feat: add hash command hexists

src/base_cmd.h

@@ -85,6 +85,7 @@ const std::string kCmdNameHIncrbyFloat = "hincrbyfloat";
 const std::string kCmdNameHSetNX = "hsetnx";
 const std::string kCmdNameHIncrby = "hincrby";
 const std::string kCmdNameHRandField = "hrandfield";
+const std::string kCmdNameHExists = "hexists";
 
 // set cmd
 const std::string kCmdNameSIsMember = "sismember";

src/cmd_hash.cc

@@ -455,4 +455,27 @@ void HRandFieldCmd::DoCmd(PClient* client) {
   }
 }
 
+HExistsCmd::HExistsCmd(const std::string& name, int16_t arity)
+    : BaseCmd(name, arity, kCmdFlagsReadonly, kAclCategoryRead | kAclCategoryHash) {}
+
+bool HExistsCmd::DoInitial(PClient* client) {
+  client->SetKey(client->argv_[1]);
+  return true;
+}
+
+void HExistsCmd::DoCmd(PClient* client) {
+  // parse arguments
+  auto& field = client->argv_[2];
+
+  // execute command
+  std::vector<std::string> res;
+  auto s = PSTORE.GetBackend(client->GetCurrentDB())->GetStorage()->HExists(client->Key(), field);
+  if (!s.ok() && !s.IsNotFound()) {
+    return client->SetRes(CmdRes::kErrOther, s.ToString());
+  }
+
+  // reply
+  client->AppendInteger(s.IsNotFound() ? 0 : 1);
+}
+
 }  // namespace pikiwidb

src/cmd_hash.h

@@ -181,4 +181,15 @@ class HRandFieldCmd : public BaseCmd {
   static constexpr std::string_view kWithValueString = "withvalues";
 };
 
+class HExistsCmd : public BaseCmd {
+ public:
+  HExistsCmd(const std::string &name, int16_t arity);
+
+ protected:
+  bool DoInitial(PClient *client) override;
+
+ private:
+  void DoCmd(PClient *client) override;
+};
+
 }  // namespace pikiwidb

src/cmd_table_manager.cc

@@ -92,6 +92,7 @@ void CmdTableManager::InitCmdTable() {
   ADD_COMMAND(HSetNX, 4);
   ADD_COMMAND(HIncrby, 4);
   ADD_COMMAND(HRandField, -2);
+  ADD_COMMAND(HExists, 3);
 
   // set
   ADD_COMMAND(SIsMember, 3);

tests/hash_test.go

@@ -229,7 +229,7 @@ var _ = Describe("Hash", Ordered, func() {
 		hGet := client.HGet(ctx, "hash", "key")
 		Expect(hGet.Err()).NotTo(HaveOccurred())
 		Expect(hGet.Val()).To(Equal("hello"))
-  })
+	})
 
 	It("should HIncrBy", func() {
 		hSet := client.HSet(ctx, "hash", "key", "5")
@@ -331,4 +331,17 @@ var _ = Describe("Hash", Ordered, func() {
 		res1 := client.HRandField(ctx, "not_exist_key", 1).Val()
 		Expect(len(res1)).To(Equal(0))
 	})
+
+	It("should HExists", func() {
+		hSet := client.HSet(ctx, "hash", "key", "hello")
+		Expect(hSet.Err()).NotTo(HaveOccurred())
+
+		hExists := client.HExists(ctx, "hash", "key")
+		Expect(hExists.Err()).NotTo(HaveOccurred())
+		Expect(hExists.Val()).To(Equal(true))
+
+		hExists = client.HExists(ctx, "hash", "key1")
+		Expect(hExists.Err()).NotTo(HaveOccurred())
+		Expect(hExists.Val()).To(Equal(false))
+	})
 })