[DISPATCH-1254] qdstat sometimes raises "TypeError: 'NoneType' object is not iterable"

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.2.0
• Fix Version/s: 1.6.0
• Component/s: Routing Engine
• Assignee: Ganesh Murthy
• Reporter: Alan Conway
• Created: 23/Jan/19 15:41
• Updated: 28/Mar/19 17:22
• Resolved: 25/Jan/19 14:22

Description

Calling qdstat -nv repeatedly to check the status of a router network sometimes raises a "nonetype not iterable error.

Reproducer: 

make install this version of quiver (extented to allow separate send/receive URLS). If you have maven installed you should edit the makefile to disable the Java arrow as the build is very slow and fragile:

    https://github.com/alanconway/quiver

run the attached script like this:

    qdr-chain.sh quiver --arrow c  --count 1000 --send-url //:10001/x //:10001/x     

The script generates config files, starts four routers, waits for qdstat -nv to show the full topology and then runs quiver as directed. Edit the script to change logging or other config settings. Log and config files are created in the current directory.

WARNING the script will kill any running qdrouterd.

While waiting for the router network to stabilize I see output like the following. The initial connection error is expected as the router has not yet started, but the TypeError in the middle is unexpected.

 

{{ConnectionException: Connection amqp://localhost:10001/$management disconnected: Condition('proton:io', 'recv: errno: 111') }}
{{waiting... }}
{{Routers in the Network }}
{{ router-id next-hop link ver cost neighbors valid-origins }}
{{ ================================================================ }}
{{ 1 (self) - 1 [] [] }}
{{waiting... }}
{{Routers in the Network }}
{{ router-id next-hop link ver cost neighbors valid-origins }}
{{ ================================================================ }}
{{ 1 (self) - 1 [] [] }}
{{waiting... }}
{{Routers in the Network }}
{{ router-id next-hop link ver cost neighbors valid-origins }}
{{ ================================================================ }}
{{ 1 (self) - 1 [] [] }}
{{waiting... }}
{{TypeError: 'NoneType' object is not iterable }}
{{waiting... }}
{{Routers in the Network }}
{{Last Topology Change: Wednesday Jan 23 15:40:34 2019 GMT }}
{{ router-id next-hop link ver cost neighbors valid-origins }}
{{ ================================================================= }}
{{ 1 (self) - 1 ['2'] [] }}
{{ 2 - 0 1 1 ['1', '3'] [] }}
{{ 3 2 - 2 [] [] }}
{{waiting... }}
{{Routers in the Network }}
{{Last Topology Change: Wednesday Jan 23 15:40:39 2019 GMT }}
{{ router-id next-hop link ver cost neighbors valid-origins }}
{{ ================================================================= }}
{{ 1 (self) - 1 ['2'] [] }}
{{ 2 - 0 1 1 ['1', '3'] [] }}
{{ 3 2 - 1 2 ['2', '4'] [] }}
{{ 4 2 - 1 3 ['3'] [] }}

Issue Links

• is a clone of: DISPATCH-1249 Rejected messages in a 4-router chain
• links to: GitHub Pull Request #444