From 855bb922fc4c319c76eb4d4c90b46ab94b7f7b62 Mon Sep 17 00:00:00 2001
From: Jimmy Bradshaw <jbradshaw@austin.utexas.edu>
Date: Tue, 7 Jan 2020 00:10:46 -0600
Subject: [PATCH] Add CLI for running Shattered apps

---
 examples/chat/Dockerfile         |  1 +
 examples/chat/chat.py            |  4 ---
 examples/chat/docker-compose.yml |  4 +--
 pyproject.toml                   |  5 +++-
 src/shattered/__init__.py        |  2 +-
 src/shattered/cli.py             | 47 ++++++++++++++++++++++++++++++++
 src/shattered/shattered.py       | 19 +++++++++----
 7 files changed, 69 insertions(+), 13 deletions(-)
 create mode 100644 src/shattered/cli.py

diff --git a/examples/chat/Dockerfile b/examples/chat/Dockerfile
index d331e8d..c4a2f05 100644
--- a/examples/chat/Dockerfile
+++ b/examples/chat/Dockerfile
@@ -2,6 +2,7 @@ FROM python:3
 
 ENV FLASK_APP=chat.py
 ENV FLASK_ENV=development
+ENV SHATTERED_APP=chat.py
 
 COPY requirements.txt /src/requirements.txt
 
diff --git a/examples/chat/chat.py b/examples/chat/chat.py
index e51357d..b5f8827 100644
--- a/examples/chat/chat.py
+++ b/examples/chat/chat.py
@@ -21,7 +21,3 @@ def echo(headers, body, conn):
     data = dict(parse_qsl(body))
     email = data["email"]
     conn.send(body=f'<li>{email}: {data["message"]}</li>', destination="/topic/chat")
-
-
-if __name__ == "__main__":
-    shattered_app.run()
diff --git a/examples/chat/docker-compose.yml b/examples/chat/docker-compose.yml
index 92256b2..ffd35b7 100644
--- a/examples/chat/docker-compose.yml
+++ b/examples/chat/docker-compose.yml
@@ -15,8 +15,8 @@ services:
         "300",
         "rabbitmq:61613",
         "--",
-        "python",
-        "chat.py",
+        "shattered",
+        "run",
       ]
   chat:
     build: .
diff --git a/pyproject.toml b/pyproject.toml
index 9479744..6b705a5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,12 +1,15 @@
 [tool.poetry]
 name = "shattered"
-version = "0.2.0"
+version = "0.3.0"
 description = "STOMP meets bottle.py"
 authors = ["Jimmy Bradshaw <james.g.bradshaw@gmail.com>"]
 repository = "https://github.com/bradshjg/shattered"
 license = "MIT"
 readme = "README-PYPI.md"
 
+[tool.poetry.scripts]
+shattered = "shattered.cli:main"
+
 [tool.poetry.dependencies]
 python = "^3.6"
 "stomp.py" = "^5.0.0"
diff --git a/src/shattered/__init__.py b/src/shattered/__init__.py
index c3d2549..831105d 100644
--- a/src/shattered/__init__.py
+++ b/src/shattered/__init__.py
@@ -1,3 +1,3 @@
-__version__ = "0.2.0"
+__version__ = "0.3.0"
 
 from shattered.shattered import Shattered
diff --git a/src/shattered/cli.py b/src/shattered/cli.py
new file mode 100644
index 0000000..2b6d57e
--- /dev/null
+++ b/src/shattered/cli.py
@@ -0,0 +1,47 @@
+import argparse
+import os
+import sys
+
+from .shattered import Shattered
+
+
+def load_app(args):
+    sys.path.insert(0, os.getcwd())
+    module_file = args.app or os.getenv("SHATTERED_APP", "app.py")
+    module_name = os.path.splitext(module_file)[0]
+    __import__(module_name)
+    module = sys.modules[module_name]
+    matches = [v for v in module.__dict__.values() if isinstance(v, Shattered)]
+    if len(matches) == 1:
+        return matches[0]
+    else:
+        raise EnvironmentError("Detected multiple Shattered applications.")
+
+
+def run_app(args):
+    app = load_app(args)
+    app.run()
+
+
+def print_config(args):
+    app = load_app(args)
+    for k, v in app.config.items():
+        print(f"{k}: {v}")
+
+
+def parse_arguments():
+    parser = argparse.ArgumentParser(prog="shattered")
+    parser.add_argument("-a", "--app", help="shattered app")
+    subparsers = parser.add_subparsers(
+        title="subcommands", description="valid subcommands", help="additional help"
+    )
+    parser_run = subparsers.add_parser("run", help="run shattered app")
+    parser_run.set_defaults(func=run_app)
+    parser_config = subparsers.add_parser("config", help="show shattered app config")
+    parser_config.set_defaults(func=print_config)
+    return parser.parse_args()
+
+
+def main():
+    args = parse_arguments()
+    args.func(args)
diff --git a/src/shattered/shattered.py b/src/shattered/shattered.py
index f9fbfbd..c5884b3 100644
--- a/src/shattered/shattered.py
+++ b/src/shattered/shattered.py
@@ -27,16 +27,25 @@ def on_message(self, headers, body):
 class Shattered:
     def __init__(self, **config):
         self.config = config
-        self.host = self.config.get("host", "localhost")
-        self.port = self.config.get("port", 61613)
-        self.username = self.config.get("username", "guest")
-        self.password = self.config.get("password", "guest")
-        self.vhost = self.config.get("vhost", "/")
+        self._set_config_defaults()
+
+        self.host = self.config["host"]
+        self.port = self.config["port"]
+        self.username = self.config["username"]
+        self.password = self.config["password"]
+        self.vhost = self.config["vhost"]
 
         self.subscriptions = {}
         self.conn = None
         self.listener = ShatteredListener(self)
 
+    def _set_config_defaults(self):
+        self.config.setdefault("host", "localhost")
+        self.config.setdefault("port", 61613)
+        self.config.setdefault("username", "guest")
+        self.config.setdefault("password", "guest")
+        self.config.setdefault("vhost", "/")
+
     def add_subscription(self, destination, callback):
         if destination not in self.subscriptions:
             self.subscriptions[destination] = []