about config entry topic

[h9ing]

HI, I want to know more about entry topic.

OPAL server OPAL_DATA_CONFIG_SOURCES was setting like this:
{"config": {"entries": [{"url": "http://10.31.98.154:8080/v1/opal/policyData1", "topics": ["policy_data_1"]}, {"url": "http://10.31.98.154:8080/v1/opal/policyData2", "topics": ["policy_data_2"]}]}}

OPAL client OPAL_DATA_TOPICS was setting like this:
policy_data_1

OPAL server log:

OPAL client log:

notify to OPAL server topic update request

I gave OPAL server a update request, and put topic "policy_data_1" & "policy_data_2" to difference entry.
I expected to see OPAL client which subscribed topic "policy_data_1" would only fetch topic "policy_data_1" data, but it got both "policy_data_1" and "policy_data_2" data.

question:

1. When OPAL client start and get config, it will fetch all data in entries, but will not subscribe the topic which in entries. Just like this answer, right?

2. Ｗhy OPAL client only subscribed topic "policy_data_1" data, but it still received topic "policy_data_2" update notification and got topic "policy_data_2" data?
   So if I want to notify 2 client which subscribe difference topic, I can't put 2 topic update info in the same request?

Thank you!

[orweis]

Hi @h9ing , I skimmed through this to be honest - Bu t I think you're just missing the dst_path so the values would be written in different keys in OPA.

@asafc - please correct me if I'm wrong

[h9ing]

Hi @orweis,
I am afraid there is a misunderstanding.

My question is when I notified policy data update (topic "policy_data_1" & "policy_data_2" in difference entry), OPAL client which only subscribed topic "policy_data_1" would also fetched topic "policy_data_2" data.

I think the “dst_path” should only affects the policy data path in OPA cache. And it is ok to put my policy data in default path "/" in my case.
Get started with OPAL docker containers - Step 5: Server config - data sources

And I tried to set “dst_path”, but OPAL client which only subscribed topic "policy_data_1" still fetched topic "policy_data_2" data.

OPAL server OPAL_DATA_CONFIG_SOURCES was setting like this:
{"config": {"entries": [{"url": "http://10.31.98.154:8080/v1/opal/policyData1", "topics": ["policy_data_1"], "dst_path": "policyData1"}, {"url": "http://10.31.98.154:8080/v1/opal/policyData2", "topics": ["policy_data_2"], "dst_path": "policyData2"}]}}

OPAL client OPAL_DATA_TOPICS was setting like this:
policy_data_1

OPAL server log:

OPAL client log:

notify to OPAL server topic update request:

I think OPAL server combine 2 difference entry.
2022-07-14T01:54:40.197563+0000 | opal_server.data.data_update_publisher | INFO | [8] Publishing data update to topics: ['policy_data_1', 'policy_data_2'], reason: test, entries: [('http://10.31.98.154:8080/v1/opal/policyData1', 'PUT', 'policyData1'), ('http://10.31.98.154:8080/v1/opal/policyData2', 'PUT', 'policyData2')]
And if any OPAL client subscribed one of topics, even in difference entry, it will fetch all topic data.

Is this normal?

Thanks you!

[asafc]

Hi @h9ing,

This indeed seems to be a bug in OPAL server.

• You are submitting a data update events that contains multiple topics.
• OPAL server seems to replicated that DataUpdate object to all topics.
• OPAL client correctly only gets the message on the policy_data_1 topic, but the message contains entries that do not belong to that topic.

I will open an issue and we will fix the bug.

In the meanwhile i suggest to publish multiple DataUpdate events, each one only with one topic, and with entries that much that topic inside.

[h9ing]

Hi @asafc

That's right !

I will update my code and use loop to notify OPAL server about policy data update.

Thanks for helping me and look forward to the new release. 😀