Allow specifying a custom entrypoint & resources (#169)

Motivation
----------

This should allow users to add a debugserver and launch it.

Modifications
-------------

- Added a `--resources` flag that points to custom artifacts
- Added an option for a custom entrypoint

Result
------

You can add and run a debug server.

Test Plan
---------

Currently undergoing manual testing.

**Update:** Success

Author: Joannis

Plugins/ContainerImageBuilder/main.swift

@@ -48,6 +48,7 @@ extension PluginError: CustomStringConvertible {
 
                 OPTIONS
                   --product      Product to include in the image
+                  --resources    Directory of resources to include in the image
 
                 Other arguments are passed to the containertool helper.
                 """
@@ -89,16 +90,29 @@ extension PluginError: CustomStringConvertible {
 
         for built in builtExecutables { Diagnostics.remark("Built product: \(built.url.path)") }
 
-        let resources = builtExecutables[0].url
+        let resourcesBundle = builtExecutables[0].url
             .deletingLastPathComponent()
             .appendingPathComponent(
                 "\(context.package.displayName)_\(productName).resources"
             )
 
+        var resources: [String] = []
+        if FileManager.default.fileExists(atPath: resourcesBundle.path) {
+            resources.append(resourcesBundle.path)
+        }
+
+        for resource in extractor.extractOption(named: "resources") {
+            let paths = resource.split(separator: ":", maxSplits: 1)
+            if paths.count >= 1 && !FileManager.default.fileExists(atPath: String(paths[0])) {
+                throw PluginError.argumentError("Resource directory \(resource) does not exist")
+            }
+            resources.append(resource)
+        }
+
         // Run a command line helper to upload the image
         let helperURL = try context.tool(named: "containertool").url
         let helperArgs =
-            (FileManager.default.fileExists(atPath: resources.path) ? ["--resources", resources.path] : [])
+            resources.map { "--resources=\($0)" }
             + builtExecutables.map { $0.url.path }
             + extractor.remainingArguments
         let helperEnv = ProcessInfo.processInfo.environment.filter { $0.key.starts(with: "CONTAINERTOOL_") }

Sources/containertool/Extensions/Archive+appending.swift

@@ -47,11 +47,25 @@ extension Archive {
         try self.appendingFile(name: path.lastPathComponent, data: try [UInt8](Data(contentsOf: path)))
     }
 
+    func appendingFile(at path: URL, to destinationPath: URL) throws -> Self {
+        var ret = self
+        let data = try [UInt8](Data(contentsOf: path))
+        let components = destinationPath.pathComponents
+        precondition(!components.isEmpty, "Destination path is empty")
+        for i in 1..<components.count - 1 {
+            let directoryPath = components[..<i].joined(separator: "/")
+            try ret.appendDirectory(name: directoryPath)
+        }
+
+        try ret.appendFile(name: destinationPath.path(), data: data)
+        return ret
+    }
+
     /// Recursively append a single directory tree to the archive.
     /// Parameters:
     /// - root: The path to the directory to add.
     /// Returns:  A new archive made by appending `root` to the receiver.
-    func appendingDirectoryTree(at root: URL) throws -> Self {
+    func appendingDirectoryTree(at root: URL, to destinationPath: URL = URL(filePath: "/")) throws -> Self {
         var ret = self
 
         guard let enumerator = FileManager.default.enumerator(atPath: root.path) else {
@@ -66,6 +80,7 @@ extension Archive {
                 throw ("Unable to get file type for \(subpath)")
             }
 
+            let subpath = destinationPath.appending(path: subpath).path()
             switch filetype {
             case .typeRegular:
                 let resource = try [UInt8](Data(contentsOf: root.appending(path: subpath)))

Sources/containertool/Extensions/RegistryClient+publish.swift

@@ -12,6 +12,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+import class Foundation.FileManager
+import struct Foundation.ObjCBool
 import struct Foundation.Date
 import struct Foundation.URL
 
@@ -25,6 +27,7 @@ func publishContainerImage<Source: ImageSource, Destination: ImageDestination>(
     destination: Destination,
     architecture: String,
     os: String,
+    entrypoint: String?,
     cmd: [String],
     resources: [String],
     tag: String?,
@@ -50,17 +53,54 @@ func publishContainerImage<Source: ImageSource, Destination: ImageDestination>(
 
     var resourceLayers: [(descriptor: ContentDescriptor, diffID: ImageReference.Digest)] = []
     for resourceDir in resources {
-        let resourceTardiff = try Archive().appendingRecursively(atPath: resourceDir).bytes
-        let resourceLayer = try await destination.uploadLayer(
-            repository: destinationImage.repository,
-            contents: resourceTardiff
-        )
+        let paths = resourceDir.split(separator: ":", maxSplits: 1)
+        switch paths.count {
+        case 1:
+            let resourceTardiff = try Archive().appendingRecursively(atPath: resourceDir).bytes
+            let resourceLayer = try await destination.uploadLayer(
+                repository: destinationImage.repository,
+                contents: resourceTardiff
+            )
 
-        if verbose {
-            log("resource layer: \(resourceLayer.descriptor.digest) (\(resourceLayer.descriptor.size) bytes)")
-        }
+            if verbose {
+                log("resource layer: \(resourceLayer.descriptor.digest) (\(resourceLayer.descriptor.size) bytes)")
+            }
+
+            resourceLayers.append(resourceLayer)
+        case 2:
+            let sourcePath = paths[0]
+            let destinationPath = paths[1]
+
+            var isDirectory: ObjCBool = false
+            guard FileManager.default.fileExists(atPath: String(sourcePath), isDirectory: &isDirectory) else {
+                preconditionFailure("Source does not exist: \(source)")
+            }
+
+            let archive: Archive
+            if isDirectory.boolValue {
+                // archive = try Archive().appendingDirectoryTree(at: URL(fileURLWithPath: String(sourcePath)))
+                preconditionFailure("Directory trees are not supported yet")
+            } else {
+                archive = try Archive()
+                    .appendingFile(
+                        at: URL(fileURLWithPath: String(sourcePath)),
+                        to: URL(fileURLWithPath: String(destinationPath))
+                    )
+            }
+
+            let resourceLayer = try await destination.uploadLayer(
+                repository: destinationImage.repository,
+                contents: archive.bytes
+            )
 
-        resourceLayers.append(resourceLayer)
+            if verbose {
+                log("resource layer: \(resourceLayer.descriptor.digest) (\(resourceLayer.descriptor.size) bytes)")
+            }
+
+            resourceLayers.append(resourceLayer)
+        default:
+            preconditionFailure("Invalid resource directory: \(resourceDir)")
+        }
     }
 
     // MARK: Upload the application layer
@@ -80,7 +120,11 @@ func publishContainerImage<Source: ImageSource, Destination: ImageDestination>(
     // Inherit the configuration of the base image - UID, GID, environment etc -
     // and override the entrypoint.
     var inheritedConfiguration = baseImageConfiguration.config ?? .init()
-    inheritedConfiguration.Entrypoint = ["/\(executableURL.lastPathComponent)"]
+    if let entrypoint {
+        inheritedConfiguration.Entrypoint = [entrypoint]
+    } else {
+        inheritedConfiguration.Entrypoint = ["/\(executableURL.lastPathComponent)"]
+    }
     inheritedConfiguration.Cmd = cmd
     inheritedConfiguration.WorkingDir = "/"
 

Sources/containertool/containertool.swift

@@ -65,6 +65,9 @@ enum AllowHTTP: String, ExpressibleByArgument, CaseIterable { case source, desti
         @Option(help: "Operating system")
         var os: String?
 
+        @Option(help: "Entrypoint process")
+        var entrypoint: String?
+
         @Option(parsing: .remaining, help: "Default arguments to pass to the entrypoint process")
         var cmd: [String] = []
     }
@@ -225,6 +228,7 @@ enum AllowHTTP: String, ExpressibleByArgument, CaseIterable { case source, desti
             destination: destination,
             architecture: architecture,
             os: os,
+            entrypoint: imageConfigurationOptions.entrypoint,
             cmd: imageConfigurationOptions.cmd,
             resources: imageBuildOptions.resources,
             tag: repositoryOptions.tag,

Vendor/github.com/apple/swift-package-manager/Sources/Basics/AuthorizationProvider.swift

@@ -18,7 +18,7 @@ import struct Foundation.Data
 import struct Foundation.Date
 import struct Foundation.URL
 #if canImport(Security)
-    import Security
+import Security
 #endif
 
 public protocol AuthorizationProvider: Sendable {
@@ -56,14 +56,14 @@ public final class NetrcAuthorizationProvider: AuthorizationProvider {
     }
 
     public func authentication(for url: URL) -> (user: String, password: String)? {
-        return self.machine(for: url).map { (user: $0.login, password: $0.password) }
+        self.machine(for: url).map { (user: $0.login, password: $0.password) }
     }
 
     private func machine(for url: URL) -> Basics.Netrc.Machine? {
         // Since updates are appended to the end of the file, we
         // take the _last_ match to use the most recent entry.
         if let machine = NetrcAuthorizationProvider.machine(for: url),
-           let existing = self.netrc?.machines.last(where: { $0.name.lowercased() == machine })
+            let existing = self.netrc?.machines.last(where: { $0.name.lowercased() == machine })
         {
             return existing
         }

Vendor/github.com/apple/swift-package-manager/Sources/Basics/Netrc.swift

@@ -27,8 +27,10 @@ public struct Netrc: Sendable {
     /// - Parameters:
     ///   - url: The url to retrieve authorization information for.
     public func authorization(for url: URL) -> Authorization? {
-        guard let index = machines.firstIndex(where: { $0.name == url.host }) ?? machines
-            .firstIndex(where: { $0.isDefault })
+        guard
+            let index = machines.firstIndex(where: { $0.name == url.host })
+                ?? machines
+                .firstIndex(where: { $0.isDefault })
         else {
             return .none
         }
@@ -53,8 +55,10 @@ public struct Netrc: Sendable {
         }
 
         init?(for match: NSTextCheckingResult, string: String, variant: String = "") {
-            guard let name = RegexUtil.Token.machine.capture(in: match, string: string) ?? RegexUtil.Token.default
-                .capture(in: match, string: string),
+            guard
+                let name = RegexUtil.Token.machine.capture(in: match, string: string)
+                    ?? RegexUtil.Token.default
+                    .capture(in: match, string: string),
                 let login = RegexUtil.Token.login.capture(prefix: variant, in: match, string: string),
                 let password = RegexUtil.Token.password.capture(prefix: variant, in: match, string: string)
             else {
@@ -87,11 +91,12 @@ public struct NetrcParser {
         let matches = regex.matches(
             in: content,
             options: [],
-            range: NSRange(content.startIndex ..< content.endIndex, in: content)
+            range: NSRange(content.startIndex..<content.endIndex, in: content)
         )
 
         let machines: [Netrc.Machine] = matches.compactMap {
-            Netrc.Machine(for: $0, string: content, variant: "lp") ?? Netrc
+            Netrc.Machine(for: $0, string: content, variant: "lp")
+                ?? Netrc
                 .Machine(for: $0, string: content, variant: "pl")
         }
 
@@ -116,7 +121,8 @@ public struct NetrcParser {
         let matches = regex.matches(in: text, range: range)
         var trimmedCommentsText = text
         matches.forEach {
-            trimmedCommentsText = trimmedCommentsText
+            trimmedCommentsText =
+                trimmedCommentsText
                 .replacingOccurrences(of: nsString.substring(with: $0.range), with: "")
         }
         return trimmedCommentsText