Dynamic Rule Configuration

All the rules can be queried or modified in memory and these modifications take effects immediately. Sentinel also provides APIs for you to define your own rules.

Rule definitions

There are 3 kinds of rules: flow rules, degradation rules, and system rules.

1.Flow Rules

Flow Rule has the following fields：

Field	Description	Default value
resource	resource name
count	thredshold
grade	depends on QPS or concurrency(active thread count)	QPS
limitApp	whether to count on callers	no
strategy	count on the resource itself, or on the related resource(refResource)，or on entry resource(refResource)	resource itself
controlBehavior	how to act after block criteria are met. To block immediately, or wait in a queue, or slow warm up	block immediatley

Multiple rules can be applied to one resource.

2.Degradation Rules Degrade has the following fields：

Field	Description	Default value
resource	resource name
count	thredshold
grade	down grade o RT or qps	RT
timeWindow	timewindow when degradation happens

3. System Protection Rules

Query active rules

Run the following command to query current active rules：

curl http://localhost:8719/getRules?type=? ,type=flow

If the type is flow, it will return all flow rules in JSON format; if the type is degrade, it will return all degradation rules in JSON format; and if the type is system, it will return system rules.

Modify rules

You can modify the following rules via the following command：

curl http://localhost:8719/setRules?type=<XXXX>&data=<DATA>

Data is the rules in JSON format.

Customize your persistent rules

All the rules' configuration above are stored in memory, which means that rules will be lost if the application restart. We can implement DataSource to define persist rule logic.

1. Via Nacos. You can refer to [TODO] for the sample file.
2. Via SQL, Git, You can refer to [TODO] for the sample file.
3. Via Dashboard, You can refer to [TODO] for the sample file.
4. Via File