WIP - Replaced get_it + injectable with Provider

packages/paperless_api/lib/src/request_utils.dart

@@ -0,0 +1,75 @@
+import 'dart:io';
+
+import 'package:dio/dio.dart';
+import 'package:flutter/foundation.dart';
+import 'package:paperless_api/src/models/paperless_server_exception.dart';
+
+Future<T> getSingleResult<T>(
+  String url,
+  T Function(Map<String, dynamic>) fromJson,
+  ErrorCode errorCode, {
+  required Dio client,
+  int minRequiredApiVersion = 1,
+}) async {
+  final response = await client.get(
+    url,
+    options: Options(
+      headers: {'accept': 'application/json; version=$minRequiredApiVersion'},
+    ),
+  );
+  if (response.statusCode == HttpStatus.ok) {
+    return compute(
+      fromJson,
+      response.data as Map<String, dynamic>,
+    );
+  }
+  throw PaperlessServerException(
+    errorCode,
+    httpStatusCode: response.statusCode,
+  );
+}
+
+Future<List<T>> getCollection<T>(
+  String url,
+  T Function(Map<String, dynamic>) fromJson,
+  ErrorCode errorCode, {
+  required Dio client,
+  int minRequiredApiVersion = 1,
+}) async {
+  final response = await client.get(
+    url,
+    options: Options(headers: {
+      'accept': 'application/json; version=$minRequiredApiVersion'
+    }),
+  );
+  if (response.statusCode == HttpStatus.ok) {
+    final Map<String, dynamic> body = response.data;
+    if (body.containsKey('count')) {
+      if (body['count'] == 0) {
+        return <T>[];
+      } else {
+        return compute(
+          _collectionFromJson,
+          _CollectionFromJsonSerializationParams(
+              fromJson, (body['results'] as List).cast<Map<String, dynamic>>()),
+        );
+      }
+    }
+  }
+  throw PaperlessServerException(
+    errorCode,
+    httpStatusCode: response.statusCode,
+  );
+}
+
+List<T> _collectionFromJson<T>(
+    _CollectionFromJsonSerializationParams<T> params) {
+  return params.list.map<T>((result) => params.fromJson(result)).toList();
+}
+
+class _CollectionFromJsonSerializationParams<T> {
+  final T Function(Map<String, dynamic>) fromJson;
+  final List<Map<String, dynamic>> list;
+
+  _CollectionFromJsonSerializationParams(this.fromJson, this.list);
+}