PD HTTP API self-protection

[nolouch]

Feature Request

Describe your feature request related problem

PD is the most important metadata service center of the cluster, and it also includes TSO services. PD needs to have certain self-protection capabilities, among which, we need to limit the access rate of some heavy APIs. here, we focus HTTP API first.

Describe the feature you'd like

Consider add middleware, use ratelimiter to limit the rate of the HeavyAPIs request, such as /hotspot/regions/history

Teachability, Documentation, Adoption, Migration Strategy

• middleware

[nolouch]

/assign @qidi1

[ti-chi-bot]

@nolouch: GitHub didn't allow me to assign the following users: qidi1.

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In response to this:

/assign @qidi1

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[rleungx]

/assign @CabinfeverB

[ti-chi-bot]

@rleungx: GitHub didn't allow me to assign the following users: CabinfeverB.

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In response to this:

/assign @CabinfeverB

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[CabinfeverB]

/assign

[CabinfeverB]

refer #4480, Closed since most tasks has been finished.