contentserver/server/handlerequest.go

117 lines
3.4 KiB
Go

package server
import (
"fmt"
"time"
"github.com/foomo/contentserver/log"
"github.com/foomo/contentserver/repo"
"github.com/foomo/contentserver/requests"
"github.com/foomo/contentserver/responses"
"github.com/foomo/contentserver/status"
jsoniter "github.com/json-iterator/go"
"github.com/prometheus/client_golang/prometheus"
)
var json = jsoniter.ConfigCompatibleWithStandardLibrary
func handleRequest(r *repo.Repo, handler Handler, jsonBytes []byte, metrics *status.Metrics) (replyBytes []byte, err error) {
var (
reply interface{}
apiErr error
jsonErr error
start = time.Now()
processIfJSONIsOk = func(err error, processingFunc func()) {
if err != nil {
jsonErr = err
return
}
processingFunc()
}
)
// handle and process
switch handler {
case HandlerGetURIs:
getURIRequest := &requests.URIs{}
processIfJSONIsOk(json.Unmarshal(jsonBytes, &getURIRequest), func() {
reply = r.GetURIs(getURIRequest.Dimension, getURIRequest.IDs)
})
addMetrics(metrics, HandlerGetURIs, start, jsonErr, apiErr)
case HandlerGetContent:
contentRequest := &requests.Content{}
processIfJSONIsOk(json.Unmarshal(jsonBytes, &contentRequest), func() {
reply, apiErr = r.GetContent(contentRequest)
})
addMetrics(metrics, HandlerGetContent, start, jsonErr, apiErr)
case HandlerGetNodes:
nodesRequest := &requests.Nodes{}
processIfJSONIsOk(json.Unmarshal(jsonBytes, &nodesRequest), func() {
reply = r.GetNodes(nodesRequest)
})
addMetrics(metrics, HandlerGetNodes, start, jsonErr, apiErr)
case HandlerUpdate:
updateRequest := &requests.Update{}
processIfJSONIsOk(json.Unmarshal(jsonBytes, &updateRequest), func() {
reply = r.Update()
})
addMetrics(metrics, HandlerUpdate, start, jsonErr, apiErr)
case HandlerGetRepo:
repoRequest := &requests.Repo{}
processIfJSONIsOk(json.Unmarshal(jsonBytes, &repoRequest), func() {
reply = r.GetRepo()
})
addMetrics(metrics, HandlerGetRepo, start, jsonErr, apiErr)
default:
reply = responses.NewError(1, "unknown handler: "+string(handler))
addMetrics(metrics, "default", start, jsonErr, apiErr)
}
// error handling
if jsonErr != nil {
log.Error(" could not read incoming json:", jsonErr)
reply = responses.NewError(2, "could not read incoming json "+jsonErr.Error())
} else if apiErr != nil {
log.Error(" an API error occured:", apiErr)
reply = responses.NewError(3, "internal error "+apiErr.Error())
}
return encodeReply(reply)
}
func addMetrics(metrics *status.Metrics, handlerName Handler, start time.Time, errJSON error, errAPI error) {
var (
duration = time.Since(start)
s = "succeeded"
)
if errJSON != nil || errAPI != nil {
s = "failed"
}
metrics.ServiceRequestCounter.With(prometheus.Labels{
status.MetricLabelHandler: string(handlerName),
status.MetricLabelStatus: s,
}).Inc()
metrics.ServiceRequestDuration.With(prometheus.Labels{
status.MetricLabelHandler: string(handlerName),
status.MetricLabelStatus: s,
}).Observe(float64(duration.Nanoseconds()))
}
// encodeReply takes an interface and encodes it as JSON
// it returns the resulting JSON and a marshalling error
func encodeReply(reply interface{}) (replyBytes []byte, err error) {
// @TODO: why use marshal indent here???
replyBytes, err = json.MarshalIndent(map[string]interface{}{
"reply": reply,
}, "", " ")
if err != nil {
log.Error(" could not encode reply " + fmt.Sprint(err))
}
return
}