diff --git a/frappe/__init__.py b/frappe/__init__.py
index 95e74a1649..812c390494 100644
--- a/frappe/__init__.py
+++ b/frappe/__init__.py
@@ -502,16 +502,15 @@ def clear_cache(user=None, doctype=None):
 
 	:param user: If user is given, only user cache is cleared.
 	:param doctype: If doctype is given, only DocType cache is cleared."""
-	import frappe.sessions
+	import frappe.cache_manager
 	if doctype:
-		import frappe.model.meta
-		frappe.model.meta.clear_cache(doctype)
+		frappe.cache_manager.clear_doctype_cache(doctype)
 		reset_metadata_version()
 	elif user:
-		frappe.sessions.clear_cache(user)
+		frappe.cache_manager.clear_user_cache(user)
 	else: # everything
 		from frappe import translate
-		frappe.sessions.clear_cache()
+		frappe.cache_manager.clear_user_cache()
 		translate.clear_cache()
 		reset_metadata_version()
 		local.cache = {}
@@ -1489,7 +1488,7 @@ def safe_decode(param, encoding = 'utf-8'):
 	except Exception:
 		pass
 	return param
-	
+
 def parse_json(val):
 	from frappe.utils import parse_json
 	return parse_json(val)
@@ -1505,7 +1504,7 @@ def mock(type, size = 1, locale = 'en'):
 			results.append(data)
 
 	from frappe.chat.util import squashify
-		
+
 	results = squashify(results)
 
 	return results
\ No newline at end of file
diff --git a/frappe/cache_manager.py b/frappe/cache_manager.py
new file mode 100644
index 0000000000..63b5830598
--- /dev/null
+++ b/frappe/cache_manager.py
@@ -0,0 +1,77 @@
+# Copyright (c) 2018, Frappe Technologies Pvt. Ltd. and Contributors
+# MIT License. See license.txt
+
+from __future__ import unicode_literals
+
+import frappe
+import frappe.defaults
+from frappe.desk.notifications import delete_notification_count_for, clear_notifications
+
+common_default_keys = ["__default", "__global"]
+
+def clear_user_cache(user=None):
+	cache = frappe.cache()
+
+	groups = ("bootinfo", "user_recent", "roles", "user_doc", "lang",
+		"defaults", "user_permissions", "home_page", "linked_with",
+		"desktop_icons", 'portal_menu_items')
+
+	if user:
+		for name in groups:
+			cache.hdel(name, user)
+		cache.delete_keys("user:" + user)
+		clear_defaults_cache(user)
+	else:
+		for name in groups:
+			cache.delete_key(name)
+		clear_global_cache()
+		clear_defaults_cache()
+
+	clear_notifications(user)
+
+def clear_global_cache():
+	clear_doctype_cache()
+	frappe.cache().delete_value(["app_hooks", "installed_apps",
+		"app_modules", "module_app", "notification_config", 'system_settings',
+		'scheduler_events', 'time_zone', 'webhooks', 'active_domains', 'active_modules'])
+	frappe.setup_module_map()
+
+def clear_defaults_cache(user=None):
+	if user:
+		for p in ([user] + common_default_keys):
+			frappe.cache().hdel("defaults", p)
+	elif frappe.flags.in_install!="frappe":
+		frappe.cache().delete_key("defaults")
+
+def clear_doctype_cache(doctype=None):
+	cache = frappe.cache()
+
+	if getattr(frappe.local, 'meta_cache') and (doctype in frappe.local.meta_cache):
+		del frappe.local.meta_cache[doctype]
+
+	for key in ('is_table', 'doctype_modules'):
+		cache.delete_value(key)
+
+	groups = ["meta", "form_meta", "table_columns", "last_modified",
+		"linked_doctypes", 'email_alerts', 'workflow']
+
+	def clear_single(dt):
+		for name in groups:
+			cache.hdel(name, dt)
+
+	if doctype:
+		clear_single(doctype)
+
+		# clear all parent doctypes
+		for dt in frappe.db.sql("""select parent from tabDocField
+			where fieldtype="Table" and options=%s""", (doctype,)):
+			clear_single(dt[0])
+
+		# clear all notifications
+		delete_notification_count_for(doctype)
+
+	else:
+		# clear all
+		for name in groups:
+			cache.delete_value(name)
+
diff --git a/frappe/data_migration/doctype/data_migration_plan/data_migration_plan.py b/frappe/data_migration/doctype/data_migration_plan/data_migration_plan.py
index decd27f913..e85bb26b1a 100644
--- a/frappe/data_migration/doctype/data_migration_plan/data_migration_plan.py
+++ b/frappe/data_migration/doctype/data_migration_plan/data_migration_plan.py
@@ -10,7 +10,6 @@ from frappe.custom.doctype.custom_field.custom_field import create_custom_field
 from frappe.model.document import Document
 
 class DataMigrationPlan(Document):
-
 	def on_update(self):
 		# update custom fields in mappings
 		self.make_custom_fields_for_mappings()
diff --git a/frappe/defaults.py b/frappe/defaults.py
index 9fbc55a0d0..dec0706381 100644
--- a/frappe/defaults.py
+++ b/frappe/defaults.py
@@ -4,12 +4,11 @@
 from __future__ import unicode_literals
 import frappe
 from frappe.desk.notifications import clear_notifications
+from frappe.cache_manager import clear_defaults_cache, common_default_keys
 
 # Note: DefaultValue records are identified by parenttype
 # __default, __global or 'User Permission'
 
-common_keys = ["__default", "__global"]
-
 def set_user_default(key, value, user=None, parenttype=None):
 	set_default(key, value, user or frappe.session.user, parenttype)
 
@@ -154,10 +153,10 @@ def clear_default(key=None, value=None, parent=None, name=None, parenttype=None)
 			values.append(parenttype)
 
 	if parent:
-		clear_cache(parent)
+		clear_defaults_cache(parent)
 	else:
-		clear_cache("__default")
-		clear_cache("__global")
+		clear_defaults_cache("__default")
+		clear_defaults_cache("__global")
 
 	if not conditions:
 		raise Exception("[clear_default] No key specified.")
@@ -194,15 +193,8 @@ def get_defaults_for(parent="__default"):
 	return defaults
 
 def _clear_cache(parent):
-	if parent in common_keys:
+	if parent in common_default_keys:
 		frappe.clear_cache()
 	else:
 		clear_notifications(user=parent)
 		frappe.clear_cache(user=parent)
-
-def clear_cache(user=None):
-	if user:
-		for p in ([user] + common_keys):
-			frappe.cache().hdel("defaults", p)
-	elif frappe.flags.in_install!="frappe":
-		frappe.cache().delete_key("defaults")
diff --git a/frappe/desk/form/meta.py b/frappe/desk/form/meta.py
index 334ebec4da..256dca6991 100644
--- a/frappe/desk/form/meta.py
+++ b/frappe/desk/form/meta.py
@@ -7,7 +7,6 @@ from __future__ import unicode_literals
 import frappe, os
 from frappe.model.meta import Meta
 from frappe.modules import scrub, get_module_path, load_doctype_module
-from frappe.model.workflow import get_workflow_name
 from frappe.utils import get_html_format
 from frappe.translate import make_dict_from_messages, extract_messages_from_code
 from frappe.model.utils import render_include
@@ -143,7 +142,7 @@ class FormMeta(Meta):
 
 	def load_workflows(self):
 		# get active workflow
-		workflow_name = get_workflow_name(self.name)
+		workflow_name = self.get_workflow()
 		workflow_docs = []
 
 		if workflow_name and frappe.db.exists("Workflow", workflow_name):
diff --git a/frappe/model/document.py b/frappe/model/document.py
index 1f77b7e103..5b87633faa 100644
--- a/frappe/model/document.py
+++ b/frappe/model/document.py
@@ -13,6 +13,7 @@ from six import iteritems, string_types
 from werkzeug.exceptions import NotFound, Forbidden
 import hashlib, json
 from frappe.model import optional_fields
+from frappe.model.workflow import validate_workflow
 from frappe.utils.file_manager import save_url
 from frappe.utils.global_search import update_global_search
 from frappe.integrations.doctype.webhook import run_webhooks
@@ -443,6 +444,7 @@ class Document(BaseDocument):
 		self._extract_images_from_text_editor()
 		self._sanitize_content()
 		self._save_passwords()
+		self.validate_workflow()
 
 		children = self.get_all_children()
 		for d in children:
@@ -459,6 +461,11 @@ class Document(BaseDocument):
 			for fieldname in optional_fields:
 				self.set(fieldname, None)
 
+	def validate_workflow(self):
+		'''Validate if the workflow transition is valid'''
+		if self.meta.get_workflow():
+			validate_workflow(self)
+
 	def validate_set_only_once(self):
 		'''Validate that fields are not changed if not in insert'''
 		set_only_once_fields = self.meta.get_set_only_once_fields()
@@ -873,7 +880,8 @@ class Document(BaseDocument):
 		self._doc_before_save = None
 		if not (self.is_new()
 			and (getattr(self.meta, 'track_changes', False)
-				or self.meta.get_set_only_once_fields())):
+				or self.meta.get_set_only_once_fields()
+				or self.meta.get_workflow())):
 			self.get_doc_before_save()
 
 	def run_post_save_methods(self):
diff --git a/frappe/model/meta.py b/frappe/model/meta.py
index 1a78ed8569..b088822aec 100644
--- a/frappe/model/meta.py
+++ b/frappe/model/meta.py
@@ -24,6 +24,7 @@ from frappe.model.document import Document
 from frappe.model.base_document import BaseDocument
 from frappe.model.db_schema import type_map
 from frappe.modules import load_doctype_module
+from frappe.model.workflow import get_workflow_name
 from frappe import _
 
 def get_meta(doctype, cached=True):
@@ -238,6 +239,9 @@ class Meta(Document):
 		field = self.get_field(fieldname)
 		return field and field.translatable
 
+	def get_workflow(self):
+		return get_workflow_name(self.name)
+
 	def process(self):
 		# don't process for special doctypes
 		# prevent's circular dependency
@@ -510,36 +514,3 @@ def trim_tables(doctype=None):
 			query = """alter table `tab{doctype}` {columns}""".format(
 				doctype=doctype, columns=columns_to_remove)
 			frappe.db.sql_ddl(query)
-
-def clear_cache(doctype=None):
-	cache = frappe.cache()
-
-	if getattr(frappe.local, 'meta_cache') and (doctype in frappe.local.meta_cache):
-		del frappe.local.meta_cache[doctype]
-
-	for key in ('is_table', 'doctype_modules'):
-		cache.delete_value(key)
-
-	groups = ["meta", "form_meta", "table_columns", "last_modified",
-		"linked_doctypes", 'email_alerts']
-
-	def clear_single(dt):
-		for name in groups:
-			cache.hdel(name, dt)
-
-	if doctype:
-		clear_single(doctype)
-
-		# clear all parent doctypes
-		for dt in frappe.db.sql("""select parent from tabDocField
-			where fieldtype="Table" and options=%s""", (doctype,)):
-			clear_single(dt[0])
-
-		# clear all notifications
-		from frappe.desk.notifications import delete_notification_count_for
-		delete_notification_count_for(doctype)
-
-	else:
-		# clear all
-		for name in groups:
-			cache.delete_value(name)
diff --git a/frappe/model/sync.py b/frappe/model/sync.py
index 5b32b2a1b9..70752fb88b 100644
--- a/frappe/model/sync.py
+++ b/frappe/model/sync.py
@@ -74,7 +74,6 @@ def get_doc_files(files, start_path, force=0, sync_everything = False, verbose=F
 	for doctype in document_types:
 		doctype_path = os.path.join(start_path, doctype)
 		if os.path.exists(doctype_path):
-
 			for docname in os.listdir(doctype_path):
 				if os.path.isdir(os.path.join(doctype_path, docname)):
 					doc_path = os.path.join(doctype_path, docname, docname) + ".json"
diff --git a/frappe/model/workflow.py b/frappe/model/workflow.py
index dabc2822b4..6dbff7b6f8 100644
--- a/frappe/model/workflow.py
+++ b/frappe/model/workflow.py
@@ -3,24 +3,133 @@
 
 from __future__ import unicode_literals
 import frappe
+from frappe.utils import cint
+from frappe import _
+
+class WorkflowStateError(frappe.ValidationError): pass
+class WorkflowTransitionError(frappe.ValidationError): pass
+class WorkflowPermissionError(frappe.ValidationError): pass
 
 def get_workflow_name(doctype):
-	if getattr(frappe.local, "workflow_names", None) is None:
-		frappe.local.workflow_names = {}
-
-	if doctype not in frappe.local.workflow_names:
+	workflow_name = frappe.cache().hget('workflow', doctype)
+	if workflow_name is None:
 		workflow_name = frappe.db.get_value("Workflow", {"document_type": doctype,
 			"is_active": 1}, "name")
+		frappe.cache().hset('workflow', doctype, workflow_name or '')
 
-		frappe.local.workflow_names[doctype] = workflow_name
+	return workflow_name
 
-	return frappe.local.workflow_names[doctype]
+@frappe.whitelist()
+def get_transitions(doc, workflow = None):
+	'''Return list of possible transitions for the given doc'''
+	doc = frappe.get_doc(frappe.parse_json(doc))
 
-def get_default_state(doctype):
-	workflow_name = get_workflow_name(doctype)
-	return frappe.db.get_value("Workflow Document State", {"parent": workflow_name,
-		"idx":1}, "state")
+	if doc.is_new():
+		return []
 
-def get_state_fieldname(doctype):
-	workflow_name = get_workflow_name(doctype)
-	return frappe.db.get_value("Workflow", workflow_name, "workflow_state_field")
+	frappe.has_permission(doc, 'read', throw=True)
+	roles = frappe.get_roles()
+
+	if not workflow:
+		workflow = get_workflow(doc.doctype)
+	current_state = doc.get(workflow.workflow_state_field)
+
+	if not current_state:
+		frappe.throw(_('Workflow State not set'), WorkflowStateError)
+
+	transitions = []
+	for transition in workflow.transitions:
+		if transition.state == current_state and transition.allowed in roles:
+			if transition.condition:
+				# if condition, evaluate
+				# access to frappe.db.get_value and frappe.db.get_list
+				success = frappe.safe_eval(transition.condition,
+					dict(frappe = frappe._dict(
+						db = frappe._dict(get_value = frappe.db.get_value, get_list=frappe.db.get_list),
+						session = frappe.session
+					)),
+					dict(doc = doc))
+				if not success:
+					continue
+			transitions.append(transition.as_dict())
+
+	return transitions
+
+@frappe.whitelist()
+def apply_workflow(doc, action):
+	'''Allow workflow action on the current doc'''
+	doc = frappe.get_doc(frappe.parse_json(doc))
+	workflow = get_workflow(doc.doctype)
+	transitions = get_transitions(doc, workflow)
+
+	# find the transition
+	transition = None
+	for t in transitions:
+		if t.action == action:
+			transition = t
+
+	if not transition:
+		frappe.throw(_("Not a valid Workflow Action"), WorkflowTransitionError)
+
+	# update workflow state field
+	doc.set(workflow.workflow_state_field, transition.next_state)
+
+	# find settings for the next state
+	next_state = [d for d in workflow.states if d.state == transition.next_state][0]
+
+	# update any additional field
+	if next_state.update_field:
+		doc.set(next_state.update_field, next_state.update_value)
+
+	new_docstatus = cint(next_state.doc_status)
+	if doc.docstatus == 0 and new_docstatus == 0:
+		doc.save()
+	elif doc.docstatus == 0 and new_docstatus == 1:
+		doc.submit()
+	elif doc.docstatus == 1 and new_docstatus == 1:
+		doc.save()
+	elif doc.docstatus == 1 and new_docstatus == 2:
+		doc.cancel()
+	else:
+		frappe.throw(_('Illegal Document Status for {0}').format(next_state.state))
+
+	doc.add_comment('Workflow', _(next_state.state))
+
+	return doc
+
+def validate_workflow(doc):
+	'''Validate Workflow State and Transition for the current user.
+
+	- Check if user is allowed to edit in current state
+	- Check if user is allowed to transition to the next state (if changed)
+	'''
+	workflow = get_workflow(doc.doctype)
+
+	current_state = None
+	if getattr(doc, '_doc_before_save', None):
+		current_state = doc._doc_before_save.get(workflow.workflow_state_field)
+	next_state = doc.get(workflow.workflow_state_field)
+
+	if not next_state:
+		# set default state (maybe not set in insert)
+		current_state = next_state = workflow.states[0].state
+		doc.set(workflow.workflow_state_field, workflow.states[0].state)
+
+	state_row = [d for d in workflow.states if d.state == current_state]
+	if not state_row:
+		frappe.throw(_('{0} is not a valid Workflow State. Please update your Workflow and try again.'.format(frappe.bold(current_state))))
+	state_row = state_row[0]
+
+	# check if user is allowed to edit in current state
+	if not state_row.allow_edit in frappe.get_roles():
+		frappe.throw(_('Not allowed to edit in Workflow State {0}'.format(frappe.bold(current_state))), WorkflowPermissionError)
+
+	# if transitioning, check if user is allowed to transition
+	if current_state != next_state:
+		transitions = get_transitions(doc._doc_before_save)
+		transition = [d for d in transitions if d.next_state == next_state]
+		if not transition:
+			frappe.throw(_('Workflow State {0} is not allowed').format(frappe.bold(next_state)), WorkflowPermissionError)
+
+def get_workflow(doctype):
+	return frappe.get_doc('Workflow', get_workflow_name(doctype))
diff --git a/frappe/public/js/frappe/form/workflow.js b/frappe/public/js/frappe/form/workflow.js
index e3fde7ae84..4e428c0fae 100644
--- a/frappe/public/js/frappe/form/workflow.js
+++ b/frappe/public/js/frappe/form/workflow.js
@@ -26,22 +26,25 @@ frappe.ui.form.States = Class.extend({
 			var d = new frappe.ui.Dialog({
 				title: "Workflow: "
 					+ frappe.workflow.workflows[me.frm.doctype].name
-			})
-			var next_html = $.map(frappe.workflow.get_transitions(me.frm.doctype, state),
-				function(d) {
-					return d.action.bold() + __(" by Role ") + d.allowed;
-				}).join(", ") || __("None: End of Workflow").bold();
+			});
 
-			$(d.body).html("<p>"+__("Current status")+": " + state.bold() + "</p>"
-				+ "<p>"+__("Document is only editable by users of role")+": "
-					+ frappe.workflow.get_document_state(me.frm.doctype,
-						state).allow_edit.bold() + "</p>"
-				+ "<p>"+__("Next actions")+": "+ next_html +"</p>"
-				+ (me.frm.doc.__islocal ? ("<div class='alert alert-info'>"
-					+__("Workflow will start after saving.")+"</div>") : "")
-				+ "<p class='help'>"+__("Note: Other permission rules may also apply")+"</p>"
+			frappe.workflow.get_transitions(me.frm.doc).then((transitions) => {
+				var next_html = $.map(transitions,
+					function(d) {
+						return d.action.bold() + __(" by Role ") + d.allowed;
+					}).join(", ") || __("None: End of Workflow").bold();
+
+				$(d.body).html("<p>"+__("Current status")+": " + state.bold() + "</p>"
+					+ "<p>"+__("Document is only editable by users of role")+": "
+						+ frappe.workflow.get_document_state(me.frm.doctype,
+							state).allow_edit.bold() + "</p>"
+					+ "<p>"+__("Next actions")+": "+ next_html +"</p>"
+					+ (me.frm.doc.__islocal ? ("<div class='alert alert-info'>"
+						+__("Workflow will start after saving.")+"</div>") : "")
+					+ "<p class='help'>"+__("Note: Other permission rules may also apply")+"</p>"
 				).css({padding: '15px'});
-			d.show();
+				d.show();
+			});
 		}, true);
 	},
 
@@ -61,7 +64,7 @@ frappe.ui.form.States = Class.extend({
 		}
 	},
 
-	show_actions: function(state) {
+	show_actions: function() {
 		var added = false,
 			me = this;
 
@@ -72,57 +75,20 @@ frappe.ui.form.States = Class.extend({
 			return;
 		}
 
-		$.each(frappe.workflow.get_transitions(this.frm.doctype, state), function(i, d) {
-			if(frappe.user_roles.includes(d.allowed)) {
-				added = true;
-				me.frm.page.add_action_item(__(d.action), function() {
-					var action = d.action;
-					// capture current state
-					var doc_before_action = copy_dict(me.frm.doc);
-
-					// set new state
-					var next_state = frappe.workflow.get_next_state(me.frm.doctype,
-							me.frm.doc[me.state_fieldname], action);
-					me.frm.doc[me.state_fieldname] = next_state;
-					var new_state = frappe.workflow.get_document_state(me.frm.doctype, next_state);
-					var new_docstatus = cint(new_state.doc_status);
-
-
-					if(new_state.update_field) {
-						me.frm.set_value(new_state.update_field, new_state.update_value);
-					}
-
-					// revert state on error
-					var on_error = function() {
-						// reset in locals
-						frappe.model.add_to_locals(doc_before_action);
-						me.frm.refresh();
-					}
-
-					// success - add a comment
-					var success = function() {
-						me.frm.timeline.insert_comment("Workflow", next_state);
-					}
-					if(new_docstatus==1 && me.frm.doc.docstatus==0) {
-						me.frm.savesubmit(null, success, on_error);
-					} else if(new_docstatus==0 && me.frm.doc.docstatus==0) {
-						me.frm.save("Save", success, null, on_error);
-					} else if(new_docstatus==1 && me.frm.doc.docstatus==1) {
-						me.frm.save("Update", success, null, on_error);
-					} else if(new_docstatus==2 && me.frm.doc.docstatus==1) {
-						me.frm.savecancel(null, success, on_error);
-					} else {
-						frappe.msgprint(__("Document Status transition from ") + me.frm.doc.docstatus + " "
-							+ __("to") +
-							new_docstatus + " " + __("is not allowed."));
-						frappe.msgprint(__("Document Status transition from {0} to {1} is not allowed", [me.frm.doc.docstatus, new_docstatus]));
-						return false;
-					}
-
-					return false;
-
-				});
-			}
+		frappe.workflow.get_transitions(this.frm.doc).then(transitions => {
+			$.each(transitions, function(i, d) {
+				if(frappe.user_roles.includes(d.allowed)) {
+					added = true;
+					me.frm.page.add_action_item(__(d.action), function() {
+						frappe.xcall('frappe.model.workflow.apply_workflow',
+							{doc: me.frm.doc, action: d.action})
+							.then((doc) => {
+								frappe.model.sync(doc);
+								me.frm.refresh();
+							});
+					});
+				}
+			});
 		});
 
 		if(added) {
@@ -144,11 +110,5 @@ frappe.ui.form.States = Class.extend({
 			this.set_default_state();
 		}
 		return this.frm.doc[this.state_fieldname];
-	},
-
-	bind_action: function() {
-		var me = this;
-		this.dropdown.on("click", "[data-action]", function() {
-		})
 	}
 });
diff --git a/frappe/public/js/frappe/model/workflow.js b/frappe/public/js/frappe/model/workflow.js
index fcbf1931a3..4a22e9c387 100644
--- a/frappe/public/js/frappe/model/workflow.js
+++ b/frappe/public/js/frappe/model/workflow.js
@@ -32,18 +32,14 @@ frappe.workflow = {
 		});
 		return value;
 	},
-	get_transitions: function(doctype, state) {
-		frappe.workflow.setup(doctype);
-		return frappe.get_children(frappe.workflow.workflows[doctype], "transitions", {state:state});
+	get_transitions: function(doc) {
+		frappe.workflow.setup(doc.doctype);
+		return frappe.xcall('frappe.model.workflow.get_transitions', {doc: doc});
 	},
 	get_document_state: function(doctype, state) {
 		frappe.workflow.setup(doctype);
 		return frappe.get_children(frappe.workflow.workflows[doctype], "states", {state:state})[0];
 	},
-	get_next_state: function(doctype, state, action) {
-		return frappe.get_children(frappe.workflow.workflows[doctype], "transitions", {
-			state:state, action:action})[0].next_state;
-	},
 	is_read_only: function(doctype, name) {
 		var state_fieldname = frappe.workflow.get_state_fieldname(doctype);
 		if(state_fieldname) {
diff --git a/frappe/public/js/frappe/request.js b/frappe/public/js/frappe/request.js
index 76158e69e8..1a8adf7bbd 100644
--- a/frappe/public/js/frappe/request.js
+++ b/frappe/public/js/frappe/request.js
@@ -8,6 +8,21 @@ frappe.request.url = '/';
 frappe.request.ajax_count = 0;
 frappe.request.waiting_for_ajax = [];
 
+frappe.xcall = function(method, params) {
+	return new Promise((resolve, reject) => {
+		frappe.call({
+			method: method,
+			args: params,
+			callback: (r) => {
+				resolve(r.message);
+			},
+			error: (r) => {
+				reject(r.message);
+			}
+		});
+	});
+};
+
 // generic server call (call page, object)
 frappe.call = function(opts) {
 	if (!frappe.is_online()) {
diff --git a/frappe/sessions.py b/frappe/sessions.py
index 5b10d5a819..150b7c6444 100644
--- a/frappe/sessions.py
+++ b/frappe/sessions.py
@@ -18,45 +18,17 @@ import frappe.translate
 from frappe.utils.change_log import get_change_log
 import redis
 from six.moves.urllib.parse import unquote
-from frappe.desk.notifications import clear_notifications
 from six import text_type
+from frappe.cache_manager import clear_global_cache, clear_user_cache
 
 @frappe.whitelist()
 def clear(user=None):
 	frappe.local.session_obj.update(force=True)
 	frappe.local.db.commit()
-	clear_cache(frappe.session.user)
+	clear_user_cache(frappe.session.user)
 	clear_global_cache()
 	frappe.response['message'] = _("Cache Cleared")
 
-def clear_cache(user=None):
-	cache = frappe.cache()
-
-	groups = ("bootinfo", "user_recent", "roles", "user_doc", "lang",
-		"defaults", "user_permissions", "home_page", "linked_with",
-		"desktop_icons", 'portal_menu_items')
-
-	if user:
-		for name in groups:
-			cache.hdel(name, user)
-		cache.delete_keys("user:" + user)
-		frappe.defaults.clear_cache(user)
-	else:
-		for name in groups:
-			cache.delete_key(name)
-		clear_global_cache()
-		frappe.defaults.clear_cache()
-
-	clear_notifications(user)
-
-def clear_global_cache():
-	frappe.model.meta.clear_cache()
-	frappe.cache().delete_value(["app_hooks", "installed_apps",
-		"app_modules", "module_app", "notification_config", 'system_settings',
-		'scheduler_events', 'time_zone', 'webhooks', 'active_domains', 'active_modules'])
-	frappe.setup_module_map()
-
-
 def clear_sessions(user=None, keep_current=False, device=None, force=False):
 	'''Clear other sessions of the current user. Called at login / logout
 
diff --git a/frappe/tests/test_permissions.py b/frappe/tests/test_permissions.py
index 3402f60aba..eb442b60fa 100644
--- a/frappe/tests/test_permissions.py
+++ b/frappe/tests/test_permissions.py
@@ -209,7 +209,7 @@ class TestPermissions(unittest.TestCase):
 
 		frappe.set_user("test2@example.com")
 
-		frappe.model.meta.clear_cache("Blog Post")
+		frappe.clear_cache(doctype="Blog Post")
 
 		doc = frappe.get_doc("Blog Post", "-test-blog-post")
 		self.assertFalse(doc.has_permission("read"))
@@ -217,7 +217,7 @@ class TestPermissions(unittest.TestCase):
 		doc = frappe.get_doc("Blog Post", "-test-blog-post-2")
 		self.assertTrue(doc.has_permission("read"))
 
-		frappe.model.meta.clear_cache("Blog Post")
+		frappe.clear_cache(doctype="Blog Post")
 
 	def if_owner_setup(self):
 		update('Blog Post', 'Blogger', 0, 'if_owner', 1)
@@ -227,7 +227,7 @@ class TestPermissions(unittest.TestCase):
 		add_user_permission("Blogger", "_Test Blogger 1",
 			"test2@example.com")
 
-		frappe.model.meta.clear_cache("Blog Post")
+		frappe.clear_cache(doctype="Blog Post")
 
 	def test_insert_if_owner_with_user_permissions(self):
 		"""If `If Owner` is checked for a Role, check if that document
diff --git a/frappe/utils/scheduler.py b/frappe/utils/scheduler.py
index fce586a97e..d688c1406a 100755
--- a/frappe/utils/scheduler.py
+++ b/frappe/utils/scheduler.py
@@ -76,6 +76,11 @@ def enqueue_events_for_all_sites():
 			print(frappe.get_traceback())
 
 def enqueue_events_for_site(site, queued_jobs):
+	def log_and_raise():
+		frappe.logger(__name__).error('Exception in Enqueue Events for Site {0}'.format(site) +
+			'\n' + frappe.get_traceback())
+		raise # pylint: disable=misplaced-bare-raise
+
 	try:
 		frappe.init(site=site)
 		if frappe.local.conf.maintenance_mode:
@@ -91,11 +96,13 @@ def enqueue_events_for_site(site, queued_jobs):
 		enqueue_events(site=site, queued_jobs=queued_jobs)
 
 		frappe.logger(__name__).debug('Queued events for site {0}'.format(site))
-
+	except pymysql.OperationalError as e:
+		if e.args[0]==ER.ACCESS_DENIED_ERROR:
+			frappe.logger(__name__).debug('Access denied for site {0}'.format(site))
+		else:
+			log_and_raise()
 	except:
-		frappe.logger(__name__).error('Exception in Enqueue Events for Site {0}'.format(site) +
-			'\n' + frappe.get_traceback())
-		raise
+		log_and_raise()
 
 	finally:
 		frappe.destroy()
diff --git a/frappe/website/doctype/portal_settings/portal_settings.py b/frappe/website/doctype/portal_settings/portal_settings.py
index 72fc175930..5c1cee20fb 100644
--- a/frappe/website/doctype/portal_settings/portal_settings.py
+++ b/frappe/website/doctype/portal_settings/portal_settings.py
@@ -42,8 +42,7 @@ class PortalSettings(Document):
 	def clear_cache(self):
 		# make js and css
 		# clear web cache (for menus!)
-		from frappe.sessions import clear_cache
-		clear_cache('Guest')
+		frappe.clear_cache(user='Guest')
 
 		from frappe.website.render import clear_cache
 		clear_cache()
diff --git a/frappe/website/doctype/website_script/website_script.py b/frappe/website/doctype/website_script/website_script.py
index d1cf631f41..5648c27fd6 100644
--- a/frappe/website/doctype/website_script/website_script.py
+++ b/frappe/website/doctype/website_script/website_script.py
@@ -9,11 +9,10 @@ import frappe
 from frappe.model.document import Document
 
 class WebsiteScript(Document):
-		
+
 	def on_update(self):
 		"""clear cache"""
-		from frappe.sessions import clear_cache
-		clear_cache('Guest')
+		frappe.clear_cache(user = 'Guest')
 
 		from frappe.website.render import clear_cache
 		clear_cache()
\ No newline at end of file
diff --git a/frappe/website/doctype/website_settings/website_settings.py b/frappe/website/doctype/website_settings/website_settings.py
index 3c50f3edc9..2f3e38c872 100644
--- a/frappe/website/doctype/website_settings/website_settings.py
+++ b/frappe/website/doctype/website_settings/website_settings.py
@@ -59,8 +59,7 @@ class WebsiteSettings(Document):
 	def clear_cache(self):
 		# make js and css
 		# clear web cache (for menus!)
-		from frappe.sessions import clear_cache
-		clear_cache('Guest')
+		frappe.clear_cache(user = 'Guest')
 
 		from frappe.website.render import clear_cache
 		clear_cache()
diff --git a/frappe/workflow/doctype/workflow/test_workflow.py b/frappe/workflow/doctype/workflow/test_workflow.py
index 3b866b8e40..f3af853bec 100644
--- a/frappe/workflow/doctype/workflow/test_workflow.py
+++ b/frappe/workflow/doctype/workflow/test_workflow.py
@@ -4,8 +4,92 @@ from __future__ import unicode_literals
 
 import frappe
 import unittest
-
-test_records = frappe.get_test_records('Workflow')
+from frappe.utils import random_string
+from frappe.model.workflow import apply_workflow, WorkflowTransitionError, WorkflowPermissionError
 
 class TestWorkflow(unittest.TestCase):
-	pass
+	def setUp(self):
+		if not getattr(self, 'workflow', None):
+			frappe.get_doc(dict(doctype='Role',
+				role_name='Test Approver')).insert(ignore_if_duplicate=True)
+
+			if frappe.db.exists('Workflow', 'Test ToDo'):
+				self.workflow = frappe.get_doc('Workflow', 'Test ToDo')
+				self.workflow.save()
+			else:
+				self.workflow = frappe.new_doc('Workflow')
+				self.workflow.workflow_name = 'Test ToDo'
+				self.workflow.document_type = 'ToDo'
+				self.workflow.workflow_state_field = 'workflow_state'
+				self.workflow.is_active = 1
+				self.workflow.append('states', dict(
+					state = 'Pending', allow_edit = 'All'
+				))
+				self.workflow.append('states', dict(
+					state = 'Approved', allow_edit = 'Test Approver',
+					update_field = 'status', update_value = 'Closed'
+				))
+				self.workflow.append('states', dict(
+					state = 'Rejected', allow_edit = 'Test Approver'
+				))
+				self.workflow.append('transitions', dict(
+					state = 'Pending', action='Approve', next_state = 'Approved', allowed='Test Approver'
+				))
+				self.workflow.append('transitions', dict(
+					state = 'Pending', action='Reject', next_state = 'Rejected', allowed='Test Approver'
+				))
+				self.workflow.append('transitions', dict(
+					state = 'Rejected', action='Review', next_state = 'Pending', allowed='All'
+				))
+				self.workflow.insert()
+
+		frappe.set_user('Administrator')
+
+	def test_default_condition(self):
+		'''test default condition is set'''
+		todo = frappe.get_doc(dict(doctype='ToDo', description='workflow ' + random_string(10))).insert()
+
+		# default condition is set
+		self.assertEqual(todo.workflow_state, 'Pending')
+
+		return todo
+
+	def test_approve(self):
+		'''test simple workflow'''
+		todo = self.test_default_condition()
+
+		apply_workflow(todo, 'Approve')
+
+		# default condition is set
+		self.assertEqual(todo.workflow_state, 'Approved')
+		self.assertEqual(todo.status, 'Closed')
+
+		return todo
+
+	def test_wrong_action(self):
+		'''Check illegal action (approve after reject)'''
+		todo = self.test_approve()
+
+		self.assertRaises(WorkflowTransitionError, apply_workflow, todo, 'Reject')
+
+	def test_workflow_role(self):
+		'''Check if user is allowed to edit in state via role'''
+		todo = self.test_approve()
+
+		todo.description = 'new'
+
+		frappe.set_user('test@example.com')
+		self.assertRaises(WorkflowPermissionError, todo.save, ignore_permissions=True)
+		frappe.set_user('Administrator')
+
+	def test_workflow_condition(self):
+		'''Test condition in transition'''
+		self.workflow.transitions[0].condition = 'doc.status == "Closed"'
+		self.workflow.save()
+
+		# only approve if status is closed
+		self.assertRaises(WorkflowTransitionError, self.test_approve)
+
+		self.workflow.transitions[0].condition = ''
+		self.workflow.save()
+
diff --git a/frappe/workflow/doctype/workflow/workflow.py b/frappe/workflow/doctype/workflow/workflow.py
index 9de175c168..c00dcf6616 100644
--- a/frappe/workflow/doctype/workflow/workflow.py
+++ b/frappe/workflow/doctype/workflow/workflow.py
@@ -8,7 +8,6 @@ from frappe import _
 from frappe.model.document import Document
 
 class Workflow(Document):
-
 	def validate(self):
 		self.set_active()
 		self.create_custom_field_for_workflow_state()
diff --git a/frappe/workflow/doctype/workflow_transition/workflow_transition.json b/frappe/workflow/doctype/workflow_transition/workflow_transition.json
index 7df6700569..835ac29c8d 100644
--- a/frappe/workflow/doctype/workflow_transition/workflow_transition.json
+++ b/frappe/workflow/doctype/workflow_transition/workflow_transition.json
@@ -1,142 +1,293 @@
 {
- "allow_copy": 0, 
- "allow_import": 0, 
- "allow_rename": 0, 
- "beta": 0, 
- "creation": "2013-02-22 01:27:36", 
- "custom": 0, 
- "description": "Defines actions on states and the next step and allowed roles.", 
- "docstatus": 0, 
- "doctype": "DocType", 
- "editable_grid": 1, 
+ "allow_copy": 0,
+ "allow_guest_to_view": 0,
+ "allow_import": 0,
+ "allow_rename": 0,
+ "beta": 0,
+ "creation": "2013-02-22 01:27:36",
+ "custom": 0,
+ "description": "Defines actions on states and the next step and allowed roles.",
+ "docstatus": 0,
+ "doctype": "DocType",
+ "editable_grid": 1,
  "fields": [
   {
-   "allow_on_submit": 0, 
-   "bold": 0, 
-   "collapsible": 0, 
-   "fieldname": "state", 
-   "fieldtype": "Link", 
-   "hidden": 0, 
-   "ignore_user_permissions": 0, 
-   "ignore_xss_filter": 0, 
-   "in_filter": 0, 
-   "in_list_view": 1, 
-   "label": "State", 
-   "length": 0, 
-   "no_copy": 0, 
-   "options": "Workflow State", 
-   "permlevel": 0, 
-   "print_hide": 0, 
-   "print_hide_if_no_value": 0, 
-   "print_width": "200px", 
-   "read_only": 0, 
-   "report_hide": 0, 
-   "reqd": 1, 
-   "search_index": 0, 
-   "set_only_once": 0, 
-   "unique": 0, 
+   "allow_bulk_edit": 0,
+   "allow_on_submit": 0,
+   "bold": 0,
+   "collapsible": 0,
+   "columns": 0,
+   "fieldname": "state",
+   "fieldtype": "Link",
+   "hidden": 0,
+   "ignore_user_permissions": 0,
+   "ignore_xss_filter": 0,
+   "in_filter": 0,
+   "in_global_search": 0,
+   "in_list_view": 1,
+   "in_standard_filter": 0,
+   "label": "State",
+   "length": 0,
+   "no_copy": 0,
+   "options": "Workflow State",
+   "permlevel": 0,
+   "print_hide": 0,
+   "print_hide_if_no_value": 0,
+   "print_width": "200px",
+   "read_only": 0,
+   "remember_last_selected_value": 0,
+   "report_hide": 0,
+   "reqd": 1,
+   "search_index": 0,
+   "set_only_once": 0,
+   "translatable": 0,
+   "unique": 0,
    "width": "200px"
-  }, 
+  },
   {
-   "allow_on_submit": 0, 
-   "bold": 0, 
-   "collapsible": 0, 
-   "fieldname": "action", 
-   "fieldtype": "Link", 
-   "hidden": 0, 
-   "ignore_user_permissions": 0, 
-   "ignore_xss_filter": 0, 
-   "in_filter": 0, 
-   "in_list_view": 1, 
-   "label": "Action", 
-   "length": 0, 
-   "no_copy": 0, 
-   "options": "Workflow Action", 
-   "permlevel": 0, 
-   "print_hide": 0, 
-   "print_hide_if_no_value": 0, 
-   "print_width": "200px", 
-   "read_only": 0, 
-   "report_hide": 0, 
-   "reqd": 1, 
-   "search_index": 0, 
-   "set_only_once": 0, 
-   "unique": 0, 
+   "allow_bulk_edit": 0,
+   "allow_on_submit": 0,
+   "bold": 0,
+   "collapsible": 0,
+   "columns": 0,
+   "fieldname": "action",
+   "fieldtype": "Link",
+   "hidden": 0,
+   "ignore_user_permissions": 0,
+   "ignore_xss_filter": 0,
+   "in_filter": 0,
+   "in_global_search": 0,
+   "in_list_view": 1,
+   "in_standard_filter": 0,
+   "label": "Action",
+   "length": 0,
+   "no_copy": 0,
+   "options": "Workflow Action",
+   "permlevel": 0,
+   "print_hide": 0,
+   "print_hide_if_no_value": 0,
+   "print_width": "200px",
+   "read_only": 0,
+   "remember_last_selected_value": 0,
+   "report_hide": 0,
+   "reqd": 1,
+   "search_index": 0,
+   "set_only_once": 0,
+   "translatable": 0,
+   "unique": 0,
    "width": "200px"
-  }, 
+  },
   {
-   "allow_on_submit": 0, 
-   "bold": 0, 
-   "collapsible": 0, 
-   "fieldname": "next_state", 
-   "fieldtype": "Link", 
-   "hidden": 0, 
-   "ignore_user_permissions": 0, 
-   "ignore_xss_filter": 0, 
-   "in_filter": 0, 
-   "in_list_view": 1, 
-   "label": "Next State", 
-   "length": 0, 
-   "no_copy": 0, 
-   "options": "Workflow State", 
-   "permlevel": 0, 
-   "print_hide": 0, 
-   "print_hide_if_no_value": 0, 
-   "print_width": "200px", 
-   "read_only": 0, 
-   "report_hide": 0, 
-   "reqd": 1, 
-   "search_index": 0, 
-   "set_only_once": 0, 
-   "unique": 0, 
+   "allow_bulk_edit": 0,
+   "allow_on_submit": 0,
+   "bold": 0,
+   "collapsible": 0,
+   "columns": 0,
+   "fieldname": "next_state",
+   "fieldtype": "Link",
+   "hidden": 0,
+   "ignore_user_permissions": 0,
+   "ignore_xss_filter": 0,
+   "in_filter": 0,
+   "in_global_search": 0,
+   "in_list_view": 1,
+   "in_standard_filter": 0,
+   "label": "Next State",
+   "length": 0,
+   "no_copy": 0,
+   "options": "Workflow State",
+   "permlevel": 0,
+   "print_hide": 0,
+   "print_hide_if_no_value": 0,
+   "print_width": "200px",
+   "read_only": 0,
+   "remember_last_selected_value": 0,
+   "report_hide": 0,
+   "reqd": 1,
+   "search_index": 0,
+   "set_only_once": 0,
+   "translatable": 0,
+   "unique": 0,
    "width": "200px"
-  }, 
+  },
   {
-   "allow_on_submit": 0, 
-   "bold": 0, 
-   "collapsible": 0, 
-   "fieldname": "allowed", 
-   "fieldtype": "Link", 
-   "hidden": 0, 
-   "ignore_user_permissions": 0, 
-   "ignore_xss_filter": 0, 
-   "in_filter": 0, 
-   "in_list_view": 1, 
-   "label": "Allowed", 
-   "length": 0, 
-   "no_copy": 0, 
-   "options": "Role", 
-   "permlevel": 0, 
-   "print_hide": 0, 
-   "print_hide_if_no_value": 0, 
-   "print_width": "200px", 
-   "read_only": 0, 
-   "report_hide": 0, 
-   "reqd": 1, 
-   "search_index": 0, 
-   "set_only_once": 0, 
-   "unique": 0, 
+   "allow_bulk_edit": 0,
+   "allow_on_submit": 0,
+   "bold": 0,
+   "collapsible": 0,
+   "columns": 0,
+   "fieldname": "allowed",
+   "fieldtype": "Link",
+   "hidden": 0,
+   "ignore_user_permissions": 0,
+   "ignore_xss_filter": 0,
+   "in_filter": 0,
+   "in_global_search": 0,
+   "in_list_view": 1,
+   "in_standard_filter": 0,
+   "label": "Allowed",
+   "length": 0,
+   "no_copy": 0,
+   "options": "Role",
+   "permlevel": 0,
+   "print_hide": 0,
+   "print_hide_if_no_value": 0,
+   "print_width": "200px",
+   "read_only": 0,
+   "remember_last_selected_value": 0,
+   "report_hide": 0,
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