client.go

package client

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"net/http"

	"code.fbi.h-da.de/danet/quant/goKMS/config"
	"code.fbi.h-da.de/danet/quant/goKMS/kms/crypto"
	kmstls "code.fbi.h-da.de/danet/quant/goKMS/kms/tls"
	"github.com/sirupsen/logrus"
)

type CkmsAkmsClient struct {
	url        string
	httpClient *http.Client
}

func NewCkmsAkmsClient(url string, tlsConfig config.TLSConfig) (*CkmsAkmsClient, error) {
	client := &http.Client{}

	if tlsConfig.Active {
		tlsConf, err := kmstls.GenerateTLSLibraryConfig(tlsConfig)
		if err != nil {
			return nil, fmt.Errorf("unable to generate TLS config: %w", err)
		}

		client.Transport = &http.Transport{
			TLSClientConfig: tlsConf,
		}
	}

	return &CkmsAkmsClient{
		url:        url,
		httpClient: client,
	}, nil
}

type PushKSAKeyRequest struct {
	RequestID string          `json:"request_ID"`
	ProcessID string          `json:"process_ID"`
	KSAKeys   []crypto.KSAKey `json:"ksa_keys"`
}

func (c *CkmsAkmsClient) SendKSAKeysToRequestingInstances(requestID string, processID string, ksaKeys []crypto.KSAKey) error {
	pushRequest := PushKSAKeyRequest{
		RequestID: requestID,
		ProcessID: processID,
		KSAKeys:   ksaKeys,
	}

	jsonData, err := json.Marshal(pushRequest)
	if err != nil {
		logrus.Errorf("Error marshaling JSON: %s", err)
		return err
	}

	// TODO: also log the response body if request failed
	resp, err := c.httpClient.Post(c.url, "application/json", bytes.NewBuffer(jsonData))
	if err != nil {
		body, err2 := io.ReadAll(resp.Body)
		if err2 != nil {
			logrus.Errorf("Error reading POST response body: %s", err2)
		}
		logrus.Errorf("Error sending POST request: %s, received response body: %s", err, string(body))
		logrus.Errorf("Tried to send request: %s to url: %s", jsonData, c.url)
		return err
	}
	err = resp.Body.Close()
	if err != nil {
		logrus.Errorf("Error closing response body: %s", err)
	}

	if resp.StatusCode != http.StatusNoContent {
		logrus.Errorf("Unexpected response status code: %d", resp.StatusCode)
		logrus.Errorf("Tried to send request: %s to url: %s", jsonData, c.url)
		return err
	}

	logrus.Infof("Successfully sent request: %s to url: %s", jsonData, c.url)
	return nil
}