Minify JS and CSS files

WebsiteGenerator/Extensions/URL+Extensions.swift

@@ -14,7 +14,17 @@ extension URL {
     }
 
     var isDirectory: Bool {
-        (try? resourceValues(forKeys: [.isDirectoryKey]))?.isDirectory == true
+        do {
+            let resources = try resourceValues(forKeys: [.isDirectoryKey])
+            guard let isDirectory = resources.isDirectory else {
+                print("No isDirectory info for \(path)")
+                return false
+            }
+            return isDirectory
+        } catch {
+            print("Failed to get directory information from \(path): \(error)")
+            return false
+        }
     }
 
     var exists: Bool {

WebsiteGenerator/Files/Configuration.swift

@@ -3,4 +3,6 @@ import Foundation
 struct Configuration {
 
     let pageImageWidth: Int
+
+    let minifyCSSandJS: Bool
 }

WebsiteGenerator/Files/FileSystem.swift

@@ -7,6 +7,8 @@ typealias SourceTextFile = (content: String, didChange: Bool)
 
 final class FileSystem {
 
+    private static let tempFileName = "temp.bin"
+
     private static let hashesFileName = "hashes.json"
 
     private let input: URL
@@ -19,6 +21,10 @@ final class FileSystem {
         input.appendingPathComponent(FileSystem.hashesFileName)
     }
 
+    private var tempFile: URL {
+        input.appendingPathComponent(FileSystem.tempFileName)
+    }
+
     /**
      The hashes of all accessed files from the previous run
 
@@ -357,7 +363,21 @@ final class FileSystem {
      Add a file as required, so that it will be copied to the output directory.
      */
     func require(file: String) {
+        let url = input.appendingPathComponent(file)
+        guard url.exists, url.isDirectory else {
             requiredFiles.insert(file)
+            return
+        }
+        do {
+            try FileManager.default
+                .contentsOfDirectory(atPath: url.path)
+                .forEach {
+                    // Recurse into subfolders
+                    require(file: file + "/" + $0)
+                }
+        } catch {
+            log.add(error: "Failed to read folder \(file): \(error)", source: source)
+        }
     }
 
     /**
@@ -391,17 +411,11 @@ final class FileSystem {
                 }
                 continue
             }
-            let data: Data
+            if copyFileIfChanged(from: sourceUrl, to: destinationUrl) {
-            do {
-                data = try Data(contentsOf: sourceUrl)
-            } catch {
-                log.add(error: "Failed to read data at \(sourceUrl.path)", source: source, error: error)
-                continue
-            }
-            if writeIfChanged(data, to: destinationUrl) {
                 copiedFiles.insert(file)
             }
         }
+        try? tempFile.delete()
         for (file, source) in expectedFiles {
             guard !isExternal(file: file) else {
                 continue
@@ -422,6 +436,52 @@ final class FileSystem {
         }
     }
 
+    private func copyFileIfChanged(from sourceUrl: URL, to destinationUrl: URL) -> Bool {
+        guard configuration.minifyCSSandJS else {
+            return copyBinaryFileIfChanged(from: sourceUrl, to: destinationUrl)
+        }
+        switch sourceUrl.pathExtension.lowercased() {
+        case "js":
+            return minifyJS(at: sourceUrl, andWriteTo: destinationUrl)
+        case "css":
+            return minifyCSS(at: sourceUrl, andWriteTo: destinationUrl)
+        default:
+            return copyBinaryFileIfChanged(from: sourceUrl, to: destinationUrl)
+        }
+    }
+
+    private func copyBinaryFileIfChanged(from sourceUrl: URL, to destinationUrl: URL) -> Bool {
+        do {
+            let data = try Data(contentsOf: sourceUrl)
+            return writeIfChanged(data, to: destinationUrl)
+        } catch {
+            log.add(error: "Failed to read data at \(sourceUrl.path)", source: source, error: error)
+            return false
+        }
+    }
+
+    private func minifyJS(at sourceUrl: URL, andWriteTo destinationUrl: URL) -> Bool {
+        let command = "uglifyjs \(sourceUrl.path) > \(tempFile.path)"
+        do {
+            _ = try safeShell(command)
+            return copyBinaryFileIfChanged(from: tempFile, to: destinationUrl)
+        } catch {
+            log.add(error: "Failed to minify \(sourceUrl.path): \(error)", source: source)
+            return false
+        }
+    }
+
+    private func minifyCSS(at sourceUrl: URL, andWriteTo destinationUrl: URL) -> Bool {
+        let command = "cleancss \(sourceUrl.path) -o \(tempFile.path)"
+        do {
+            _ = try safeShell(command)
+            return copyBinaryFileIfChanged(from: tempFile, to: destinationUrl)
+        } catch {
+            log.add(error: "Failed to minify \(sourceUrl.path): \(error)", source: source)
+            return false
+        }
+    }
+
     private func cleanRelativeURL(_ raw: String) -> String {
         let raw = raw.dropAfterLast("#") // Clean links to page content
         guard raw.contains("..") else {
@@ -468,7 +528,7 @@ final class FileSystem {
         guard !externalFiles.isEmpty else {
             return
         }
-        print("\(externalFiles.count) external files needed:")
+        print("\(externalFiles.count) external resources needed:")
         for file in externalFiles.sorted() {
             print("  " + file)
         }
@@ -553,6 +613,27 @@ final class FileSystem {
         let data = string.data(using: .utf8)!
         return writeIfChanged(data, to: url)
     }
+
+    // MARK: Running other tasks
+
+    @discardableResult
+    func safeShell(_ command: String) throws -> String {
+        let task = Process()
+        let pipe = Pipe()
+
+        task.standardOutput = pipe
+        task.standardError = pipe
+        task.arguments = ["-cl", command]
+        task.executableURL = URL(fileURLWithPath: "/bin/zsh")
+        task.standardInput = nil
+
+        try task.run()
+
+        let data = pipe.fileHandleForReading.readDataToEndOfFile()
+        let output = String(data: data, encoding: .utf8)!
+
+        return output
+    }
 }
 
 private extension Digest {

WebsiteGenerator/main.swift

@@ -3,7 +3,9 @@ import Foundation
 private let contentDirectory = URL(fileURLWithPath: "/Users/ch/Projects/MakerSpace")
 private let outputDirectory = URL(fileURLWithPath: "/Users/ch/Projects/MakerSpace/Site")
 
-let configuration = Configuration(pageImageWidth: 748)
+let configuration = Configuration(
+    pageImageWidth: 748,
+    minifyCSSandJS: true)
 
 let log = ValidationLog()
 let files = FileSystem(in: contentDirectory, to: outputDirectory)