>上下文：
最近，我决定进行 Swift 服务器端开发，因为我认为 Vapor 框架非常酷。我在实验时有点卡住了，想要一些关于用叶子和蒸汽模板的建议。
在呈现视图方面，我已经多次查看了文档。呈现包含变量的模板化视图需要叶模板的名称和包含变量的响应表示节点对象。
试图用模板和框架本身来制定一个场景(因为这是我最好的学习方式)，我试图模拟博客格式。这是我的类/获取请求：
// MARK: Blog Post Object
final class BlogPost: NodeRepresentable {
var postId: Int
var postTitle: String
var postContent: String
var postPreview: String
func makeNode(context: Context) throws -> Node {
return try Node(node: [
"postId":self.postId,
"postTitle":self.postTitle,
"postContent":self.postContent,
"postPreview":self.postPreview
])
}
init(_ postId: Int, _ postTitle: String, _ postContent: String) {
self.postId = postId
self.postTitle = postTitle
self.postContent = postContent
self.postPreview = postContent.trunc(100)
}
}
// MARK: Blog view request; iterate over blog objects
drop.get("blog") { request in
let result = try drop.database?.driver.raw("SELECT * FROM Posts;")
guard let posts = result?.nodeArray else {
throw Abort.serverError
}
var postCollection = [BlogPost]()
for post in posts {
guard let postId = post["postId"]?.int,
let postTitle = post["postTitle"]?.string,
let postContent = post["postPreview"]?.string else {
throw Abort.serverError
}
let post = BlogPost(postId, postTitle, postContent)
postCollection.append(post)
}
// Pass posts to be tokenized
/* THIS CODE DOESN'T WORK BECAUSE "CANNOT CONVERT VALUE OF TYPE
* '[BLOGPOST]' TO EXPECTED DICTIONARY VALUE OF TYPE "NODE"
* LOOKING FOR THE BEST METHOD TO PASS THIS LIST OF OBJECTS
*/
drop.view.make("blog", [
"posts":postCollection
])
}
这是我blog.leaf文件：
#extend("base")
#export("head") {
<title>Blog</title>
}
#export("body") {
<h1 class="page-header">Blog Posts</h1>
<div class="page-content-container">
#loop(posts, "posts") {
<div class="post-container">
<h3 style="post-title">#(posts["postTitle"])</h3>
<p style="post-preview">#(posts["postPreview"])</h3>
</div>
}
</div>
}
问题：
如您所见，我有点坚持寻找迭代对象并将其属性模板化到叶文件中的最佳方法。有人有什么建议吗？顺便说一下，很抱歉糟糕的编程约定。我在面向对象/协议编程方面相当陌生。
我最终做的是，使Post模型符合模型协议。
import Foundation
import HTTP
import Vapor
// MARK: Post Class
final class Post: Model {
var id: Node?
var title: String
var content: String
var date: Date
var isVisible: Bool
// TODO: Implement truncate extension for String and set preview
// to content truncated to 100 characters
var preview = "placeholder"
var exists: Bool = false
init(title: String, content: String, isVisible: Bool = true) {
self.title = title
self.content = content
self.date = Date()
self.isVisible = isVisible
}
init(node: Node, in context: Context) throws {
let dateInt: Int = try node.extract("date")
let isVisibleInt: Int = try node.extract("isVisible")
id = try node.extract("id")
title = try node.extract("title")
content = try node.extract("content")
date = Date(timeIntervalSinceNow: TimeInterval(dateInt))
isVisible = Bool(isVisibleInt as NSNumber)
exists = false
}
func makeNode(context: Context) throws -> Node {
return try Node(node: [
"id": id,
"title": title,
"content": content,
"date": Int(date.timeIntervalSince1970),
"isVisible": Int(isVisible as NSNumber)
])
}
static func prepare(_ database: Database) throws {
try database.create("Posts") { posts in
posts.id()
posts.string("title", optional: false)
posts.string("content", optional: false)
posts.int("date", optional: false)
posts.int("isVisible", optional: false)
}
}
static func revert(_ database: Database) throws {
try database.delete("posts")
}
}然后返回/创建 Post 对象的实例：
import Vapor
import Foundation
import HTTP
final class BlogController {
func addRoutes(_ drop: Droplet) {
let blogRouter = drop.grouped("blog")
let blogAPIRouter = drop.grouped("api","blog")
blogRouter.get("posts", handler: getPostsView)
blogAPIRouter.get("posts", handler: getPosts)
blogAPIRouter.post("newPost", handler: newPost)
}
// MARK: Get Posts
func getPosts(_ request: Request) throws -> ResponseRepresentable {
let posts = try Post.all().makeNode()
return try JSON(node: [
"Posts":posts
])
}
// Mark: New Post
func newPost(_ request: Request) throws -> ResponseRepresentable {
guard let title = request.data["title"]?.string,
let content = request.data["content"]?.string else {
throw Abort.badRequest
}
var post = Post(title: title, content: content)
try post.save()
return "success"
}
// Mark: Get Posts Rendered
func getPostsView(_ request: Request) throws -> ResponseRepresentable {
return try getPosts(request)
}
}我还不是 Vapor 方面的专家，但我认为您需要使用.makeNode()以便您的postCollection对象转换为稍后可以在模板上使用的内容。
像这样：
drop.view.make("blog", ["posts":postCollection.makeNode()])
func list(_ req: Request) throws -> ResponseRepresentable {
let list = try User.all()
let node = try list.makeNode(in: nil)
let json = try JSON(node: [ "list":node ])
return json
}