more well-defined CLI with custom mutable context

kiwi_scp/commands/cli.py

@@ -1,20 +1,45 @@
 import os
+from pathlib import Path
 
+import attr
 import click
 
+from ..config import Config
+
 
 class KiwiCLI(click.MultiCommand):
+    """Command Line Interface spread over multiple files in this directory"""
+
     def list_commands(self, ctx):
-        result = []
-        for filename in os.listdir(os.path.abspath(os.path.dirname(__file__))):
-            if filename.startswith("cmd_") and filename.endswith(".py"):
-                result.append(filename[4:-3])
-        result.sort()
-        return result
+        """list all the commands defined by cmd_*.py files in this directory"""
+
+        return (
+            filename[4:-3]
+            for filename in os.listdir(os.path.abspath(os.path.dirname(__file__)))
+            if filename.startswith("cmd_") and filename.endswith(".py")
+        )
 
     def get_command(self, ctx, name):
+        """import and return a specific command"""
+
         try:
             mod = __import__(f"kiwi_scp.commands.cmd_{name}", None, None, ["cmd"])
         except ImportError:
             return
         return mod.cmd
+
+
+@attr.s
+class KiwiCTX:
+    """this class is used as the commands' shared context"""
+
+    instance: Path = attr.ib(factory=lambda: Path('.'))
+
+    @property
+    def config(self) -> Config:
+        """shorthand: get the current configuration"""
+
+        return Config.from_instance(self.instance)
+
+
+pass_kiwi_ctx = click.make_pass_decorator(KiwiCTX, ensure=True)

kiwi_scp/commands/cmd_init.py

@@ -1,21 +1,20 @@
 import click
 
-from ..config import Config
+from .cli import KiwiCTX, pass_kiwi_ctx
 
 
 @click.command(
     "init",
-    short_help="Initializes a repo."
+    short_help="Initializes kiwi-scp"
 )
 @click.argument(
     "path",
     required=False,
     type=click.Path(resolve_path=True)
 )
-@click.pass_context
-def cmd(ctx, path):
-    """Initializes a repository."""
-    kiwi: Config = ctx.obj["cfg"]
-    click.echo("Hello init")
-    click.echo(kiwi.kiwi_yml)
+@pass_kiwi_ctx
+def cmd(ctx: KiwiCTX, path):
+    """Initialize or reconfigure a kiwi-scp instance"""
+
+    click.echo(f"Hello init, kiwi version {ctx.config.version}")
     pass

kiwi_scp/config.py

@@ -1,3 +1,4 @@
+import functools
 import re
 from ipaddress import IPv4Network
 from pathlib import Path
@@ -6,7 +7,7 @@ from typing import Optional, Dict, List, Any
 import yaml
 from pydantic import BaseModel, constr, root_validator, validator
 
-from ._constants import RE_SEMVER, RE_VARNAME, HEADER_KIWI_CONF_NAME
+from ._constants import RE_SEMVER, RE_VARNAME, HEADER_KIWI_CONF_NAME, KIWI_CONF_NAME
 
 
 # indent yaml lists
@@ -138,6 +139,20 @@ class Config(BaseModel):
         cidr="10.22.46.0/24",
     )
 
+    @classmethod
+    @functools.lru_cache(maxsize=5)
+    def from_instance(cls, instance: Path):
+        """parses an actual kiwi.yml from disk"""
+
+        try:
+            with open(instance.joinpath(KIWI_CONF_NAME)) as kc:
+                yml = yaml.safe_load(kc)
+                return cls.parse_obj(yml)
+
+        except FileNotFoundError:
+            # return the defaults if no kiwi.yml found
+            return cls()
+
     @property
     def kiwi_dict(self) -> Dict[str, Any]:
         """write this object as a dictionary of strings"""
@@ -201,7 +216,7 @@ class Config(BaseModel):
             try:
                 return [str(value)]
 
-            except Exception as e:
+            except Exception:
                 # undefined format
                 raise ValueError("Invalid Shells Format")
 
@@ -230,7 +245,7 @@ class Config(BaseModel):
                             # handle single project name
                             result.append({"name": str(entry)})
 
-                        except Exception as e:
+                        except Exception:
                             # undefined format
                             raise ValueError("Invalid Projects Format")
 
@@ -246,7 +261,7 @@ class Config(BaseModel):
                 # handle as a single project name
                 return [{"name": str(value)}]
 
-            except Exception as e:
+            except Exception:
                 # undefined format
                 raise ValueError("Invalid Projects Format")
 

kiwi_scp/scripts/kiwi_next.py

@@ -1,21 +1,14 @@
 import click
-import yaml
 
 from kiwi_scp.commands.cli import KiwiCLI
-from kiwi_scp.config import Config
 
 
 @click.command(cls=KiwiCLI)
-@click.pass_context
-def main(ctx):
-    """A complex command line interface."""
-
-    with open("./kiwi.yml") as kc:
-        yml = yaml.safe_load(kc)
-        ctx.ensure_object(dict)
-        ctx.obj["cfg"] = Config(**yml)
+def main():
+    """main entry point for command line interface"""
 
     click.echo("Hello main")
+    pass
 
 
 if __name__ == "__main__":

poetry.lock

@@ -10,7 +10,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 name = "attrs"
 version = "21.2.0"
 description = "Classes Without Boilerplate"
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 
@@ -73,7 +73,7 @@ python-versions = "*"
 
 [[package]]
 name = "filelock"
-version = "3.3.0"
+version = "3.3.1"
 description = "A platform independent file lock."
 category = "dev"
 optional = false
@@ -102,7 +102,7 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 
 [[package]]
 name = "importlib-resources"
-version = "5.2.2"
+version = "5.3.0"
 description = "Read resources from Python packages"
 category = "dev"
 optional = false
@@ -113,7 +113,7 @@ zipp = {version = ">=3.1.0", markers = "python_version < \"3.10\""}
 
 [package.extras]
 docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
-testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "pytest-black (>=0.3.7)", "pytest-mypy"]
+testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "pytest-black (>=0.3.7)", "pytest-mypy"]
 
 [[package]]
 name = "iniconfig"
@@ -283,7 +283,7 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6.1"
-content-hash = "eb1a3ab9af78ac7898062245858dbf9e9a27e82a6484f45f14b8db6c7fe812d6"
+content-hash = "872024f4d335f920d178ef6b631785f4f6908f8f9f87d970932bd54dee7fd297"
 
 [metadata.files]
 atomicwrites = [
@@ -315,16 +315,16 @@ distlib = [
     {file = "distlib-0.3.3.zip", hash = "sha256:d982d0751ff6eaaab5e2ec8e691d949ee80eddf01a62eaa96ddb11531fe16b05"},
 ]
 filelock = [
-    {file = "filelock-3.3.0-py3-none-any.whl", hash = "sha256:bbc6a0382fe8ec4744ecdf6683a2e07f65eb10ff1aff53fc02a202565446cde0"},
-    {file = "filelock-3.3.0.tar.gz", hash = "sha256:8c7eab13dc442dc249e95158bcc12dec724465919bdc9831fdbf0660f03d1785"},
+    {file = "filelock-3.3.1-py3-none-any.whl", hash = "sha256:2b5eb3589e7fdda14599e7eb1a50e09b4cc14f34ed98b8ba56d33bfaafcbef2f"},
+    {file = "filelock-3.3.1.tar.gz", hash = "sha256:34a9f35f95c441e7b38209775d6e0337f9a3759f3565f6c5798f19618527c76f"},
 ]
 importlib-metadata = [
     {file = "importlib_metadata-4.8.1-py3-none-any.whl", hash = "sha256:b618b6d2d5ffa2f16add5697cf57a46c76a56229b0ed1c438322e4e95645bd15"},
     {file = "importlib_metadata-4.8.1.tar.gz", hash = "sha256:f284b3e11256ad1e5d03ab86bb2ccd6f5339688ff17a4d797a0fe7df326f23b1"},
 ]
 importlib-resources = [
-    {file = "importlib_resources-5.2.2-py3-none-any.whl", hash = "sha256:2480d8e07d1890056cb53c96e3de44fead9c62f2ba949b0f2e4c4345f4afa977"},
-    {file = "importlib_resources-5.2.2.tar.gz", hash = "sha256:a65882a4d0fe5fbf702273456ba2ce74fe44892c25e42e057aca526b702a6d4b"},
+    {file = "importlib_resources-5.3.0-py3-none-any.whl", hash = "sha256:7a65eb0d8ee98eedab76e6deb51195c67f8e575959f6356a6e15fd7e1148f2a3"},
+    {file = "importlib_resources-5.3.0.tar.gz", hash = "sha256:f2e58e721b505a79abe67f5868d99f8886aec8594c962c7490d0c22925f518da"},
 ]
 iniconfig = [
     {file = "iniconfig-1.1.1-py2.py3-none-any.whl", hash = "sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3"},

pyproject.toml

@@ -6,14 +6,15 @@ authors = ["ldericher <40151420+ldericher@users.noreply.github.com>"]
 
 [tool.poetry.dependencies]
 python = "^3.6.1"
-PyYAML = "^5.4.1"
-pydantic = "^1.8.2"
+attrs = "^21.2.0"
 click = "^8.0.3"
+pydantic = "^1.8.2"
+PyYAML = "^5.4.1"
 
 [tool.poetry.dev-dependencies]
-virtualenv = "^20.8.1"
 pytest = "^6.2.5"
 toml = "^0.10.2"
+virtualenv = "^20.8.1"
 
 [tool.poetry.scripts]
 kiwi = "kiwi_scp.scripts.kiwi:main"