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Page updated Jul 18, 2024

List file properties

You can list files without having to download all the files. You can do this by using the list API from the Amplify Library for Storage.

List Files

The following example lists all objects inside the public/photos/ path:

let listResult = try await Amplify.Storage.list(
path: .fromString("public/photos/")
)
listResult.items.forEach { item in
print("Path: \(item.path)")
}
let sink = Amplify.Publisher.create {
try await Amplify.Storage.list(
path: .fromString("public/photos/")
)
}.sink {
if case let .failure(error) = $0 {
print("Failed: \(error)")
}
}
receiveValue: { listResult in
listResult.items.forEach { item in
print("Path: \(item.path)")
}
}

Note the trailing slash / in the given path.

If you had used public/photos as path, it would also match against files like public/photos01.jpg.

Exclude results from nested subpaths

By default, the list API will return all objects contained within the given path, including objects inside nested subpaths.

For example, the previous public/photos/ path would include these objects:

Path: public/photos/photo1.jpg
Path: public/photos/vacation/photo1.jpg
Path: public/photos/thumbnails/photo1.jpg

In order to exclude objects within the vacation and thumbnails subpaths, you can set the subpathStrategy option to .exclude:

let listResult = try await Amplify.Storage.list(
path: .fromString("public/photos/"),
options: .init(
subpathStrategy: .exclude
)
)
listResult.items.forEach { item in
print("Path: \(item.path)")
}
listResult.excludedSubpaths.forEach { subpath in
print("Subpath: \(subpath)")
}
let sink = Amplify.Publisher.create {
try await Amplify.Storage.list(
path: .fromString("public/photos/"),
options: .init(
subpathStrategy: .exclude
)
)
}.sink {
if case let .failure(error) = $0 {
print("Failed: \(error)")
}
}
receiveValue: { listResult in
listResult.items.forEach { item in
print("Path: \(item.path)")
}
listResult.excludedSubpaths.forEach { subpath in
print("Subpath: \(subpath)")
}
}

The response will only include objects within the public/photos/ path and will also provide a list of the excluded subpaths:

Path: public/photos/photo01.jpg
Subpath: public/photos/vacation/
Subpath: public/photos/thumbnails/

The default delimiter character is "/", but this can be changed by supplying a custom delimiter:

let listResult = try await Amplify.Storage.list(
path: .fromString("public/photos-"),
options: .init(
subpathStrategy: .exclude(delimitedBy: "-")
)
)
let sink = Amplify.Publisher.create {
try await Amplify.Storage.list(
path: .fromString("public/photos-"),
options: .init(
subpathStrategy: .exclude(delimitedBy: "-")
)
)
}.sink {
if case let .failure(error) = $0 {
print("Failed: \(error)")
}
}
receiveValue: { listResult in
// ...
}

More list options

OptionTypeDescription
pageSizeUIntNumber between 1 and 1,000 that indicates the limit of how many entries to fetch when retrieving file lists from the server
nextTokenStringString indicating the page offset at which to resume a listing.

If the pageSize is set lower than the total file size available, a single list call only returns a subset of all the files. To list all the files with multiple calls, the user can use the nextToken value from the previous response.