Implement composing tweets using an editor

fixes #90

toot/commands.py

@@ -1,11 +1,13 @@
 # -*- coding: utf-8 -*-
 
+import sys
+
 from toot import api, config
 from toot.auth import login_interactive, login_browser_interactive, create_app_interactive
 from toot.exceptions import ConsoleError, NotFoundError
 from toot.output import (print_out, print_instance, print_account,
                          print_search_results, print_timeline, print_notifications)
-from toot.utils import assert_domain_exists, multiline_input, EOF_KEY
+from toot.utils import assert_domain_exists, editor_input, multiline_input, EOF_KEY
 
 
 def get_timeline_generator(app, user, args):
@@ -76,9 +78,17 @@ def curses(app, user, args):
 
 
 def post(app, user, args):
+    # TODO: this might be achievable, explore options
+    if args.editor and not sys.stdin.isatty():
+        raise ConsoleError("Cannot run editor if not in tty.")
+
     if args.media and len(args.media) > 4:
         raise ConsoleError("Cannot attach more than 4 files.")
 
+    # Read any text that might be piped to stdin
+    if not args.text and not sys.stdin.isatty():
+        args.text = sys.stdin.read().rstrip()
+
     if args.media:
         media = [_do_upload(app, user, file) for file in args.media]
         media_ids = [m["id"] for m in media]
@@ -89,7 +99,9 @@ def post(app, user, args):
     if media and not args.text:
         args.text = "\n".join(m['text_url'] for m in media)
 
-    if not args.text:
+    if args.editor:
+        args.text = editor_input(args.editor, args.text)
+    elif not args.text:
         print_out("Write or paste your toot. Press <yellow>{}</yellow> to post it.".format(EOF_KEY))
         args.text = multiline_input()
 

toot/console.py

@@ -1,8 +1,9 @@
 # -*- coding: utf-8 -*-
 
-import os
-import sys
 import logging
+import os
+import shutil
+import sys
 
 from argparse import ArgumentParser, FileType, ArgumentTypeError
 from collections import namedtuple
@@ -39,6 +40,21 @@ def timeline_count(value):
     return n
 
 
+def editor(value):
+    if not value:
+        raise ArgumentTypeError(
+            "Editor not specified in --editor option and $EDITOR environment "
+            "variable not set."
+        )
+
+    # Check editor executable exists
+    exe = shutil.which(value)
+    if not exe:
+        raise ArgumentTypeError(f"Editor `{value}` not found")
+
+    return exe
+
+
 Command = namedtuple("Command", ["name", "description", "require_auth", "arguments"])
 
 
@@ -298,6 +314,13 @@ POST_COMMANDS = [
                 "type": language,
                 "help": "ISO 639-2 language code of the toot, to skip automatic detection",
             }),
+            (["-e", "--editor"], {
+                "type": editor,
+                "nargs": "?",
+                "const": os.getenv("EDITOR", ""),  # option given without value
+                "help": "Specify an editor to compose your toot, "
+                        "defaults to editor defined in $EDITOR env variable.",
+            }),
         ],
         require_auth=True,
     ),
@@ -500,12 +523,6 @@ def main():
         filename = os.getenv("TOOT_LOG_FILE")
         logging.basicConfig(level=logging.DEBUG, filename=filename)
 
-    # If something is piped in, append it to commandline arguments
-    if not sys.stdin.isatty():
-        stdin = sys.stdin.read()
-        if stdin:
-            sys.argv.append(stdin)
-
     command_name = sys.argv[1] if len(sys.argv) > 1 else None
     args = sys.argv[2:]
 
@@ -519,5 +536,5 @@ def main():
     except (ConsoleError, ApiError) as e:
         print_err(str(e))
         sys.exit(1)
-    except KeyboardInterrupt as e:
+    except KeyboardInterrupt:
         pass

toot/utils.py

@@ -3,6 +3,8 @@
 import os
 import re
 import socket
+import subprocess
+import tempfile
 import unicodedata
 import warnings
 
@@ -88,3 +90,27 @@ def multiline_input():
             break
 
     return "\n".join(lines).strip()
+
+
+EDITOR_INPUT_INSTRUCTIONS = """
+# Please enter your toot. Lines starting with '#' will be ignored, and an empty
+# message aborts the post.
+"""
+
+
+def editor_input(editor, initial_text):
+    """Lets user input text using an editor."""
+    initial_text = (initial_text or "") + EDITOR_INPUT_INSTRUCTIONS
+
+    with tempfile.NamedTemporaryFile() as f:
+        f.write(initial_text.encode())
+        f.flush()
+
+        subprocess.run([editor, f.name])
+
+        f.seek(0)
+        text = f.read().decode()
+
+    lines = text.strip().splitlines()
+    lines = (l for l in lines if not l.startswith("#"))
+    return "\n".join(lines)