remove the metadata foo

Signed-off-by: Miek Gieben <miek@miek.nl>
This commit is contained in:
Miek Gieben
2020-01-23 16:49:47 +01:00
parent 7ffd0b57ac
commit 93eaaf3bad

View File

@@ -103,27 +103,18 @@ How are clients match against the data we receive from xDS endpoint? Ignoring `l
it will go through the following steps:
1. Does the cluster exist? If not return NXDOMAIN, otherwise continue.
2. Check the cluster's metadata, if available and set to DRAINING, return a NODATA response,
otherwise continue.
3. Run through the endpoints, discard any endpoints that are not HEALTHY. If we are left with no
2. Run through the endpoints, discard any endpoints that are not HEALTHY. If we are left with no
endpoint return a NODATA response, otherwise continue.
4. If weights are assigned use those to pick an endpoint, otherwise randomly pick one and return a
3. If weights are assigned use those to pick an endpoint, otherwise randomly pick one and return a
response to the client.
If `locality` *has* been specified there is an extra step between 3 and 4.
If `locality` *has* been specified there is an extra step between 2 and 3.
3a. Match the endpoints using the locality that groups several of them, it's the most specific match
2a. Match the endpoints using the locality that groups several of them, it's the most specific match
from left to right in the `locality` list; if no **REGION,ZONE,SUBZONE** matches then try
**REGION,ZONE** and then **REGION**. If still not match, move on the to next one. If we found
none, we continue with step 4 above, ignoring any locality.
### Metadata
The metadata must be populated as follows (remains to be seen if this is the way to do it). There
must be a field with the key `HEALTH_STATUS` and the string value must be `DRAINING`. These values
are copied from Envoy protocol buffers. Anything other than `DRAINING` and `HEALTH_STATUS` or a
missing metadata means *traffic* will ignore it.
## Metrics
If monitoring is enabled (via the *prometheus* plugin) then the following metric are exported: