Draft backend class

__init__.py

+from __future__ import print_function
+
+import logging
+import subprocess
+from configparser import ConfigParser
+import os.path
+import time
+
+config = ConfigParser()
+config.readfp(open(os.path.join(os.path.dirname(__file__), 'backend.ini')))
+
+logging.basicConfig(level=logging.DEBUG)
+
+class Backend():
+    def __init__(self,currentMode='Pulsar', setmode=None):
+        '''
+        Initializes a backend instance. The mode for writing can be
+        Pulsar', 'Line','Raw' or 'SDR'.
+        '''
+        self.runimpactTool = config.get('Tools','runimpact')
+        self.LSRTool = config.get('Tools', 'vlsr')
+        self.LSREnabled = False
+        if setmode not in ('Pulsar', 'Hydrogen', 'Raw', 'SDR', None):
+            raise ValueError("Mode must be 'Pulsar', 'Hydrogen', 'Raw', 'SDR':" + setmode)
+        self.setmode = setmode
+        self.currentMode = currentMode
+        self.runImpact = False
+       
+        logging.info('Backend Intiatialised in mode: {}'.format(self.setmode))
+        logging.info('VLSR initialized in mode: {}'.format(self.LSREnabled))
+    
+    def setMode(self, setmode):
+        '''
+        Compile CLI and execute command
+        '''
+        self.setmode = setmode
+        self.runImpact = False
+        logging.debug('Current Mode: {} \t SetMode: {}'.format(self.currentMode,self.setmode))
+        if self.currentMode is not self.setmode:
+            self.currentMode = setmode
+            self.runImpact = True
+        
+        if self.runImpact==True:
+                
+            if self.setmode == 'Pulsar':
+                argument = config.get('Modes','Pulsar')
+        
+            if self.setmode == 'Hydrogen':
+                argument = config.get('Modes','Hydrogen')
+            
+            if self.setmode == 'Raw':
+                argument = config.get('Modes','Raw')
+        
+            if self.setmode == 'SDR':
+                argument = config.get('Modes','SDR')
+         
+            logging.info('Excute CLI: {} {}'.format(self.runimpactTool, argument))
+        
+            '''
+            Note: in the stub runimpact I added /bin/bash, otherwise you get an Exec format error.
+            '''
+            self.cli = subprocess.Popen(self.runimpactTool, 10, stdout=subprocess.PIPE)
+            self.cli.wait()
+            logging.info('runimpact completed')
+            
+        else:
+            logging.info('Backend already in {} mode'.format(self.currentMode))
+        
+    def enableLSR(self):
+        '''
+        Compile CLI and execute command
+        Note: in the stub runimpact I added /bin/bash, otherwise you get an Exec format error.
+        '''
+        if self.LSREnabled == False: 
+            self.cli = subprocess.Popen(self.LSRTool, stdout=subprocess.PIPE)
+            self.cli.wait()
+            self.LSREnabled = True
+            logging.info('LSR compensation is enabled')
+        else:
+            logging.info('LSR is already enabled')
+            
+if __name__ == '__main__':
+    myBackend = Backend()
+    myBackend.enableLSR()
+    myBackend.enableLSR()
+    myBackend.setMode('Pulsar')
+    myBackend.setMode('Hydrogen')
+    myBackend.setMode('Hydrogen')
+    myBackend.setMode('Raw')
+    myBackend.setMode('Raw')
+    myBackend.setMode('SDR')
+    myBackend.setMode('SDR')
+    myBackend.setMode('Pulsar')    
+    
+    
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backend.ini

+[Tools]
+runimpact: /home/marc/bin/runimpact
+vlsr: /home/marc/bin/trackHI.py
+
+[Modes]
+pulsar: pulsar.batch
+hydrogen: line
+raw: raw
+SDR: sdr
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