PostModel.kt

data class Post(
    @SerializedName("id")
    val id: String,
    @SerializedName("sender")
    val sender: String?,
    @SerializedName("caption")
    val caption: String?,
    @SerializedName("media")
    val media: String?,
    @SerializedName("timestamp")
    val timestamp: Long?
)

object PostDiffUtils : DiffUtil.ItemCallback<Post>() {
    override fun areItemsTheSame(oldItem: Post, newItem: Post): Boolean {
        return oldItem.id == oldItem.id
    }

    override fun areContentsTheSame(oldItem: Post, newItem: Post): Boolean {
        return oldItem == newItem
    }
}

interface PostApiService {
    @GET("/feed")
    fun getFeed(): Call<Response<List<Post>>>
}