Krakend HTTP Cache

A cached http client for the KrakenD framework tested on krakend-ce 1.4.1

Using it

This package exposes two simple factories capable to create a instances of the proxy.HTTPClientFactory and the proxy.BackendFactory interfaces, respectively, embedding an in-memory-cached http client using the package github.com/gregjones/httpcache. The client will cache the responses honoring the defined Cache HTTP header.

import 	(
	"context"
	"net/http"
	"github.com/luraproject/lura/config"
	"github.com/luraproject/lura/proxy"
	"github.com/devopsfaith/krakend-httpcache"
)

requestExecutorFactory := func(cfg *config.Backend) proxy.HTTPRequestExecutor {
	clientFactory := httpcache.NewHTTPClient(cfg)
	return func(ctx context.Context, req *http.Request) (*http.Response, error) {
		return clientFactory(ctx).Do(req.WithContext(ctx))
	}
}

You can create your own proxy.HTTPRequestExecutor and inject it into your BackendFactory

Lean changes

Modified added support to redis & redis-cluster as cache backends.

Backend extra configuration block example with default values:

"backend": [
{
    "extra_config": {
        "github.com/devopsfaith/krakend-httpcache": {
            "type": "redis",
            "redis": {
                "mode": "redis",
                "address": "localhost:6379",
                "dialTimeout": "100ms",
                "readTimeout": "100ms",
                "writeTimeout": "200ms",
                "maxRetries": 0,
                "idleTimeout": "5m",
                "idleCheckFrequency": "1m",
                "poolSize": 10,
                "poolTimeout": "10ms",
                "ttl": "1h",
            }
        },
    }
}

Config options:

• type (optional, if missing memory will be used for an inmemory cache): memory | redis

redis block is required if type is set to redis:

• mode (required): redis or rediscluster
• address (required): Address to the redis node or one of the redis nodes when using a cluster. Format: ip:port
• ttl: TTL to be used on all redis keys being set. Redis will expire the keys after this time. This value is independent from the Cache-Control header that the library will use to decide if the cached value is still valid or not.

Check the description of the following options in the go-redis package documentation: https://github.com/go-redis/redis

• dialTimeout:
• readTimeout:
• writeTimeout:
• maxRetries:
• idleTimeout:
• idleCheckFrequency:
• poolSize:
• poolTimeout:

How to build into krakend

We need to recompile kraken-cd in order to interpret new redis config schema

Edit krakend-ce go.mod file and in the requires section add

require (
    github.com/leandroreox/krakend-rediscache v1.0
)

And at the end of the go.mod file add a replace sentence

replace github.com/devopsfaith/krakend-httpcache v1.4.0 => github.com/leandroreox/krakend-rediscache v1.0

re-build krakend-ce, and run it !