From 3ee3572cdc802c194d5ea5ead49de6a1c3ef4a02 Mon Sep 17 00:00:00 2001
From: Tobias Wochinger <t.wochinger@rasa.com>
Date: Tue, 6 Oct 2020 14:16:28 +0200
Subject: [PATCH] change default session timeout from 0 to 60 minutes

This enables sessions by default.
---
 changelog/6934.removal.md     | 12 ++++++++++++
 docs/docs/migration-guide.mdx | 12 ++++++++++++
 rasa/shared/constants.py      |  2 +-
 rasa/shared/core/domain.py    |  2 --
 4 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100644 changelog/6934.removal.md

diff --git a/changelog/6934.removal.md b/changelog/6934.removal.md
new file mode 100644
index 000000000000..b52ac10a36c8
--- /dev/null
+++ b/changelog/6934.removal.md
@@ -0,0 +1,12 @@
+[Conversation sessions](domain.mdx#session-configuration) are now enabled by default
+if your [Domain](domain.mdx) does not contain a session configuration.
+Previously a missing session configuration was treated as if conversation sessions
+were disabled. You can explicitly disable conversation sessions using the following 
+snippet:
+
+```yaml-rasa title="domain.yml"
+session_config:
+  # A session expiration time of `0`
+  # disables conversation sessions
+  session_expiration_time: 0
+```
\ No newline at end of file
diff --git a/docs/docs/migration-guide.mdx b/docs/docs/migration-guide.mdx
index 8cb1ae9e8444..1b1395f87ee6 100644
--- a/docs/docs/migration-guide.mdx
+++ b/docs/docs/migration-guide.mdx
@@ -29,6 +29,18 @@ how you can migrate from one version to another.
   component in your `policies` configuration (`config.yml`) you can replace it
   with `TEDPolicy`. It accepts the same configuration parameters.
 
+* [Conversation sessions](domain.mdx#session-configuration) are now enabled by default
+  if your [Domain](domain.mdx) does not contain a session configuration. Previously a
+  missing session configuration was treated as if conversation sessions were disabled.
+  You can explicitly disable conversation sessions using the following snippet:
+
+  ```yaml-rasa title="domain.yml"
+  session_config:
+    # A session expiration time of `0`
+    # disables conversation sessions
+    session_expiration_time: 0
+  ```
+
 ### Training data files
 
 You can convert existing NLU, Stories, and NLG (i.e. `responses.md`) training data
diff --git a/rasa/shared/constants.py b/rasa/shared/constants.py
index 20eda5a9b647..9ef8fad715bb 100644
--- a/rasa/shared/constants.py
+++ b/rasa/shared/constants.py
@@ -32,7 +32,7 @@
 
 DOMAIN_SCHEMA_FILE = "utils/schemas/domain.yml"
 
-DEFAULT_SESSION_EXPIRATION_TIME_IN_MINUTES = 0
+DEFAULT_SESSION_EXPIRATION_TIME_IN_MINUTES = 60
 DEFAULT_CARRY_OVER_SLOTS_TO_NEW_SESSION = True
 
 DEFAULT_NLU_FALLBACK_INTENT_NAME = "nlu_fallback"
diff --git a/rasa/shared/core/domain.py b/rasa/shared/core/domain.py
index cd6dccfcb560..5b2ce8b0cfbd 100644
--- a/rasa/shared/core/domain.py
+++ b/rasa/shared/core/domain.py
@@ -86,7 +86,6 @@ class SessionConfig(NamedTuple):
 
     @staticmethod
     def default() -> "SessionConfig":
-        # TODO: 2.0, reconsider how to apply sessions to old projects
         return SessionConfig(
             rasa.shared.constants.DEFAULT_SESSION_EXPIRATION_TIME_IN_MINUTES,
             rasa.shared.constants.DEFAULT_CARRY_OVER_SLOTS_TO_NEW_SESSION,
@@ -185,7 +184,6 @@ def from_dict(cls, data: Dict) -> "Domain":
     def _get_session_config(session_config: Dict) -> SessionConfig:
         session_expiration_time_min = session_config.get(SESSION_EXPIRATION_TIME_KEY)
 
-        # TODO: 2.0 reconsider how to apply sessions to old projects and legacy trackers
         if session_expiration_time_min is None:
             session_expiration_time_min = (
                 rasa.shared.constants.DEFAULT_SESSION_EXPIRATION_TIME_IN_MINUTES