APACHE APISIX supports Consul as a service discovery
First of all, we need to add following configuration in conf/config.yaml
:
discovery: consul: servers: # make sure service name is unique in these consul servers - "http://127.0.0.1:8500" # `http://127.0.0.1:8500` and `http://127.0.0.1:8600` are different clusters - "http://127.0.0.1:8600" # `consul` service is default skip service token: "..." # if your consul cluster has enabled acl access control, you need to specify the token skip_services: # if you need to skip special services - "service_a" timeout: connect: 1000 # default 2000 ms read: 1000 # default 2000 ms wait: 60 # default 60 sec weight: 1 # default 1 fetch_interval: 5 # default 3 sec, only take effect for keepalive: false way keepalive: true # default true, use the long pull way to query consul servers sort_type: "origin" # default origin default_service: # you can define default service when missing hit host: "127.0.0.1" port: 20999 metadata: fail_timeout: 1 # default 1 ms weight: 1 # default 1 max_fails: 1 # default 1 dump: # if you need, when registered nodes updated can dump into file path: "logs/consul.dump" expire: 2592000 # unit sec, here is 30 day
And you can config it in short by default value:
discovery: consul: servers: - "http://127.0.0.1:8500"
The keepalive
has two optional values:
true
, default and recommend value, use the long pull way to query consul serversfalse
, not recommend, it would use the short pull way to query consul servers, then you can set the fetch_interval
for fetch intervalThe sort_type
has four optional values:
origin
, not sortinghost_sort
, sort by hostport_sort
, sort by portcombine_sort
, with the precondition that hosts are ordered, ports are also ordered.When we need reload apisix
online, as the consul
module maybe loads data from CONSUL slower than load routes from ETCD, and would get the log at the moment before load successfully from consul:
http_access_phase(): failed to set upstream: no valid upstream node
So, we import the dump
function for consul
module. When reload, would load the dump file before from consul; when the registered nodes in consul been updated, would dump the upstream nodes into file automatically.
The dump
has three optional values now:
path
, the dump file save pathlogs/consul.dump
/tmp/consul.dump
apisix
has the dump file's read-write access permission,eg: add below config in conf/config.yaml
nginx_config: # config for render the template to generate nginx.conf user: root # specifies the execution user of the worker process.
load_on_init
, default value is true
true
, just try to load the data from the dump file before loading data from consul when starting, does not care the dump file exists or notfalse
, ignore loading data from the dump filetrue
or false
, we don't need to prepare a dump file for apisix at anytimeexpire
, unit sec, avoiding load expired dump data when load0
, it is unexpired foreverNow, register nodes into consul:
curl -X PUT 'http://127.0.0.1:8500/v1/agent/service/register' \ -d '{ "ID": "service_a1", "Name": "service_a", "Tags": ["primary", "v1"], "Address": "127.0.0.1", "Port": 8000, "Meta": { "service_a_version": "4.0" }, "EnableTagOverride": false, "Weights": { "Passing": 10, "Warning": 1 } }' curl -X PUT 'http://127.0.0.1:8500/v1/agent/service/register' \ -d '{ "ID": "service_a1", "Name": "service_a", "Tags": ["primary", "v1"], "Address": "127.0.0.1", "Port": 8002, "Meta": { "service_a_version": "4.0" }, "EnableTagOverride": false, "Weights": { "Passing": 10, "Warning": 1 } }'
In some cases, same service name might exist in different consul servers. To avoid confusion, use the full consul key url path as service name in practice.
Here is an example of routing a request with a URL of “/*” to a service which named “service_a” and use consul discovery client in the registry :
:::note You can fetch the admin_key
from config.yaml
and save to an environment variable with the following command:
admin_key=$(yq '.deployment.admin.admin_key[0].key' conf/config.yaml | sed 's/"//g')
:::
$ curl http://127.0.0.1:9180/apisix/admin/routes/1 -H "X-API-KEY: $admin_key" -X PUT -i -d ' { "uri": "/*", "upstream": { "service_name": "service_a", "type": "roundrobin", "discovery_type": "consul" } }'
The format response as below:
{ "key": "/apisix/routes/1", "value": { "uri": "/*", "priority": 0, "id": "1", "upstream": { "scheme": "http", "type": "roundrobin", "hash_on": "vars", "discovery_type": "consul", "service_name": "service_a", "pass_host": "pass" }, "create_time": 1669267329, "status": 1, "update_time": 1669267329 } }
You could find more usage in the apisix/t/discovery/consul.t
file.
Consul service discovery also supports use in L4, the configuration method is similar to L7.
$ curl http://127.0.0.1:9180/apisix/admin/stream_routes/1 -H "X-API-KEY: $admin_key" -X PUT -i -d ' { "remote_addr": "127.0.0.1", "upstream": { "scheme": "tcp", "service_name": "service_a", "type": "roundrobin", "discovery_type": "consul" } }'
You could find more usage in the apisix/t/discovery/stream/consul.t
file.
It also offers control api for debugging.
GET /v1/discovery/consul/dump
For example:
# curl http://127.0.0.1:9090/v1/discovery/consul/dump | jq { "config": { "fetch_interval": 3, "timeout": { "wait": 60, "connect": 6000, "read": 6000 }, "weight": 1, "servers": [ "http://172.19.5.30:8500", "http://172.19.5.31:8500" ], "keepalive": true, "default_service": { "host": "172.19.5.11", "port": 8899, "metadata": { "fail_timeout": 1, "weight": 1, "max_fails": 1 } }, "skip_services": [ "service_d" ] }, "services": { "service_a": [ { "host": "127.0.0.1", "port": 30513, "weight": 1 }, { "host": "127.0.0.1", "port": 30514, "weight": 1 } ], "service_b": [ { "host": "172.19.5.51", "port": 50051, "weight": 1 } ], "service_c": [ { "host": "127.0.0.1", "port": 30511, "weight": 1 }, { "host": "127.0.0.1", "port": 30512, "weight": 1 } ] } }
It offers another control api for dump file view now. Maybe would add more api for debugging in future.
GET /v1/discovery/consul/show_dump_file
For example:
curl http://127.0.0.1:9090/v1/discovery/consul/show_dump_file | jq { "services": { "service_a": [ { "host": "172.19.5.12", "port": 8000, "weight": 120 }, { "host": "172.19.5.13", "port": 8000, "weight": 120 } ] }, "expire": 0, "last_update": 1615877468 }