# Environment Variables

For each Meltano installation, if you need to customize environment variables, this is done with the .env file that is created with each new installation.

# Anonymous Usage Data

By default, Meltano shares anonymous usage data with the Meltano team using Google Analytics. We use this data to learn about the size of our user base and the specific Meltano features they are (not yet) using, which helps us determine the highest impact changes we can make in each weekly release to make Meltano even more useful for you and others like you.

If you'd prefer to use Meltano without sending the team this kind of data, you can disable tracking entirely using one of these methods:

• When creating a new project, pass --no_usage_stats to meltano init:

  meltano init PROJECT_NAME --no_usage_stats
  

• In an existing project, disable the send_anonymous_usage_stats setting in the meltano.yml file:

  send_anonymous_usage_stats: false
  

• To disable tracking in all projects in one go, set the MELTANO_DISABLE_TRACKING environment variable to True:

  # Add to `~/.bashrc`, `~/.zshrc`, etc, depending on the shell you use:
  export MELTANO_DISABLE_TRACKING=True
  

When anonymous usage tracking is enabled, Meltano tracks the following events:

• meltano init {project name}
• meltano ui
• meltano elt {extractor} {loader} --transform {skip, only, run}
• meltano add {extractor, loader, transform, model, transformer, orchestrator}
• meltano discover {all, extractors, loaders, transforms, models, transformers, orchestrators}
• meltano install
• meltano invoke {plugin_name} {plugin_args}
• meltano select {extractor} {entities_filter} {attributes_filter}
• meltano schedule add {name} {extractor} {loader} {interval}
• meltano permissions grant --db {postgres, snowflake} --dry

Beyond the invocation of these commands and the identified command line arguments, Meltano does not track any other event metadata, plugin configuration, or processed data.

Finally, Meltano also tracks anonymous web metrics when browsing the Meltano UI pages.

If you want to evaluate Meltano's anonymous usage tracking strategy for yourself, you can check meltano.core.tracking.GoogleAnalyticsTracker and all the places that it is used.

# Connector Settings Configuration

Until role-based access control is implemented in Meltano, we need to prevent user editing of certain settings from the UI. View this tap-gitlab environment variable setup example to learn how to work with this current limitation.

# System Database

By default, Meltano uses a SQLite database named ./meltano/meltano.db as its system database.

You can choose to use a different system database backend or configuration using the --database-uri option of the meltano command, or the MELTANO_DATABASE_URI environment variable:

# SQLite (absolute path required, notice the `3` slashes before the path)
export MELTANO_DATABASE_URI=sqlite:////path/to/system_database.db
# PostgreSQL:
export MELTANO_DATABASE_URI=postgresql://username:password@host:port/database

# Flask

The following are the environment variables currently available for customization for Flask.

Update your .env file in your project directory with the desired customizations.

export FLASK_PROFILE = ""
export FLASK_ENV = ""

# AuthLib

These variables are specific to Flask-OAuthlib and work with OAuth authentication with GitLab.

Update your .env file in your project directory with the desired customizations.

# GitLab Client ID
export OAUTH_GITLAB_APPLICATION_ID = ""
# GitLab Client Secret
export OAUTH_GITLAB_SECRET = ""

For more information on how to get these from your GitLab application, check out the integration docs from GitLab.

# Service Listen Configuration

By default, the API and Airflow services listen with following host/port combinations.

API: http://0.0.0.0:5000 Airflow: http://0.0.0.0:5010

To change the host/port configuration on which the API or Airflow server listen, update your .env in your project directory with the following configuration:

# Meltano API configuration
export MELTANO_API_HOSTNAME="0.0.0.0"
export MELTANO_API_PORT="5000"

# Airflow configuration
export AIRFLOW__WEBSERVER__WEB_SERVER_HOST="0.0.0.0"
export AIRFLOW__WEBSERVER__WEB_SERVER_PORT="5010"