Using Config Files

Typing in command-line options with every invocation of Harlequin can get tiring. Instead, you can create profiles (sets of configurations) and save those profiles to a config file, which Harlequin will discover and load automatically.

Harlequin also provides a tool for creating and editing profiles. For more information, see below.

Config File Discovery

Harlequin loads config files from the following locations. If it finds multiple files, it merges them, with items listed first taking priority:

  1. The file located at the path provided by the --config-path CLI option (see below).
  2. Files named harlequin.toml, .harlequin.toml, or pyproject.toml in the current working directory.
  3. Files named harlequin.toml, .harlequin.toml, or config.toml in the user’s default config directory, in the harlequin subdirectory. For example:
    • Linux: $XDG_CONFIG_HOME/harlequin/config.toml or ~/.config/harlequin/config.toml
    • Mac: ~/Library/Application Support/harlequin/config.toml
    • Windows: ~\AppData\Local\harlequin\config.toml
  4. Files named harlequin.toml, .harlequin.toml, or pyproject.toml in the user’s home directory (~).

Custom Config Path

You can specify a custom path to a config file by invoking Harlequin with the --config-path option:

$ harlequin --config-path /path/to/my/file.toml

Selecting a Profile

To load Harlequin with the config from a profile, invoke Harlequin with the --profile option (alias -P):

$ harlequin --profile my-profile

Config files can also define a default profile. To override the default profile and run Harlequin without any values from its config files, invoke Harlequin with the special profile named None:

$ harlequin --profile None

Creating and Updating Config Files

You can create config files manually, using any text editor. However, Harlequin can help make that process easier with its config wizard. To launch the wizard, run Harlequin with the --config option:

$ harlequin --config

Harlequin will then prompt you for the path to the config file to generate or edit, the name of the profile to create or update, and to provide values for all available options.

Example of the config wizard.
Example of the config wizard.

Config File Schema

Config files are written in TOML.

Config files define one or more profiles, which contain keys that map to Harlequin options or adapter options. Each profile is a TOML table with the key [profiles.<profile-name>].

Config files may also define a default profile, which Harlequin will automatically load if invoked without the --profile option.

For example, this is a valid config file:

default_profile = "my-duckdb-profile"

limit = 200_000
adapter = "duckdb"
conn_str = ["my-database.db"]
read_only = true
extension = ["httpfs", "spatial"]
init_path = "~/.duckdbrc"

theme = "fruity"
limit = 10_000
adapter = "postgres"
host = "localhost"
user = "postgres"
password = "secretadminpassword"
dbname = "postgres"
port = 5432

Using pyproject.toml

If configuring Harlequin using pyproject.toml, you must nest the above config under the tool.harlequin table. An example pyproject.toml file:

default_profile = "my-duckdb-profile"

limit = 200_000
conn_str = ["my-database.db"]

theme = "fruity"
limit = 10_000

Option names

To view a list of available options (including options for your installed adapters), run harlequin --help.

The names of options in the config file are the snake_case version of the command-line option. For example, the command-line option --read-only becomes read_only in the config file.