added room implementation

app/src/main/java/com/edrees/newsapp/dao/ArticleDao.kt

@@ -0,0 +1,13 @@
+package com.edrees.newsapp.dao
+
+import androidx.room.Dao
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import com.edrees.newsapp.model.Article
+
+@Dao
+interface ArticleDao {
+    @Insert(onConflict = OnConflictStrategy.IGNORE)
+    suspend fun insertArticle(vararg articles: Article)
+}

app/src/main/java/com/edrees/newsapp/db/NewsDatabase.kt

@@ -0,0 +1,25 @@
+package com.edrees.newsapp.db
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import com.edrees.newsapp.dao.ArticleDao
+import com.edrees.newsapp.model.Article
+
+@Database(entities = [Article::class], version = 1)
+abstract class NewsDatabase : RoomDatabase(){
+    abstract fun articleDao(): ArticleDao
+    companion object{
+        @Volatile
+        private var INSTANCE: NewsDatabase? = null
+        fun getInstance(context: Context): NewsDatabase{
+            return INSTANCE?: synchronized(this){
+                INSTANCE?: Room.databaseBuilder(context, NewsDatabase::class.java, "news_db")
+                    .fallbackToDestructiveMigration()
+                    .build()
+                    .also { INSTANCE = it}
+            }
+        }
+    }
+}

app/src/main/java/com/edrees/newsapp/model/Article.kt

@@ -1,12 +1,17 @@
 package com.edrees.newsapp.model
 
+import androidx.room.ColumnInfo
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity("articles")
 data class Article(
     val author: String,
     val content: String,
     val description: String,
-    val publishedAt: String,
+    @ColumnInfo(name="puplished_at")val publishedAt: String,
     val source: Source,
     val title: String,
-    val url: String,
-    val urlToImage: String
+    @PrimaryKey val url: String,
+    @ColumnInfo(name="url_to_image")val urlToImage: String
 )