43 lines
1.3 KiB
Swift
43 lines
1.3 KiB
Swift
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import Hummingbird
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import Infrastructure
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/// Keeps the site out of search engines: every response — pages, files, redirects, errors — is marked `X-Robots-Tag: noindex, nofollow`.
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///
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/// A header rather than `robots.txt`, which stays open on purpose: a crawler barred from a page never reads its `noindex`, and may still
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/// list the bare URL from links elsewhere. A header also covers what carries no markup, such as the photos sellers upload.
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public struct NoIndexMiddleware<Context: RequestContext>: RouterMiddleware {
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// MARK: Constants
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/// The directive stamped on every response.
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public static var directive: String { "noindex, nofollow" }
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// MARK: Initializers
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/// Creates the middleware.
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public init() {}
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// MARK: Methods
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public func handle(
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_ request: Request,
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context: Context,
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next: (Request, Context) async throws -> Response
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) async throws -> Response {
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do {
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var response = try await next(request, context)
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response.headers[.robotsTag] = Self.directive
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return response
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} catch let error as HTTPError {
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// An error thrown past this point becomes a response further out: the mark travels with it.
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var error = error
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error.headers[.robotsTag] = Self.directive
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throw error
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}
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}
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}
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