feat: Run Terraform

Give Cally the ability to run terraform directly, so that there is no need to mess
around with outputs or stacks in the same directory conflicting with each other.

pyproject.toml

@@ -141,3 +141,7 @@ select = [
     "S404",  # `subprocess` module is possibly insecure - used for 'cdktf get'
     "S602"  # `subprocess` call with `shell=True` identified - required for 'cdktf get'
 ]
+"src/cally/cli/tools/terraform.py" = [
+    "S404",  # `subprocess` module is possibly insecure - used for 'terraform x'
+    "S603",  # `subprocess` call: check for execution of untrusted input - CLI wrapper is expected to take these inputs
+]

src/cally/cli/commands/tf.py

@@ -1,4 +1,6 @@
+import sys
 from pathlib import Path
+from typing import Tuple
 
 import click
 
@@ -32,5 +34,32 @@ def write_template(config: CallyStackServiceConfig, output: Path):
         click.secho(f'Template written to {output}')
 
 
+@click.command(
+    name='run',
+    cls=CallyStackServiceCommand(),
+    context_settings={'ignore_unknown_options': True},
+)
+@click.option(
+    '--terraform-path',
+    envvar='CALLY_TERRAFORM_PATH',
+    type=click.Path(file_okay=True, dir_okay=False, executable=True),
+    default='/usr/bin/terraform',
+    help='Path to the terraform binary',
+)
+@click.argument('args', nargs=-1, type=click.UNPROCESSED)
+@click.pass_obj
+def run_terraform(
+    config: CallyStackServiceConfig, terraform_path: str, args: Tuple[str, ...]
+):
+    tf_cmd = terraform.Command(terraform_path=terraform_path, arguments=args)
+    with terraform.Action(service=config.config) as action:
+        action.synth_stack()
+        if not tf_cmd.success:
+            click.secho(message=tf_cmd.stderr, fg='red')
+            sys.exit(tf_cmd.returncode)
+    click.secho(tf_cmd.stdout)
+
+
 tf.add_command(print_template)
+tf.add_command(run_terraform)
 tf.add_command(write_template)

src/cally/cli/tools/terraform.py

@@ -3,7 +3,7 @@
 from pathlib import Path
 from tempfile import TemporaryDirectory
 from types import TracebackType
-from typing import List, Type
+from typing import Tuple, Type
 
 from cally.cdk import stacks
 
@@ -57,20 +57,19 @@ def print(self) -> str:
 
 
 class Command:
-    arguments: List[str]
+    arguments: Tuple[str, ...]
     terraform_path: str
-    _result = subprocess.CompletedProcess
+    _result: subprocess.CompletedProcess
 
-    def __init__(self, terraform_path: str, arguments: List[str]) -> None:
+    def __init__(self, terraform_path: str, arguments: Tuple[str, ...]) -> None:
         self.terraform_path = terraform_path
         self.arguments = arguments
 
     @property
     def result(self) -> subprocess.CompletedProcess:
         if getattr(self, '_result', None) is None:
-            arguments = ' '.join(self.arguments)
             self._result = subprocess.run(
-                command=f'{self.terraform_path} {arguments}',
+                args=[self.terraform_path, *self.arguments],
                 capture_output=True,
                 check=False,
             )