1 files changed, 33 insertions, 15 deletions

diff --git a/pyasn1/codec/ber/encoder.py b/pyasn1/codec/ber/encoder.py
index 778aa86..6b77b70 100644
--- a/pyasn1/codec/ber/encoder.py
+++ b/pyasn1/codec/ber/encoder.py
@@ -17,7 +17,7 @@ from pyasn1.type import tag
 from pyasn1.type import univ
 from pyasn1.type import useful
 
-__all__ = ['encode']
+__all__ = ['Encoder', 'encode']
 
 LOG = debug.registerLoggee(__name__, flags=debug.DEBUG_ENCODER)
 
@@ -706,7 +706,7 @@ class AnyEncoder(OctetStringEncoder):
         return value, not options.get('defMode', True), True
 
 
-tagMap = {
+TAG_MAP = {
     eoo.endOfOctets.tagSet: EndOfOctetsEncoder(),
     univ.Boolean.tagSet: BooleanEncoder(),
     univ.Integer.tagSet: IntegerEncoder(),
@@ -739,7 +739,7 @@ tagMap = {
 }
 
 # Put in ambiguous & non-ambiguous types for faster codec lookup
-typeMap = {
+TYPE_MAP = {
     univ.Boolean.typeId: BooleanEncoder(),
     univ.Integer.typeId: IntegerEncoder(),
     univ.BitString.typeId: BitStringEncoder(),
@@ -774,14 +774,16 @@ typeMap = {
 }
 
 
-class Encoder(object):
+class SingleItemEncoder(object):
     fixedDefLengthMode = None
     fixedChunkSize = None
 
-    # noinspection PyDefaultArgument
-    def __init__(self, tagMap, typeMap={}):
-        self.__tagMap = tagMap
-        self.__typeMap = typeMap
+    TAG_MAP = TAG_MAP
+    TYPE_MAP = TYPE_MAP
+
+    def __init__(self, tagMap=None, typeMap=None):
+        self.__tagMap = tagMap or self.TAG_MAP
+        self.__typeMap = typeMap or self.TYPE_MAP
 
     def __call__(self, value, asn1Spec=None, **options):
         try:
@@ -795,8 +797,11 @@ class Encoder(object):
                                     'and "asn1Spec" not given' % (value,))
 
         if LOG:
-            LOG('encoder called in %sdef mode, chunk size %s for '
-                   'type %s, value:\n%s' % (not options.get('defMode', True) and 'in' or '', options.get('maxChunkSize', 0), asn1Spec is None and value.prettyPrintType() or asn1Spec.prettyPrintType(), value))
+            LOG('encoder called in %sdef mode, chunk size %s for type %s, '
+                'value:\n%s' % (not options.get('defMode', True) and 'in' or '',
+                                options.get('maxChunkSize', 0),
+                                asn1Spec is None and value.prettyPrintType() or
+                                asn1Spec.prettyPrintType(), value))
 
         if self.fixedDefLengthMode is not None:
             options.update(defMode=self.fixedDefLengthMode)
@@ -804,12 +809,12 @@ class Encoder(object):
         if self.fixedChunkSize is not None:
             options.update(maxChunkSize=self.fixedChunkSize)
 
-
         try:
             concreteEncoder = self.__typeMap[typeId]
 
             if LOG:
-                LOG('using value codec %s chosen by type ID %s' % (concreteEncoder.__class__.__name__, typeId))
+                LOG('using value codec %s chosen by type ID '
+                    '%s' % (concreteEncoder.__class__.__name__, typeId))
 
         except KeyError:
             if asn1Spec is None:
@@ -827,15 +832,28 @@ class Encoder(object):
                 raise error.PyAsn1Error('No encoder for %r (%s)' % (value, tagSet))
 
             if LOG:
-                LOG('using value codec %s chosen by tagSet %s' % (concreteEncoder.__class__.__name__, tagSet))
+                LOG('using value codec %s chosen by tagSet '
+                    '%s' % (concreteEncoder.__class__.__name__, tagSet))
 
         substrate = concreteEncoder.encode(value, asn1Spec, self, **options)
 
         if LOG:
-            LOG('codec %s built %s octets of substrate: %s\nencoder completed' % (concreteEncoder, len(substrate), debug.hexdump(substrate)))
+            LOG('codec %s built %s octets of substrate: %s\nencoder '
+                'completed' % (concreteEncoder, len(substrate),
+                               debug.hexdump(substrate)))
 
         return substrate
 
+
+class Encoder(object):
+    SINGLE_ITEM_ENCODER = SingleItemEncoder
+
+    @classmethod
+    def __call__(cls, pyObject, asn1Spec=None, **options):
+        singleItemEncoder = cls.SINGLE_ITEM_ENCODER()
+        return singleItemEncoder(pyObject, asn1Spec=asn1Spec, **options)
+
+
 #: Turns ASN.1 object into BER octet stream.
 #:
 #: Takes any ASN.1 object (e.g. :py:class:`~pyasn1.type.base.PyAsn1Item` derivative)
@@ -887,4 +905,4 @@ class Encoder(object):
 #:    >>> encode(seq)
 #:    b'0\t\x02\x01\x01\x02\x01\x02\x02\x01\x03'
 #:
-encode = Encoder(tagMap, typeMap)
+encode = Encoder()