Skip to content

README.md

Latest commit

 

History

History
481 lines (363 loc) · 17.1 KB

README.md

File metadata and controls

481 lines (363 loc) · 17.1 KB
Raw

base_cli

base_cli is Base's small Python framework for writing command-line tools that feel consistent across Base and Base-supported projects.

It is intentionally thin. Click still owns argument parsing and command execution, while base_cli adds the Base-specific behavior every project CLI should get by default:

  • standard command options such as --debug, --quiet, --environment, --config, --keep-temp, and --log-file
  • structured logging to stderr and, by default, to a persistent per-run log file
  • Base project discovery through base_manifest.yaml
  • config loading with predictable precedence
  • per-run temp directories, persistent cache directories, and cleanup hooks
  • sensitive argument redaction in debug invocation logs
  • a command context object shared by command code and helper functions
  • test helpers built on Click's CliRunner

Design Goals

Base CLI tools should be easy to write, but not magical. A command should be explicitly registered, receive an explicit Context, and use standard Python functions instead of import-time side effects.

The package follows these rules:

  • Decorator-driven setup: commands opt in by creating an App and decorating a function.
  • Logs go to stderr: user-facing program output can stay on stdout, while logs remain redirectable and skippable.
  • Every run has a context: logs, paths, config, environment, manifest, and cleanup are available through one object.
  • No import-time filesystem writes: state directories are created only when a command runs.
  • Base-aware, Click-compatible: command authors keep using familiar Click concepts such as options and arguments.

Minimal Command

from __future__ import annotations

import base_cli


app = base_cli.App(name="hello", version="0.1.0")


@app.command()
@base_cli.option("--name", required=True)
def main(ctx: base_cli.Context, name: str) -> None:
    ctx.log.info("starting hello")
    print(f"hello {name}")


if __name__ == "__main__":
    raise SystemExit(base_cli.run_app(app))

Running this command directly as a Python package automatically adds the standard Base options:

hello --name Ada
hello --debug --name Ada
hello --quiet --name Ada
hello --environment prod --name Ada
hello --keep-temp --name Ada
hello --log-file /tmp/hello.log --name Ada

Long options with values use space-separated syntax. base_cli.run_app() rejects equals-form values such as --name=Ada before Click parses arguments. These are direct package options. Public basectl launchers expose -v for command-level debug logs and command-specific flags from basectl <command> --help; they do not expose --debug, --quiet, --log-file, --config, --environment, or --keep-temp as public basectl options.

Command Registration

Use App when you want a named command:

app = base_cli.App(name="base-projects", version="0.1.0")

Register the command function explicitly:

@app.command()
def main(ctx: base_cli.Context) -> None:
    ...

The command function always receives ctx as its first argument. User-defined options and arguments are passed after the Base standard options have been removed from Click's keyword arguments.

For small scripts, the module-level decorators are available:

@base_cli.command()
def main(ctx: base_cli.Context) -> None:
    ...

In Base itself, prefer an explicit App so command names and versions are obvious at the top of the module.

Use @app.subcommand() when one CLI needs multiple verbs while keeping Base's standard context, logging, redaction, and cleanup lifecycle for each invocation:

app = base_cli.App(
    name="workspace-tools",
    version="0.1.0",
    help="Inspect and sync workspace projects.",
)


@app.subcommand()
@base_cli.argument("project")
def status(ctx: base_cli.Context, project: str) -> None:
    ctx.log.info("checking %s", project)


@app.subcommand("sync")
@base_cli.option("--dry-run", is_flag=True)
def sync_project(ctx: base_cli.Context, dry_run: bool) -> None:
    if ctx.dry_run:
        ctx.log.info("previewing sync")

Subcommands use the same base_cli.option() and base_cli.argument() metadata as single commands. App(help=...) appears in the command group's --help output. For subcommand apps, prefer standard Base options before the subcommand name, for example workspace-tools --debug status demo. The post-subcommand form, such as workspace-tools status --debug demo, remains accepted for compatibility. Use either @app.command() for a single-command CLI or @app.subcommand() for a command group; do not mix the two registration styles on one App.

Options And Arguments

base_cli.option and base_cli.argument mirror Click's decorators:

@app.command()
@base_cli.argument("project")
@base_cli.option("--workspace", type=str)
def main(ctx: base_cli.Context, project: str, workspace: str | None) -> None:
    ...

Use sensitive=True for options whose values should not appear in invocation logs:

@base_cli.option("--token", sensitive=True, required=True)
def main(ctx: base_cli.Context, token: str) -> None:
    ...

Both --token secret and an externally supplied --token=secret token are redacted in debug logs, even though Base command invocation rejects equals-form option values before Click parses them.

Use dry_run=True when a nonstandard option should drive ctx.dry_run and Base's default durable-write suppression:

@base_cli.option("--preview", is_flag=True, dry_run=True)
def main(ctx: base_cli.Context, preview: bool) -> None:
    if ctx.dry_run:
        ctx.log.info("previewing changes")

The conventional dry_run parameter is recognized automatically, so commands using @base_cli.option("--dry-run", is_flag=True) do not need the marker. Only one option on a command may be marked dry_run=True; duplicate dry-run markers fail during command registration so authors do not accidentally ship an option that is ignored by ctx.dry_run.

Standard Options

Every base_cli.App command gets these options:

  • --debug: enable DEBUG logging on the user-facing stderr stream.
  • --quiet, -q: suppress INFO logs on the user-facing stderr stream.
  • --environment <name>: set ctx.environment for the run.
  • --config <path>: merge an additional YAML config file.
  • --keep-temp: preserve the run's temp directory after command completion.
  • --log-file <path>: write the persistent log to a specific file.
  • --version: shown when the App was created with a version.

The command receives only its own application-specific options. Standard options are consumed before the command function is called.

Exit Codes

Use base_cli.ExitCode when command code or tests need to name Base's standard command result meanings:

  • ExitCode.SUCCESS (0): the command completed successfully.
  • ExitCode.FAILURE (1): the command was valid, but an operational problem prevented successful completion.
  • ExitCode.USAGE_ERROR (2): the command could not proceed because user input, configuration, or environment setup was invalid or incomplete.

Existing commands can keep returning integers. New code should prefer the named constants when it makes intent clearer:

if ctx.project_root is None:
    ctx.log.error("run this command from a Base project")
    return base_cli.ExitCode.USAGE_ERROR

Context

Context is the object command code should pass around instead of rediscovering Base paths or global settings.

Important fields include:

  • ctx.cli_name: normalized CLI name used for state paths and logger names.
  • ctx.run_id: timestamp plus short random suffix for this invocation.
  • ctx.base_home: resolved BASE_HOME, when available.
  • ctx.project_root: directory containing the nearest base_manifest.yaml.
  • ctx.workspace_root: configured workspace root from ~/.base.d/config.yaml.
  • ctx.manifest_path: nearest discovered Base manifest.
  • ctx.state_dir: per-CLI runtime directory under the Base cache root.
  • ctx.log_dir: persistent log directory.
  • ctx.cache_dir: persistent cache directory.
  • ctx.temp_dir: per-run temp directory.
  • ctx.log_file: persistent log file for this run, or None when persistent logging is disabled.
  • ctx.config: merged configuration dictionary.
  • ctx.user_config: typed user configuration from ~/.base.d/config.yaml.
  • ctx.environment: active environment, defaulting to dev.
  • ctx.debug: whether debug logging is enabled for the stderr stream.
  • ctx.quiet: whether INFO logs are suppressed on the stderr stream.
  • ctx.dry_run: whether the command is running in a no-durable-write mode.
  • ctx.keep_temp: whether ctx.temp_dir should survive cleanup.
  • ctx.log: standard Python logger configured by Base.

Helpers can retrieve the active context without threading it through every call:

from base_cli import get_current_context


def helper() -> None:
    ctx = get_current_context()
    ctx.log.debug("helper is running")

get_current_context() is valid only while a base_cli.App command is running.

Logging

base_cli configures two handlers:

  • a user-facing stderr handler at INFO by default, DEBUG with --debug, or WARNING with --quiet / -q
  • a persistent file handler that records DEBUG logs when persistent logging is enabled

--quiet suppresses INFO output on the user-facing stream but still shows warnings and errors. --debug and --quiet cannot be used together. Persistent log files still receive DEBUG-level detail, including INFO messages suppressed from stderr.

Advanced tests and CI wrappers can call base_cli.configure_logger(..., stream=..., formatter=...) to capture user-facing logs or apply a custom formatter without replacing Base's logger setup. Leave those arguments as None to keep the default stderr stream and BaseCliFormatter.

Commands that inspect runtime artifacts can use base_cli.App(log_to_file=False) to keep the standard context, --debug, and --quiet behavior without creating default logs/, cache/, or tmp/<run-id>/ directories. base_logs uses this mode so basectl logs does not appear in its own output; base_history does the same for basectl history. An explicit --log-file <path> still enables file logging for that invocation.

Commands running with ctx.dry_run also skip default logs/, cache/, and tmp/<run-id>/ creation. Passing --log-file <path> still writes to that explicit file so tests and diagnostics can inspect dry-run logs when needed.

For Python-backed commands with persistent logs, base_cli.App also writes a best-effort final history record to <base-cache-root>/history/runs.jsonl. History records contain redacted command metadata, timing, exit status, project context when known, and a pointer to the raw log file. History writes are local only and do not fail the user command when the index cannot be updated.

High-frequency tools can set base_cli.App(max_log_files=<count>) to keep at most that many default persistent log files for the CLI. Retention runs during startup after the current run's default log file is resolved, and the current run's log file is never pruned. Default log pruning uses the timestamp-prefixed run ID in each log filename rather than filesystem modification time. The policy is skipped for ctx.dry_run, log_to_file=False, and explicit --log-file paths so no-durable-write modes and caller-selected log locations stay under caller control. Use this as a small guardrail for busy local tools; basectl clean remains the broader maintenance command for caches, logs, and retained temp files.

Logs use the same general shape as Base Bash logs:

2026-05-26 12:34:56 INFO    path/to/file.py:42 message

Use either ctx.log directly:

ctx.log.info("processed %s items", count)

or the convenience functions:

base_cli.log_debug("cache_dir=%s", ctx.cache_dir)
base_cli.log_info("done")
base_cli.log_warning("using fallback")
base_cli.log_error("failed")

Program output should still use stdout when another command might consume it. Logs should stay on stderr so users can redirect or ignore logs without losing the real command output.

Config Precedence

Configuration is loaded from YAML files and environment variables in this order:

  1. user config: ~/.base.d/config.yaml
  2. project config: <project>/.base/config.yaml
  3. explicit config from --config
  4. environment variables
  5. direct command-line standard options

Environment variables currently recognized by the config layer:

  • BASE_CLI_ENVIRONMENT
  • BASE_CLI_LOG_LEVEL
  • BASE_CLI_KEEP_TEMP

LOG_DEBUG=1 or LOG_DEBUG=true is also accepted as an internal compatibility fallback for wrapper/debug paths when BASE_CLI_LOG_LEVEL is unset. Prefer BASE_CLI_LOG_LEVEL=debug for user-facing Python CLI debug logging.

Command-line standard options are applied after config is loaded. For example, --environment prod overrides environment: dev from config.

ctx.config exposes the merged raw configuration after user, project, explicit, and environment layers are applied. ctx.user_config exposes only the typed machine-local user config, including workspace.root, workspace.manifest, and IDE preferences, so command code does not need to re-read ~/.base.d/config.yaml for those structured values.

The user config file is machine-local by default. Base owns the semantics of ~/.base.d/config.yaml, while users own backup and sync choices such as iCloud, chezmoi, dotfiles repositories, Time Machine, or manual copy. See docs/local-config.md for the product-level boundary.

Project Discovery

When a command runs, base_cli walks upward from the current working directory looking for base_manifest.yaml.

If found:

  • ctx.manifest_path points to the manifest
  • ctx.project_root points to the manifest's parent directory

If no manifest is found, both fields are None. Commands that require a Base project should validate this explicitly and return a clear usage error or actionable message.

Runtime Directories

On macOS, current runtime state is rooted at ~/Library/Caches/base:

~/Library/Caches/base/cli/<cli-name>/
  logs/
  cache/
  tmp/<run-id>/

On Linux and other non-macOS platforms, the default is ~/.cache/base. Use BASE_CACHE_DIR to override the root for tests, CI, or unusual local environments.

logs/ and cache/ are runtime artifacts that can be pruned with basectl clean --older-than <age>. Logs can also be pruned with basectl clean --keep-last <count>, which keeps the newest log files per CLI log directory. tmp/<run-id>/ is deleted automatically after the command returns unless --keep-temp is set; retained temp entries can also be pruned by basectl clean.

Use ctx.on_cleanup() for cleanup work that should happen even when helper code does not own the main command wrapper:

def close_connection() -> None:
    connection.close()


ctx.on_cleanup(close_connection)

Cleanup hooks run before temp directory removal. Hook failures are logged as warnings and do not prevent later hooks from running.

Testing

Use base_cli.testing.invoke for unit tests:

from pathlib import Path

from base_cli.testing import invoke


def test_command(tmp_path: Path) -> None:
    project = tmp_path / "project"
    project.mkdir()

    result = invoke(
        app,
        ["--name", "Ada"],
        home=tmp_path,
        cwd=project,
        manifest={"project": {"name": "demo"}, "artifacts": []},
    )

    assert result.exit_code == 0
    assert "hello Ada" in result.stdout

The helper wraps Click's CliRunner, sets HOME when requested, supplies cwd to Base's context discovery without mutating process-global cwd, and keeps stderr separate on Click versions that support it. Use cwd for commands whose behavior depends on project discovery, including tests that intentionally run outside a Base project. Pass manifest={...} with cwd to write a temporary base_manifest.yaml before the command runs.

When home is supplied, invoke() also defaults BASE_CACHE_DIR to <home>/.cache/base so helper-based tests do not inherit a developer's real cache root. Pass env={"BASE_CACHE_DIR": str(path)} when a test needs an explicit cache location.

When To Use base_cli

Use base_cli for Python commands that are part of Base or a Base-supported project and need standard Base behavior.

Base public command engines under cli/python/base_*/engine.py should instantiate base_cli.App so standard options, logging, redaction, runtime state, and local command history stay consistent. If a future public Python engine intentionally bypasses this lifecycle, document the reason in code and in this guide, then add it as an explicit lifecycle-audit exemption. Shell-only helpers that avoid Python startup, such as basectl config path, do not create Python logs or history records; once a basectl path enters a Python command package, it should participate in base_cli.App.

It is a good fit for:

  • project discovery commands
  • setup and artifact management commands
  • developer workflow commands
  • CLIs that need predictable logs, temp directories, and config precedence

It is not meant to replace Click, Typer, argparse, or rich terminal UI frameworks. It is the Base layer around command lifecycle, context, logging, configuration, and state.