1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
This source file is part of the Swift.org open source project
Copyright (c) 2021 Apple Inc. and the Swift project authors
Licensed under Apache License v2.0 with Runtime Library Exception
See https://swift.org/LICENSE.txt for license information
See https://swift.org/CONTRIBUTORS.txt for Swift project authors
*/
#if canImport(NIOHTTP1)
import Foundation
import NIO
import NIOHTTP1
import SwiftDocC
fileprivate extension String {
var fileExtension: String {
return components(separatedBy: ".").last!.lowercased()
}
}
private let imageType: (String) -> String = { name in
switch name.fileExtension {
case "png": return "image/png"
case "jpg", "jpeg": return "image/jpeg"
case "svg": return "image/svg+xml"
case "gif": return "image/gif"
default: return "application/octet-stream"
}
}
/// A model to parse a "Range" HTTP header.
struct RangeHeader {
/// Lower range bound.
let min: Int
/// Upper range bound.
let max: Int
init?(_ string: String) {
guard string.hasPrefix("bytes=") else {
return nil
}
let bounds = string.dropFirst("bytes=".count).split(separator: "-")
guard bounds.count == 2, let min = Int(bounds[0]), let max = Int(bounds[1]) else {
return nil
}
self.min = min
self.max = max
}
}
/// A response handler that serves asset files.
struct FileRequestHandler: RequestHandlerFactory {
let rootURL: URL
let fileIO: NonBlockingFileIO
/// Metadata that pairs file paths with content mime types.
struct AssetFileMetadata {
let folderPath: String
let mimetype: (String) -> String
}
/// A list of predefined folder paths that are matched to expected content mime types.
///
/// All asset locations the preview server is supposed to serve, along with
/// a list of file and content types allowed in those locations.
static let assets: [AssetFileMetadata] = [
AssetFileMetadata(folderPath: "/data/", mimetype: { _ in "application/json" }),
AssetFileMetadata(folderPath: "/index/", mimetype: { _ in "application/json" }),
AssetFileMetadata(folderPath: "/css/", mimetype: { _ in "text/css" }),
AssetFileMetadata(folderPath: "/js/", mimetype: { _ in "text/javascript" }),
AssetFileMetadata(folderPath: "/fonts/", mimetype: { name in
switch name.fileExtension {
case "eot": return "application/vnd.ms-fontobject"
case "otf": return "font/otf"
case "woff": return "font/woff"
case "woff2": return "font/woff2"
default: return "application/octet-stream"
}
}),
AssetFileMetadata(folderPath: "/images/", mimetype: imageType),
AssetFileMetadata(folderPath: "/img/", mimetype: imageType),
AssetFileMetadata(folderPath: "/videos/", mimetype: { name in
switch name.fileExtension {
case "mpg": return "video/mpg"
case "m4", "mp4", "m4v": return "video/mp4"
case "mov": return "video/quicktime"
case "avi": return "video/x-msvideo"
default: return "application/octet-stream"
}
}),
AssetFileMetadata(folderPath: "/downloads/", mimetype: { name in
switch name.fileExtension {
case "zip": return "application/zip"
default: return "application/octet-stream"
}
})
]
struct TopLevelAssetFileMetadata {
let filePath: String
let mimetype: String
}
static let topLevelAssets = [
TopLevelAssetFileMetadata(filePath: "/apple-logo.svg", mimetype: "image/svg+xml"),
TopLevelAssetFileMetadata(filePath: "/favicon.ico", mimetype: "image/x-icon"),
TopLevelAssetFileMetadata(filePath: "/theme-settings.js", mimetype: "text/javascript"),
TopLevelAssetFileMetadata(filePath: "/theme-settings.json", mimetype: "application/json"),
]
/// Returns a Boolean value that indicates whether the given path is located inside an asset folder.
static func isAssetPath(_ path: String) -> Bool {
return matchingAssetMetadata(path) != nil
|| matchingTopLevelAssetMetadata(path) != nil
}
private static func matchingAssetMetadata(_ path: String) -> AssetFileMetadata? {
return assets.first(where: { metadata -> Bool in
return path.unicodeScalars.starts(with: metadata.folderPath.unicodeScalars)
})
}
private static func matchingTopLevelAssetMetadata(_ path: String) -> TopLevelAssetFileMetadata? {
return topLevelAssets.first(where: { metadata -> Bool in
return path == metadata.filePath
})
}
func create<ChannelHandler: ChannelInboundHandler>(channelHandler: ChannelHandler) -> RequestHandler
where ChannelHandler.OutboundOut == HTTPServerResponsePart {
return { ctx, head in
// Guards for a valid URL request
guard let components = URLComponents(string: head.uri) else { throw RequestError(status: .badRequest) }
// Guard that the path is authorized for serving assets
let mimetype: String
if let assetMetadata = FileRequestHandler.matchingAssetMetadata(components.path) {
mimetype = assetMetadata.mimetype(components.path)
} else if let topLevelAssetMetadata = FileRequestHandler.matchingTopLevelAssetMetadata(components.path) {
mimetype = topLevelAssetMetadata.mimetype
} else {
throw RequestError(status: .unauthorized)
}
let fileURL = self.rootURL.appendingPathComponent(components.path.removingLeadingSlash)
// Discard requests to components starting with a period or referring to the user directory
guard components.path.components(separatedBy: "/")
.allSatisfy({ !$0.hasPrefix(".") && $0 != "~" }) else { throw RequestError(status: .unauthorized) }
var data: Data
let totalLength: Int
// Read the file contents
do {
data = try Data(contentsOf: fileURL, options: .mappedIfSafe)
totalLength = data.count
} catch {
throw RequestError(status: .notFound)
}
// Add Range header if neccessary
var headers = HTTPHeaders()
let range = head.headers["Range"].first.flatMap(RangeHeader.init)
if let range {
data = data.subdata(in: Range<Data.Index>(uncheckedBounds: (lower: range.min, upper: range.max+1)))
headers.add(name: "Content-Range", value: "bytes \(range.min)-\(range.max)/\(totalLength)")
headers.add(name: "Accept-Ranges", value: "bytes")
}
// Write the response to the output channel
var content = ctx.channel.allocator.buffer(capacity: totalLength)
content.writeBytes(data)
headers.add(name: "Content-Length", value: "\(data.count)")
headers.add(name: "Content-Type", value: mimetype)
// No caching of live preview
headers.add(name: "Cache-Control", value: "no-store, no-cache, must-revalidate, post-check=0, pre-check=0")
headers.add(name: "Pragma", value: "no-cache")
let responseHead = HTTPResponseHead(matchingRequestHead: head, status: range != nil ? .partialContent : .ok, headers: headers)
ctx.write(channelHandler.wrapOutboundOut(.head(responseHead)), promise: nil)
ctx.write(channelHandler.wrapOutboundOut(.body(.byteBuffer(content))), promise: nil)
}
}
}
#endif
|
