First draft.

examples/debug.py

@@ -0,0 +1,15 @@
+#!/usr/bin/env python3.6
+# coding=utf-8
+import json
+
+from qutescript import qutescript
+
+
+@qutescript
+def dump_to_log(request):
+    with open('qutescript.debug.log', 'a') as logfile:
+        line = json.dumps(request.dump())
+        logfile.writelines([line])
+
+if __name__ == '__main__':
+    dump_to_log()

src/qutescript/__init__.py

@@ -1 +1,10 @@
 __version__ = "0.1.0"
+
+from .decorators import qutescript
+from .request import Request, build_request
+
+__all__ = [
+    'build_request',
+    'qutescript',
+    'Request',
+]

src/qutescript/decorators.py

@@ -0,0 +1,33 @@
+# coding=utf-8
+
+import sys
+
+import os
+
+from .request import build_request
+
+log_file_path = './qutescript.log'
+
+
+def write_log(message, file_path=None):
+    file_path = file_path or log_file_path
+    file_path = os.path.abspath(os.path.expanduser(file_path))
+    with open(file_path, 'a') as logfile:
+        logfile.writelines([message])
+
+
+def qutescript(func):
+    def wrapper():
+        request = build_request()
+        command = func(request)
+        if not command:
+            return
+        if not request.fifo:
+            write_log('ERROR: userscript returned command: {}, '
+                      'but QUTE_FIFO was not found in passed environment.\n'
+                      'Try: :spawn --userscript /path/to/script ?')
+            sys.exit(1)
+        with open(request.fifo, 'w') as fifo:
+            fifo.write('{}\n'.format(command))
+
+    return wrapper

src/qutescript/request.py

@@ -0,0 +1,54 @@
+# coding=utf-8
+
+
+class Request(object):
+    def __init__(self):
+        self.mode = None
+        self.user_agent = None
+        self.fifo = None
+        self.html = None
+        self.text = None
+        self.config_dir = None
+        self.data_dir = None
+        self.download_dir = None
+        self.commandline_text = None
+        self.url = None
+        self.title = None
+        self.selected_text = None
+        self.selected_html = None
+
+    def dump(self):
+        return {
+            'mode': self.mode,
+            'user_agent': self.user_agent,
+            'fifo': self.fifo,
+            'html': self.html,
+            'text': self.text,
+            'config_dir': self.config_dir,
+            'data_dir': self.data_dir,
+            'download_dir': self.download_dir,
+            'commandline_text': self.commandline_text,
+            'url': self.url,
+            'title': self.title,
+            'selected_text': self.selected_text,
+            'selected_html': self.selected_html,
+        }
+
+
+def build_request():
+    import os
+    request = Request()
+    request.mode = os.getenv('QUTE_MODE')
+    request.user_agent = os.getenv('QUTE_USER_AGENT')
+    request.fifo = os.getenv('QUTE_FIFO')
+    request.html = os.getenv('QUTE_HTML')
+    request.text = os.getenv('QUTE_TEXT')
+    request.config_dir = os.getenv('QUTE_CONFIG_DIR')
+    request.data_dir = os.getenv('QUTE_DATA_DIR')
+    request.download_dir = os.getenv('QUTE_DOWNLOAD_DIR')
+    request.commandline_text = os.getenv('QUTE_COMMANDLINE_TEXT')
+    request.url = os.getenv('QUTE_URL')
+    request.title = os.getenv('QUTE_TITLE')
+    request.selected_text = os.getenv('QUTE_SELECTED_TEXT')
+    request.selected_html = os.getenv('QUTE_SELECTED_HTML')
+    return request