improve synapse redis socket mounting

group_vars/matrix_servers

@@ -4846,10 +4846,12 @@ matrix_synapse_redis_password: "{{ valkey_connection_password if valkey_enabled
 
 # unix socket connection, disabled by default temporarily until properly tested
 matrix_synapse_redis_path_enabled: false
-# path to the Redis socket inside the Synapse container, using Synapse's default value
-matrix_synapse_redis_path: "{{ '/tmp/redis.sock' if valkey_enabled else '' }}"
+# path to the Redis socket's parent dir inside the Synapse container
+matrix_synapse_redis_path: "{{ '/tmp/valkey' if valkey_enabled else '' }}"
+# redis socket filename
+matrix_synapse_redis_path_socket: "{{ '/valkey.sock' if valkey_enabled else '' }}"
 # path to the Redis socket on the host, using Valkey
-matrix_synapse_redis_path_host: "{{ valkey_run_path+'/valkey.sock' if valkey_enabled else '' }}"
+matrix_synapse_redis_path_host: "{{ valkey_run_path if valkey_enabled else '' }}"
 
 matrix_synapse_container_extra_arguments_auto: "{{ matrix_homeserver_container_extra_arguments_auto }}"
 matrix_synapse_app_service_config_files_auto: "{{ matrix_homeserver_app_service_config_files_auto }}"

roles/custom/matrix-synapse/defaults/main.yml

@@ -1250,9 +1250,11 @@ matrix_synapse_redis_port: 6379
 # Connection option 2: Unix socket (takes precedence over TCP if `matrix_synapse_redis_path` is set)
 # disabled by default
 matrix_synapse_redis_path_enabled: false
-# the path to the redis socket inside the container, Synapse default's is "/tmp/redis.sock"
-matrix_synapse_redis_path: ""
-# the path to the redis socket on the host, e.g., "/matrix/valkey/run/valkey.sock"
+# the path to the redis socket's parent dir (/tmp, not /tmp/redis.sock file) inside the container, Synapse default's is "/tmp/redis.sock"
+matrix_synapse_redis_path: "/tmp"
+# the filename of the redis socket, inside the container, Synapse default's is "redis.sock"
+matrix_synapse_redis_path_socket: "/redis.sock"
+# the path to the redis socket on the host, e.g., "/matrix/valkey/run" (parent dir, not the socket file itself).
 matrix_synapse_redis_path_host: ""
 
 # Controls whether Synapse starts a replication listener necessary for workers.

roles/custom/matrix-synapse/templates/synapse/homeserver.yaml.j2

@@ -2934,7 +2934,7 @@ redis:
 
   # The full path to a local Unix socket file. If this is used, host and port are ignored.
   {% if matrix_synapse_redis_path_enabled %}
-  path: {{ matrix_synapse_redis_path | to_json }}
+  path: {{ (matrix_synapse_redis_path + matrix_synapse_redis_path_socket) | to_json }}
   {% endif %}
 
   # Optional database ID to connect to. Defaults to 0.