FlutterFlow and AWS S3 integration: Step-by-Step Guide 2024

      Before starting the integration process, ensure you have the following:

• A FlutterFlow project set up and running.
• An AWS account.
• AWS CLI installed on your machine (recommended but not mandatory).
• Basic familiarity with AWS S3 and FlutterFlow UI.

   

1. Go to the AWS Management Console.
2. Navigate to the S3 service.
3. Click on the Create bucket button.
   • Bucket Name: Choose a unique name.
   • Region: Select your preferred region.
4. Set the Bucket settings for Block Public Access as per your project requirement. (It's generally good to keep this enabled unless you specifically need public access.)
5. Click Create bucket to finalize.

   

1. Bucket Policy:
   • Go back to your bucket and navigate to the Permissions tab.
   • Under Bucket Policy, click Edit.
   • Add a policy similar to the following:

     ```
     {
         "Version": "2012-10-17",
         "Statement": [
             {
                 "Effect": "Allow",
                 "Principal": "*",
                 "Action": "s3:GetObject",
                 "Resource": "arn:aws:s3:::your-bucket-name/*"
             }
         ]
     }
     ```
     

2. CORS Configuration:
   • Still under the Permissions tab, scroll down to Cross-origin resource sharing (CORS) and click Edit.
   • Add a CORS rule similar to the following:

     ```
     [
         {
             "AllowedHeaders": ["*"],
             "AllowedMethods": ["GET", "PUT", "POST", "DELETE", "HEAD"],
             "AllowedOrigins": ["*"],
             "ExposeHeaders": ["ETag"],
             "MaxAgeSeconds": 3000
         }
     ]
     ```
     

   

1. Go to the IAM service in the AWS Management Console.
2. Navigate to Policies and click on Create policy.
3. Go to the JSON tab and add a policy like this, modifying `your-bucket-name`:

   ```
   {
       "Version": "2012-10-17",
       "Statement": [
           {
               "Effect": "Allow",
               "Action": [
                   "s3:ListBucket"
               ],
               "Resource": [
                   "arn:aws:s3:::your-bucket-name"
               ]
           },
           {
               "Effect": "Allow",
               "Action": [
                   "s3:GetObject",
                   "s3:PutObject",
                   "s3:DeleteObject"
               ],
               "Resource": [
                   "arn:aws:s3:::your-bucket-name/*"
               ]
           }
       ]
   }
   ```
   

4. Click Review policy, give it a name, and save it.
5. Go to Users and create or select a user.
   • Attach the policy you just created to this user.
6. Create or retrieve the Access Key ID and Secret Access Key for this user.

   

1. Open your FlutterFlow project.
2. Navigate to the Settings tab and select Environment Variables.
   • Add the following variables:
     • `AWS_ACCESS_KEY_ID`: Your AWS Access Key ID
     • `AWS_SECRET_ACCESS_KEY`: Your AWS Secret Access Key
     • `S3_BUCKET_NAME`: Your S3 bucket name
3. Open your Flutter project in an IDE (e.g., VS Code).

   

```
dependencies:
  flutter:
    sdk: flutter
  aws_s3_client: ^1.8.4
```

Run the `flutter pub get` command to install the dependencies.    

1. Create a new Dart file in your FlutterFlow project, e.g., `s3_service.dart`.
2. Add the following code to initialize and configure AWS S3:

   ```
   import 'package:aws_s3_client/aws\_s3.dart';
   import 'package:flutter_dotenv/flutter_dotenv.dart';
   
   class S3Service {
     final AwsS3 awsS3;
     
     S3Service()
       : awsS3 = AwsS3(
           region: 'YOUR_AWS_REGION',
           bucketId: dotenv.env['S3_BUCKET_NAME']!,
           accessKey: dotenv.env['AWS_ACCESS_KEY\_ID']!,
           secretKey: dotenv.env['AWS_SECRET_ACCESS\_KEY']!,
         );
   
     Future uploadFile(String filePath, String fileName) async {
       try {
         final result = await awsS3.uploadFile(
           filePath: filePath,
           fileKey: fileName,
           accessPolicy: S3AccessPolicy.public,
         );
         print('Upload successful: $result');
       } catch (e) {
         print('Upload failed: $e');
       }
     }
   
     Future downloadFile(String fileName, String downloadPath) async {
       try {
         final result = await awsS3.downloadFile(
           fileKey: fileName,
           downloadPath: downloadPath,
         );
         print('Download successful: $result');
       } catch (e) {
         print('Download failed: $e');
       }
     }
   }
   ```
   

3. Ensure you load environment variables in your main file:

   ```
   import 'package:flutter/material.dart';
   import 'package:flutter_dotenv/flutter_dotenv.dart';
   
   void main() async {
     await dotenv.load(fileName: ".env");
     runApp(MyApp());
   }
   ```
   

   

1. Create a new screen to serve as your file management interface.
2. Add buttons or other widgets for file upload and download.
3. Use the `S3Service` functions to handle the file upload/download logic. Here’s an example for file upload:

   ```
   import 'package:flutter/material.dart';
   import 'package:file_picker/file_picker.dart';
   import 's3\_service.dart';
   
   class FileUploadScreen extends StatelessWidget {
     final S3Service s3Service = S3Service();
   
     Future \_pickAndUploadFile() async {
       final result = await FilePicker.platform.pickFiles();
       if (result != null) {
         final file = result.files.first;
         await s3Service.uploadFile(file.path!, file.name);
       }
     }
   
     @override
     Widget build(BuildContext context) {
       return Scaffold(
         appBar: AppBar(title: Text('Upload File to S3')),
         body: Center(
           child: ElevatedButton(
             child: Text('Pick and Upload File'),
             onPressed: \_pickAndUploadFile,
           ),
         ),
       );
     }
   }
   ```
   

    You’ve now integrated AWS S3 with your FlutterFlow project. This guide has provided a comprehensive set of steps to create an S3 bucket, configure it, and use it within your FlutterFlow app. You can now extend these functionalities based on your project requirements.