Add LogRequest variable to config input (#5197)

Fixes: DGRAPH-1123

This PR adds support for logRequest config param. logRequest can have true/false values. True
value of logRequest enables logging of all requests coming to alphas. False value of logRequest
disables it.
Users will be able to dynamically change this param using graphql admin endpoint.
Sample query:

mutation {
  config(input: {logRequest: true}){
    response {
      code
      message
    }
  }
}
Internally we have added one more field in WorkerOptions(WorkerConfig) called as LogRequest
of int32 type. Value of this field is checked atomically upon every request arrival. If value of
LogRequest is 1, it results in logging of requests.

Co-authored-by: Ashish Goswami <[email protected]>
(cherry picked from commit 449c06b)

graphql/admin/config.go

@@ -45,7 +45,7 @@ func resolveUpdateConfig(ctx context.Context, m schema.Mutation) (*resolve.Resol
 
 	if input.LruMB > 0 {
 		if err = worker.UpdateLruMb(input.LruMB); err != nil {
-			return resolve.EmptyResult(m, err), false
+			return emptyResult(m, err), false
 		}
 	}
 

x/config.go

@@ -84,8 +84,8 @@ type WorkerOptions struct {
 	StartTime time.Time
 	// LudicrousMode is super fast mode with fewer guarantees.
 	LudicrousMode bool
-	// EncryptionKey is the key used for encryption at rest, backups, exports. Enterprise only feature.
-	EncryptionKey SensitiveByteSlice
+	// BadgerKeyFile is the file containing the key used for encryption. Enterprise only feature.
+	BadgerKeyFile string
 	// LogRequest indicates whether alpha should log all query/mutation requests coming to it.
 	// Ideally LogRequest should be a bool value. But we are reading it using atomics across
 	// queries hence it has been kept as int32. LogRequest value 1 enables logging of requests