Size V2 newOrder requests randomly. (#3523)

Prior to this commit all of the `newOrder` requests generated by the
load generator had 1 DNS type identifier. In this commit the
`maxNamesPerCert` parameter that was present in the codebase is fixed
(it was never wired through to config before) and used to size the
orders randomly. Each order will have between 1 and `maxNamesPerCert`
identifiers.

For integration testing we set this at 20. 100 would be more realistic
but we'll start small for now.

test/load-generator/boulder-calls.go

@@ -313,19 +313,24 @@ func randDomain(base string) string {
 // newOrder creates a new pending order object for a random set of domains using
 // the context's account.
 func newOrder(s *State, ctx *context) error {
-	// generate a random(-ish) domain name,  will cause some multiples but not enough to make rate limits annoying!
-	randomDomain := randDomain(s.domainBase)
+	// Pick a random number of names within the constraints of the maxNamesPerCert
+	// parameter
+	orderSize := 1 + mrand.Intn(s.maxNamesPerCert-1)
+	// Generate that many random domain names. There may be some duplicates, we
+	// don't care. The ACME server will collapse those down for us, how handy!
+	dnsNames := []core.AcmeIdentifier{}
+	for i := 0; i <= orderSize; i++ {
+		dnsNames = append(dnsNames, core.AcmeIdentifier{
+			Type:  core.IdentifierDNS,
+			Value: randDomain(s.domainBase),
+		})
+	}
 
 	// create the new order request object
 	initOrder := struct {
 		Identifiers []core.AcmeIdentifier
 	}{
-		Identifiers: []core.AcmeIdentifier{
-			{
-				Type:  core.IdentifierDNS,
-				Value: randomDomain,
-			},
-		},
+		Identifiers: dnsNames,
 	}
 	initOrderStr, err := json.Marshal(&initOrder)
 	if err != nil {

test/load-generator/config/v2-example-config.json

@@ -17,6 +17,7 @@
     "certKeySize": 2048,
     "regEmail": "loadtesting@letsencrypt.org",
     "maxRegs": 20,
+    "maxNamesPerCert": 20,
     "dontSaveState": true,
     "results": "v2-example-latency.json"
 }

test/load-generator/config/v2-integration-test-config.json

@@ -17,5 +17,6 @@
     "certKeySize": 2048,
     "regEmail": "loadtesting@letsencrypt.org",
     "maxRegs": 20,
+    "maxNamesPerCert": 20,
     "dontSaveState": true
 }

test/load-generator/main.go

@@ -21,21 +21,22 @@ type Config struct {
 		RateDelta string   // requests / s^2
 		Runtime   string   // how long to run for
 	}
-	ExternalState string // path to file to load/save registrations etc to/from
-	DontSaveState bool   // don't save changes to external state
-	APIBase       string // ACME API address to send requests to
-	DomainBase    string // base domain name to create authorizations for
-	HTTPOneAddr   string // address to listen for http-01 validation requests on
-	TLSOneAddr    string // address to listen for tls-sni-01 validation requests on
-	RealIP        string // value of the Real-IP header to use when bypassing CDN
-	CertKeySize   int    // size of the key to use when creating CSRs
-	RegEmail      string // email to use in registrations
-	Results       string // path to save metrics to
-	MaxRegs       int    // maximum number of registrations to create
+	ExternalState   string // path to file to load/save registrations etc to/from
+	DontSaveState   bool   // don't save changes to external state
+	APIBase         string // ACME API address to send requests to
+	DomainBase      string // base domain name to create authorizations for
+	HTTPOneAddr     string // address to listen for http-01 validation requests on
+	TLSOneAddr      string // address to listen for tls-sni-01 validation requests on
+	RealIP          string // value of the Real-IP header to use when bypassing CDN
+	CertKeySize     int    // size of the key to use when creating CSRs
+	RegEmail        string // email to use in registrations
+	Results         string // path to save metrics to
+	MaxRegs         int    // maximum number of registrations to create
+	MaxNamesPerCert int    // maximum number of names on one certificate/order
 }
 
 func main() {
-	configPath := flag.String("config", "", "Path to configuration file for WFE load-generator")
+	configPath := flag.String("config", "", "Path to configuration file for load-generator")
 	resultsPath := flag.String("results", "", "Path to latency results file")
 	rateArg := flag.Int("rate", 0, "")
 	runtimeArg := flag.String("runtime", "", "")
@@ -44,13 +45,13 @@ func main() {
 
 	configBytes, err := ioutil.ReadFile(*configPath)
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "Failed to read wfe config file %q: %s\n", *configPath, err)
+		fmt.Fprintf(os.Stderr, "Failed to read load-generator config file %q: %s\n", *configPath, err)
 		os.Exit(1)
 	}
 	var config Config
 	err = json.Unmarshal(configBytes, &config)
 	if err != nil {
-		fmt.Fprintf(os.Stderr, "Failed to parse wfe config file: %s\n", err)
+		fmt.Fprintf(os.Stderr, "Failed to parse load-generator config file: %s\n", err)
 		os.Exit(1)
 	}
 
@@ -73,11 +74,12 @@ func main() {
 		config.DomainBase,
 		config.RealIP,
 		config.MaxRegs,
+		config.MaxNamesPerCert,
 		config.Results,
 		config.RegEmail,
 		config.Plan.Actions,
 	)
-	cmd.FailOnError(err, "Failed to create WFE generator")
+	cmd.FailOnError(err, "Failed to create load generator")
 
 	if config.ExternalState != "" {
 		err = s.Restore(config.ExternalState)
@@ -106,7 +108,7 @@ func main() {
 		Rate:    config.Plan.Rate,
 		Delta:   delta,
 	})
-	cmd.FailOnError(err, "Failed to run WFE load generator")
+	cmd.FailOnError(err, "Failed to run load generator")
 
 	if config.ExternalState != "" && !config.DontSaveState {
 		err = s.Snapshot(config.ExternalState)

test/load-generator/state.go

@@ -340,7 +340,15 @@ func (s *State) Restore(filename string) error {
 }
 
 // New returns a pointer to a new State struct or an error
-func New(apiBase string, keySize int, domainBase string, realIP string, maxRegs int, latencyPath string, userEmail string, operations []string) (*State, error) {
+func New(
+	apiBase string,
+	keySize int,
+	domainBase string,
+	realIP string,
+	maxRegs, maxNamesPerCert int,
+	latencyPath string,
+	userEmail string,
+	operations []string) (*State, error) {
 	certKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
 	if err != nil {
 		return nil, err
@@ -365,16 +373,17 @@ func New(apiBase string, keySize int, domainBase string, realIP string, maxRegs
 		return nil, err
 	}
 	s := &State{
-		client:      client,
-		apiBase:     apiBase,
-		certKey:     certKey,
-		domainBase:  domainBase,
-		callLatency: latencyFile,
-		wg:          new(sync.WaitGroup),
-		realIP:      realIP,
-		maxRegs:     maxRegs,
-		email:       userEmail,
-		respCodes:   make(map[int]*respCode),
+		client:          client,
+		apiBase:         apiBase,
+		certKey:         certKey,
+		domainBase:      domainBase,
+		callLatency:     latencyFile,
+		wg:              new(sync.WaitGroup),
+		realIP:          realIP,
+		maxRegs:         maxRegs,
+		maxNamesPerCert: maxNamesPerCert,
+		email:           userEmail,
+		respCodes:       make(map[int]*respCode),
 	}
 
 	// convert operations strings to methods