Add registry_client_timeout parameter

Add a "registry_client_timeout" parameter which specifies the
time, in seconds, that an API server will wait for a registry
request to complete.

This prevents API clients hanging indefinitely in the event
that the registry becomes unresponsive.

Addresses LP bug 1089391.

Change-Id: Ib27b6eecdcb65cbe644c156a0ca5cd0d0b4638dd

doc/source/configuring.rst

@@ -235,6 +235,14 @@ When using SSL in connections to the registry server, do not require
 validation via a certifying authority. This is the registry's equivalent of
 specifying --insecure on the command line using glanceclient for the API
 
+* ``registry_client_timeout=SECONDS``
+
+Optional. Default: ``600``.
+
+The period of time, in seconds, that the API server will wait for a registry
+request to complete. A value of '0' implies no timeout.
+
+
 Configuring Logging in Glance
 -----------------------------
 

etc/glance-api.conf

@@ -137,6 +137,11 @@ registry_client_protocol = http
 # Default: False
 #registry_client_insecure = False
 
+# The period of time, in seconds, that the API server will wait for a registry
+# request to complete. A value of '0' implies no timeout.
+# Default: 600
+#registry_client_timeout = 600
+
 # ============ Notification System Options =====================
 
 # Notifications can be sent when images are create, updated or deleted.

glance/common/client.py

@@ -197,6 +197,9 @@ class BaseClient(object):
         self.host = host
         self.port = port or self.DEFAULT_PORT
         self.timeout = timeout
+        # A value of '0' implies never timeout
+        if timeout == 0:
+            self.timeout = None
         self.use_ssl = use_ssl
         self.auth_tok = auth_tok
         self.creds = creds or {}

glance/registry/__init__.py

@@ -38,6 +38,7 @@ registry_client_opts = [
     cfg.StrOpt('registry_client_cert_file'),
     cfg.StrOpt('registry_client_ca_file'),
     cfg.BoolOpt('registry_client_insecure', default=False),
+    cfg.IntOpt('registry_client_timeout', default=600),
     cfg.StrOpt('metadata_encryption_key', secret=True),
 ]
 registry_client_ctx_opts = [
@@ -87,6 +88,7 @@ def configure_registry_client():
         'cert_file': CONF.registry_client_cert_file,
         'ca_file': CONF.registry_client_ca_file,
         'insecure': CONF.registry_client_insecure,
+        'timeout': CONF.registry_client_timeout,
     }