print real time

README.md

@@ -6,6 +6,8 @@ Yes, I know Gotify doesn't have "goat" in its name but it sounds like it.
 
 ## Configuration
 
+Configuration lives in a TOML file which should have (at a minimum) the following:
+
 ```toml
 server = "https://gotify.example.com"
 app_token = "app_token_from_gotify"
@@ -15,7 +17,7 @@ app_token = "app_token_from_gotify"
 ## Usage
 
 ```
-goat_monitor --config ./config.toml --retries -1 -- <COMMAND TO MONITOR>
+goat_monitor --config ./config.toml --retries 3 -- <COMMAND TO MONITOR>
 ```
 
 The command can be any shell command including arbitrarily many options / arguments.

goat_monitor/goat_monitor.py

@@ -17,7 +17,8 @@ from goat_monitor._version import __version__  # type: ignore
 @click.argument("command", nargs=-1, required=False, type=str)
 @click.option(
     "--config",
-    default="~/.config/goat_monitor.toml",
+    # default="~/.config/goat_monitor.toml",
+    required=True,
     type=click.Path(path_type=Path),
     help="Use a .toml configuration file",
 )
@@ -33,7 +34,13 @@ from goat_monitor._version import __version__  # type: ignore
     default=False,
     help="Print version and exit",
 )
-def wrap(command: List[str], config: Path, retries: int, version):
+@click.option(
+    "--dry-run",
+    is_flag=True,
+    default=False,
+    help="Run command without sending any notifications",
+)
+def wrap(command: List[str], config: Path, retries: int, version: bool, dry_run: bool):
     """Wrap an arbitrary command with gotify notifications"""
 
     if version:
@@ -45,35 +52,42 @@ def wrap(command: List[str], config: Path, retries: int, version):
         settings = toml.load(f)
 
     # gotify configuration
-    url = settings["server"]
-    app_token = settings["app_token"]
-    with gotify.Gotify(base_url=url, app_token=app_token) as gotify_connection:
-        # this is just to test configuration.
-        # I don't know how long a gotify connection will stay up so rather than thinking about it
-        # I'm just creating a new one whenever I need to send a message
-        pass
+    if not dry_run:
+        url = settings["server"]
+        app_token = settings["app_token"]
+        with gotify.Gotify(base_url=url, app_token=app_token) as gotify_connection:
+            # this is just to test configuration.
+            # I don't know how long a gotify connection will stay up so rather than thinking about it
+            # I'm just creating a new one whenever I need to send a message
+            pass
 
     if retries == -1:
         retries = np.inf
     if retries < 0:
         raise ValueError("Invalid number of retries specified")
 
-    for attempt in range(retries + 1):
+    attempt = 0
+    while attempt <= retries:
         # run the command
-        result = subprocess.run(
+        with subprocess.Popen(
             " ".join(command),
             shell=True,
             stderr=subprocess.STDOUT,
             stdout=subprocess.PIPE,
-            encoding="utf-8",
-        )
+        ) as proc:
+            stdout = ""
+            while True:
+                c = proc.stdout.read(1)
+                if c == b"":
+                    break
+                s = c.decode("utf-8")
+                stdout += s
+                print(s, end="", flush=True)
+            return_code = proc.wait()
 
-        # TODO: print lines real time as the subprocess runs
-        print(result.stdout, end="")
-
-        if result.returncode:
+        if return_code:
             # failed
-            title = f"Command failed with exit code {result.returncode}"
+            title = f"Command failed with exit code {return_code}"
             if attempt < retries:
                 title += f" - Retrying (attempt {attempt+1}/{retries})"
             else:
@@ -83,7 +97,7 @@ def wrap(command: List[str], config: Path, retries: int, version):
             title = "Command succeeded"
 
         MAX_LINES = 20
-        lines = result.stdout.splitlines()
+        lines = stdout.splitlines()
         if len(lines) > MAX_LINES:
             lines = lines[-MAX_LINES:]
         message = (
@@ -93,14 +107,17 @@ def wrap(command: List[str], config: Path, retries: int, version):
             + "\n".join(lines)
         )
 
-        with gotify.Gotify(base_url=url, app_token=app_token) as gotify_connection:
-            gotify_connection.create_message(message=message, title=title)
+        if not dry_run:
+            with gotify.Gotify(base_url=url, app_token=app_token) as gotify_connection:
+                gotify_connection.create_message(message=message, title=title)
 
-        if not result.returncode:
+        if not return_code:
             # only retry on failure
             break
 
-    sys.exit(result.returncode)
+        attempt += 1
+
+    sys.exit(return_code)
 
 
 # %% main