disable opencensus

[zirain]

follow envoyproxy/envoy#33912, need remove all related things from istio?

cc @kyessenov @lei-tang

[kyessenov]

I'd prefer if we just kept it in Google builds. We don't expect much help from OSS Istio here, and it's not worth exposing the entire project to the mess of opencensus deprecation.

[zirain]

is it fine to remove directly? better to deprecated in 1.23 and removed in 1.24?

[kyessenov]

@lei-tang @zirain There are several usages of opencensus that need different solutions:

1. The test that @zirain disabled is for zipkin. We need to stop using opencensus for zipkin tracing.
2. OpenCensus tracing driver needs to be removed from OSS Istio. It's only used for Google tracing integration.
3. OpenCensus metrics driver needs to be removed from OSS Istio Proxy. It's only used for Google monitoring integration and resides in Istio/proxy.

[lei-tang]

With regard to OpenCensus removal from OSS Istio, the following items need to be done.

In the OSS istio proxy repository, the usage of following items need to be removed:

• OpenCensus tracer
• Metrics implemented through the OpenCensus SDK.

In the OSS istio repository, the code programming the OpenCensus tracer into xDS should be removed.

The user guides referring to the items above should be updated.

[howardjohn]

@lei-tang @kyessenov which of these (if any) will we be doing as well?

1. Removing Istiod OC XDS generation
2. Removing Istiod SD XDS generation
3. Removing istio/proxy SD filter

[kyessenov]

@howardjohn I'm doing (3).

[howardjohn]

Does that mean we should do 1+2 as well? Doesn't have to be you specifically. I would assume (2) at least

[kyessenov]

@howardjohn I don't think we strictly have to remove protobuf generation. Envoy policy, for example, is to keep protobufs from deleted filters because it's disruptive to delete Protos.

[howardjohn]

I suppose we want to do it for 1 release so we have N-1 support, why do we need it longer though?

[lei-tang]

Istio Stackdriver metrics are implemented using the OpenCensus SDK. I will create a PR to remove the XDS programming of the Istio Stackdriver metrics from Istio.

[lei-tang]

I am working on a PR #51070 to remove the XDS programming of the Istio Stackdriver logs from Istio.

[lei-tang]

#51078: remove OpenCensus tracer from Istio XDS.

[craigbox]

(/cc self to make sure documentation is updated to remove mention of OpenCensus and Stackdriver.)