Explore your data with SQL. Easily create charts and dashboards, and share them with your team.
Blazer is also available as a Docker image.
🍊 Battle-tested at Instacart
- Multiple data sources - PostgreSQL, MySQL, Redshift, and many more
- Variables - run the same queries with different values
- Checks & alerts - get emailed when bad data appears
- Audits - all queries are tracked
- Security - works with your authentication system
Add this line to your application’s Gemfile:
gem 'blazer'
Run:
rails generate blazer:install
rails db:migrate
And mount the dashboard in your config/routes.rb
:
mount Blazer::Engine, at: "blazer"
For production, specify your database:
ENV["BLAZER_DATABASE_URL"] = "postgres://user:password@hostname:5432/database"
Blazer tries to protect against queries which modify data (by running each query in a transaction and rolling it back), but a safer approach is to use a read only user. See how to create one.
Be sure to set a host in config/environments/production.rb
for emails to work.
config.action_mailer.default_url_options = {host: "blazer.dokkuapp.com"}
Schedule checks to run (with cron, Heroku Scheduler, etc). The default options are every 5 minutes, 1 hour, or 1 day, which you can customize. For each of these options, set up a task to run.
rake blazer:run_checks SCHEDULE="5 minutes"
rake blazer:run_checks SCHEDULE="1 hour"
rake blazer:run_checks SCHEDULE="1 day"
You can also set up failing checks to be sent once a day (or whatever you prefer).
rake blazer:send_failing_checks
Here’s what it looks like with cron.
*/5 * * * * rake blazer:run_checks SCHEDULE="5 minutes"
0 * * * * rake blazer:run_checks SCHEDULE="1 hour"
30 7 * * * rake blazer:run_checks SCHEDULE="1 day"
0 8 * * * rake blazer:send_failing_checks
For Slack notifications, create an incoming webhook and set:
BLAZER_SLACK_WEBHOOK_URL=https://hooks.slack.com/...
Name the webhook “Blazer” and add a cool icon.
Don’t forget to protect the dashboard in production.
Set the following variables in your environment or an initializer.
ENV["BLAZER_USERNAME"] = "andrew"
ENV["BLAZER_PASSWORD"] = "secret"
authenticate :user, ->(user) { user.admin? } do
mount Blazer::Engine, at: "blazer"
end
Specify a before_action
method to run in blazer.yml
.
before_action_method: require_admin
You can define this method in your ApplicationController
.
def require_admin
# depending on your auth, something like...
redirect_to root_path unless current_user && current_user.admin?
end
Be sure to render or redirect for unauthorized users.
Blazer runs each query in a transaction and rolls it back to prevent queries from modifying data. As an additional line of defense, we recommend using a read only user.
Create a user with read only permissions:
BEGIN;
CREATE ROLE blazer LOGIN PASSWORD 'secret123';
GRANT CONNECT ON DATABASE database_name TO blazer;
GRANT USAGE ON SCHEMA public TO blazer;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO blazer;
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO blazer;
COMMIT;
Create a user with read only permissions:
GRANT SELECT, SHOW VIEW ON database_name.* TO blazer@’127.0.0.1′ IDENTIFIED BY ‘secret123‘;
FLUSH PRIVILEGES;
Create a user with read only permissions:
db.createUser({user: "blazer", pwd: "password", roles: ["read"]})
Also, make sure authorization is enabled when you start the server.
If your database contains sensitive or personal data, check out Hypershield to shield it.
If you need to search encrypted data, use blind indexing.
You can have Blazer transform specific variables with:
Blazer.transform_variable = lambda do |name, value|
value = User.compute_email_bidx(value) if name == "email_bidx"
value
end
Create queries with variables.
SELECT * FROM users WHERE gender = {gender}
Use {start_time}
and {end_time}
for time ranges. Example
SELECT * FROM ratings WHERE rated_at >= {start_time} AND rated_at <= {end_time}
Suppose you have the query:
SELECT * FROM users WHERE occupation_id = {occupation_id}
Instead of remembering each occupation’s id, users can select occupations by name.
Add a smart variable with:
smart_variables:
occupation_id: "SELECT id, name FROM occupations ORDER BY name ASC"
The first column is the value of the variable, and the second column is the label.
You can also use an array or hash for static data and enums.
smart_variables:
period: ["day", "week", "month"]
status: {0: "Active", 1: "Archived"}
Example - title column
Link results to other pages in your apps or around the web. Specify a column name and where it should link to. You can use the value of the result with {value}
.
linked_columns:
user_id: "/admin/users/{value}"
ip_address: "https://www.infosniper.net/index.php?ip_address={value}"
Example - occupation_id column
Suppose you have the query:
SELECT name, city_id FROM users
See which city the user belongs to without a join.
smart_columns:
city_id: "SELECT id, name FROM cities WHERE id IN {value}"
You can also use a hash for static data and enums.
smart_columns:
status: {0: "Active", 1: "Archived"}
Blazer can automatically cache results to improve speed. It can cache slow queries:
cache:
mode: slow
expires_in: 60 # min
slow_threshold: 15 # sec
Or it can cache all queries:
cache:
mode: all
expires_in: 60 # min
Of course, you can force a refresh at any time.
Blazer will automatically generate charts based on the types of the columns returned in your query.
Note: The order of columns matters.
There are two ways to generate line charts.
2+ columns - timestamp, numeric(s) - Example
SELECT date_trunc('week', created_at), COUNT(*) FROM users GROUP BY 1
3 columns - timestamp, string, numeric - Example
SELECT date_trunc('week', created_at), gender, COUNT(*) FROM users GROUP BY 1, 2
There are also two ways to generate column charts.
2+ columns - string, numeric(s) - Example
SELECT gender, COUNT(*) FROM users GROUP BY 1
3 columns - string, string, numeric - Example
SELECT gender, zip_code, COUNT(*) FROM users GROUP BY 1, 2
2 columns - both numeric - Example
SELECT x, y FROM table
2 columns - string, numeric - and last column named pie
- Example
SELECT gender, COUNT(*) AS pie FROM users GROUP BY 1
Columns named latitude
and longitude
or lat
and lon
or lat
and lng
- Example
SELECT name, latitude, longitude FROM cities
To enable, get an access token from Mapbox and set ENV["MAPBOX_ACCESS_TOKEN"]
.
Use the column name target
to draw a line for goals. Example
SELECT date_trunc('week', created_at), COUNT(*) AS new_users, 100000 AS target FROM users GROUP BY 1
Create a dashboard with multiple queries. Example
If the query has a chart, the chart is shown. Otherwise, you’ll see a table.
If any queries have variables, they will show up on the dashboard.
Checks give you a centralized place to see the health of your data. Example
Create a query to identify bad rows.
SELECT * FROM ratings WHERE user_id IS NULL /* all ratings should have a user */
Then create check with optional emails if you want to be notified. Emails are sent when a check starts failing, and when it starts passing again.
Blazer supports two different approaches to anomaly detection.
Trend is easiest to set up but uses an external service.
Add trend to your Gemfile:
gem 'trend'
And add to config/blazer.yml
:
anomaly_checks: trend
R is harder to set up but doesn’t use an external service. It uses Twitter’s AnomalyDetection library.
First, install R. Then, run:
install.packages("remotes")
remotes::install_github("twitter/AnomalyDetection")
And add to config/blazer.yml
:
anomaly_checks: r
If upgrading from version 1.4 or below, also follow the upgrade instructions.
If you’re on Heroku, follow these additional instructions.
Blazer has experimental support for forecasting through Trend.
Add trend to your Gemfile:
gem 'trend'
And add to config/blazer.yml
:
forecasting: trend
A forecast link will appear for queries that return 2 columns with types timestamp and numeric.
Blazer supports multiple data sources 🎉
Add additional data sources in config/blazer.yml
:
data_sources:
main:
url: <%= ENV["BLAZER_DATABASE_URL"] %>
# timeout, smart_variables, linked_columns, smart_columns
catalog:
url: <%= ENV["CATALOG_DATABASE_URL"] %>
# ...
redshift:
url: <%= ENV["REDSHIFT_DATABASE_URL"] %>
# ...
- Amazon Athena
- Amazon Redshift
- Apache Drill
- Cassandra
- Druid
- Elasticsearch
- Google BigQuery
- IBM DB2 and Informix
- MongoDB
- MySQL
- Neo4j
- Oracle
- PostgreSQL
- Presto
- Salesforce
- Socrata Open Data API (SODA)
- Snowflake
- SQLite
- SQL Server
You can also create an adapter for any other data store.
Note: In the examples below, we recommend using environment variables for urls.
data_sources:
my_source:
url: <%= ENV["BLAZER_MY_SOURCE_URL"] %>
Add aws-sdk-athena and aws-sdk-glue to your Gemfile and set:
data_sources:
my_source:
adapter: athena
database: database
output_location: s3://some-bucket/
Add activerecord4-redshift-adapter or activerecord5-redshift-adapter to your Gemfile and set:
data_sources:
my_source:
url: redshift://user:password@hostname:5439/database
Add drill-sergeant to your Gemfile and set:
data_sources:
my_source:
adapter: drill
url: http://hostname:8047
Add cassandra-driver to your Gemfile and set:
data_sources:
my_source:
url: cassandra://user:password@hostname:9042/keyspace
Enable SQL support on the broker and set:
data_sources:
my_source:
adapter: druid
url: http://hostname:8082
Add elasticsearch and elasticsearch-xpack to your Gemfile and set:
data_sources:
my_source:
adapter: elasticsearch
url: http://user:password@hostname:9200
Add google-cloud-bigquery to your Gemfile and set:
data_sources:
my_source:
adapter: bigquery
project: your-project
keyfile: path/to/keyfile.json
Use ibm_db.
Add mongo to your Gemfile and set:
data_sources:
my_source:
url: mongodb://user:password@hostname:27017/database
Add mysql2 to your Gemfile (if it’s not there) and set:
data_sources:
my_source:
url: mysql2://user:password@hostname:3306/database
Experimental
Add neo4j-core to your Gemfile and set:
data_sources:
my_source:
adapter: neo4j
url: http://user:password@hostname:7474
Use activerecord-oracle_enhanced-adapter.
Add pg to your Gemfile (if it’s not there) and set:
data_sources:
my_source:
url: postgres://user:password@hostname:5432/database
Add presto-client to your Gemfile and set:
data_sources:
my_source:
url: presto://user@hostname:8080/catalog
Experimental
Add restforce to your Gemfile and set:
data_sources:
my_source:
adapter: salesforce
And set the appropriate environment variables:
SALESFORCE_USERNAME="username"
SALESFORCE_PASSWORD="password"
SALESFORCE_SECURITY_TOKEN="security token"
SALESFORCE_CLIENT_ID="client id"
SALESFORCE_CLIENT_SECRET="client secret"
SALESFORCE_API_VERSION="41.0"
Supports SOQL
Experimental [master]
Set:
data_sources:
my_source:
adapter: soda
url: https://soda.demo.socrata.com/resource/4tka-6guv.json
app_token: ...
Supports SoQL
First, install ODBC. For Homebrew, use:
brew install unixodbc
For Ubuntu, use:
sudo apt-get install unixodbc-dev
For Heroku, use the Apt buildpack and create an Aptfile
with:
unixodbc-dev
https://sfc-repo.snowflakecomputing.com/odbc/linux/2.19.16/snowflake-odbc-2.19.16.x86_64.deb
This installs the driver at
/app/.apt/usr/lib/snowflake/odbc/lib/libSnowflake.so
Then, download the Snowflake ODBC driver. Add odbc_adapter to your Gemfile and set:
data_sources:
my_source:
adapter: snowflake
conn_str: Driver=/path/to/libSnowflake.so;uid=user;pwd=password;server=host.snowflakecomputing.com
Add sqlite3 to your Gemfile and set:
data_sources:
my_source:
url: sqlite3:path/to/database.sqlite3
Add tiny_tds and activerecord-sqlserver-adapter to your Gemfile and set:
data_sources:
my_source:
url: sqlserver://user:password@hostname:1433/database
Create an adapter for any data store with:
class FooAdapter < Blazer::Adapters::BaseAdapter
# code goes here
end
Blazer.register_adapter "foo", FooAdapter
See the Presto adapter for a good example. Then use:
data_sources:
my_source:
adapter: foo
url: http://user:password@hostname:9200/
Blazer supports a basic permissions model.
- Queries without a name are unlisted
- Queries whose name starts with
#
are only listed to the creator - Queries whose name starts with
*
can only be edited by the creator
Have team members who want to learn SQL? Here are a few great, free resources.
For an easy way to group by day, week, month, and more with correct time zones, check out Groupdate.sql.
Looking for a standalone version? Check out Ghost Blazer.
By default, queries take up a request while they are running. To run queries asynchronously, add to your config:
async: true
Note: Requires Rails 5+ and caching to be enabled. If you have multiple web processes, your app must use a centralized cache store like Memcached or Redis.
config.cache_store = :mem_cache_store
Add the R buildpack to your app.
heroku buildpacks:add --index 1 https://github.com/virtualstaticvoid/heroku-buildpack-r.git\#cedar-14
And create an init.r
with:
if (!"AnomalyDetection" %in% installed.packages()) {
install.packages("devtools")
devtools::install_github("twitter/AnomalyDetection")
}
Commit and deploy away. The first deploy may take a few minutes.
If views are stuck with a Loading...
message, there might be a problem with strict CSP settings in your app. This can be checked with Firefox or Chrome dev tools. You can allow Blazer to override these settings for its controllers with:
override_csp: true
To use Slack notifications, create a migration
rails g migration add_slack_channels_to_blazer_checks
with:
add_column :blazer_checks, :slack_channels, :text
To take advantage of the anomaly detection, create a migration
rails g migration upgrade_blazer_to_1_5
with:
add_column :blazer_checks, :check_type, :string
add_column :blazer_checks, :message, :text
commit_db_transaction
Blazer::Check.reset_column_information
Blazer::Check.where(invert: true).update_all(check_type: "missing_data")
Blazer::Check.where(check_type: nil).update_all(check_type: "bad_data")
To take advantage of the latest features, create a migration
rails g migration upgrade_blazer_to_1_3
with:
add_column :blazer_dashboards, :creator_id, :integer
add_column :blazer_checks, :creator_id, :integer
add_column :blazer_checks, :invert, :boolean
add_column :blazer_checks, :schedule, :string
add_column :blazer_checks, :last_run_at, :timestamp
commit_db_transaction
Blazer::Check.update_all schedule: "1 hour"
Blazer 1.0 brings a number of new features:
- multiple data sources, including Redshift
- dashboards
- checks
To upgrade, run:
bundle update blazer
Create a migration
rails g migration upgrade_blazer_to_1_0
with:
add_column :blazer_queries, :data_source, :string
add_column :blazer_audits, :data_source, :string
create_table :blazer_dashboards do |t|
t.text :name
t.timestamps
end
create_table :blazer_dashboard_queries do |t|
t.references :dashboard
t.references :query
t.integer :position
t.timestamps
end
create_table :blazer_checks do |t|
t.references :query
t.string :state
t.text :emails
t.timestamps
end
And run:
rails db:migrate
Update config/blazer.yml
with:
# see https://github.com/ankane/blazer for more info
data_sources:
main:
url: <%= ENV["BLAZER_DATABASE_URL"] %>
# statement timeout, in seconds
# applies to PostgreSQL only
# none by default
# timeout: 15
# time to cache results, in minutes
# can greatly improve speed
# none by default
# cache: 60
# wrap queries in a transaction for safety
# not necessary if you use a read-only user
# true by default
# use_transaction: false
smart_variables:
# zone_id: "SELECT id, name FROM zones ORDER BY name ASC"
linked_columns:
# user_id: "/admin/users/{value}"
smart_columns:
# user_id: "SELECT id, name FROM users WHERE id IN {value}"
# create audits
audit: true
# change the time zone
# time_zone: "Pacific Time (US & Canada)"
# class name of the user model
# user_class: User
# method name for the current user
# user_method: current_user
# method name for the display name
# user_name: name
# email to send checks from
# from_email: [email protected]
View the changelog
Blazer uses a number of awesome open source projects, including Rails, Vue.js, jQuery, Bootstrap, Selectize, StickyTableHeaders, Stupid jQuery Table Sort, and Date Range Picker.
Demo data from MovieLens.
That’s awesome! Here are a few ways you can help:
- Report bugs
- Fix bugs and submit pull requests
- Write, clarify, or fix documentation
- Suggest or add new features
Check out the dev app to get started.