This policy lets you configure routing rules for the traffic in the mesh. It supports weighted routing and can be used to implement versioning across services or to support deployment strategies such as blue/green or canary.
Note the following:
The configuration must specify the data plane proxies for the routing rules.
The spec.destinations field supports only kuma.io/service.
All available tags are supported for spec.conf.
This is an outbound connection policy. Make sure that your data plane proxy configuration includes the appropriate tags.
The control plane creates a default TrafficRoute every time a new Mesh is created. The default TrafficRoute enables the traffic between all the services in the mesh.
apiVersion: kuma.io/v1alpha1
kind: TrafficRoute
mesh: default
metadata:name: full-example
spec:sources:-match:kuma.io/service: backend_default_svc_80
destinations:-match:kuma.io/service: redis_default_svc_6379
conf:http:-match:method:# one of either "prefix", "exact" or "regex" is allowedexact: GET
regex:"^POST|PUT$"path:# one of either "prefix", "exact" or "regex" is allowedprefix: /users
exact: /users/user-1regex:"^users$"headers:some-header:# one of either "prefix", "exact" or "regex" will be allowedexact: some-value
prefix: some-regex:"^users$"modify:# optional sectionpath:# one of "rewritePrefix" or "regex" is allowedrewritePrefix: /not-users # rewrites previously matched prefixregex:# (example to change the path from "/service/foo/v1/api" to "/v1/api/instance/foo")pattern:"^/service/([^/]+)(/.*)$"substitution:'\2/instance/\1'host:# one of "value" or "fromPath" is allowedvalue:"XYZ"fromPath:# (example to extract "envoyproxy.io" host header from "/envoyproxy.io/some/path" path)pattern:"^/(.+)/.+$"substitution:'\1'requestHeaders:add:-name: x-custom-header
value: xyz
append:true# if true then if there is x-custom-header already, it will append xyz to the value remove:-name: x-something
responseHeaders:add:-name: x-custom-header
value: xyz
append:trueremove:-name: x-something
destination:# one of "destination", "split" is allowedkuma.io/service: redis_default_svc_6379
split:-weight:100destination:kuma.io/service: redis_default_svc_6379
destination:# one of "destination", "split" is allowedkuma.io/service: redis_default_svc_6379
split:-weight:100destination:kuma.io/service: redis_default_svc_6379
loadBalancer:# one of "roundRobin", "leastRequest", "ringHash", "random", "maglev" is allowed roundRobin:{}leastRequest:choiceCount:8ringHash:hashFunction:"MURMUR_HASH_2"minRingSize:64maxRingSize:1024random:{}maglev:{}
type: TrafficRoute
name: full-example
mesh: default
sources:-match:kuma.io/service: backend
destinations:-match:kuma.io/service: redis
conf:http:-match:method:# one of either "prefix", "exact" or "regex" is allowedexact: GET
regex:"^POST|PUT$"path:# one of either "prefix", "exact" or "regex" is allowedprefix: /users
exact: /users/user-1regex:"^users$"headers:some-header:# one of either "prefix", "exact" or "regex" will be allowedexact: some-value
prefix: some-regex:"^users$"modify:# optional sectionpath:# one of "rewritePrefix" or "regex" is allowedrewritePrefix: /not-users # rewrites previously matched prefixregex:# (example to change the path from "/service/foo/v1/api" to "/v1/api/instance/foo")pattern:"^/service/([^/]+)(/.*)$"substitution:'\2/instance/\1'host:# one of "value" or "fromPath" is allowedvalue:"XYZ"fromPath:# (example to extract "envoyproxy.io" host header from "/envoyproxy.io/some/path" path)pattern:"^/(.+)/.+$"substitution:'\1'requestHeaders:add:-name: x-custom-header
value: xyz
append:true# if true then if there is x-custom-header already, it will append xyz to the value remove:-name: x-something
responseHeaders:add:-name: x-custom-header
value: xyz
append:trueremove:-name: x-something
destination:# one of "destination", "split" is allowedkuma.io/service: redis
split:-weight:100destination:kuma.io/service: redis
destination:# one of "destination", "split" is allowedkuma.io/service: redis
split:-weight:100destination:kuma.io/service: redis
loadBalancer:# one of "roundRobin", "leastRequest", "ringHash", "random", "maglev" is allowed roundRobin:{}leastRequest:choiceCount:8ringHash:hashFunction:"MURMUR_HASH_2"minRingSize:64maxRingSize:1024random:{}maglev:{}
Kuma utilizes positive weights in the TrafficRoute policy and not percentages, therefore Kuma does not check if the total adds up to 100. If we want to stop sending traffic to a destination service we change the weight for that service to 0.
We can use TrafficRoute to split a TCP traffic between services with different tags implementing A/B testing or canary deployments.
Here is an example of a TrafficRoute that splits the traffic over the two different versions of the application.
90% of the connections from backend_default_svc_80 service will be initiated to redis_default_svc_6379 with tag version: 1.0
and 10% of the connections will be initiated to version: 2.0
We can use TrafficRoute to fully reroute a TCP traffic to different version of a service or even completely different service.
Here is an example of a TrafficRoute that redirects the traffic to another-redis_default_svc_6379 when backend_default_svc_80 is trying to consume redis_default_svc_6379.
We can use TrafficRoute to split an HTTP traffic between services with different tags implementing A/B testing or canary deployments.
Here is an example of a TrafficRoute that splits the traffic from frontend_default_svc_80 to backend_default_svc_80 between versions,
but only on endpoints starting with /api. All other endpoints will go to version: 1.0
apiVersion: kuma.io/v1alpha1
kind: TrafficRoute
mesh: default
metadata:name: api-split
spec:sources:-match:kuma.io/service: frontend_default_svc_80
destinations:-match:kuma.io/service: backend_default_svc_80
conf:http:-match:path:prefix:"/api"split:-weight:90destination:kuma.io/service: backend_default_svc_80
version:'1.0'-weight:10destination:kuma.io/service: backend_default_svc_80
version:'2.0'destination:# default rule is applied when endpoint does not match any rules in http sectionkuma.io/service: backend_default_svc_80
version:'1.0'
type: TrafficRoute
name: api-split
mesh: default
sources:-match:kuma.io/service: frontend_default_svc_80
destinations:-match:kuma.io/service: backend_default_svc_80
conf:http:-match:path:prefix:"/api"split:-weight:90destination:kuma.io/service: backend_default_svc_80
version:'1.0'-weight:10destination:kuma.io/service: backend_default_svc_80
version:'2.0'destination:# default rule is applied when endpoint does not match any rules in http sectionkuma.io/service: backend_default_svc_80
version:'1.0'
We can use TrafficRoute to modify outgoing requests, by setting new path or changing request and response headers.
Here is an example of a TrafficRoute that redirect traffic to offers_default_svc_80 when frontend_default_svc_80 is trying to consume backend_default_svc_80 on /offers endpoint.
There are different load balancing algorithms that can be used to determine how traffic is routed to the destinations. By default TrafficRoute uses the roundRobin load balancer, but more options are available:
roundRobin is a simple algorithm in which each available upstream host is selected in round robin order.
Example:
loadBalancer:roundRobin:{}
1 2
leastRequest uses different algorithms depending on whether the hosts have the same or different weights. It has a single configuration field choiceCount, which denotes the number of random healthy hosts from which the host with the fewer active requests will be chosen.
Example:
loadBalancer:leastRequest:choiceCount:8
1 2 3
ringHash implements consistent hashing to the upstream hosts. It has the following fields:
hashFunction the hash function used to hash the hosts onto the ketama ring. Can be XX_HASH or MURMUR_HASH_2.