Classe ConfigPyros pour lire les fichiers XML de configuration

Alain Klotz
1 parent 18f847bf
Showing 1 changed file with 202 additions and 0 deletions Show diff stats
config/configpyros.py
@@ -0,0 +1,202 @@
+# python c:\srv\develop\pyros\config\configpyros.py
+# ----------------------------------------------------------------------------------------------------
+# Parameter attributes = section, key, value, type, unit, access, comment, label, reference, timestamp
+# ----------------------------------------------------------------------------------------------------
+from lxml import etree
+import os
+
+class ConfigPyros:
+    
+    # === Constants
+    NO_ERROR = 0
+    ERR_FILE_NOT_EXISTS = 100
+    ERR_LOAD_ERROR = 200
+    ERR_TAG_ROOT_IS_NOT_UNIT = 201
+    ERR_TAG_ROOT_HAS_NO_ATTRIBUTE_ALIAS = 202
+
+    # === Private variables
+    _last_errno = NO_ERROR
+    _config_filename = ""
+    _config_filename_mtime = 0
+    _config_filename_need_to_be_read = True
+    _unit_component_params = []
+    _unit_component_params_valid = False
+    
+    def get_last_errno(self):
+        """ Get the last error code
+        """
+        return self._last_errno
+        
+    def set_configfile(self, config_filename:str ):
+        """ To set the config file name
+        
+        :param config_filename: A string that contains the full name of the configuration file.
+        :type config_filename: string
+        """
+        if config_filename == "" or config_filename != self._config_filename:
+            self._config_filename = config_filename
+            self._config_filename_mtime = 0
+            self._unit_component_params_valid = False
+            self._unit_component_params = []
+        self._configfile_verify()
+        return
+        
+    def get_configfile(self):
+        """ Get the current config file name
+        """
+        return self._config_filename
+        
+    def _configfile_verify(self):
+        """ Update parameters of the configuration file (existing, modification date)
+        """
+        self._config_filename_need_to_be_read = False
+        self._last_errno = self.NO_ERROR
+        if os.path.isfile(self._config_filename):
+            # --- verify the date of last modification of the file
+            config_filename_mtime = os.path.getmtime(self._config_filename)
+            if config_filename_mtime > self._config_filename_mtime:
+                self._config_filename_need_to_be_read = True                
+                #### self._config_filename_mtime = config_filename_mtime
+        else:
+            self._last_errno = self.ERR_FILE_NOT_EXISTS
+    
+    
+    def load(self, verbose:bool = False):
+        """ To load the config file if necessary
+        
+        :Example:
+            
+        ConfigPyros().load()
+        """
+
+        self._configfile_verify()
+        errno = config.get_last_errno()
+        if errno != config.NO_ERROR:
+            return
+        if self._config_filename_need_to_be_read == False:
+            return
+
+        # --- Read the configuration file and parse it
+        self._last_errno = self.NO_ERROR
+        unit_component_params = []
+        try:
+            tree = etree.parse(self._config_filename)
+            # --- Get root from the tree
+            root = tree.getroot()
+
+            # === Verify the root tag is 'unit'
+            verify_unit = root.tag
+            if (verify_unit != "unit"):
+                self._last_errno = self.ERR_TAG_ROOT_IS_NOT_UNIT
+                return
+                
+            # === Get the alias value of the root tag 'unit'
+            alias_unit = root.attrib['alias']
+            if (alias_unit == ""):
+                self._last_errno = self.ERR_TAG_ROOT_HAS_NO_ATTRIBUTE_ALIAS
+                return
+            
+            # === Get the mount aliases
+            alias_mounts = []
+            for elem in root.xpath("/unit/mount"):
+                # print(elem.tag, elem.attrib)
+                alias_mounts.append(elem.attrib['alias'])
+            if (verbose==True):
+                print("alias_mounts = {}".format(alias_mounts))
+
+            # === Get the channel aliases
+            alias_channels = []
+            for elem in root.xpath("/unit/channel"):
+                # print(elem.tag, elem.attrib)
+                alias_channels.append(elem.attrib['alias'])
+            if (verbose==True):
+                print("alias_channels = {}".format(alias_channels))
+
+            # === Get the association of channels for this mount
+            unit_components = []
+            for elem in root:
+                if elem.tag == "param":
+                    attributes = elem.attrib
+                    if attributes['section'] != "instanciation":
+                        continue
+                    alias_param_unit = attributes['value']
+                    for alias_mount in alias_mounts:
+                        if alias_param_unit == alias_mount:
+                            key = attributes['key']
+                            dico = {'tag':'mount','instanciation':key,'alias':alias_param_unit}
+                            unit_components.append(dico)
+                    for alias_channel in alias_channels:
+                        if alias_param_unit == alias_channel:
+                            key = attributes['key']
+                            dico = {'tag':'channel','instanciation':key,'alias':alias_param_unit}
+                            unit_components.append(dico)
+            if (verbose==True):
+                print("unit_components = {}".format(unit_components))
+
+            # === Get detailed informations about the unit components
+            for unit_component in unit_components:
+                tag = unit_component['tag']
+                instanciation = unit_component['instanciation']
+                alias = unit_component['alias']
+                params = []
+                for elem in root:
+                    if (elem.tag == tag) and (elem.attrib['alias'] == alias):
+                        for el in elem:
+                            if (el.tag == "param"):
+                                params.append(el.attrib)
+                unit_component_params.append({'component':tag, 'instanciation':instanciation, 'alias':alias, 'params':params})
+            if (verbose==True):
+                print("unit_component_params = {}".format(unit_component_params))
+            self._unit_component_params = unit_component_params
+            self._unit_component_params_valid = True
+            self._config_filename_mtime = os.path.getmtime(self._config_filename)
+        except:
+            self._last_errno = self.ERR_LOAD_ERROR
+        return
+    
+    def get_paramvalue(self, instanciation:str, section:str, key:str):
+        if self._unit_component_params_valid == False:
+            return ""
+        unit_component_params = self._unit_component_params
+        paramvalue = ""
+        for unit_component_param in unit_component_params:
+            component_instanciation = unit_component_param['instanciation']
+            if (component_instanciation == instanciation):
+                for param in unit_component_param['params']:
+                    param_section = param['section']
+                    param_key = param['key']
+                    if (param_section == section) and (param_key == key):
+                        paramvalue = param['value']
+                        break
+                if (paramvalue != ""):
+                    break
+        return paramvalue
+    
+    def __init__(self, config_filename:str = ""):
+        self._last_errno = self.NO_ERROR
+        self._unit_component_params = []
+        self.set_configfile(config_filename)
+    
+if __name__ == "__main__":
+    # --- Set the filename of the configuration
+    config_filename = 'c:/srv/develop/pyros/config/config_unit_simulunit1.xml'
+    #config_filename = '/PROJECTS/GFT/SOFT/PYROS_SOFT/CURRENT/config/config_unit_simulunit1.xml'
+    # --- Instanciate an object for configuration
+    config = ConfigPyros(config_filename)
+    #config.set_configfile(config_filename)
+    if config.get_last_errno() != config.NO_ERROR:
+        print("Error code = {}".format(config.get_last_errno()))
+    else:     
+        # --- Load the configuration file if needed only (i.e. modified)
+        config.load()
+        # --- get the parameter value of <mount1/localization/home>
+        instanciation = 'mount1'
+        section = 'localization'
+        key = 'home'
+        paramvalue = config.get_paramvalue(instanciation, section, key)
+        print("paramvalue <{}/{}/{}> = {}".format(instanciation, section, key,paramvalue))
+        #
+        #print("unit_component_params = {}".format(unit_component_params))
+        #component = unit_component_params[0]
+        #params = component['params']
+        #print("params = {}".format(params))