kinvolk/test-odcds

demo of Envoy lazy config loading

Test ODCDS

A dummy ODCDS server for Envoy.

Flow

1. A client sends an HTTP request to Envoy. Envoy doesn't know about the target cluster.
2. Envoy queries the ODCDS server for the cluster configuration using xDS.
3. The ODCDS server returns the cluster configuration.
4. Envoy sends an HTTP request to the cluster.
5. The cluster responds.
6. Envoy sends a response to the client.

Subsequent HTTP requests from the client don't trigger new xDS queries as long as the TTL of the cluster resource doesn't expire and Envoy isn't restarted.

Running

NOTE: We need 4 shells for experimenting with the server.

Run the ODCDS server in shell #1:

go run .

Run the dummy cluster in shell #2:

go run ./dummycluster

Run Envoy in shell #3:

# Configure the path to the Envoy binary.
export ENVOY_BIN=/tmp/envoy-bin/envoy

# Run Envoy.
$ENVOY_BIN --config-path examples/envoy.yaml

Send a request through Envoy in shell #4:

curl -H "Cluster-Name: foo" localhost:8080

test-odcds's Issues

Which version of Envoy to use

Description

When I try the example configuration with an Envoy docker image with version 53867ab5cc97c945f8c7f6a771d28443b1bcec43/1.23.0-dev/Clean/RELEASE/BoringSSL, I get the following error message when starting Envoy:

[critical][main] [source/server/server.cc:117] error initializing configuration '/envoy-custom.yaml': Protobuf message (type envoy.config.bootstrap.v3.Bootstrap reason INVALID_ARGUMENT:odcds_config: Cannot find field.) has unknown fields

Impact

Envoy does not start, hence the test does not work.

Environment and steps to reproduce

Start Envoy with the configuration yaml from the example directory.

Expected behaviour

Envoy to startup successfully and start querying the xDS cluster to obtain the cluster configuration(s).

Additional information

None