#4070 Add function to read any Allsky variable

Author: Alex-developer

scripts/modules/allsky_shared.py

@@ -22,6 +22,8 @@
 import argparse
 import locale
 import tempfile
+import pathlib
+from pathlib import Path
 
 try:
     locale.setlocale(locale.LC_ALL, '')
@@ -49,7 +51,6 @@ def getEnvironmentVariable(name, fatal=False):
 SETTINGS_FILE = getEnvironmentVariable("SETTINGS_FILE", fatal=True)
 ALLSKY_OVERLAY = getEnvironmentVariable("ALLSKY_OVERLAY", fatal=True)
 
-
 LOGLEVEL = 0
 SETTINGS = {}
 TOD = ''
@@ -159,7 +160,6 @@ def convertPath(path):
 
     return path
 
-
 def startModuleDebug(module):
     global ALLSKY_TMP
 
@@ -172,7 +172,6 @@ def startModuleDebug(module):
     except:
         log(0, f"ERROR: Unable to create {moduleTmpDir}")
 
-
 def writeDebugImage(module, fileName, image):
     global ALLSKY_TMP
 
@@ -182,7 +181,6 @@ def writeDebugImage(module, fileName, image):
     cv2.imwrite(moduleTmpFile, image, params=None)
     log(4,"INFO: Wrote debug file {0}".format(moduleTmpFile))
 
-
 def setEnvironmentVariable(name, value, logMessage='', logLevel=4):
     result = True
 
@@ -196,7 +194,6 @@ def setEnvironmentVariable(name, value, logMessage='', logLevel=4):
 
     return result
 
-
 def setupForCommandLine():
     global ALLSKYPATH
 
@@ -253,11 +250,9 @@ def updateSetting(values):
 
     writeSettings()
 
-
 def var_dump(variable):
     pprint.PrettyPrinter(indent=2, width=128).pprint(variable)
 
-
 def log(level, text, preventNewline = False, exitCode=None, sendToAllsky=False):
     """ Very simple method to log data if in verbose mode """
     global LOGLEVEL, ALLSKY_SCRIPTS
@@ -370,7 +365,6 @@ def asfloat(val):
 
     return val
 
-
 def getExtraDir():
     return getEnvironmentVariable("ALLSKY_EXTRA", fatal=True)
 
@@ -390,7 +384,6 @@ def validateExtraFileName(params, module, fileKey):
 
     params[fileKey] = extraDataFilename
 
-
 def save_extra_data(file_name, extra_data):
     saveExtraData(file_name, extra_data)
 
@@ -554,3 +547,86 @@ def getGPIOPin(pin):
         result = board.D27
 
     return result
+
+
+def _get_value_from_json_file(file_path, variable):
+    """
+    Loads a json based extra data file and returns the value of a variable if found
+
+    Args:
+        variable (string): The varible to get
+
+    Returns:
+        result (various) The result or None if the variable could not be found
+    """
+    result = None
+    try:
+        with open(file_path, encoding='utf-8') as file:
+            json_data = json.load(file)
+            for (name, value_data) in json_data.items():
+                if name == variable:
+                    if isinstance(value_data, dict):
+                        if 'value' in value_data:
+                            result = value_data['value']
+                    else:
+                        result = value_data
+    except: # pylint: disable=W0702
+        pass
+
+    return result
+
+def _get_value_from_text_file(file_path, variable):
+    """
+    Loads a text based extra data file and returns the value of a variable if found
+
+    Args:
+        variable (string): The varible to get
+
+    Returns:
+        result (various) The result or None if the variable could not be found
+    """
+    result = None
+
+    with open(file_path, encoding='utf-8') as file:
+        for line in file:
+            name, value = line.partition("=")[::2]
+            name = name.rstrip()
+            value = value.lstrip()
+            value = value.strip()
+            if name == variable:
+                result = value
+                break
+
+    return result   
+
+def get_allsky_variable(variable):
+    """
+    Gets an Allsky variable either from the environment or extra data files
+
+    Args:
+        variable (string): The varible to get
+
+    Returns:
+        result (various) The result or None if the variable could not be found
+    """
+    result = getEnvironmentVariable(variable)
+
+    if result is None:
+        extra_data_path = getExtraDir()
+        directory = Path(extra_data_path)
+
+        for file_path in directory.iterdir():
+            if file_path.is_file() and isFileReadable(file_path):
+
+                file_extension = Path(file_path).suffix
+
+                if file_extension == '.json':
+                    result = _get_value_from_json_file(file_path, variable)
+
+                if file_extension == '.txt':
+                    result = _get_value_from_text_file(file_path, variable)
+
+            if result is not None:
+                break
+
+    return result