Solving the Mysterious Case of Missing Stack Traces and Source Maps in Sentry with Flutter

Are you tired of getting frustrated with the infamous “missing stack traces” and “missing_source_content” error in Sentry when using Flutter? You’re not alone!
In this article, we’ll embark on a mission to demystify the culprit behind this issue and provide you with clear, step-by-step instructions to get your Sentry setup up and running smoothly.

Understanding the Problem: What are Source Maps and Stack Traces?

Before we dive into the solution, let’s quickly understand what source maps and stack traces are, and why they’re essential for error tracking in Sentry.

What are Source Maps?

Source maps are files that map minified or compiled code to its original source code. In the context of Flutter, source maps are generated when you compile your Dart code to JavaScript. These maps allow Sentry to reconstruct the original code, making it possible to display meaningful stack traces.

What are Stack Traces?

A stack trace is a detailed report of the sequence of method calls that led to an error or exception. It’s like a breadcrumb trail that helps you identify the exact location and cause of the error. In Sentry, stack traces are crucial for debugging and identifying the root cause of issues.

The Error: Missing Stack Traces and Missing Source Maps

Now that we’ve covered the basics, let’s discuss the error that’s been plaguing us: missing stack traces and source maps in Sentry. When you encounter this issue, you’ll typically see an error message like this:

Error: missing stack trace
Error: missing_source_content

This error occurs when Sentry can’t find the source maps or can’t reconstruct the stack trace. This can happen due to various reasons, including:

• Incorrect or missing source map files
• Inconsistent or outdated versions of Flutter, Sentry, or other dependencies
• Improper configuration of Sentry or Flutter

The Solution: Step-by-Step Guide to Resolving Missing Stack Traces and Source Maps

Now, let’s get to the good stuff! Here’s a comprehensive, step-by-step guide to resolving the missing stack traces and source maps issue in Sentry with Flutter:

Step 1: Verify Your Sentry Configuration

First, ensure that you’ve correctly configured Sentry in your Flutter project. Here’s a sample configuration to get you started:

import 'package:sentry_flutter/sentry_flutter.dart';

Future main() async {
  await SentryFlutter.init(
    (options) {
      options.dsn = 'YOUR_DSN_HERE';
      options.tracesSampleRate = 1.0;
    },
    appRunner: () => runApp(MyApp()),
  );
}

Make sure to replace `YOUR_DSN_HERE` with your actual Sentry DSN.

Step 2: Generate Source Maps

Next, you need to generate source maps for your Flutter project. You can do this using the `flutter build` command:

flutter build web --source-maps

This command will generate a `dart_js.dart.js` file in your project’s `build` directory, along with a corresponding source map file.

Step 3: Upload Source Maps to Sentry

Now, you need to upload the generated source maps to Sentry. You can do this using the Sentry CLI or the Sentry Web API.

Using the Sentry CLI:

sentry-cli uploads create --type sourcemap --sdk-version 1.0.0 \
  --url https://[email protected]/api/0/projects/PROJECT_ID/upload/sourcemaps \
  build/dart_js.dart.js.map

Replace `YOUR_DSN_HERE` with your actual Sentry DSN and `PROJECT_ID` with your project ID.

Using the Sentry Web API:

curl -X POST \
  https://api.sentry.io/api/0/projects/PROJECT_ID/upload/sourcemaps \
  -H 'Authorization: Bearer YOUR_DSN_HERE' \
  -H 'Content-Type: application/octet-stream' \
  -T build/dart_js.dart.js.map

Again, replace `YOUR_DSN_HERE` with your actual Sentry DSN and `PROJECT_ID` with your project ID.

Step 4: Verify Source Maps Upload

After uploading the source maps, verify that they’re correctly uploaded to Sentry. You can do this by checking the Sentry dashboard or using the Sentry CLI:

sentry-cli uploads list --type sourcemap

This command will list all uploaded source maps for your project.

Step 5: Configure Flutter to Send Source Maps to Sentry

Finally, you need to configure Flutter to send the source maps to Sentry when an error occurs. You can do this by adding the following code to your `SentryFlutter` configuration:

import 'package:sentry_flutter/sentry_flutter.dart';

Future main() async {
  await SentryFlutter.init(
    (options) {
      options.dsn = 'YOUR_DSN_HERE';
      options.tracesSampleRate = 1.0;
      options.beforeSend: (event, hint) {
        final mapper = SentryFlutterMapper();
        return mapper.mapEvent(event, hint);
      },
    },
    appRunner: () => runApp(MyApp()),
  );
}

This code sets up the `beforeSend` callback to use the `SentryFlutterMapper` to send the correct source maps to Sentry.

Step	Description
1	Verify Sentry configuration
2	Generate source maps using flutter build
3	Upload source maps to Sentry using CLI or Web API
4	Verify source maps upload
5	Configure Flutter to send source maps to Sentry

Conclusion: Basking in the Glory of Correctly Configured Sentry

With these steps, you should now have a correctly configured Sentry setup with Flutter, complete with source maps and stack traces. Remember to be patient and methodical when troubleshooting, as the solution might require a combination of these steps.

By following this guide, you’ll be able to:

• Generate and upload source maps to Sentry
• Configure Flutter to send source maps to Sentry
• Resolve the missing stack traces and source maps issue

Now, go forth and conquer the world of error tracking with Sentry and Flutter!

Here are 5 questions and answers about “Sentry flutter source maps missing stack traces and missing_source_content error”:

Frequently Asked Question

Sentry Flutter source maps can be a real puzzle, but don’t worry, we’ve got you covered! Here are some frequently asked questions and answers to help you troubleshoot those pesky errors.