std::string extract_query(const vector_str& arguments)
-{
-    if (contain_argument(arguments, "-q"))
-        return get_argument(arguments, "-q", "CREATE (n {a:1, b:2}) RETURN n");
-    auto default_file = "query/read/match/match-where.cypher";
-    auto file = get_argument(arguments, "-f", default_file);
-    // TODO: error handling
-    return read_file(file.c_str());
-}
-
+//
 int main(int argc, char *argv[])
 {
     std::set_terminate(&terminate_handler);

cypher/query/write/create.cypher

@@ -1 +1 @@
-CREATE (n {name: "value"})
+CREATE (n {name: "Roy", surname: "Keane"})

query_engine/code_compiler.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+class CodeCompiler
+{
+};

query_engine/code_generator.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+class CodeGenerator
+{
+};

query_engine/main.cpp

@@ -0,0 +1,23 @@
+#include <iostream>
+
+#include "utils/command_line/arguments.hpp"
+#include "cypher/common.hpp"
+#include "query_engine.hpp"
+
+using std::cout;
+using std::endl;
+
+int main(int argc, char** argv)
+{   
+    // arguments parsing
+    auto arguments = all_arguments(argc, argv);
+
+    // query extraction
+    auto cypher_query = extract_query(arguments);
+    cout << "QUERY: " << cypher_query << endl;
+
+    QueryEngine engine;
+    engine.execute(cypher_query);
+
+    return 0;
+}

query_engine/query_engine.hpp

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <iostream>
+
+#include "query_traverser.hpp"
+#include "code_generator.hpp"
+#include "code_compiler.hpp"
+#include "query_executor.hpp"
+#include "query_result.hpp"
+
+using std::cout;
+using std::endl;
+
+//
+// Current arhitecture:
+// query -> traverser -> [generator] -> [compiler] -> executor
+//
+
+class QueryEngine
+{
+public:
+    QueryResult execute(const std::string& query)
+    {
+        cout << "execute: " << query << endl;
+        return QueryResult();
+    }
+
+private:
+    QueryTraverser traverser;
+    CodeGenerator generator;
+    CodeCompiler compiler;
+    QueryExecutor executor;
+};

query_engine/query_executor.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+class QueryExecutor
+{
+};

query_engine/query_result.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+#include <string>
+
+class QueryResult
+{
+public:
+    std::string result;
+};

query_engine/query_traverser.hpp

@@ -0,0 +1,5 @@
+#pragma once
+
+class QueryTraverser
+{
+};