add feature for automatic init of a TZK repository

.gitignore

@@ -1 +1,2 @@
 __pycache__/
+.vscode/

config.py

@@ -1,27 +1,56 @@
+import datetime
 import importlib
 import os
 from pathlib import Path
 import sys
+from typing import Any
+
+from util import fail
 
 
 class ConfigurationManager:
     def __init__(self):
-        config_path = Path.cwd()
+        self.config_path = Path.cwd()
 
-        for child in sorted(config_path.iterdir()):
+        for child in sorted(self.config_path.iterdir()):
             if child.is_file() and child.name.endswith('.py'):
                 mod_name = child.name.rsplit('.', 1)[0]
                 if mod_name == 'tzk_config':
-                    sys.path.insert(0, str(config_path))
+                    sys.path.insert(0, str(self.config_path))
                     self.conf_mod = importlib.import_module(mod_name)
                     del sys.path[0]
                     break
         else:
-            print(
+            fail(
                 f"Your TZK config file could not be found. "
                 f"Please ensure there is a file called tzk_config.py "
-                f"in the current directory.", file=sys.stderr)
-            sys.exit(1)
+                f"in the current directory.")
 
     def __getattr__(self, attr):
         return getattr(self.conf_mod, attr, None)
+
+    def write_attr(self, attr: str, value: str) -> bool:
+        """
+        Try to add a simple attribute = string value config parameter to the
+        config file, if it doesn't already exist. More complicated data types
+        are not supported.
+
+        Return:
+            False if the attribute already has a value.
+            True if successful.
+
+        Raises:
+            File access errors if the config file is inaccessible.
+        """
+
+        if hasattr(self.conf_mod, attr):
+            return False
+        else:
+            setattr(self.conf_mod, attr, value)
+            with open(self.config_path / "tzk_config.py", "a") as f:
+                now = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+                f.write(f"\n# Added automatically by tzk at {now}\n")
+                f.write(f'{attr} = "{value}"\n')
+            return True
+
+cm = ConfigurationManager()

git.py

@@ -1,8 +1,8 @@
 import subprocess
 from typing import Sequence
 
-def exec(*args: Sequence[str]):
-    return subprocess.call(["git", *args])
+def exec(*args: str):
+    return subprocess.check_call(["git", *args])
 
-def read(*args: Sequence[str]):
-    return subprocess.check_output(["git", *args], text=True).strip()
+def read(*args: str):
+    return subprocess.check_output(["git", *args], text=True).strip()

tw.py

@@ -1,12 +1,162 @@
+from contextlib import contextmanager
+import functools
+import json
+import os
+from pathlib import Path
 import subprocess
-from typing import Sequence
+from textwrap import dedent
+from typing import Optional, Sequence
+
+from config import cm
+import git
 
 
-def exec(args: Sequence[Sequence[str]]) -> None:
-    bin_dir = subprocess.check_output(("npm", "bin"), text=True).strip()
-    call_args = [bin_dir + "/tiddlywiki"]
+@functools.lru_cache(1)
+def _npm_bin() -> str:
+    return subprocess.check_output(("npm", "bin"), text=True).strip()
+
+@contextmanager
+def _pushd(directory: str):
+    """
+    Change directory into the directory /directory/ until the end of the with-block,
+    then return to previous directory.
+    """
+    old_directory = os.getcwd()
+    try:
+        os.chdir(directory)
+        yield
+    finally:
+        os.chdir(old_directory)
+
+def _tw_path() -> str:
+    return _npm_bin() + "/tiddlywiki"
+
+@functools.lru_cache(1)
+def _whoami() -> str:
+    try:
+        return subprocess.check_output(("whoami",), text=True).strip()
+    except subprocess.CalledProcessError:
+        return "user"
+
+
+def exec(args: Sequence[Sequence[str]]) -> int:
+    call_args = [_tw_path()]
     for tw_arg in args:
         call_args.append(f"--{tw_arg[0]}")
         for inner_arg in tw_arg[1:]:
             call_args.append(inner_arg)
-    return subprocess.call(call_args)
+    return subprocess.call(call_args)
+
+
+def _init_npm(wiki_name: str, tw_version_spec: str, author: str) -> None:
+    """
+    Create a package.json file for this repository, requiring TiddlyWiki
+    at the specified version, and install the npm dependencies.
+    """
+    print("tzk: Creating package.json...")
+    PACKAGE_JSON = dedent("""
+    {
+        "name": "%(wiki_name)s",
+        "version": "1.0.0",
+        "description": "My nice notes",
+        "dependencies": {
+            "tiddlywiki": "%(tw_version_spec)s"
+        },
+        "author": "%(author)s",
+        "license": "See copyright notice in wiki"
+    }
+    """).strip() % ({'tw_version_spec': tw_version_spec, 'author': author,
+                     'wiki_name': wiki_name})
+    with open("package.json", "w") as f:
+        f.write(PACKAGE_JSON)
+
+    print("tzk: Installing npm packages from package.json...")
+    subprocess.check_call(("npm", "install"))
+
+
+def _init_tw(wiki_name: str) -> None:
+    """
+    Create a new TiddlyWiki in the subfolder named 'wiki_name'
+    using 'tiddlywiki --init'.
+    """
+    print("tzk: Creating new TiddlyWiki...")
+    try:
+        os.mkdir(wiki_name)
+    except FileExistsError:
+        pass
+    with _pushd(wiki_name):
+        subprocess.check_call((_tw_path(), "--init"))
+
+
+def _save_wikifolder_to_config(wiki_name: str) -> bool:
+    """
+    Set the wiki_folder config option to the wiki_name we initialized with,
+    if it's not already set in the config.
+
+    Return True if the option ended set to wiki_name, False otherwise.
+    """
+    print("tzk: Writing new wiki folder to config file...")
+    if not cm.write_attr("wiki_folder", wiki_name):
+        if cm.wiki_folder == wiki_name:
+            print("tzk: (Looks like it was already there.)")
+        else:
+            print(f"tzk: WARNING: The wiki_folder option in your config appears "
+                  f"to be set to '{cm.wiki_folder}', rather than the wiki folder "
+                  f"you're initializing, {wiki_name}. Please check your config file "
+                  "and update this option if necessary.")
+            return False
+    return True
+
+
+def _add_filesystem_plugins(wiki_name: str) -> None:
+    print("tzk: Adding filesystem plugins to tiddlywiki.info...")
+    info_path = Path.cwd() / wiki_name / "tiddlywiki.info"
+    with info_path.open("r") as f:
+        info_data = json.load(f)
+    info_data['plugins'] = ["tiddlywiki/filesystem", "tiddlywiki/tiddlyweb"]
+    with info_path.open("w") as f:
+        json.dump(info_data, f)
+
+
+def _init_gitignore() -> None:
+    print("tzk: Creating gitignore...")
+    GITIGNORE = dedent("""
+    __pycache__/
+    node_modules/
+    .peru/
+    output/
+
+    \$__StoryList.tid
+    """).strip()
+    with open(".gitignore", "w") as f:
+        f.write(GITIGNORE)
+
+
+def _initial_commit() -> None:
+    print("tzk: Initializing new Git repository for wiki...")
+    git.exec("init")
+
+    print("tzk: Committing changes to repository...")
+    git.exec("add", "-A")
+    git.exec("commit", "-m", "Initial commit")
+
+
+def install(wiki_name: str, tw_version_spec: str, author: Optional[str]):
+    # assert: caller has checked npm and git are installed
+    warnings = False
+
+    if author is None:
+        author = _whoami()
+
+    _init_npm(wiki_name, tw_version_spec, author)
+    _init_tw(wiki_name)
+    warnings |= not _save_wikifolder_to_config(wiki_name)
+    _add_filesystem_plugins(wiki_name)
+    _init_gitignore()
+    _initial_commit()
+
+    if warnings:
+        print("tzk: Initialization completed with warnings. Read the output and "
+              "make any changes required, then run 'tzk listen' to start the server.")
+    else:
+        print("tzk: Initialized successfully. Run 'tzk listen' to start the server.")

tzk.py

@@ -1,20 +1,26 @@
 from abc import ABC, abstractmethod, abstractclassmethod
 import argparse
 import os
+import shutil
 import sys
+from typing import Optional
 
-import config
+from config import cm
 import git
 import tw
+from util import fail
 
 
 class CliCommand(ABC):
+    cmd = None   # type: str
+    help = None  # type: str
+
     @abstractclassmethod
-    def setup_arguments(self, parser: argparse.ArgumentParser) -> None:
+    def setup_arguments(cls, parser: argparse.ArgumentParser) -> None:
         raise NotImplementedError
 
     @abstractmethod
-    def execute(self, parser: argparse.ArgumentParser) -> None:
+    def execute(self, parser: argparse.Namespace) -> None:
         raise NotImplementedError
 
 
@@ -23,7 +29,7 @@ class CommitCommand(CliCommand):
     help = "Commit all changes to the wiki repository."
 
     @classmethod
-    def setup_arguments(self, parser: argparse.ArgumentParser) -> None:
+    def setup_arguments(cls, parser: argparse.ArgumentParser) -> None:
         parser.add_argument(
             "-m", "--message",
             metavar="MSG",
@@ -46,11 +52,9 @@ class CommitCommand(CliCommand):
         if cm.commit_require_branch:
             current_branch = git.read("rev-parse", "--abbrev-ref", "HEAD")
             if current_branch != cm.commit_require_branch:
-                print(f"You are on the '{current_branch}' branch, "
-                      f"but your TZK configuration requires you to be on the "
-                      f"'{cm.commit_require_branch}' branch to commit.",
-                      file=sys.stderr)
-                sys.exit(1)
+                fail(f"You are on the '{current_branch}' branch, "
+                     f"but your TZK configuration requires you to be on the "
+                     f"'{cm.commit_require_branch}' branch to commit.")
 
         git.exec("add", "-A")
         git.exec("commit", "-m", args.message)
@@ -63,7 +67,7 @@ class ListenCommand(CliCommand):
     help = "Start a TiddlyWiki server in the current directory."
 
     @classmethod
-    def setup_arguments(self, parser: argparse.ArgumentParser) -> None:
+    def setup_arguments(cls, parser: argparse.ArgumentParser) -> None:
         parser.add_argument(
             "-p", "--port",
             metavar="PORT",
@@ -84,27 +88,85 @@ class ListenCommand(CliCommand):
         )
     
     def execute(self, args: argparse.Namespace) -> None:
-        tw.exec(
-            [
-                ("listen",
-                 f"port={args.port}",
-                 f"username={args.username}",
-                 f"password={args.password}")
-            ]
+        try:
+            tw.exec(
+                [
+                    ("listen",
+                    f"port={args.port}",
+                    f"username={args.username}",
+                    f"password={args.password}")
+                ]
+            )
+        except KeyboardInterrupt:
+            # We'll terminate anyway now that we're at the end of execute() --
+            # no need to display the traceback to the user.
+            pass
+
+
+class InitCommand(CliCommand):
+    cmd = "init"
+    help = "Set up a new TZK directory."
+
+    @classmethod
+    def setup_arguments(cls, parser: argparse.ArgumentParser) -> None:
+        parser.add_argument(
+            "-n", "--wiki-name",
+            metavar="NAME",
+            help="The wiki will be installed in a subfolder of the current directory, called NAME.",
+            default="wiki",
+        )
+        parser.add_argument(
+            "-v", "--tiddlywiki-version-spec",
+            metavar="SPEC",
+            help="NPM version spec for the version of TiddlyWiki to start your package.json at.",
+            default="^5.1.23",
+        )
+        parser.add_argument(
+            "-a", "--author",
+            metavar="AUTHOR_NAME",
+            help="The author to be credited in the package.json, if not your current username.",
+            default=None,
         )
 
+    def _precheck(self):
+        if shutil.which("npm") is None:
+            fail("TZK requires NPM. Please install NPM and make it available on your PATH.\n"
+                 "https://docs.npmjs.com/downloading-and-installing-node-js-and-npm")
+
+        if shutil.which("git") is None:
+            fail("TZK requires Git. Please install Git and make it available on your PATH.\n"
+                 "https://git-scm.com/book/en/v2/Getting-Started-Installing-Git")
+
+        if os.path.exists("package.json"):
+            fail("A 'package.json' file already exists in the current directory. "
+                 "Perhaps you've already initialized a TZK repository here?")
+
+    def execute(self, args: argparse.Namespace) -> None:
+        self._precheck()
+        tw.install(args.wiki_name, args.tiddlywiki_version_spec, args.author)
 
-cm = config.ConfigurationManager()
 
-os.chdir("zk-wiki")
-# TODO: confirm we're in the right directory
 
 parser = argparse.ArgumentParser()
 subparsers = parser.add_subparsers()
 for command in CliCommand.__subclasses__():
     subparser = subparsers.add_parser(command.cmd, help=command.help)
     subparser.set_defaults(_cls=command)
-    command.setup_arguments(subparser)
+    command.setup_arguments(subparser)  # type: ignore
 
 args = parser.parse_args()
+
+# For all operations except 'init', we start in the wiki folder.
+if not args._cls.cmd == "init":
+    if not cm.wiki_folder:
+        fail("No 'wiki_folder' option found in config. Set this option to the name "
+            "of the wiki subfolder within the current directory.")
+
+    try:
+        os.chdir(cm.wiki_folder)
+    except FileNotFoundError:
+        fail(f"Tried to change directory into the wiki_folder '{cm.wiki_folder}' "
+            f"specified in your config file, but that directory does not exist.")
+    # TODO: confirm we're in the right directory
+
 args._cls().execute(args)

util.py

@@ -0,0 +1,7 @@
+import sys
+from typing import NoReturn
+
+def fail(msg: str, exit_code: int = 1) -> NoReturn:
+    print(msg, file=sys.stderr)
+    sys.exit(exit_code)
+