configfile: Add support for rewriting the printer config file

Add support for writing back the main printer config file with
additional calibration data stored in it.

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

docs/G-Codes.md

@@ -115,6 +115,10 @@ The following standard commands are supported:
   [the FAQ](FAQ.md#how-do-i-upgrade-to-the-latest-software)).
 - `FIRMWARE_RESTART`: This is similar to a RESTART command, but it
   also clears any error state from the micro-controller.
+- `SAVE_CONFIG`: This command will overwrite the main printer config
+  file and restart the host software. This command is used in
+  conjunction with other calibration commands to store the results of
+  calibration tests.
 - `STATUS`: Report the Klipper host software status.
 - `HELP`: Report the list of available extended G-Code commands.
 

klippy/configfile.py

@@ -1,9 +1,9 @@
-# Code for reading the Klipper config file
+# Code for reading and writing the Klipper config file
 #
 # Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
-import ConfigParser
+import os, re, time, logging, ConfigParser, StringIO
 
 error = ConfigParser.Error
 
@@ -75,31 +75,104 @@ class ConfigWrapper:
         return [self.getsection(s) for s in self.fileconfig.sections()
                 if s.startswith(prefix)]
 
-class ConfigLogger:
+AUTOSAVE_HEADER = """
-    def __init__(self, fileconfig, printer):
+#*# <---------------------- SAVE_CONFIG ---------------------->
-        self.lines = ["===== Config file ====="]
+#*# DO NOT EDIT THIS BLOCK OR BELOW. The contents are auto-generated.
-        fileconfig.write(self)
+#*#
-        self.lines.append("=======================")
+"""
-        printer.set_rollover_info("config", "\n".join(self.lines))
-    def write(self, data):
-        self.lines.append(data.strip())
 
 class PrinterConfig:
     def __init__(self, printer):
         self.printer = printer
-    def read_config(self, filename):
+        self.autosave = None
+        gcode = self.printer.lookup_object('gcode')
+        gcode.register_command("SAVE_CONFIG", self.cmd_SAVE_CONFIG,
+                               desc=self.cmd_SAVE_CONFIG_help)
+    def _read_config_file(self, filename):
+        try:
+            f = open(filename, 'rb')
+            data = f.read()
+            f.close()
+        except:
+            msg = "Unable to open config file %s" % (filename,)
+            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.warn("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.warn("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):
+        fileconfig = config.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 config.fileconfig.has_option(section, field):
+                is_dup_field = True
+                lines[lineno] = '#' + lines[lineno]
+        return "\n".join(lines)
+    def _build_config_wrapper(self, data):
+        sfile = StringIO.StringIO(data)
         fileconfig = ConfigParser.RawConfigParser()
-        res = fileconfig.read(filename)
+        fileconfig.readfp(sfile)
-        if not res:
-            raise error("Unable to open config file %s" % (filename,))
         return ConfigWrapper(self.printer, fileconfig, {}, 'printer')
+    def _build_config_string(self, config):
+        sfile = StringIO.StringIO()
+        config.fileconfig.write(sfile)
+        return sfile.getvalue().strip()
+    def read_config(self, filename):
+        return self._build_config_wrapper(self._read_config_file(filename))
     def read_main_config(self):
         filename = self.printer.get_start_args()['config_file']
-        return self.read_config(filename)
+        data = self._read_config_file(filename)
+        regular_data, autosave_data = self._find_autosave_data(data)
+        regular_config = self._build_config_wrapper(regular_data)
+        autosave_data = self._strip_duplicates(autosave_data, regular_config)
+        self.autosave = self._build_config_wrapper(autosave_data)
+        return self._build_config_wrapper(regular_data + autosave_data)
     def check_unused_options(self, config):
-        access_tracking = config.access_tracking
         fileconfig = config.fileconfig
         objects = dict(self.printer.lookup_objects())
+        # Determine all the fields that have been accessed
+        access_tracking = dict(config.access_tracking)
+        for section in self.autosave.fileconfig.sections():
+            for option in self.autosave.fileconfig.options(section):
+                access_tracking[(section.lower(), option.lower())] = 1
         # Validate that there are no undefined parameters in the config file
         valid_sections = { s: 1 for s, o in access_tracking }
         for section_name in fileconfig.sections():
@@ -113,4 +186,62 @@ class PrinterConfig:
                     raise error("Option '%s' is not valid in section '%s'" % (
                         option, section))
     def log_config(self, config):
-        ConfigLogger(config.fileconfig, self.printer)
+        lines = ["===== Config file =====",
+                 self._build_config_string(config),
+                 "======================="]
+        self.printer.set_rollover_info("config", "\n".join(lines))
+    # Autosave functions
+    def set(self, section, option, value):
+        if not self.autosave.fileconfig.has_section(section):
+            self.autosave.fileconfig.add_section(section)
+        svalue = str(value)
+        self.autosave.fileconfig.set(section, option, svalue)
+        logging.info("save_config: set [%s] %s = %s", section, option, svalue)
+    def remove_section(self, section):
+        self.autosave.fileconfig.remove_section(section)
+    cmd_SAVE_CONFIG_help = "Overwrite config file and restart"
+    def cmd_SAVE_CONFIG(self, params):
+        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)
+        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)
+        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, 'wb')
+            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')