From 250f9339b1e9c60dcb5c5e2256645ce14995400d Mon Sep 17 00:00:00 2001
From: Otavio Santana <otaviopolianasantana@gmail.com>
Date: Wed, 29 Nov 2023 05:57:19 +0000
Subject: [PATCH] feat: create json mapper

Signed-off-by: Otavio Santana <otaviopolianasantana@gmail.com>
---
 .../java/expert/os/harperdb/JSONMapper.java   | 18 ++++++++++++++++--
 .../main/java/expert/os/harperdb/Server.java  | 19 +++++++++++++++++++
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/core/src/main/java/expert/os/harperdb/JSONMapper.java b/core/src/main/java/expert/os/harperdb/JSONMapper.java
index 76e8ed5..f1aaf25 100644
--- a/core/src/main/java/expert/os/harperdb/JSONMapper.java
+++ b/core/src/main/java/expert/os/harperdb/JSONMapper.java
@@ -1,11 +1,14 @@
 package expert.os.harperdb;
 
 import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
 
 import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
 import java.util.Optional;
 
 enum JSONMapper {
@@ -26,12 +29,23 @@ byte[] writeValueAsBytes(Object value) {
         }
     }
 
-    <T> Optional<T> readSingleValue(byte[] bytes, Class<T> valueType) {
+    <T> Optional<T> readSingleValue(byte[] bytes, Class<T> type) {
         try {
             if(bytes == null || bytes.length == 0){
                 return Optional.empty();
             }
-            return Optional.of(mapper.readValue(bytes, valueType));
+            return Optional.of(mapper.readValue(bytes, type));
+        } catch (IOException exception) {
+            throw new HarperDBException("There is an issue to read from json value", exception);
+        }
+    }
+
+    <T> List<T> readValue(byte[] bytes, Class<T> type) {
+        try {
+            if(bytes == null || bytes.length == 0){
+                return Collections.emptyList();
+            }
+            return mapper.readValue(bytes, new TypeReference<>() {});
         } catch (IOException exception) {
             throw new HarperDBException("There is an issue to read from json value", exception);
         }
diff --git a/core/src/main/java/expert/os/harperdb/Server.java b/core/src/main/java/expert/os/harperdb/Server.java
index a053082..1923cb9 100644
--- a/core/src/main/java/expert/os/harperdb/Server.java
+++ b/core/src/main/java/expert/os/harperdb/Server.java
@@ -5,6 +5,8 @@
 import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
+import java.util.Collections;
+import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
 
@@ -105,6 +107,23 @@ <T> Optional<T> singleResult(Operation operation, Class<T> type){
         }
     }
 
+    <T> List<T> result(Operation operation, Class<T> type){
+        HttpRequest request = createRequest()
+                .POST(ofByteArray(INSTANCE.writeValueAsBytes(operation)))
+                .build();
+        try {
+            HttpResponse<byte[]> response = client.send(request, HttpResponse.BodyHandlers.ofByteArray());
+            if(HttpStatus.OK.isEquals(response)){
+                byte[] body = response.body();
+                return INSTANCE.readValue(body, type);
+            } else {
+                return Collections.emptyList();
+            }
+        } catch (IOException| InterruptedException e) {
+            throw new HarperDBException("There is an issue to execute the operation: " + operation + "message: ", e);
+        }
+    }
+
 
     HttpRequest.Builder createRequest() {
         return HttpRequest.newBuilder()