more work on decoding #5 DCP messages. now if character 37 is not blank

render message as-is (binary) otherwise do the normal substitutions.

Author: petersilva

opendcs-acquisition/INSTALL.md

@@ -206,6 +206,14 @@ eventually it gets posted:
 
 ```
 
+## Data Encoding
+
+* based on python string method: .decode('unicode-escape') expands all the \077 octal characters to ASCII equivalents.
+* replace \r and \n with line-feed and carriage-return respectively.
+* trip trailing spaces on each line.
+* ignore \f (formfeed) and \t (tab) and any other escape codes.
+* not sure what happens with \\ I think nothing.
+
 
 ## Maintenance Activities
 

opendcs-acquisition/config/sr3/plugins/dcpflow.py

@@ -360,6 +360,7 @@ def gather(self):
                     hh=raw_line[13:15]
                     mm=raw_line[15:17]
                     rnd="%05d" % random.randint(1,10000)
+                    is_plaintext= (raw_line[37] == ' ')
 
                     subdir=os.path.join( self.o.variableExpansion(self.o.directory), \
                             f"{RxTime.year}{RxTime.month:02d}{RxTime.day:02d}", f"{self.o.source}", \
@@ -368,16 +369,19 @@ def gather(self):
                         os.makedirs( subdir ) 
 
                     BulletinFile=os.path.join( subdir, f"{Ahl}_{dd}{hh}{mm}_{rnd}" )
-                    bf=open(BulletinFile,'w')
+                    bf=open(BulletinFile,'wb')
                     #logger.info( f"writing: {BulletinFile}" )
-                    bf.write( f"{Ahl.replace('_',' ')} {dd}{hh}{mm}\r\r\n" )
+                    bf.write( f"{Ahl.replace('_',' ')} {dd}{hh}{mm}\r\r\n".encode('latin1') )
                 except Exception as ex:
                     logger.error( "problem reading ob", exc_info=True )
                     continue
-            for l in raw_line.split('\\n'):
-                #l=l.replace('\\r','').replace('\\\\','\\').strip()+'\r\n'
-                l=l.replace('\\r','').strip()+'\r\n'
-                bf.write(l)
+
+            if is_plaintext:
+                for l in raw_line.split('\\n'):
+                    l=l.replace('\\r','\r').strip()+'\n'
+                    bf.write(l.encode('latin1'))
+            else:
+                    bf.write(byte_line)
 
         if bf:
             bf.close()