diff --git a/CHANGELOG.md b/CHANGELOG.md
index 33a6206..5e25022 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.12.13
+- Upgrade packages
+- Correct deprecated methods
+
 ## 0.12.11
 
 - Switch from `http_client` package to `http` package
diff --git a/analysis_options.yaml b/analysis_options.yaml
index 97f0908..86f043d 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -1,15 +1,13 @@
-analyzer:
-  strong-mode: true
 #   exclude:
 #     - path/to/excluded/files/**
 
 # Lint rules and documentation, see http://dart-lang.github.io/linter/lints
 linter:
   rules:
-    - cancel_subscriptions
-    - hash_and_equals
-    - iterable_contains_unrelated_type
-    - list_remove_unrelated_type
-    - test_types_in_equals
-    - unrelated_type_equality_checks
-    - valid_regexps
+    cancel_subscriptions: true
+    hash_and_equals: true
+    iterable_contains_unrelated_type: true
+    list_remove_unrelated_type: true
+    test_types_in_equals: true
+    unrelated_type_equality_checks: true
+    valid_regexps: true
diff --git a/example/dospace_example.dart b/example/dospace_example.dart
index e3bb1d5..c9955ca 100644
--- a/example/dospace_example.dart
+++ b/example/dospace_example.dart
@@ -25,7 +25,7 @@ main() async {
     }
   }
   dospace.Bucket bucket = spaces.bucket(bucketName);
-  String etag = await bucket.uploadFile(
+  String? etag = await bucket.uploadFile(
       'README.md', 'README.md', 'text/plain', dospace.Permissions.public);
   print('upload: $etag');
 
@@ -34,7 +34,7 @@ main() async {
 
   // Basic pre-signed upload
   {
-    String preSignUrl = bucket.preSignUpload('README.md');
+    String preSignUrl = bucket.preSignUpload('README.md')!;
     print('upload url: ${preSignUrl}');
     var httpClient = new http.Client();
     var httpRequest = new http.Request('PUT', Uri.parse(preSignUrl));
@@ -42,7 +42,7 @@ main() async {
     String body = await utf8.decodeStream(httpResponse.stream);
     print('${httpResponse.statusCode} ${httpResponse.reasonPhrase}');
     print(body);
-    await httpClient.close();
+    httpClient.close();
   }
 
   // Pre-signed upload with specific payload
@@ -51,7 +51,7 @@ main() async {
     int contentLength = await input.length();
     Digest contentSha256 = await sha256.bind(input.openRead()).first;
     String preSignUrl = bucket.preSignUpload('README.md',
-        contentLength: contentLength, contentSha256: contentSha256);
+        contentLength: contentLength, contentSha256: contentSha256)!;
     print('strict upload url: ${preSignUrl}');
     var httpClient = new http.Client();
     var httpRequest = new http.Request('PUT', Uri.parse(preSignUrl));
@@ -59,7 +59,7 @@ main() async {
     String body = await utf8.decodeStream(httpResponse.stream);
     print('${httpResponse.statusCode} ${httpResponse.reasonPhrase}');
     print(body);
-    await httpClient.close();
+    httpClient.close();
   }
 
   print('done');
diff --git a/lib/src/dospace_bucket.dart b/lib/src/dospace_bucket.dart
index 16869f3..22f80e6 100644
--- a/lib/src/dospace_bucket.dart
+++ b/lib/src/dospace_bucket.dart
@@ -16,11 +16,11 @@ enum Permissions {
 
 class Bucket extends Client {
   Bucket(
-      {@required String region,
-      @required String accessKey,
-      @required String secretKey,
-      String endpointUrl,
-      http.Client httpClient})
+      {required String? region,
+      required String? accessKey,
+      required String? secretKey,
+      String? endpointUrl,
+      http.Client? httpClient})
       : super(
             region: region,
             accessKey: accessKey,
@@ -39,12 +39,32 @@ class Bucket extends Client {
     }
   }
 
+  /// Delete an object
+  /// https://developers.digitalocean.com/documentation/spaces/#delete-object
+  Future<bool> deleteFile(String path) async {
+    String uriStr = endpointUrl + '/' + path;
+    http.Request request = new http.Request('DELETE', Uri.parse(uriStr));
+    request.headers['Content-Type'] = "application/json";
+    signRequest(request);
+
+    http.StreamedResponse response = await httpClient.send(request);
+    String body = await utf8.decodeStream(response.stream);
+
+    // "204 No Content" means the object was deleted (success)
+    if (response.statusCode != 204) {
+      throw new ClientException(
+          response.statusCode, response.reasonPhrase, response.headers, body);
+    }
+
+    return Future<bool>.value(true);
+  }
+
   /// List the Bucket's Contents.
   /// https://developers.digitalocean.com/documentation/spaces/#list-bucket-contents
   Stream<BucketContent> listContents(
-      {String delimiter, String prefix, int maxKeys}) async* {
-    bool isTruncated;
-    String marker;
+      {String? delimiter, String? prefix, int? maxKeys}) async* {
+    late bool isTruncated;
+    String? marker;
     do {
       Uri uri = Uri.parse(endpointUrl + '/');
       Map<String, dynamic> params = new Map<String, dynamic>();
@@ -70,10 +90,10 @@ class Bucket extends Client {
                     ele.text.toLowerCase() != "false" && ele.text != "0";
                 break;
               case "Contents":
-                String key;
-                DateTime lastModifiedUtc;
-                String eTag;
-                int size;
+                String? key;
+                DateTime? lastModifiedUtc;
+                String? eTag;
+                int? size;
                 for (xml.XmlNode node in ele.children) {
                   if (node is xml.XmlElement) {
                     xml.XmlElement ele = node;
@@ -108,10 +128,10 @@ class Bucket extends Client {
   }
 
   /// Uploads file. Returns Etag.
-  Future<String> uploadFile(
+  Future<String?> uploadFile(
       String key, dynamic file, String contentType, Permissions permissions,
-      {Map<String, String> meta}) async {
-    int contentLength = await file.length();
+      {Map<String, String>? meta}) async {
+    int? contentLength = await file.length();
     Digest contentSha256 = await sha256.bind(file.openRead()).first;
     String uriStr = endpointUrl + '/' + key;
     http.StreamedRequest request =
@@ -136,14 +156,14 @@ class Bucket extends Client {
       throw new ClientException(
           response.statusCode, response.reasonPhrase, response.headers, body);
     }
-    String etag = response.headers['etag'];
+    String? etag = response.headers['etag'];
     return etag;
   }
 
   /// Uploads data from memory. Returns Etag.
-  Future<String> uploadData(
+  Future<String?> uploadData(
       String key, Uint8List data, String contentType, Permissions permissions,
-      {Map<String, String> meta, Digest contentSha256}) async {
+      {Map<String, String>? meta, Digest? contentSha256}) async {
     int contentLength = await data.length;
     Digest contentSha256_ =
         contentSha256 != null ? contentSha256 : await sha256.convert(data);
@@ -168,17 +188,17 @@ class Bucket extends Client {
       throw new ClientException(
           response.statusCode, response.reasonPhrase, response.headers, body);
     }
-    String etag = response.headers['etag'];
+    String? etag = response.headers['etag'];
     return etag;
   }
 
-  String preSignUpload(String key,
-      {int contentLength,
-      String contentType,
-      Digest contentSha256,
+  String? preSignUpload(String key,
+      {int? contentLength,
+      String? contentType,
+      Digest? contentSha256,
       Permissions permissions = Permissions.private,
       int expires = 900,
-      Map<String, String> meta}) {
+      Map<String, String>? meta}) {
     String uriStr = endpointUrl + '/' + key;
     Uri uriBase = Uri.parse(uriStr);
     Map<String, String> queryParameters = new Map<String, String>();
diff --git a/lib/src/dospace_client.dart b/lib/src/dospace_client.dart
index 9584903..ec7c80d 100644
--- a/lib/src/dospace_client.dart
+++ b/lib/src/dospace_client.dart
@@ -7,7 +7,7 @@ import 'package:xml/xml.dart' as xml;
 
 class ClientException implements Exception {
   final int statusCode;
-  final String reasonPhrase;
+  final String? reasonPhrase;
   final Map<String, String> responseHeaders;
   final String responseBody;
   const ClientException(this.statusCode, this.reasonPhrase,
@@ -18,9 +18,9 @@ class ClientException implements Exception {
 }
 
 class Client {
-  final String region;
-  final String accessKey;
-  final String secretKey;
+  final String? region;
+  final String? accessKey;
+  final String? secretKey;
   final String service;
   final String endpointUrl;
 
@@ -28,12 +28,12 @@ class Client {
   final http.Client httpClient;
 
   Client(
-      {@required this.region,
-      @required this.accessKey,
-      @required this.secretKey,
-      @required this.service,
-      String endpointUrl,
-      http.Client httpClient})
+      {required this.region,
+      required this.accessKey,
+      required this.secretKey,
+      required this.service,
+      String? endpointUrl,
+      http.Client? httpClient})
       : this.endpointUrl =
             endpointUrl ?? "https://${region}.digitaloceanspaces.com",
         this.httpClient = httpClient ?? new http.Client() {
@@ -43,7 +43,7 @@ class Client {
   }
 
   Future<void> close() async {
-    await httpClient.close();
+    httpClient.close();
   }
 
   @protected
@@ -56,7 +56,7 @@ class Client {
       throw new ClientException(
           response.statusCode, response.reasonPhrase, response.headers, body);
     }
-    xml.XmlDocument doc = xml.parse(body);
+    xml.XmlDocument doc = xml.XmlDocument.parse(body);
     return doc;
   }
 
@@ -75,8 +75,8 @@ class Client {
   }
 
   @protected
-  String signRequest(http.BaseRequest request,
-      {Digest contentSha256, bool preSignedUrl = false, int expires = 86400}) {
+  String? signRequest(http.BaseRequest request,
+      {Digest? contentSha256, bool preSignedUrl = false, int expires = 86400}) {
     // Build canonical request
     String httpMethod = request.method;
     String canonicalURI = request.url.path;
@@ -104,7 +104,7 @@ class Client {
         '${accessKey}/${dateYYYYMMDD}/${region}/${service}/aws4_request';
 
     // Build canonical headers string
-    Map<String, String> headers = new Map<String, String>();
+    Map<String, String?> headers = new Map<String, String?>();
     if (!preSignedUrl) {
       request.headers['x-amz-date'] = dateIso8601; // Set date in header
       if (contentSha256 != null) {
@@ -117,7 +117,7 @@ class Client {
     headers['host'] = host; // Host is a builtin header
     List<String> headerNames = headers.keys.toList()..sort();
     String canonicalHeaders =
-        headerNames.map((s) => '${s}:${_trimAll(headers[s])}' + '\n').join();
+        headerNames.map((s) => '${s}:${_trimAll(headers[s]!)}' + '\n').join();
 
     String signedHeaders = headerNames.join(';');
 
@@ -137,7 +137,7 @@ class Client {
     }
     List<String> queryKeys = queryParameters.keys.toList()..sort();
     String canonicalQueryString = queryKeys
-        .map((s) => '${_uriEncode(s)}=${_uriEncode(queryParameters[s])}')
+        .map((s) => '${_uriEncode(s)}=${_uriEncode(queryParameters[s]!)}')
         .join('&');
 
     if (preSignedUrl) {
@@ -160,7 +160,7 @@ class Client {
     Digest dateKey = new Hmac(sha256, utf8.encode("AWS4${secretKey}"))
         .convert(utf8.encode(dateYYYYMMDD));
     Digest dateRegionKey =
-        new Hmac(sha256, dateKey.bytes).convert(utf8.encode(region));
+        new Hmac(sha256, dateKey.bytes).convert(utf8.encode(region!));
     Digest dateRegionServiceKey =
         new Hmac(sha256, dateRegionKey.bytes).convert(utf8.encode(service));
     Digest signingKey = new Hmac(sha256, dateRegionServiceKey.bytes)
diff --git a/lib/src/dospace_results.dart b/lib/src/dospace_results.dart
index da7ccec..a66245a 100644
--- a/lib/src/dospace_results.dart
+++ b/lib/src/dospace_results.dart
@@ -2,21 +2,21 @@ import 'package:meta/meta.dart';
 
 class BucketContent {
   /// The object's key.
-  final String key;
+  final String? key;
 
   /// The date and time that the object was last modified in the format: %Y-%m-%dT%H:%M:%S.%3NZ (e.g. 2017-06-23T18:37:48.157Z)
-  final DateTime lastModifiedUtc;
+  final DateTime? lastModifiedUtc;
 
   /// The entity tag containing an MD5 hash of the object.
-  final String eTag;
+  final String? eTag;
 
   /// The size of the object in bytes.
-  final int size;
+  final int? size;
 
   BucketContent({
-    @required this.key,
-    @required this.lastModifiedUtc,
-    @required this.eTag,
-    @required this.size,
+    required this.key,
+    required this.lastModifiedUtc,
+    required this.eTag,
+    required this.size,
   });
 }
diff --git a/lib/src/dospace_spaces.dart b/lib/src/dospace_spaces.dart
index daa57dc..0f8e72e 100644
--- a/lib/src/dospace_spaces.dart
+++ b/lib/src/dospace_spaces.dart
@@ -8,11 +8,11 @@ import 'dospace_bucket.dart';
 
 class Spaces extends Client {
   Spaces(
-      {@required String region,
-      @required String accessKey,
-      @required String secretKey,
-      String endpointUrl,
-      http.Client httpClient})
+      {required String? region,
+      required String? accessKey,
+      required String? secretKey,
+      String? endpointUrl,
+      http.Client? httpClient})
       : super(
             region: region,
             accessKey: accessKey,
@@ -23,7 +23,7 @@ class Spaces extends Client {
     // ...
   }
 
-  Bucket bucket(String bucket) {
+  Bucket bucket(String? bucket) {
     if (endpointUrl == "https://${region}.digitaloceanspaces.com") {
       return new Bucket(
           region: region,
@@ -39,7 +39,7 @@ class Spaces extends Client {
 
   Future<List<String>> listAllBuckets() async {
     xml.XmlDocument doc = await getUri(Uri.parse(endpointUrl + '/'));
-    List<String> res = new List<String>();
+    List<String> res = new List<String>.empty(growable: true);
     for (xml.XmlElement root in doc.findElements('ListAllMyBucketsResult')) {
       for (xml.XmlElement buckets in root.findElements('Buckets')) {
         for (xml.XmlElement bucket in buckets.findElements('Bucket')) {
@@ -52,7 +52,7 @@ class Spaces extends Client {
     return res;
   }
 
-  String preSignListAllBuckets() {
+  String? preSignListAllBuckets() {
     http.Request request =
         new http.Request('GET', Uri.parse(endpointUrl + '/'));
     return signRequest(request, preSignedUrl: true);
diff --git a/pubspec.yaml b/pubspec.yaml
index ef30576..fc8b055 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,18 +1,20 @@
 name: dospace
-description: Client library to interact with the DigitalOcean Spaces API. Same API as Amazon AWS S3.
-version: 0.12.12
+description: Client library to interact with the DigitalOcean Spaces API. Same
+  API as Amazon AWS S3.
+version: 0.12.13
 homepage: https://github.com/nbspou/dospace
 author: NO-BREAK SPACE OÜ <support@no-break.space>
 
 environment:
-  sdk: '>=2.0.0-dev.58.0 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
-  meta: ^1.1.5
-  crypto: ^2.0.6
-  http: ^0.12.0
-  xml: ^3.0.1
+  crypto: ^3.0.1
+  http: ^0.13.1
+  meta: ^1.3.0
+  mime: ^1.0.0
+  xml: ^6.1.0
 
 dev_dependencies:
-  test: ^1.0.0
-  ini: ^2.0.1
+  ini: ^2.1.0
+  test: ^1.16.8
diff --git a/test/dospace_test.dart b/test/dospace_test.dart
index 76bf687..ac66de2 100644
--- a/test/dospace_test.dart
+++ b/test/dospace_test.dart
@@ -4,10 +4,11 @@ import 'dart:typed_data';
 import 'package:crypto/crypto.dart';
 import 'package:dospace/dospace.dart' as dospace;
 import 'package:ini/ini.dart' as ini;
+import 'package:mime/mime.dart';
 import 'package:test/test.dart';
 
-dospace.Spaces spaces;
-dospace.Bucket bucket;
+dospace.Spaces? spaces;
+dospace.Bucket? bucket;
 
 Future<void> main() async {
   List<String> lines = await new File("test/test.ini").readAsLines();
@@ -15,31 +16,36 @@ Future<void> main() async {
 
   setUp(() async {
     spaces = new dospace.Spaces(
-      region: cfg.get("Spaces", "region"),
-      accessKey: cfg.get("Spaces", "key"),
-      secretKey: cfg.get("Spaces", "secret"),
+      region: cfg.get("section", "region"),
+      accessKey: cfg.get("section", "accessKey"),
+      secretKey: cfg.get("section", "secretKey"),
     );
-    bucket = spaces.bucket(cfg.get("Bucket", "bucket"));
+    bucket = spaces!.bucket(cfg.get("section", "bucketName"));
   });
 
   tearDown(() async {
-    await spaces.close();
+    await spaces!.close();
     bucket = null;
     spaces = null;
   });
 
   test("Bucket is in Spaces", () async {
-    List<String> buckets = await spaces.listAllBuckets();
-    expect(buckets, contains(cfg.get("Bucket", "bucket")));
+    List<String> buckets = await spaces!.listAllBuckets();
+    expect(buckets, contains(cfg.get("section", "bucketName")));
   });
 
   test("Upload file", () async {
-    String etag = await bucket.uploadFile(
+    String? etag = await bucket!.uploadFile(
         "dospace_test.dart",
-        new File("test/dospace_test.dart"),
-        "text/plain",
+        File("test/dospace_test.dart"),
+        lookupMimeType(File("test/dospace_test.dart").path)!,
         dospace.Permissions.public);
     expect(etag, isNotEmpty);
+  }, timeout: Timeout(Duration(seconds: 20)));
+
+  test("Delete file", () async {
+    bool etag = await bucket!.deleteFile('dospace_test.dart');
+    expect(etag, isTrue);
   });
 
   test("Upload binary data", () async {
@@ -47,7 +53,7 @@ Future<void> main() async {
         await new File("test/dospace_test.dart").readAsBytes());
     Digest contentSha256 = sha256.convert(data);
     String key = "test/user/1/$contentSha256.dart";
-    bucket.uploadData(key, data, "text/plain", dospace.Permissions.public,
+    bucket!.uploadData(key, data, "text/plain", dospace.Permissions.public,
         contentSha256: contentSha256);
   });
 }
diff --git a/test/flutter_outline.mp4 b/test/flutter_outline.mp4
new file mode 100644
index 0000000..7bc937f
Binary files /dev/null and b/test/flutter_outline.mp4 differ