Page updated Jan 16, 2024

List files

List keys under a specified path, as well as lastModified timestamp.

Public level list

Storage.list('photos/') // for listing ALL files without prefix, pass '' instead .then(({ results }) => console.log(results)) .catch((err) => console.log(err));
1Storage.list('photos/') // for listing ALL files without prefix, pass '' instead
2 .then(({ results }) => console.log(results))
3 .catch((err) => console.log(err));

Note the trailing slash / - if you had requested Storage.list('photos') it would also match against files like photos123.jpg alongside photos/123.jpg.

The format of the response will look similar to the below example

{ results: [ { eTag: ""30074401292215403a42b0739f3b5262"", key: "123.png", lastModified: "Thu Oct 08 2020 23:59:31 GMT+0800 (Singapore Standard Time)", size: 138256 }, // ... ], hasNextToken: false }
1{
2 results: [
3 {
4 eTag: ""30074401292215403a42b0739f3b5262"",
5 key: "123.png",
6 lastModified: "Thu Oct 08 2020 23:59:31 GMT+0800 (Singapore Standard Time)",
7 size: 138256
8 },
9 // ...
10 ],
11 hasNextToken: false
12}

Manually created folders will show up as files with a size of 0, but you can also match keys against a regex like file.key.match(/\.[0-9a-z]+$/i) to distinguish files vs folders. Since "folders" are a virtual concept in S3, any file may declare any depth of folder just by having a / in its name. If you need to list all the folders, you'll have to parse them accordingly to get an authoritative list of files and folders:

function processStorageList(response) { let files = []; let folders = new Set(); response.results.forEach((res) => { if (res.size) { files.push(res); // sometimes files declare a folder with a / within then let possibleFolder = res.key.split('/').slice(0, -1).join('/'); if (possibleFolder) folders.add(possibleFolder); } else { folders.add(res.key); } }); return { files, folders }; }
1function processStorageList(response) {
2 let files = [];
3 let folders = new Set();
4 response.results.forEach((res) => {
5 if (res.size) {
6 files.push(res);
7 // sometimes files declare a folder with a / within then
8 let possibleFolder = res.key.split('/').slice(0, -1).join('/');
9 if (possibleFolder) folders.add(possibleFolder);
10 } else {
11 folders.add(res.key);
12 }
13 });
14 return { files, folders };
15}

If you need the files and folders in terms of a nested object instead (for example, to build an explorer UI), you could parse it recursively:

function processStorageList(response) { const filesystem = {}; // https://stackoverflow.com/questions/44759750/how-can-i-create-a-nested-object-representation-of-a-folder-structure const add = (source, target, item) => { const elements = source.split('/'); const element = elements.shift(); if (!element) return; // blank target[element] = target[element] || { __data: item }; // element; if (elements.length) { target[element] = typeof target[element] === 'object' ? target[element] : {}; add(elements.join('/'), target[element], item); } }; response.results.forEach((item) => add(item.key, filesystem, item)); return filesystem; }
1function processStorageList(response) {
2 const filesystem = {};
3 // https://stackoverflow.com/questions/44759750/how-can-i-create-a-nested-object-representation-of-a-folder-structure
4 const add = (source, target, item) => {
5 const elements = source.split('/');
6 const element = elements.shift();
7 if (!element) return; // blank
8 target[element] = target[element] || { __data: item }; // element;
9 if (elements.length) {
10 target[element] =
11 typeof target[element] === 'object' ? target[element] : {};
12 add(elements.join('/'), target[element], item);
13 }
14 };
15 response.results.forEach((item) => add(item.key, filesystem, item));
16 return filesystem;
17}

This places each item's data inside a special __data key.

Protected level list

To list current user's objects:

Storage.list('photos/', { level: 'protected' }) .then(({ results }) => console.log(results)) .catch((err) => console.log(err));
1Storage.list('photos/', { level: 'protected' })
2 .then(({ results }) => console.log(results))
3 .catch((err) => console.log(err));

To get other users' objects:

Storage.list('photos/', { level: 'protected', identityId: 'xxxxxxx' // the identityId of that user }) .then(({ results }) => console.log(results)) .catch((err) => console.log(err));
1Storage.list('photos/', {
2 level: 'protected',
3 identityId: 'xxxxxxx' // the identityId of that user
4})
5 .then(({ results }) => console.log(results))
6 .catch((err) => console.log(err));

Private level list

Storage.list('photos/', { level: 'private' }) .then(({ results }) => console.log(results)) .catch((err) => console.log(err));
1Storage.list('photos/', { level: 'private' })
2 .then(({ results }) => console.log(results))
3 .catch((err) => console.log(err));

Access all files

To get a list of all files in your S3 bucket under a specific prefix, you can set pageSize to ALL. The default value of pageSize is 1000.

Storage.list('photos/', { pageSize: 'ALL' }) .then(({ results }) => console.log(result)) .catch((err) => console.log(err));
1Storage.list('photos/', { pageSize: 'ALL' })
2 .then(({ results }) => console.log(result))
3 .catch((err) => console.log(err));

Paginated file access

If the pageSize is set lower than the total file size, a single Storage.list call only returns a subset of all the files. To list all the files with multiple calls, users can use the hasNextToken and nextToken keys:

const PAGE_SIZE = 20; let nextToken = undefined; let hasNextPage = true; //... const loadNextPage = async () => { if (hasNextPage) { let response = await Storage.list('', { pageSize: PAGE_SIZE, nextToken: nextToken }); if (response.hasNextToken) { nextToken = response.nextToken; } else { nextToken = undefined; hasNextPage = false; } // render list items from response.results } };
1const PAGE_SIZE = 20;
2let nextToken = undefined;
3let hasNextPage = true;
4//...
5const loadNextPage = async () => {
6 if (hasNextPage) {
7 let response = await Storage.list('', {
8 pageSize: PAGE_SIZE,
9 nextToken: nextToken
10 });
11 if (response.hasNextToken) {
12 nextToken = response.nextToken;
13 } else {
14 nextToken = undefined;
15 hasNextPage = false;
16 }
17 // render list items from response.results
18 }
19};
Note: The range of pageSize can be from 0 - 1000 or 'ALL'.