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Blazer
Explore SQL data, build charts, and monitor alerts
Blazer adds SQL querying, charting, and alerting to Rails apps, supporting many databases, variable‑driven reports, audits, and flexible authentication.
Overview
Overview
Blazer is a Rails engine that lets developers run SQL queries against a variety of databases—PostgreSQL, MySQL, Redshift, and more—directly from their application. Queries can be parameterized with variables, and results are automatically visualized as line, bar, or pie charts, enabling fast insight without a separate BI tool.
Capabilities & Deployment
Beyond ad‑hoc reporting, Blazer supports scheduled checks that email or post to Slack when data anomalies appear, providing proactive data‑quality monitoring. Every query is audited and can be secured with basic auth, Devise, or custom before‑action hooks. Installation is a single gem line, a generator, and a route mount, with optional Docker images for containerized deployments. For production safety, it encourages read‑only database users and runs queries inside transactions that roll back any writes.
Highlights
Supports PostgreSQL, MySQL, Redshift and many other databases
Dynamic variables and smart variables for reusable queries
Scheduled checks with email or Slack alerts
Built‑in audit trail and permission system
Pros
- Integrates directly into Rails apps
- Rich visualization without extra front‑end
- Flexible authentication options
- Easy to schedule data quality checks
Considerations
- Limited to Ruby/Rails ecosystem
- Requires read‑only DB user for safety
- Complex configuration for advanced caching
- No native support for non‑SQL data sources
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Fit guide
Great for
- Data‑driven Rails teams needing internal dashboards
- Operations teams monitoring data quality
- Developers who want SQL‑based reporting without BI tools
- Small to medium apps that can host a Rails engine
Not ideal when
- Organizations requiring a standalone BI platform
- Teams using non‑SQL or NoSQL data stores exclusively
- Large enterprises needing granular role‑based access beyond Rails
- Users seeking out‑of‑the‑box cloud SaaS dashboards
How teams use it
Daily sales monitoring
Automated queries run every hour, charting sales trends and emailing alerts when revenue drops below threshold.
User activity cohort analysis
Variables let analysts slice activity by date range and segment, generating dashboards for product teams.
Data quality checks on ETL pipelines
Scheduled checks detect nulls or anomalies and post to Slack, enabling rapid issue resolution.
Ad‑hoc reporting for finance
Finance users run parameterized SQL queries with smart variables, instantly visualizing results in line or bar charts.
Tech snapshot
Ruby76%
HTML24%
Frequently asked questions
How do I install Blazer in a Rails project?
Add `gem "blazer"` to your Gemfile, run `rails generate blazer:install && rails db:migrate`, then mount `Blazer::Engine` in your routes.
Can I protect the dashboard with my existing authentication?
Yes. Use basic auth, Devise, or define a custom `before_action_method` in `config/blazer.yml` to enforce any logic.
What databases are supported?
Blazer works with PostgreSQL, MySQL, MariaDB, Redshift, and any other DB that Rails can connect to via a URL.
How are scheduled checks configured?
Run `rake blazer:run_checks SCHEDULE="5 minutes"` via cron, Heroku Scheduler, Solid Queue, or similar. Alerts can be emailed or sent to Slack.
Do queries modify data?
Blazer runs each query inside a transaction and rolls it back, but using a read‑only DB user is the safest approach.
Project at a glance
Active- Stars
- 4,760
- Watchers
- 4,760
- Forks
- 493
LicenseMIT
Repo age11 years old
Last commit2 weeks ago
Primary languageRuby
Last synced 12 hours ago