Adding A CLI Command

Adding a new verdi CLI command

Steps

1. Create the command under src/aiida/cmdline/commands/, typically as part of an existing cmd_*.py file (cmd_process.py, cmd_calcjob.py, cmd_devel.py, etc.).
2. Use Click decorators plus AiiDA's custom decorators from aiida.cmdline.utils.decorators (e.g. @decorators.with_dbenv() for commands that need the storage backend loaded).
3. Register the command in the appropriate command group (usually via @<group>.command()).
4. Add tests in tests/cmdline/commands/.

Import-time constraint (CRITICAL)

verdi must load quickly even for verdi --help, so aiida.* imports inside src/aiida/cmdline/ must be deferred to inside the function body, not placed at module top level:

# WRONG - will break CI via verdi devel check-load-time
from aiida.orm import QueryBuilder

@cmd_something.command()
def my_command():
    qb = QueryBuilder()
    ...

# RIGHT
@cmd_something.command()
def my_command():
    from aiida.orm import QueryBuilder
    qb = QueryBuilder()
    ...

CI enforces this via verdi devel check-load-time, which fails if any module outside aiida.brokers, aiida.cmdline, aiida.common, aiida.manage, aiida.plugins, or aiida.restapi is imported at startup.

At the top level of a cmd_*.py file, only click, standard library, and the whitelisted aiida.* submodules listed above may be imported.

Reusable arguments and options

AiiDA provides a library of reusable, ALL_CAPS Click parameters in src/aiida/cmdline/params/: arguments (positional) and options (flags). Always check for an existing one before defining ad-hoc click.argument() / click.option() calls.

from aiida.cmdline.params import arguments, options

@verdi_process.command('show')
@arguments.PROCESSES()
@options.RAW()
def process_show(processes, raw):
    ...

Both are wrapped in OverridableArgument / OverridableOption classes that store defaults but allow per-command customization via .clone().

Relevant source

• Decorators: src/aiida/cmdline/utils/decorators.py
• Existing commands: src/aiida/cmdline/commands/cmd_*.py
• Reusable arguments: src/aiida/cmdline/params/arguments/main.py
• Reusable options: src/aiida/cmdline/params/options/main.py
• Custom option types: src/aiida/cmdline/params/options/{callable,conditional,interactive,multivalue,config}.py
• Parameter types (ParamType subclasses): src/aiida/cmdline/params/types/
• Load-time check implementation: src/aiida/cmdline/commands/cmd_devel.py (check-load-time)