The files are mostly png files, which don't have much metadata support natively, but even so, the metadata is not indexed by Finder/Spotlight so wouldn't work for me for this anyway.
Specifically, I am looking to add OCR text from my images into the comment field so that they are searchable. I have tried the methods in the links mentioned, and more.
I don't love the AppleScript method from xCode so am trying to do it "natively." I have gotten half way there with this:
func saveFinderComment(fileURL: URL, comment: String) -> Bool {
do {
let plistData = try PropertyListSerialization.data(fromPropertyList: comment, format: .binary, options: 0)
try fileURL.setExtendedAttribute(data: plistData, forName: "com.apple.metadata:kMDItemFinderComment")
} catch {
print("Error saving Finder comment: \(error)")
return false
}
return true
}
extension URL {
/// Get extended attribute.
func extendedAttribute(forName name: String) throws -> Data {
let data = try self.withUnsafeFileSystemRepresentation { fileSystemPath -> Data in
// Determine attribute size:
let length = getxattr(fileSystemPath, name, nil, 0, 0, 0)
guard length >= 0 else { throw URL.posixError(errno) }
// Create buffer with required size:
var data = Data(count: length)
// Retrieve attribute:
let result = data.withUnsafeMutableBytes { [count = data.count] in
getxattr(fileSystemPath, name, $0.baseAddress, count, 0, 0)
}
guard result >= 0 else { throw URL.posixError(errno) }
return data
}
return data
}
/// Set extended attribute.
func setExtendedAttribute(data: Data, forName name: String) throws {
try self.withUnsafeFileSystemRepresentation { fileSystemPath in
let result = data.withUnsafeBytes {
setxattr(fileSystemPath, name, $0.baseAddress, data.count, 0, 0)
}
guard result >= 0 else { throw URL.posixError(errno) }
}
}
/// Remove extended attribute.
func removeExtendedAttribute(forName name: String) throws {
try self.withUnsafeFileSystemRepresentation { fileSystemPath in
let result = removexattr(fileSystemPath, name, 0)
guard result >= 0 else { throw URL.posixError(errno) }
}
}
/// Get list of all extended attributes.
func listExtendedAttributes() throws -> [String] {
let list = try self.withUnsafeFileSystemRepresentation { fileSystemPath -> [String] in
let length = listxattr(fileSystemPath, nil, 0, 0)
guard length >= 0 else { throw URL.posixError(errno) }
// Create buffer with required size:
var namebuf = Array<CChar>(repeating: 0, count: length)
// Retrieve attribute list:
let result = listxattr(fileSystemPath, &namebuf, namebuf.count, 0)
guard result >= 0 else { throw URL.posixError(errno) }
// Extract attribute names:
let list = namebuf.split(separator: 0).compactMap {
$0.withUnsafeBufferPointer {
$0.withMemoryRebound(to: UInt8.self) {
String(bytes: $0, encoding: .utf8)
}
}
}
return list
}
return list
}
/// Helper function to create an NSError from a Unix errno.
private static func posixError(_ err: Int32) -> NSError {
return NSError(domain: NSPOSIXErrorDomain, code: Int(err),
userInfo: [NSLocalizedDescriptionKey: String(cString: strerror(err))])
}
}
It sets the extended attribute but not the .ds_store part. The data does become searchable, but I don't want to cut the corner - yet. Still working on it.
I am not the best developer, still learning.
Thank you MrHoffman, VikingOSX, and etresoft for your help - you have given me the hope to keep trying.
