quota

API Rate / Quota Limiter Middleware

This package provides a simple and minimalist implementation of API rate / quota request limiter within a http middleware.

How To Use

1. Implement APIQuotaInterface in your package

   type APIQuotaInterface interface {
       // Parse token from http request.
       ParseTokenFromRequest(ctx context.Context, r *http.Request) (string, error)
       // Check current token's quota plan.
       GetTokenQuotaPlan(ctx context.Context, token string) (int64, error)
   }
   

2. Initiate package (as singleton)

   type APIQuotaOption struct {
       KeyPrefix string
       Cache     *redis.Pool
       Logger    *logrus.Logger
       Interface APIQuotaInterface
   }
   
   // Call this once.
   quota.Init(APIQuotaOption{
       KeyPrefix: "foo",
       Cache:     cachePool,
       Logger:    logrus.New(),
       Interface: customAPIQuotaImplementation{}, // Use struct defined from 1st step.
   })
   

NOTE

• Ideally GetTokenQuotaPlan is implemented by selecting into a database.
• Expiration / validity of the API token should be managed yourself (i.e. create custom cron to set / expire tokens).

Example

Example can be found in the test file: quota_test.go.