rclrar: also support py-unrar

src/filters/rclrar

@@ -22,10 +22,23 @@ from __future__ import print_function
 
 import sys
 import rclexecm
+import os
+
+# We can use two different unrar python modules. Either python-rarfile
+# which is a wrapper over the the unrar command line, or python-unrar
+# which is a ctypes wrapper of the unrar lib. Python-rarfile is the
+# one commonly packaged on linux. Their interfaces is similar. Note
+# that python-unrar uses forward slashes in internal file paths while
+# python-rarfile uses backslashes (ipaths are opaque anyway).
+using_unrar = False
+try:
+    from unrar import rarfile
+    using_unrar = True
+except Exception as ex:
     try:
         from rarfile import RarFile
     except:
-    print("RECFILTERROR HELPERNOTFOUND python3:rarfile")
+        print("RECFILTERROR HELPERNOTFOUND python3:rarfile/python3:unrar")
         sys.exit(1);
 
 # Requires RarFile python module. Try "sudo pip install rarfile" or
@@ -49,10 +62,14 @@ class RarExtractor:
         
         try:
             rarinfo = self.rar.getinfo(ipath)
+            if using_unrar:
+                # dll.hpp RHDF_DIRECTORY: 0x20
+                isdir = ((rarinfo.flag_bits & 0x20) != 0)
+            else:
                 isdir = rarinfo.isdir()
         except Exception as err:
             self.em.rclog("extractone: rar.getinfo failed: [%s]" % err)
-            return (True, docdata, ipath, false)
+            return (True, docdata, ipath, False)
 
         if not isdir:
             try:
@@ -80,6 +97,14 @@ class RarExtractor:
     def openfile(self, params):
         self.currentindex = -1
         try:
+            if using_unrar:
+                # There might be a way to avoid the decoding which is
+                # wrong on Unix, but I'd have to dig further in the
+                # lib than I wish to. This is used on Windows anyway,
+                # where all Recoll paths are utf-8
+                fn = params["filename:"].decode("UTF-8")
+                self.rar = rarfile.RarFile(fn, 'rb')
+            else:
                 # The previous versions passed the file name to
                 # RarFile. But the py3 version of this wants an str as
                 # input, which is wrong of course, as filenames are