pulled code from django-compressor and removed it as dependency

demoapp/.coveragerc

@@ -5,3 +5,6 @@ omit =
     */sendmail/tests/*
     */sendmail/admin/*
     */demoapp/*
+    */sendmail/django_compressor.py
+    */sendmail/config.py
+    */sendmail/checks.py

demoapp/tests/requirements/test_requirements.txt

@@ -12,4 +12,3 @@ pytest-cov
 redis
 requests
 django-jsoneditor
-django-compressor

requirements.txt

@@ -94,4 +94,3 @@ webencodings==0.5.1
 wheel==0.44.0
 zipp==3.20.0
 django-jsoneditor==0.2.4
-django-compressor==4.5.1

sendmail/django_compressor.py

@@ -0,0 +1,93 @@
+from copy import copy
+
+from django.template.base import VariableNode, TextNode, NodeList
+from django.template.defaulttags import IfNode
+from django.template.loader_tags import (
+    BLOCK_CONTEXT_KEY,
+    ExtendsNode,
+    BlockNode,
+    BlockContext,
+)
+
+
+
+def handle_extendsnode(extendsnode, context):
+    """Create a copy of Node tree of a derived template replacing
+    all blocks tags with the nodes of appropriate blocks.
+    Also handles {{ block.super }} tags.
+    """
+    if BLOCK_CONTEXT_KEY not in context.render_context:
+        context.render_context[BLOCK_CONTEXT_KEY] = BlockContext()
+    block_context = context.render_context[BLOCK_CONTEXT_KEY]
+    blocks = dict(
+        (n.name, n) for n in extendsnode.nodelist.get_nodes_by_type(BlockNode)
+    )
+    block_context.add_blocks(blocks)
+
+    compiled_parent = extendsnode.get_parent(context)
+    parent_nodelist = compiled_parent.nodelist
+    # If the parent template has an ExtendsNode it is not the root.
+    for node in parent_nodelist:
+        # The ExtendsNode has to be the first non-text node.
+        if not isinstance(node, TextNode):
+            if isinstance(node, ExtendsNode):
+                return handle_extendsnode(node, context)
+            break
+    # Add blocks of the root template to block context.
+    blocks = dict((n.name, n) for n in parent_nodelist.get_nodes_by_type(BlockNode))
+    block_context.add_blocks(blocks)
+
+    block_stack = []
+    new_nodelist = remove_block_nodes(parent_nodelist, block_stack, block_context)
+    return new_nodelist
+
+
+def remove_block_nodes(nodelist, block_stack, block_context):
+    new_nodelist = NodeList()
+    for node in nodelist:
+        if isinstance(node, VariableNode):
+            var_name = node.filter_expression.token.strip()
+            if var_name == "block.super":
+                if not block_stack:
+                    continue
+                node = block_context.get_block(block_stack[-1].name)
+                if not node:
+                    continue
+        if isinstance(node, BlockNode):
+            expanded_block = expand_blocknode(node, block_stack, block_context)
+            new_nodelist.extend(expanded_block)
+        else:
+            # IfNode has nodelist as a @property so we can not modify it
+            if isinstance(node, IfNode):
+                node = copy(node)
+                for i, (condition, sub_nodelist) in enumerate(
+                    node.conditions_nodelists
+                ):
+                    sub_nodelist = remove_block_nodes(
+                        sub_nodelist, block_stack, block_context
+                    )
+                    node.conditions_nodelists[i] = (condition, sub_nodelist)
+            else:
+                for attr in node.child_nodelists:
+                    sub_nodelist = getattr(node, attr, None)
+                    if sub_nodelist:
+                        sub_nodelist = remove_block_nodes(
+                            sub_nodelist, block_stack, block_context
+                        )
+                        node = copy(node)
+                        setattr(node, attr, sub_nodelist)
+            new_nodelist.append(node)
+    return new_nodelist
+
+
+def expand_blocknode(node, block_stack, block_context):
+    popped_block = block = block_context.pop(node.name)
+    if block is None:
+        block = node
+    block_stack.append(block)
+    expanded_nodelist = remove_block_nodes(block.nodelist, block_stack, block_context)
+    block_stack.pop()
+    if popped_block is not None:
+        block_context.push(node.name, popped_block)
+    return expanded_nodelist
+

sendmail/parser.py

@@ -1,12 +1,13 @@
 import re
-
-from django.template import loader
+from django import template
+from django.template import loader, TemplateSyntaxError, TemplateDoesNotExist
 from django.template.base import Node, NodeList, VariableNode
 from django.template.context import Context
 from django.template.defaulttags import ForNode
+from django.template.loader import get_template
 from django.template.loader_tags import ExtendsNode, IncludeNode
 
-from compressor.offline.django import DjangoParser, handle_extendsnode
+from sendmail.django_compressor import handle_extendsnode
 
 
 def handle_includenode(includenode, context):
@@ -26,7 +27,19 @@ def handle_includenode(includenode, context):
     return included_template.template.nodelist
 
 
-class SendmailParser(DjangoParser):
+class SendmailParser:
+
+    def __init__(self, charset):
+        self.charset = charset
+
+    def parse(self, template_name):
+        try:
+            return get_template(template_name).template
+        except template.TemplateSyntaxError as e:
+            raise TemplateSyntaxError(str(e))
+        except template.TemplateDoesNotExist as e:
+            raise TemplateDoesNotExist(str(e))
+
     def get_nodelist(self, node, original, context=None):
         if isinstance(node, ExtendsNode):
             if context is None: