feat(search): add a value type system to KQIR

src/commands/cmd_search.cc

@@ -150,7 +150,7 @@ static void DumpQueryResult(const std::vector<kqir::ExecutorContext::RowType> &r
     output->append(MultiLen(fields.size() * 2));
     for (const auto &[info, field] : fields) {
       output->append(redis::BulkString(info->name));
-      output->append(redis::BulkString(field));
+      output->append(redis::BulkString(field.ToString(info->metadata.get())));
     }
   }
 }

src/common/string_util.h

@@ -42,7 +42,7 @@ std::string StringNext(std::string s);
 
 template <typename T, typename F>
 std::string StringJoin(
-    const T &con, F &&f = [](const auto &v) -> decltype(auto) { return v; }, const std::string &sep = ", ") {
+    const T &con, F &&f = [](const auto &v) -> decltype(auto) { return v; }, std::string_view sep = ", ") {
   std::string res;
   bool is_first = true;
   for (const auto &v : con) {

src/search/common_parser.h

@@ -42,7 +42,7 @@ struct UnescapedChar : peg::utf8::range<0x20, 0x10FFFF> {};
 struct Char : peg::if_then_else<peg::one<'\\'>, EscapedChar, UnescapedChar> {};
 
 struct StringContent : peg::until<peg::at<peg::one<'"'>>, Char> {};
-struct String : peg::seq<peg::one<'"'>, StringContent, peg::any> {};
+struct StringL : peg::seq<peg::one<'"'>, StringContent, peg::any> {};
 
 struct Identifier : peg::identifier {};
 

src/search/executors/filter_executor.h

@@ -74,17 +74,17 @@ struct QueryExprEvaluator {
 
   StatusOr<bool> Visit(TagContainExpr *v) const {
     auto val = GET_OR_RET(ctx->Retrieve(row, v->field->info));
-    auto meta = v->field->info->MetadataAs<redis::TagFieldMetadata>();
 
-    auto split = util::Split(val, std::string(1, meta->separator));
+    CHECK(val.Is<kqir::StringArray>());
+    auto split = val.Get<kqir::StringArray>();
     return std::find(split.begin(), split.end(), v->tag->val) != split.end();
   }
 
   StatusOr<bool> Visit(NumericCompareExpr *v) const {
-    auto l_str = GET_OR_RET(ctx->Retrieve(row, v->field->info));
+    auto l_val = GET_OR_RET(ctx->Retrieve(row, v->field->info));
 
-    // TODO: reconsider how to handle failure case here
-    auto l = GET_OR_RET(ParseFloat(l_str));
+    CHECK(l_val.Is<kqir::Numeric>());
+    auto l = l_val.Get<kqir::Numeric>();
     auto r = v->num->val;
 
     switch (v->op) {

src/search/executors/numeric_field_scan_executor.h

@@ -26,6 +26,7 @@
 #include "encoding.h"
 #include "search/plan_executor.h"
 #include "search/search_encoding.h"
+#include "search/value.h"
 #include "storage/redis_db.h"
 #include "storage/redis_metadata.h"
 #include "storage/storage.h"
@@ -108,7 +109,7 @@ struct NumericFieldScanExecutor : ExecutorNode {
     } else {
       iter->Prev();
     }
-    return RowType{key_str, {{scan->field->info, std::to_string(curr)}}, scan->field->info->index};
+    return RowType{key_str, {{scan->field->info, kqir::MakeValue<kqir::Numeric>(curr)}}, scan->field->info->index};
   }
 };
 

src/search/executors/topn_sort_executor.h

@@ -57,9 +57,9 @@ struct TopNSortExecutor : ExecutorNode {
         auto &row = std::get<RowType>(v);
 
         auto get_order = [this](RowType &row) -> StatusOr<double> {
-          auto order_str = GET_OR_RET(ctx->Retrieve(row, sort->order->field->info));
-          auto order = GET_OR_RET(ParseFloat(order_str));
-          return order;
+          auto order_val = GET_OR_RET(ctx->Retrieve(row, sort->order->field->info));
+          CHECK(order_val.Is<kqir::Numeric>());
+          return order_val.Get<kqir::Numeric>();
         };
 
         if (rows.size() == total) {

src/search/indexer.cc

@@ -26,6 +26,7 @@
 #include "db_util.h"
 #include "parse_util.h"
 #include "search/search_encoding.h"
+#include "search/value.h"
 #include "storage/redis_metadata.h"
 #include "storage/storage.h"
 #include "string_util.h"
@@ -56,25 +57,67 @@ StatusOr<FieldValueRetriever> FieldValueRetriever::Create(IndexOnDataType type,
   }
 }
 
-rocksdb::Status FieldValueRetriever::Retrieve(std::string_view field, std::string *output) {
+StatusOr<kqir::Value> FieldValueRetriever::Retrieve(std::string_view field, const redis::IndexFieldMetadata *type) {
   if (std::holds_alternative<HashData>(db)) {
     auto &[hash, metadata, key] = std::get<HashData>(db);
     std::string ns_key = hash.AppendNamespacePrefix(key);
+
     LatestSnapShot ss(hash.storage_);
     rocksdb::ReadOptions read_options;
     read_options.snapshot = ss.GetSnapShot();
     std::string sub_key = InternalKey(ns_key, field, metadata.version, hash.storage_->IsSlotIdEncoded()).Encode();
-    return hash.storage_->Get(read_options, sub_key, output);
+    std::string value;
+    auto s = hash.storage_->Get(read_options, sub_key, &value);
+    if (s.IsNotFound()) return {Status::NotFound, s.ToString()};
+    if (!s.ok()) return {Status::NotOK, s.ToString()};
+
+    if (auto numeric [[maybe_unused]] = dynamic_cast<const redis::NumericFieldMetadata *>(type)) {
+      auto num = GET_OR_RET(ParseFloat(value));
+      return kqir::MakeValue<kqir::Numeric>(num);
+    } else if (auto tag = dynamic_cast<const redis::TagFieldMetadata *>(type)) {
+      const char delim[] = {tag->separator, '\0'};
+      auto vec = util::Split(value, delim);
+      return kqir::MakeValue<kqir::StringArray>(vec);
+    } else {
+      return {Status::NotOK, "unknown field type to retrieve"};
+    }
+
   } else if (std::holds_alternative<JsonData>(db)) {
     auto &value = std::get<JsonData>(db);
+
     auto s = value.Get(field.front() == '$' ? field : fmt::format("$.{}", field));
-    if (!s.IsOK()) return rocksdb::Status::Corruption(s.Msg());
+    if (!s.IsOK()) return {Status::NotOK, s.Msg()};
     if (s->value.size() != 1)
-      return rocksdb::Status::NotFound("json value specified by the field (json path) should exist and be unique");
-    *output = s->value[0].as_string();
-    return rocksdb::Status::OK();
+      return {Status::NotFound, "json value specified by the field (json path) should exist and be unique"};
+    auto val = s->value[0];
+
+    if (auto numeric [[maybe_unused]] = dynamic_cast<const redis::NumericFieldMetadata *>(type)) {
+      if (val.is_string()) return {Status::NotOK, "json value cannot be string for numeric fields"};
+      return kqir::MakeValue<kqir::Numeric>(val.as_double());
+    } else if (auto tag = dynamic_cast<const redis::TagFieldMetadata *>(type)) {
+      if (val.is_string()) {
+        const char delim[] = {tag->separator, '\0'};
+        auto vec = util::Split(val.as_string(), delim);
+        return kqir::MakeValue<kqir::StringArray>(vec);
+      } else if (val.is_array()) {
+        std::vector<std::string> strs;
+        for (size_t i = 0; i < val.size(); ++i) {
+          if (!val[i].is_string())
+            return {Status::NotOK, "json value should be string or array of strings for tag fields"};
+          strs.push_back(val[i].as_string());
+        }
+        return kqir::MakeValue<kqir::StringArray>(strs);
+      } else {
+        return {Status::NotOK, "json value should be string or array of strings for tag fields"};
+      }
+    } else {
+      return {Status::NotOK, "unknown field type to retrieve"};
+    }
+
+    return Status::OK();
+
   } else {
-    __builtin_unreachable();
+    return {Status::NotOK, "unknown redis data type to retrieve"};
   }
 }
 
@@ -102,22 +145,22 @@ StatusOr<IndexUpdater::FieldValues> IndexUpdater::Record(std::string_view key) c
       continue;
     }
 
-    std::string value;
-    auto s = retriever.Retrieve(field, &value);
-    if (s.IsNotFound()) continue;
-    if (!s.ok()) return {Status::NotOK, s.ToString()};
+    auto s = retriever.Retrieve(field, i.metadata.get());
+    if (s.Is<Status::NotFound>()) continue;
+    if (!s) return s;
 
-    values.emplace(field, value);
+    values.emplace(field, *s);
   }
 
   return values;
 }
 
-Status IndexUpdater::UpdateTagIndex(std::string_view key, std::string_view original, std::string_view current,
+Status IndexUpdater::UpdateTagIndex(std::string_view key, const kqir::Value &original, const kqir::Value &current,
                                     const SearchKey &search_key, const TagFieldMetadata *tag) const {
-  const char delim[] = {tag->separator, '\0'};
-  auto original_tags = util::Split(original, delim);
-  auto current_tags = util::Split(current, delim);
+  CHECK(original.IsNull() || original.Is<kqir::StringArray>());
+  CHECK(current.IsNull() || current.Is<kqir::StringArray>());
+  auto original_tags = original.IsNull() ? std::vector<std::string>() : original.Get<kqir::StringArray>();
+  auto current_tags = current.IsNull() ? std::vector<std::string>() : current.Get<kqir::StringArray>();
 
   auto to_tag_set = [](const std::vector<std::string> &tags, bool case_sensitive) -> std::set<std::string> {
     if (case_sensitive) {
@@ -167,22 +210,23 @@ Status IndexUpdater::UpdateTagIndex(std::string_view key, std::string_view origi
   return Status::OK();
 }
 
-Status IndexUpdater::UpdateNumericIndex(std::string_view key, std::string_view original, std::string_view current,
+Status IndexUpdater::UpdateNumericIndex(std::string_view key, const kqir::Value &original, const kqir::Value &current,
                                         const SearchKey &search_key, const NumericFieldMetadata *num) const {
+  CHECK(original.IsNull() || original.Is<kqir::Numeric>());
+  CHECK(original.IsNull() || original.Is<kqir::Numeric>());
+
   auto *storage = indexer->storage;
   auto batch = storage->GetWriteBatchBase();
   auto cf_handle = storage->GetCFHandle(ColumnFamilyID::Search);
 
-  if (!original.empty()) {
-    auto original_num = GET_OR_RET(ParseFloat(std::string(original.begin(), original.end())));
-    auto index_key = search_key.ConstructNumericFieldData(original_num, key);
+  if (!original.IsNull()) {
+    auto index_key = search_key.ConstructNumericFieldData(original.Get<kqir::Numeric>(), key);
 
     batch->Delete(cf_handle, index_key);
   }
 
-  if (!current.empty()) {
-    auto current_num = GET_OR_RET(ParseFloat(std::string(current.begin(), current.end())));
-    auto index_key = search_key.ConstructNumericFieldData(current_num, key);
+  if (!current.IsNull()) {
+    auto index_key = search_key.ConstructNumericFieldData(current.Get<kqir::Numeric>(), key);
 
     batch->Put(cf_handle, index_key, Slice());
   }
@@ -192,8 +236,8 @@ Status IndexUpdater::UpdateNumericIndex(std::string_view key, std::string_view o
   return Status::OK();
 }
 
-Status IndexUpdater::UpdateIndex(const std::string &field, std::string_view key, std::string_view original,
-                                 std::string_view current) const {
+Status IndexUpdater::UpdateIndex(const std::string &field, std::string_view key, const kqir::Value &original,
+                                 const kqir::Value &current) const {
   if (original == current) {
     // the value of this field is unchanged, no need to update
     return Status::OK();
@@ -225,7 +269,7 @@ Status IndexUpdater::Update(const FieldValues &original, std::string_view key) c
       continue;
     }
 
-    std::string_view original_val, current_val;
+    kqir::Value original_val, current_val;
 
     if (auto it = original.find(field); it != original.end()) {
       original_val = it->second;

src/search/indexer.h

@@ -36,6 +36,7 @@
 #include "storage/storage.h"
 #include "types/redis_hash.h"
 #include "types/redis_json.h"
+#include "value.h"
 
 namespace redis {
 
@@ -63,27 +64,27 @@ struct FieldValueRetriever {
 
   explicit FieldValueRetriever(JsonValue json) : db(std::in_place_type<JsonData>, std::move(json)) {}
 
-  rocksdb::Status Retrieve(std::string_view field, std::string *output);
+  StatusOr<kqir::Value> Retrieve(std::string_view field, const redis::IndexFieldMetadata *type);
 };
 
 struct IndexUpdater {
-  using FieldValues = std::map<std::string, std::string>;
+  using FieldValues = std::map<std::string, kqir::Value>;
 
   const kqir::IndexInfo *info = nullptr;
   GlobalIndexer *indexer = nullptr;
 
   explicit IndexUpdater(const kqir::IndexInfo *info) : info(info) {}
 
   StatusOr<FieldValues> Record(std::string_view key) const;
-  Status UpdateIndex(const std::string &field, std::string_view key, std::string_view original,
-                     std::string_view current) const;
+  Status UpdateIndex(const std::string &field, std::string_view key, const kqir::Value &original,
+                     const kqir::Value &current) const;
   Status Update(const FieldValues &original, std::string_view key) const;
 
   Status Build() const;
 
-  Status UpdateTagIndex(std::string_view key, std::string_view original, std::string_view current,
+  Status UpdateTagIndex(std::string_view key, const kqir::Value &original, const kqir::Value &current,
                         const SearchKey &search_key, const TagFieldMetadata *tag) const;
-  Status UpdateNumericIndex(std::string_view key, std::string_view original, std::string_view current,
+  Status UpdateNumericIndex(std::string_view key, const kqir::Value &original, const kqir::Value &current,
                             const SearchKey &search_key, const NumericFieldMetadata *num) const;
 };
 

src/search/ir.h

@@ -38,7 +38,7 @@
 #include "string_util.h"
 #include "type_util.h"
 
-// kqir stands for Kvorcks Query Intermediate Representation
+// kqir stands for Kvrocks Query Intermediate Representation
 namespace kqir {
 
 struct Node {

src/search/plan_executor.cc

@@ -152,12 +152,11 @@ auto ExecutorContext::Retrieve(RowType &row, const FieldInfo *field) -> StatusOr
   auto retriever = GET_OR_RET(
       redis::FieldValueRetriever::Create(field->index->metadata.on_data_type, row.key, storage, field->index->ns));
 
-  std::string result;
-  auto s = retriever.Retrieve(field->name, &result);
-  if (!s.ok()) return {Status::NotOK, s.ToString()};
+  auto s = retriever.Retrieve(field->name, field->metadata.get());
+  if (!s) return s;
 
-  row.fields.emplace(field, result);
-  return result;
+  row.fields.emplace(field, *s);
+  return *s;
 }
 
 }  // namespace kqir

src/search/plan_executor.h

@@ -24,6 +24,7 @@
 
 #include "ir_plan.h"
 #include "search/index_info.h"
+#include "search/value.h"
 #include "storage/storage.h"
 #include "string_util.h"
 
@@ -33,7 +34,7 @@ struct ExecutorContext;
 
 struct ExecutorNode {
   using KeyType = std::string;
-  using ValueType = std::string;
+  using ValueType = kqir::Value;
   struct RowType {
     KeyType key;
     std::map<const FieldInfo *, ValueType> fields;
@@ -52,8 +53,9 @@ struct ExecutorNode {
       } else {
         os << row.key;
       }
-      return os << " {" << util::StringJoin(row.fields, [](const auto &v) { return v.first->name + ": " + v.second; })
-                << "}";
+      return os << " {" << util::StringJoin(row.fields, [](const auto &v) {
+               return v.first->name + ": " + v.second.ToString();
+             }) << "}";
     }
   };
 

src/search/redis_query_parser.h

@@ -32,7 +32,7 @@ using namespace peg;
 
 struct Field : seq<one<'@'>, Identifier> {};
 
-struct Tag : sor<Identifier, String> {};
+struct Tag : sor<Identifier, StringL> {};
 struct TagList : seq<one<'{'>, WSPad<Tag>, star<seq<one<'|'>, WSPad<Tag>>>, one<'}'>> {};
 
 struct Inf : seq<opt<one<'+', '-'>>, string<'i', 'n', 'f'>> {};

src/search/redis_query_transformer.h

@@ -36,7 +36,7 @@ namespace ir = kqir;
 
 template <typename Rule>
 using TreeSelector =
-    parse_tree::selector<Rule, parse_tree::store_content::on<Number, String, Identifier, Inf>,
+    parse_tree::selector<Rule, parse_tree::store_content::on<Number, StringL, Identifier, Inf>,
                          parse_tree::remove_content::on<TagList, NumericRange, ExclusiveNumber, FieldQuery, NotExpr,
                                                         AndExpr, OrExpr, Wildcard>>;
 

src/search/sql_parser.h

@@ -31,7 +31,7 @@ namespace sql {
 using namespace peg;
 
 struct HasTag : string<'h', 'a', 's', 't', 'a', 'g'> {};
-struct HasTagExpr : WSPad<seq<Identifier, WSPad<HasTag>, String>> {};
+struct HasTagExpr : WSPad<seq<Identifier, WSPad<HasTag>, StringL>> {};
 
 struct NumericAtomExpr : WSPad<sor<Number, Identifier>> {};
 struct NumericCompareOp : sor<string<'!', '='>, string<'<', '='>, string<'>', '='>, one<'=', '<', '>'>> {};

src/search/sql_transformer.h

@@ -38,7 +38,7 @@ namespace ir = kqir;
 template <typename Rule>
 using TreeSelector = parse_tree::selector<
     Rule,
-    parse_tree::store_content::on<Boolean, Number, String, Identifier, NumericCompareOp, AscOrDesc, UnsignedInteger>,
+    parse_tree::store_content::on<Boolean, Number, StringL, Identifier, NumericCompareOp, AscOrDesc, UnsignedInteger>,
     parse_tree::remove_content::on<HasTagExpr, NumericCompareExpr, NotExpr, AndExpr, OrExpr, Wildcard, SelectExpr,
                                    FromExpr, WhereClause, OrderByClause, LimitClause, SearchStmt>>;
 
@@ -58,7 +58,7 @@ struct Transformer : ir::TreeTransformer {
       return Node::Create<ir::BoolLiteral>(node->string_view() == "true");
     } else if (Is<Number>(node)) {
       return Node::Create<ir::NumericLiteral>(*ParseFloat(node->string()));
-    } else if (Is<String>(node)) {
+    } else if (Is<StringL>(node)) {
       return Node::Create<ir::StringLiteral>(GET_OR_RET(UnescapeString(node->string_view())));
     } else if (Is<HasTagExpr>(node)) {
       CHECK(node->children.size() == 2);