Superset: Customize Database Error Messages For Better UX

Nov 6, 2025 by Admin 58 views

Introduction

Hey guys! Have you ever been stumped by those cryptic database error messages in Superset? You're not alone! This article dives into a cool feature that lets you customize those messages, making them user-friendly and way less confusing. We're talking about the CUSTOM_DATABASE_ERRORS configuration, a game-changer for improving user experience and reducing the support burden on you, the awesome admin. So, buckle up, and let's get started!

The Motivation Behind Custom Error Messages

Let's face it: raw database exception messages are often the bane of a user's existence. Imagine a user innocently trying to run a query in SQL Lab or load a chart, only to be greeted by a wall of technical jargon. Not a great experience, right? These messages, while informative to developers, are often cryptic, technical, and utterly unhelpful for the average user. This is where the motivation for a configurable system comes in. A system that can transform these raw, unfriendly database errors into custom, user-friendly messages. This would empower Superset administrators to tailor error messages to specific database connections, providing context-specific guidance when database errors occur. This not only drastically improves the user experience but also significantly reduces the support burden on the IT and data teams. Think about it: fewer confused users asking for help, and more time for you to focus on building awesome dashboards and insights. Moreover, this customization allows organizations to inject their own branding and tone into the error messages, creating a more cohesive and professional user experience. All in all, custom database error messages are a win-win for everyone involved. It's about making Superset more accessible, more user-friendly, and ultimately, more valuable to the organization.

Understanding the Current Behavior

Currently, when database errors occur in Superset, whether it's in SQL Lab or while loading charts, users are presented with the raw exception message directly from the database engine. These messages are displayed as-is, without any form of customization. This means that users are often left scratching their heads, trying to decipher complex error codes and technical terms that are completely foreign to them. This lack of customization can lead to frustration, confusion, and ultimately, a negative experience with Superset. Imagine a scenario where a user accidentally tries to query a table that doesn't exist. Instead of seeing a friendly message like "Oops! The table you're looking for doesn't seem to be here. Please check the table name and try again," they are greeted with a cryptic error message like "SQLAlchemyError: (psycopg2.errors.UndefinedTable) relation "non_existing_table" does not exist." Not very helpful, is it? This is why the ability to customize these error messages is so crucial. It allows administrators to bridge the gap between the technical details of the database and the user's understanding, making Superset a more accessible and user-friendly platform for everyone. By providing clear, concise, and context-specific error messages, we can empower users to troubleshoot issues themselves, reducing the reliance on support teams and improving overall productivity. Ultimately, it's about creating a more intuitive and empowering experience for all Superset users.

To reproduce the current behavior:

Navigate to SQL Lab in Superset.
Connect to any database (e.g., the "examples" database).
Execute a query that will intentionally fail: SELECT * FROM non_existing_table
Observe that the error message displayed is the raw database exception, devoid of any customization options.

Expected Behavior with Custom Error Messages

The goal is to equip Superset with a robust configuration system, aptly named CUSTOM_DATABASE_ERRORS, that empowers administrators to define custom error messages tailored to specific database errors. This system should be versatile and comprehensive, offering the following key functionalities:

Regex Pattern Matching: The system should be able to match database errors using regular expression (regex) patterns. This allows for flexible and precise identification of specific error scenarios.
Customizable Error Messages: When a regex pattern matches a database error, the system should replace the raw error message with a custom, user-friendly text. This is where the magic happens, transforming cryptic jargon into understandable guidance.
Dynamic Message Interpolation: Support for regex capture groups is essential. This allows for dynamic message interpolation, where parts of the original error message can be extracted and included in the custom message, providing context-specific information.
Optional "See More" Button Control: An option to hide the default "See more" button, which often displays technical issue codes, should be provided. This allows administrators to control the level of detail presented to the user, hiding potentially confusing technical information.
Cross-Context Applicability: The system should work seamlessly across all database error contexts within Superset, including SQL Lab, chart loading, and database validation.
Per-Database Configuration: The ability to configure different messages for different database connections is crucial. This allows for tailored error messages based on the specific characteristics and requirements of each database.

In essence, the expected behavior is a system that intelligently intercepts database errors, analyzes them, and presents users with clear, concise, and helpful messages that guide them towards resolution. This transforms error messages from roadblocks into stepping stones, empowering users to troubleshoot issues and continue their data exploration journey.

Acceptance Criteria:

[ ] A CUSTOM_DATABASE_ERRORS configuration can be defined in superset_config.py or a dedicated configuration file.
[ ] Custom error messages are displayed instead of raw database exceptions when a regex pattern matches.
[ ] The "See more" button with issue codes can be hidden when show_issue_info is set to False.
[ ] The configuration supports regex capture groups for dynamic message content.
[ ] The system works for errors in SQL Lab, chart execution, and database connection validation.
[ ] All existing tests pass and new tests cover the custom error functionality.

Steps to Test the Custom Error Configuration

Alright, let's get our hands dirty and test this awesome feature! Follow these steps to see the custom error configuration in action:

Add a Custom Error Configuration:

Open your superset_config.py file (or a dedicated configuration file) and add the following configuration:
```
import re
from flask_babel import gettext as __
from superset.errors import SupersetErrorType

CUSTOM_DATABASE_ERRORS = {
    "examples": {
        re.compile("no such table"): (
            __("The table you're trying to access doesn't exist"),
            SupersetErrorType.GENERIC_DB_ENGINE_ERROR,
            {
                "custom_doc_links": [
                    {
                        "url": "https://example.com/docs/tables",
                        "label": "View available tables"
                    }
                ],
                "show_issue_info": False,
            }
        )
    }
}
```
Explanation:
- "examples": This specifies that the configuration applies to the database connection named "examples". You can have different configurations for different databases.
- re.compile("no such table"): This is a regular expression that will match any error message containing the text "no such table".
- __("The table you're trying to access doesn't exist"): This is the custom error message that will be displayed to the user. The __ function is used for internationalization (i18n).
- SupersetErrorType.GENERIC_DB_ENGINE_ERROR: This specifies the type of error. You can choose from various error types defined in superset.errors.
- {"custom_doc_links": [...], "show_issue_info": False}: This is a dictionary containing additional options. In this case, we're adding a custom documentation link and hiding the "See more" button.
Restart Superset:

Restart your Superset instance to load the new configuration. This is crucial for the changes to take effect.
Execute a Failing Query in SQL Lab:

Navigate to SQL Lab in Superset and execute the following query:
```
SELECT * FROM non_existing_table
```
This query will intentionally fail because the table "non_existing_table" does not exist.
Verify the Custom Error Message:

Check that the custom error message "The table you're trying to access doesn't exist" appears instead of the raw database error.
Verify the "See More" Button:

Confirm that the "See more" button with issue codes is NOT displayed, as we set show_issue_info to False in the configuration.
Test with show_issue_info: True:

Modify the configuration to set show_issue_info to True and restart Superset. Verify that the "See more" button now appears.
Test with Capture Groups:

Let's get a bit more advanced and test with capture groups. Modify the configuration to the following:
```
import re
from flask_babel import gettext as __
from superset.errors import SupersetErrorType

CUSTOM_DATABASE_ERRORS = {
    "examples": {
        re.compile("table '(.*?)' does not exist"): (
            __("The table '%(table_name)s' you're trying to access doesn't exist"),
            SupersetErrorType.GENERIC_DB_ENGINE_ERROR,
            {
                "custom_doc_links": [
                    {
                        "url": "https://example.com/docs/tables",
                        "label": "View available tables"
                    }
                ],
                "show_issue_info": False,
                "table_name": r"\1",
            }
        )
    }
}
```
Explanation:
- re.compile("table '(.*?)' does not exist"): This regex now includes a capture group (.*?) to capture the table name.
- "table_name": r"\1": References the first capture group in the regex.
- __("The table '%(table_name)s' you're trying to access doesn't exist"): This custom message now includes a placeholder %(table_name)s that will be replaced with the captured table name.
Restart Superset and execute a query that will trigger this error. Verify that the custom message now includes the table name in the error message.

By following these steps, you can thoroughly test the custom error configuration and ensure that it's working as expected.

Conclusion

Custom database error messages are a powerful tool for enhancing the user experience in Superset. By transforming cryptic error messages into user-friendly guidance, we can empower users to troubleshoot issues themselves and reduce the burden on support teams. The CUSTOM_DATABASE_ERRORS configuration provides a flexible and comprehensive system for tailoring error messages to specific database connections, allowing organizations to create a more accessible, intuitive, and valuable data exploration platform. So go ahead, give it a try, and make Superset even better for your users! Happy data exploring, guys!