configfile: Split configfile code into three separate classes

Separate out the low-level parsing code to a new ConfigFileReader()
class.

Separate out the auto-save handling code to a new ConfigAutoSave()
class.

This simplifies the main PrinterConfig() class.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/configfile.py

@@ -1,12 +1,17 @@
 # Code for reading and writing the Klipper config file
 #
-# Copyright (C) 2016-2021  Kevin O'Connor <kevin@koconnor.net>
+# Copyright (C) 2016-2024  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import sys, os, glob, re, time, logging, configparser, io
 
 error = configparser.Error
 
+
+######################################################################
+# Config section parsing helper
+######################################################################
+
 class sentinel:
     pass
 
@@ -134,30 +139,13 @@ class ConfigWrapper:
         pconfig = self.printer.lookup_object("configfile")
         pconfig.deprecate(self.section, option, value, msg)
 
-AUTOSAVE_HEADER = """
-#*# <---------------------- SAVE_CONFIG ---------------------->
-#*# DO NOT EDIT THIS BLOCK OR BELOW. The contents are auto-generated.
-#*#
-"""
 
-class PrinterConfig:
+######################################################################
-    def __init__(self, printer):
+# Config file parsing (with include file support)
-        self.printer = printer
+######################################################################
-        self.autosave = None
+
-        self.deprecated = {}
+class ConfigFileReader:
-        self.runtime_warnings = []
+    def read_config_file(self, filename):
-        self.deprecate_warnings = []
-        self.status_raw_config = {}
-        self.status_save_pending = {}
-        self.status_settings = {}
-        self.status_warnings = []
-        self.save_config_pending = False
-        gcode = self.printer.lookup_object('gcode')
-        gcode.register_command("SAVE_CONFIG", self.cmd_SAVE_CONFIG,
-                               desc=self.cmd_SAVE_CONFIG_help)
-    def get_printer(self):
-        return self.printer
-    def _read_config_file(self, filename):
         try:
             f = open(filename, 'r')
             data = f.read()
@@ -167,53 +155,6 @@ class PrinterConfig:
             logging.exception(msg)
             raise error(msg)
         return data.replace('\r\n', '\n')
-    def _find_autosave_data(self, data):
-        regular_data = data
-        autosave_data = ""
-        pos = data.find(AUTOSAVE_HEADER)
-        if pos >= 0:
-            regular_data = data[:pos]
-            autosave_data = data[pos + len(AUTOSAVE_HEADER):].strip()
-        # Check for errors and strip line prefixes
-        if "\n#*# " in regular_data:
-            logging.warning("Can't read autosave from config file"
-                            " - autosave state corrupted")
-            return data, ""
-        out = [""]
-        for line in autosave_data.split('\n'):
-            if ((not line.startswith("#*#")
-                 or (len(line) >= 4 and not line.startswith("#*# ")))
-                and autosave_data):
-                logging.warning("Can't read autosave from config file"
-                                " - modifications after header")
-                return data, ""
-            out.append(line[4:])
-        out.append("")
-        return regular_data, "\n".join(out)
-    comment_r = re.compile('[#;].*$')
-    value_r = re.compile('[^A-Za-z0-9_].*$')
-    def _strip_duplicates(self, data, config):
-        # Comment out fields in 'data' that are defined in 'config'
-        lines = data.split('\n')
-        section = None
-        is_dup_field = False
-        for lineno, line in enumerate(lines):
-            pruned_line = self.comment_r.sub('', line).rstrip()
-            if not pruned_line:
-                continue
-            if pruned_line[0].isspace():
-                if is_dup_field:
-                    lines[lineno] = '#' + lines[lineno]
-                continue
-            is_dup_field = False
-            if pruned_line[0] == '[':
-                section = pruned_line[1:-1].strip()
-                continue
-            field = self.value_r.sub('', pruned_line)
-            if config.fileconfig.has_option(section, field):
-                is_dup_field = True
-                lines[lineno] = '#' + lines[lineno]
-        return "\n".join(lines)
     def _parse_config_buffer(self, buffer, filename, fileconfig):
         if not buffer:
             return
@@ -235,7 +176,7 @@ class PrinterConfig:
             raise error("Include file '%s' does not exist" % (include_glob,))
         include_filenames.sort()
         for include_filename in include_filenames:
-            include_data = self._read_config_file(include_filename)
+            include_data = self.read_config_file(include_filename)
             self._parse_config(include_data, include_filename, fileconfig,
                                visited)
         return include_filenames
@@ -265,30 +206,209 @@ class PrinterConfig:
                 buffer.append(line)
         self._parse_config_buffer(buffer, filename, fileconfig)
         visited.remove(path)
-    def _build_config_wrapper(self, data, filename):
+    def build_fileconfig(self, data, filename):
         if sys.version_info.major >= 3:
             fileconfig = configparser.RawConfigParser(
                 strict=False, inline_comment_prefixes=(';', '#'))
         else:
             fileconfig = configparser.RawConfigParser()
         self._parse_config(data, filename, fileconfig, set())
-        return ConfigWrapper(self.printer, fileconfig, {}, 'printer')
+        return fileconfig
-    def _build_config_string(self, config):
+    def build_config_string(self, fileconfig):
         sfile = io.StringIO()
-        config.fileconfig.write(sfile)
+        fileconfig.write(sfile)
         return sfile.getvalue().strip()
-    def read_config(self, filename):
+
-        return self._build_config_wrapper(self._read_config_file(filename),
+
-                                          filename)
+######################################################################
-    def read_main_config(self):
+# Config auto save helper
+######################################################################
+
+AUTOSAVE_HEADER = """
+#*# <---------------------- SAVE_CONFIG ---------------------->
+#*# DO NOT EDIT THIS BLOCK OR BELOW. The contents are auto-generated.
+#*#
+"""
+
+class ConfigAutoSave:
+    def __init__(self, printer):
+        self.printer = printer
+        self.fileconfig = None
+        self.status_save_pending = {}
+        self.save_config_pending = False
+        gcode = self.printer.lookup_object('gcode')
+        gcode.register_command("SAVE_CONFIG", self.cmd_SAVE_CONFIG,
+                               desc=self.cmd_SAVE_CONFIG_help)
+    def _find_autosave_data(self, data):
+        regular_data = data
+        autosave_data = ""
+        pos = data.find(AUTOSAVE_HEADER)
+        if pos >= 0:
+            regular_data = data[:pos]
+            autosave_data = data[pos + len(AUTOSAVE_HEADER):].strip()
+        # Check for errors and strip line prefixes
+        if "\n#*# " in regular_data:
+            logging.warning("Can't read autosave from config file"
+                            " - autosave state corrupted")
+            return data, ""
+        out = [""]
+        for line in autosave_data.split('\n'):
+            if ((not line.startswith("#*#")
+                 or (len(line) >= 4 and not line.startswith("#*# ")))
+                and autosave_data):
+                logging.warning("Can't read autosave from config file"
+                                " - modifications after header")
+                return data, ""
+            out.append(line[4:])
+        out.append("")
+        return regular_data, "\n".join(out)
+    comment_r = re.compile('[#;].*$')
+    value_r = re.compile('[^A-Za-z0-9_].*$')
+    def _strip_duplicates(self, data, fileconfig):
+        # Comment out fields in 'data' that are defined in 'config'
+        lines = data.split('\n')
+        section = None
+        is_dup_field = False
+        for lineno, line in enumerate(lines):
+            pruned_line = self.comment_r.sub('', line).rstrip()
+            if not pruned_line:
+                continue
+            if pruned_line[0].isspace():
+                if is_dup_field:
+                    lines[lineno] = '#' + lines[lineno]
+                continue
+            is_dup_field = False
+            if pruned_line[0] == '[':
+                section = pruned_line[1:-1].strip()
+                continue
+            field = self.value_r.sub('', pruned_line)
+            if fileconfig.has_option(section, field):
+                is_dup_field = True
+                lines[lineno] = '#' + lines[lineno]
+        return "\n".join(lines)
+    def load_main_config(self):
         filename = self.printer.get_start_args()['config_file']
-        data = self._read_config_file(filename)
+        cfgrdr = ConfigFileReader()
+        data = cfgrdr.read_config_file(filename)
         regular_data, autosave_data = self._find_autosave_data(data)
-        regular_config = self._build_config_wrapper(regular_data, filename)
+        regular_fileconfig = cfgrdr.build_fileconfig(regular_data, filename)
-        autosave_data = self._strip_duplicates(autosave_data, regular_config)
+        autosave_data = self._strip_duplicates(autosave_data,
-        self.autosave = self._build_config_wrapper(autosave_data, filename)
+                                               regular_fileconfig)
-        cfg = self._build_config_wrapper(regular_data + autosave_data, filename)
+        self.fileconfig = cfgrdr.build_fileconfig(autosave_data, filename)
-        return cfg
+        return cfgrdr.build_fileconfig(regular_data + autosave_data, filename)
+    def get_status(self, eventtime):
+        return {'save_config_pending': self.save_config_pending,
+                'save_config_pending_items': self.status_save_pending}
+    def set(self, section, option, value):
+        if not self.fileconfig.has_section(section):
+            self.fileconfig.add_section(section)
+        svalue = str(value)
+        self.fileconfig.set(section, option, svalue)
+        pending = dict(self.status_save_pending)
+        if not section in pending or pending[section] is None:
+            pending[section] = {}
+        else:
+            pending[section] = dict(pending[section])
+        pending[section][option] = svalue
+        self.status_save_pending = pending
+        self.save_config_pending = True
+        logging.info("save_config: set [%s] %s = %s", section, option, svalue)
+    def remove_section(self, section):
+        if self.fileconfig.has_section(section):
+            self.fileconfig.remove_section(section)
+            pending = dict(self.status_save_pending)
+            pending[section] = None
+            self.status_save_pending = pending
+            self.save_config_pending = True
+        elif (section in self.status_save_pending and
+              self.status_save_pending[section] is not None):
+            pending = dict(self.status_save_pending)
+            del pending[section]
+            self.status_save_pending = pending
+            self.save_config_pending = True
+    def _disallow_include_conflicts(self, regular_data, cfgname, gcode):
+        cfgrdr = ConfigFileReader()
+        regular_fileconfig = cfgrdr.build_fileconfig(regular_data, cfgname)
+        for section in self.fileconfig.sections():
+            for option in self.fileconfig.options(section):
+                if regular_fileconfig.has_option(section, option):
+                    msg = ("SAVE_CONFIG section '%s' option '%s' conflicts "
+                           "with included value" % (section, option))
+                    raise gcode.error(msg)
+    cmd_SAVE_CONFIG_help = "Overwrite config file and restart"
+    def cmd_SAVE_CONFIG(self, gcmd):
+        if not self.fileconfig.sections():
+            return
+        gcode = self.printer.lookup_object('gcode')
+        # Create string containing autosave data
+        cfgrdr = ConfigFileReader()
+        autosave_data = cfgrdr.build_config_string(self.fileconfig)
+        lines = [('#*# ' + l).strip()
+                 for l in autosave_data.split('\n')]
+        lines.insert(0, "\n" + AUTOSAVE_HEADER.rstrip())
+        lines.append("")
+        autosave_data = '\n'.join(lines)
+        # Read in and validate current config file
+        cfgname = self.printer.get_start_args()['config_file']
+        try:
+            data = cfgrdr.read_config_file(cfgname)
+            regular_data, old_autosave_data = self._find_autosave_data(data)
+            regular_fileconfig = cfgrdr.build_fileconfig(regular_data, cfgname)
+        except error as e:
+            msg = "Unable to parse existing config on SAVE_CONFIG"
+            logging.exception(msg)
+            raise gcode.error(msg)
+        regular_data = self._strip_duplicates(regular_data, self.fileconfig)
+        self._disallow_include_conflicts(regular_data, cfgname, gcode)
+        data = regular_data.rstrip() + autosave_data
+        # Determine filenames
+        datestr = time.strftime("-%Y%m%d_%H%M%S")
+        backup_name = cfgname + datestr
+        temp_name = cfgname + "_autosave"
+        if cfgname.endswith(".cfg"):
+            backup_name = cfgname[:-4] + datestr + ".cfg"
+            temp_name = cfgname[:-4] + "_autosave.cfg"
+        # Create new config file with temporary name and swap with main config
+        logging.info("SAVE_CONFIG to '%s' (backup in '%s')",
+                     cfgname, backup_name)
+        try:
+            f = open(temp_name, 'w')
+            f.write(data)
+            f.close()
+            os.rename(cfgname, backup_name)
+            os.rename(temp_name, cfgname)
+        except:
+            msg = "Unable to write config file during SAVE_CONFIG"
+            logging.exception(msg)
+            raise gcode.error(msg)
+        # Request a restart
+        gcode.request_restart('restart')
+
+
+######################################################################
+# Main printer config tracking
+######################################################################
+
+class PrinterConfig:
+    def __init__(self, printer):
+        self.printer = printer
+        self.autosave = ConfigAutoSave(printer)
+        self.deprecated = {}
+        self.runtime_warnings = []
+        self.deprecate_warnings = []
+        self.status_raw_config = {}
+        self.status_settings = {}
+        self.status_warnings = []
+    def get_printer(self):
+        return self.printer
+    def read_config(self, filename):
+        cfgrdr = ConfigFileReader()
+        data = cfgrdr.read_config_file(filename)
+        fileconfig = cfgrdr.build_fileconfig(data, filename)
+        return ConfigWrapper(self.printer, fileconfig, {}, 'printer')
+    def read_main_config(self):
+        fileconfig = self.autosave.load_main_config()
+        return ConfigWrapper(self.printer, fileconfig, {}, 'printer')
     def check_unused_options(self, config):
         fileconfig = config.fileconfig
         objects = dict(self.printer.lookup_objects())
@@ -312,8 +432,9 @@ class PrinterConfig:
         # Setup get_status()
         self._build_status(config)
     def log_config(self, config):
+        cfgrdr = ConfigFileReader()
         lines = ["===== Config file =====",
-                 self._build_config_string(config),
+                 cfgrdr.build_config_string(config.fileconfig),
                  "======================="]
         self.printer.set_rollover_info("config", "\n".join(lines))
     # Status reporting
@@ -345,91 +466,13 @@ class PrinterConfig:
             self.deprecate_warnings.append(res)
         self.status_warnings = self.runtime_warnings + self.deprecate_warnings
     def get_status(self, eventtime):
-        return {'config': self.status_raw_config,
+        status = {'config': self.status_raw_config,
                   'settings': self.status_settings,
-                'warnings': self.status_warnings,
+                  'warnings': self.status_warnings}
-                'save_config_pending': self.save_config_pending,
+        status.update(self.autosave.get_status(eventtime))
-                'save_config_pending_items': self.status_save_pending}
+        return status
     # Autosave functions
     def set(self, section, option, value):
-        if not self.autosave.fileconfig.has_section(section):
+        self.autosave.set(section, option, value)
-            self.autosave.fileconfig.add_section(section)
-        svalue = str(value)
-        self.autosave.fileconfig.set(section, option, svalue)
-        pending = dict(self.status_save_pending)
-        if not section in pending or pending[section] is None:
-            pending[section] = {}
-        else:
-            pending[section] = dict(pending[section])
-        pending[section][option] = svalue
-        self.status_save_pending = pending
-        self.save_config_pending = True
-        logging.info("save_config: set [%s] %s = %s", section, option, svalue)
     def remove_section(self, section):
-        if self.autosave.fileconfig.has_section(section):
+        self.autosave.remove_section(section)
-            self.autosave.fileconfig.remove_section(section)
-            pending = dict(self.status_save_pending)
-            pending[section] = None
-            self.status_save_pending = pending
-            self.save_config_pending = True
-        elif (section in self.status_save_pending and
-              self.status_save_pending[section] is not None):
-            pending = dict(self.status_save_pending)
-            del pending[section]
-            self.status_save_pending = pending
-            self.save_config_pending = True
-    def _disallow_include_conflicts(self, regular_data, cfgname, gcode):
-        config = self._build_config_wrapper(regular_data, cfgname)
-        for section in self.autosave.fileconfig.sections():
-            for option in self.autosave.fileconfig.options(section):
-                if config.fileconfig.has_option(section, option):
-                    msg = ("SAVE_CONFIG section '%s' option '%s' conflicts "
-                           "with included value" % (section, option))
-                    raise gcode.error(msg)
-    cmd_SAVE_CONFIG_help = "Overwrite config file and restart"
-    def cmd_SAVE_CONFIG(self, gcmd):
-        if not self.autosave.fileconfig.sections():
-            return
-        gcode = self.printer.lookup_object('gcode')
-        # Create string containing autosave data
-        autosave_data = self._build_config_string(self.autosave)
-        lines = [('#*# ' + l).strip()
-                 for l in autosave_data.split('\n')]
-        lines.insert(0, "\n" + AUTOSAVE_HEADER.rstrip())
-        lines.append("")
-        autosave_data = '\n'.join(lines)
-        # Read in and validate current config file
-        cfgname = self.printer.get_start_args()['config_file']
-        try:
-            data = self._read_config_file(cfgname)
-            regular_data, old_autosave_data = self._find_autosave_data(data)
-            config = self._build_config_wrapper(regular_data, cfgname)
-        except error as e:
-            msg = "Unable to parse existing config on SAVE_CONFIG"
-            logging.exception(msg)
-            raise gcode.error(msg)
-        regular_data = self._strip_duplicates(regular_data, self.autosave)
-        self._disallow_include_conflicts(regular_data, cfgname, gcode)
-        data = regular_data.rstrip() + autosave_data
-        # Determine filenames
-        datestr = time.strftime("-%Y%m%d_%H%M%S")
-        backup_name = cfgname + datestr
-        temp_name = cfgname + "_autosave"
-        if cfgname.endswith(".cfg"):
-            backup_name = cfgname[:-4] + datestr + ".cfg"
-            temp_name = cfgname[:-4] + "_autosave.cfg"
-        # Create new config file with temporary name and swap with main config
-        logging.info("SAVE_CONFIG to '%s' (backup in '%s')",
-                     cfgname, backup_name)
-        try:
-            f = open(temp_name, 'w')
-            f.write(data)
-            f.close()
-            os.rename(cfgname, backup_name)
-            os.rename(temp_name, cfgname)
-        except:
-            msg = "Unable to write config file during SAVE_CONFIG"
-            logging.exception(msg)
-            raise gcode.error(msg)
-        # Request a restart
-        gcode.request_restart('restart')