Rename the settings whose names do not say what they control (closes #234)

Applies the setting renames of the naming audit under the SWW_WAF_ and
SWW_RPROXY_ prefixes, with sneak's names for the IP reputation cache
time and the two time limits, which now take milliseconds. The rproxy
log field default_disposition becomes waf_backend_no_answer, and
config.Config and config.FromEnvironment become config.WAF and
config.WAFFromEnvironment. Go fields, test names and prose follow. No
aliases; nothing reads the old names.

Model: opus-5-5

internal/config/rproxy_test.go

@@ -15,20 +15,20 @@ import (
 
 // rproxy's settings, by name, and their values in these tests.
 const (
-	wafBackend        = "SWW_RPROXY_WAF_BACKEND"
-	rproxyTimeout     = "SWW_RPROXY_TIMEOUT_MS"
-	rproxyDefault     = "SWW_RPROXY_DEFAULT_DISPOSITION"
-	rproxyListen      = "SWW_RPROXY_LISTEN_ADDR"
-	rproxyUpstream    = "SWW_RPROXY_UPSTREAM_URL"
-	rproxyTrusted     = "SWW_RPROXY_TRUSTED_PROXIES"
-	rproxyMaxRequest  = "SWW_RPROXY_MAX_REQUEST_SIZE"
-	rproxyMaxResponse = "SWW_RPROXY_MAX_RESPONSE_SIZE"
-	rproxyRequestTime = "SWW_RPROXY_MAX_REQUEST_TIME_MS"
-	rproxyAnswerTime  = "SWW_RPROXY_MAX_RESPONSE_TIME_MS"
-	backendURL        = "http://waf:8080"
-	rproxyDefaultAddr = ":8080"
-	rproxyDefaultApp  = "http://127.0.0.1:8081"
-	notASize          = "a lot"
+	wafBackend         = "SWW_RPROXY_WAF_BACKEND"
+	wafBackendTimeout  = "SWW_RPROXY_WAF_BACKEND_TIMEOUT_MS"
+	rproxyNoAnswer     = "SWW_RPROXY_WAF_BACKEND_NO_ANSWER_DISPOSITION"
+	rproxyListen       = "SWW_RPROXY_LISTEN_ADDR"
+	rproxyUpstream     = "SWW_RPROXY_UPSTREAM_URL"
+	rproxyTrusted      = "SWW_RPROXY_TRUSTED_PROXIES"
+	rproxyMaxRequest   = "SWW_RPROXY_MAX_REQUEST_SIZE"
+	rproxyMaxResponse  = "SWW_RPROXY_MAX_RESPONSE_SIZE"
+	rproxyRequestTime  = "SWW_RPROXY_MAX_REQUEST_TIME_MS"
+	rproxyAnswerTime   = "SWW_RPROXY_MAX_RESPONSE_TIME_MS"
+	backendURL         = "http://waf:8080"
+	rproxyNoAnswerAddr = ":8080"
+	rproxyNoAnswerApp  = "http://127.0.0.1:8081"
+	notASize           = "a lot"
 )
 
 // rproxyConfig reads rproxy's settings from env.
@@ -44,8 +44,8 @@ func TestRProxyDefaults(t *testing.T) {
 		t.Fatalf("settings: %v", err)
 	}
 
-	if cfg.ListenAddr != rproxyDefaultAddr ||
-		cfg.UpstreamURL.String() != rproxyDefaultApp ||
+	if cfg.ListenAddr != rproxyNoAnswerAddr ||
+		cfg.UpstreamURL.String() != rproxyNoAnswerApp ||
 		cfg.WAFBackend.String() != backendURL {
 		t.Errorf(
 			"addresses %q, %v, %v",
@@ -55,11 +55,12 @@ func TestRProxyDefaults(t *testing.T) {
 		)
 	}
 
-	if cfg.Timeout != 2*time.Second || cfg.DefaultDisposition != "allow" {
+	if cfg.WAFBackendTimeout != 2*time.Second ||
+		cfg.WAFBackendNoAnswerDisposition != "allow" {
 		t.Errorf(
-			"timeout %v, default disposition %q",
-			cfg.Timeout,
-			cfg.DefaultDisposition,
+			"waf backend timeout %v, no-answer disposition %q",
+			cfg.WAFBackendTimeout,
+			cfg.WAFBackendNoAnswerDisposition,
 		)
 	}
 
@@ -90,8 +91,8 @@ func TestRProxySettingsAreRead(t *testing.T) {
 		rproxyListen:      ":9000",
 		rproxyUpstream:    "http://app:3000",
 		rproxyTrusted:     "192.0.2.0/24",
-		rproxyTimeout:     "150",
-		rproxyDefault:     "deny",
+		wafBackendTimeout: "150",
+		rproxyNoAnswer:    "deny",
 		rproxyMaxRequest:  "1K",
 		rproxyMaxResponse: off,
 		rproxyRequestTime: off,
@@ -107,8 +108,8 @@ func TestRProxySettingsAreRead(t *testing.T) {
 		t.Errorf("addresses %+v", cfg)
 	}
 
-	if cfg.Timeout != 150*time.Millisecond ||
-		cfg.DefaultDisposition != "deny" ||
+	if cfg.WAFBackendTimeout != 150*time.Millisecond ||
+		cfg.WAFBackendNoAnswerDisposition != "deny" ||
 		cfg.MaxRequestSize != 1024 ||
 		cfg.MaxResponseSize != 0 ||
 		cfg.MaxRequestTime != 0 ||
@@ -126,13 +127,13 @@ func TestRProxyInvalidSettingsAreRefused(t *testing.T) {
 		{wafBackend, ""},
 		{wafBackend, "waf:8080"},
 		{wafBackend, "http://waf:8080/path"},
-		{rproxyTimeout, "0"},
-		{rproxyTimeout, "-1"},
-		{rproxyTimeout, off},
-		{rproxyTimeout, "2s"},
-		{rproxyTimeout, "1.25"},
-		{rproxyTimeout, "99999999999999999"},
-		{rproxyDefault, "maybe"},
+		{wafBackendTimeout, "0"},
+		{wafBackendTimeout, "-1"},
+		{wafBackendTimeout, off},
+		{wafBackendTimeout, "2s"},
+		{wafBackendTimeout, "1.25"},
+		{wafBackendTimeout, "99999999999999999"},
+		{rproxyNoAnswer, "maybe"},
 		{rproxyListen, "8080"},
 		{rproxyUpstream, "app"},
 		{rproxyUpstream, "127.0.0.1:8081"},
@@ -219,11 +220,11 @@ func TestRProxyUnreadableSettingFileStopsTheStart(t *testing.T) {
 
 	for _, path := range []string{filepath.Join(dir, "missing"), dir} {
 		_, err := rproxyConfig(map[string]string{
-			wafBackend:              backendURL,
-			rproxyTimeout + "_FILE": path,
+			wafBackend:                  backendURL,
+			wafBackendTimeout + "_FILE": path,
 		})
 
-		want := rproxyTimeout + "_FILE: cannot be read: "
+		want := wafBackendTimeout + "_FILE: cannot be read: "
 		if err == nil || !strings.HasPrefix(err.Error(), want) {
 			t.Errorf("%s: error %v, want one starting %s", path, err, want)
 		}
@@ -246,7 +247,8 @@ func TestRProxySettingsAreLoggedByName(t *testing.T) {
 	}
 
 	for _, name := range []string{
-		rproxyListen, rproxyUpstream, rproxyTrusted, wafBackend, rproxyTimeout, rproxyDefault,
+		rproxyListen, rproxyUpstream, rproxyTrusted, wafBackend, wafBackendTimeout,
+		rproxyNoAnswer,
 		rproxyMaxRequest, rproxyMaxResponse, rproxyRequestTime, rproxyAnswerTime,
 	} {
 		if !slices.Contains(names, name) {