add http service, plan parsing, catalog serialization

Signed-off-by: Alex Chi <[email protected]>

CMakeLists.txt

@@ -139,6 +139,7 @@ set(BUSTUB_THIRD_PARTY_INCLUDE_DIR
         ${PROJECT_SOURCE_DIR}/third_party/argparse/include
         ${PROJECT_SOURCE_DIR}/third_party/cpp_random_distributions
         ${PROJECT_SOURCE_DIR}/third_party/backward-cpp/include
+        ${PROJECT_SOURCE_DIR}/third_party/json/include
 )
 
 include_directories(${BUSTUB_SRC_INCLUDE_DIR} ${BUSTUB_TEST_INCLUDE_DIR} ${BUSTUB_THIRD_PARTY_INCLUDE_DIR})

src/common/bustub_instance.cpp

@@ -251,6 +251,50 @@ auto BustubInstance::ExecuteSql(const std::string &sql, ResultWriter &writer,
   }
 }
 
+auto BustubInstance::ExecutePlan(const AbstractPlanNodeRef &plan, ResultWriter &writer) -> bool {
+  auto txn = txn_manager_->Begin();
+  try {
+    auto result = ExecutePlanTxn(plan, txn, writer);
+    txn_manager_->Commit(txn);
+    delete txn;
+    return result;
+  } catch (bustub::Exception &ex) {
+    txn_manager_->Abort(txn);
+    delete txn;
+    throw ex;
+  }
+}
+
+auto BustubInstance::ExecutePlanTxn(const AbstractPlanNodeRef &plan, Transaction *txn, ResultWriter &writer) -> bool {
+  // Execute the query.
+  auto exec_ctx = MakeExecutorContext(txn, false);
+  std::vector<Tuple> result_set{};
+  auto is_successful = execution_engine_->Execute(plan, &result_set, txn, exec_ctx.get());
+
+  // Return the result set as a vector of string.
+  auto schema = plan->OutputSchema();
+
+  // Generate header for the result set.
+  writer.BeginTable(false);
+  writer.BeginHeader();
+  for (const auto &column : schema.GetColumns()) {
+    writer.WriteHeaderCell(column.GetName());
+  }
+  writer.EndHeader();
+
+  // Transforming result set into strings.
+  for (const auto &tuple : result_set) {
+    writer.BeginRow();
+    for (uint32_t i = 0; i < schema.GetColumnCount(); i++) {
+      writer.WriteCell(tuple.GetValue(&schema, i).ToString());
+    }
+    writer.EndRow();
+  }
+  writer.EndTable();
+
+  return is_successful;
+}
+
 auto BustubInstance::ExecuteSqlTxn(const std::string &sql, ResultWriter &writer, Transaction *txn,
                                    std::shared_ptr<CheckOptions> check_options) -> bool {
   if (!sql.empty() && sql[0] == '\\') {

src/include/common/bustub_instance.h

@@ -26,6 +26,7 @@
 #include "common/config.h"
 #include "common/util/string_util.h"
 #include "execution/check_options.h"
+#include "execution/plans/abstract_plan.h"
 #include "libfort/lib/fort.hpp"
 #include "type/value.h"
 
@@ -265,6 +266,9 @@ class BustubInstance {
   /** Get the current transaction. */
   auto CurrentManagedTxn() -> Transaction *;
 
+  auto ExecutePlan(const AbstractPlanNodeRef &plan, ResultWriter &writer) -> bool;
+  auto ExecutePlanTxn(const AbstractPlanNodeRef &plan, Transaction *txn, ResultWriter &writer) -> bool;
+
   /**
    * FOR TEST ONLY. Generate test tables in this BusTub instance.
    * It's used in the shell to predefine some tables, as we don't support

third_party/CMakeLists.txt

@@ -17,3 +17,7 @@ add_subdirectory(utf8proc)
 add_subdirectory(backward-cpp)
 
 add_subdirectory(readerwriterqueue)
+
+add_subdirectory(json)
+
+add_subdirectory(cpp-httplib)

tools/CMakeLists.txt

@@ -8,6 +8,7 @@ add_subdirectory(terrier_bench)
 add_subdirectory(bpm_bench)
 add_subdirectory(btree_bench)
 add_subdirectory(htable_bench)
+add_subdirectory(http-server)
 
 add_backward(shell)
 add_backward(nc-shell)

tools/http-server/CMakeLists.txt

@@ -0,0 +1,5 @@
+set(HTTP_SERVER_SOURCES http-server.cpp)
+add_executable(http-server ${HTTP_SERVER_SOURCES})
+
+target_link_libraries(http-server bustub)
+set_target_properties(http-server PROPERTIES OUTPUT_NAME bustub-http-server)

tools/http-server/http-server.cpp

@@ -0,0 +1,205 @@
+#include <iostream>
+#include <memory>
+#include <nlohmann/json.hpp>
+#include <sstream>
+#include <string>
+#include <vector>
+#include "binder/table_ref/bound_join_ref.h"
+#include "catalog/column.h"
+#include "catalog/schema.h"
+#include "common/bustub_instance.h"
+#include "common/exception.h"
+#include "cpp-httplib/httplib.h"
+#include "execution/expressions/abstract_expression.h"
+#include "execution/expressions/column_value_expression.h"
+#include "execution/expressions/comparison_expression.h"
+#include "execution/plans/abstract_plan.h"
+#include "execution/plans/nested_loop_join_plan.h"
+#include "execution/plans/projection_plan.h"
+#include "execution/plans/seq_scan_plan.h"
+#include "type/type.h"
+#include "type/type_id.h"
+
+using json = nlohmann::json;
+
+auto TransformType(const std::string &ft) -> bustub::TypeId {
+  if (ft == "INTEGER") {
+    return bustub::TypeId::INTEGER;
+  }
+  if (ft == "BOOLEAN") {
+    return bustub::TypeId::BOOLEAN;
+  }
+  throw bustub::Exception("unsupported field type");
+}
+
+auto TransformExpr(json expr, const std::vector<bustub::AbstractPlanNodeRef> &children)
+    -> bustub::AbstractExpressionRef {
+  bustub::TypeId out_type = TransformType(expr["outType"]);
+  if (expr.contains("op")) {
+    json op = expr["op"];
+    std::string name = op["name"];
+    std::vector<json> operands_json = expr["operands"];
+    std::vector<bustub::AbstractExpressionRef> operands;
+    operands.reserve(operands_json.size());
+    for (const auto &operand_json : operands_json) {
+      operands.emplace_back(TransformExpr(operand_json, children));
+    }
+    if (name == "=") {
+      return std::make_shared<bustub::ComparisonExpression>(operands[0], operands[1], bustub::ComparisonType::Equal);
+    }
+    throw bustub::Exception("unsupported op");
+  }
+
+  // column value expression
+  std::string name = expr["name"];
+  size_t input = expr["input"];
+  size_t i = 0;
+  for (; i < children.size(); i++) {
+    size_t cnt = children[i]->OutputSchema().GetColumnCount();
+    if (input < cnt) {
+      break;
+    }
+    input -= cnt;
+  }
+  return std::make_shared<bustub::ColumnValueExpression>(i, input, out_type);
+}
+
+auto TransformRootRel(bustub::BustubInstance &bustub, const std::map<std::string, json> &rels, json root_rel)
+    -> bustub::AbstractPlanNodeRef {
+  std::string rel_op = root_rel["relOp"];
+  std::vector<std::string> inputs = root_rel["inputs"];
+  std::vector<bustub::AbstractPlanNodeRef> input_plan_nodes;
+  for (const auto &input : inputs) {
+    auto input_rel = rels.find(input)->second;
+    auto input_plan_node = TransformRootRel(bustub, rels, input_rel);
+    input_plan_nodes.emplace_back(std::move(input_plan_node));
+  }
+  std::vector<std::string> fields = root_rel["fields"];
+  std::vector<std::string> field_types = root_rel["fieldTypes"];
+  std::vector<bustub::Column> columns;
+  for (size_t i = 0; i < fields.size(); i++) {
+    auto ft = field_types[i];
+    columns.emplace_back(fields[i], TransformType(ft));
+  }
+  bustub::SchemaRef schema = std::make_shared<bustub::Schema>(columns);
+  if (rel_op == "org.apache.calcite.interpreter.Bindables$BindableJoin") {
+    std::string join_type = root_rel["joinType"];
+    bustub::JoinType jt;
+    if (join_type == "inner") {
+      jt = bustub::JoinType::INNER;
+    } else {
+      throw bustub::Exception("unsupported join type");
+    }
+    auto predicate = TransformExpr(root_rel["condition"], input_plan_nodes);
+    return std::make_shared<bustub::NestedLoopJoinPlanNode>(std::move(schema), input_plan_nodes[0], input_plan_nodes[1],
+                                                            predicate, jt);
+  }
+  if (rel_op == "org.apache.calcite.interpreter.Bindables$BindableTableScan") {
+    std::string table_name = root_rel["table"][0];
+    auto table_info = bustub.catalog_->GetTable(table_name);
+    return std::make_shared<bustub::SeqScanPlanNode>(std::move(schema), table_info->oid_, table_name);
+  }
+  if (rel_op == "org.apache.calcite.interpreter.Bindables$BindableProject") {
+    std::vector<bustub::AbstractExpressionRef> exprs;
+    std::vector<json> exprs_json = root_rel["exprs"];
+    exprs.reserve(exprs_json.size());
+    for (const auto &expr_json : exprs_json) {
+      exprs.emplace_back(TransformExpr(expr_json, input_plan_nodes));
+    }
+    return std::make_shared<bustub::ProjectionPlanNode>(std::move(schema), exprs, input_plan_nodes[0]);
+  }
+  throw bustub::Exception("unsupported rel type");
+}
+
+auto BuildPlanNodeFromJson(bustub::BustubInstance &bustub, json plan) -> bustub::AbstractPlanNodeRef {
+  std::map<std::string, json> rels;
+  std::vector<json> json_rels = plan["rels"];
+  for (const auto &rel : json_rels) {
+    rels[rel["id"]] = rel;
+  }
+  json root_rel = *json_rels.rbegin();
+  return TransformRootRel(bustub, rels, root_rel);
+}
+
+// NOLINTNEXTLINE
+auto main(int argc, char **argv) -> int {
+  auto bustub = std::make_unique<bustub::BustubInstance>();
+
+  // HTTP
+  httplib::Server svr;
+
+  svr.set_exception_handler([](const auto &req, auto &res, std::exception_ptr ep) {
+    std::string exception;
+    try {
+      std::rethrow_exception(ep);
+    } catch (bustub::Exception &e) {
+      exception = e.what();
+    } catch (std::exception &e) {
+      exception = e.what();
+    } catch (...) {  // See the following NOTE
+      exception = "unknown exception";
+    }
+    res.set_content(exception, "text/plain");
+    res.status = 500;
+  });
+
+  svr.Post("/sql", [&bustub](const httplib::Request &req, httplib::Response &res) {
+    std::stringstream ss;
+    bustub::SimpleStreamWriter writer(ss, false);
+    json data = json::parse(req.body);
+    std::cerr << "SQL request: " << data["sql"] << std::endl;
+    bustub->ExecuteSql(data["sql"], writer);
+    res.set_content(ss.str(), "text/plain");
+  });
+
+  svr.Post("/plan", [&bustub](const httplib::Request &req, httplib::Response &res) {
+    std::stringstream ss;
+    bustub::SimpleStreamWriter writer(ss, false);
+    std::cerr << "Plan request:";
+    json json_plan = json::parse(req.body);
+    std::cerr << json_plan << std::endl;
+    auto plan = BuildPlanNodeFromJson(*bustub, json_plan);
+    std::cerr << "BusTub plan:" << std::endl << plan->ToString(true) << std::endl;
+    bustub->ExecutePlan(plan, writer);
+    res.set_content(ss.str(), "text/plain");
+  });
+
+  svr.Get("/catalog", [&bustub](const httplib::Request &req, httplib::Response &res) {
+    std::cerr << "Catalog request" << std::endl;
+    auto tables = bustub->catalog_->GetTableNames();
+    std::vector<json> catalog;
+    for (const auto &tbl_name : tables) {
+      auto table = bustub->catalog_->GetTable(tbl_name);
+      std::vector<json> schema;
+      for (size_t c = 0; c < table->schema_.GetColumnCount(); c++) {
+        auto col = table->schema_.GetColumn(c);
+        switch (col.GetType()) {
+          case bustub::TypeId::BIGINT: {
+            schema.emplace_back(std::map<std::string, std::string>{{"name", col.GetName()}, {"type", "bigint"}});
+            break;
+          }
+          case bustub::TypeId::INTEGER: {
+            schema.emplace_back(std::map<std::string, std::string>{{"name", col.GetName()}, {"type", "integer"}});
+            break;
+          }
+          case bustub::TypeId::VARCHAR: {
+            schema.emplace_back(std::map<std::string, std::string>{{"name", col.GetName()}, {"type", "varchar"}});
+            break;
+          }
+          default:
+            throw bustub::Exception("unsupported column type");
+        }
+      }
+      catalog.emplace_back(std::map<std::string, json>{{std::string("name"), json(table->name_)},
+                                                       {std::string("oid"), json(table->oid_)},
+                                                       {std::string("schema"), json(schema)}});
+    }
+    res.set_content(json(std::map<std::string, json>{{"catalog", catalog}}).dump(), "text/plain");
+  });
+
+  std::cerr << "BusTub HTTP server listening" << std::endl;
+
+  svr.listen("127.0.0.1", 23333);
+
+  return 0;
+}