Bound Weather API response diagnostics

internal/adapters/weatherapi/client_test.go

@@ -201,8 +201,9 @@ func TestFetchBundleRecordsSourceHash(t *testing.T) {
 }
 
 func TestHTTPErrorIsActionable(t *testing.T) {
+	const marker = "upstream-secret-marker"
 	server := fixtureServer(t, map[string]handlerOverride{
-		"/forecast/hourly": {status: http.StatusBadGateway, body: `upstream failed`},
+		"/forecast/hourly": {status: http.StatusBadGateway, body: marker + strings.Repeat("x", 4096)},
 	}, nil)
 	client := newTestClient(t, server.URL+"/", nil)
 
@@ -213,6 +214,9 @@ func TestHTTPErrorIsActionable(t *testing.T) {
 	if !strings.Contains(err.Error(), "/forecast/hourly") || !strings.Contains(err.Error(), "502") {
 		t.Fatalf("error = %q, want endpoint and status", err.Error())
 	}
+	if strings.Contains(err.Error(), marker) {
+		t.Fatalf("error = %q, must not contain upstream response text", err.Error())
+	}
 }
 
 func TestWarmupRetriesBeforeFetchBundle(t *testing.T) {
@@ -291,6 +295,92 @@ func TestWarmupDoesNotRetryPermanentStatus(t *testing.T) {
 	}
 }
 
+func TestWarmupErrorDiagnosticsRedactResponseBody(t *testing.T) {
+	const marker = "upstream-secret-marker"
+	server := fixtureServer(t, map[string]handlerOverride{
+		defaultWarmupEndpoint: {status: http.StatusNotFound, body: marker + strings.Repeat("x", 4096)},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	_, err := client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want warmup error")
+	}
+	if !strings.Contains(err.Error(), defaultWarmupEndpoint) || !strings.Contains(err.Error(), "404") {
+		t.Fatalf("error = %q, want warmup endpoint and status", err.Error())
+	}
+	if strings.Contains(err.Error(), marker) {
+		t.Fatalf("error = %q, must not contain upstream response text", err.Error())
+	}
+}
+
+func TestFetchAcceptsResponseAtBodyLimit(t *testing.T) {
+	body := paddedJSON(t, `{"data":null}`, int(maxResponseBodyBytes))
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/forecast/narrative": {handler: func(w http.ResponseWriter, r *http.Request) {
+			_, _ = w.Write([]byte(body))
+		}},
+	}, nil)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	if _, err := client.FetchBundle(context.Background()); err != nil {
+		t.Fatalf("FetchBundle() error = %v", err)
+	}
+}
+
+func TestFetchRejectsOversizedResponseWithoutRetry(t *testing.T) {
+	var requested []string
+	var narrativeCalls int
+	oversizedBody := paddedJSON(t, `{"data":null}`, int(maxResponseBodyBytes)) + "x"
+	server := fixtureServer(t, map[string]handlerOverride{
+		"/forecast/narrative": {handler: func(w http.ResponseWriter, r *http.Request) {
+			narrativeCalls++
+			_, _ = w.Write([]byte(oversizedBody))
+		}},
+	}, &requested)
+	client := newTestClient(t, server.URL+"/", nil)
+
+	_, err := client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want oversized response error")
+	}
+	if !strings.Contains(err.Error(), "/forecast/narrative") || !strings.Contains(err.Error(), errResponseBodyTooLarge.Error()) {
+		t.Fatalf("error = %q, want endpoint and response limit", err.Error())
+	}
+	if narrativeCalls != 1 {
+		t.Fatalf("narrative calls = %d, want no retry", narrativeCalls)
+	}
+	if containsPath(requested, "/alerts/active") {
+		t.Fatalf("requested paths = %v, want source failure before later fetches", requested)
+	}
+}
+
+func TestWarmupRejectsOversizedResponseWithoutRetry(t *testing.T) {
+	var requested []string
+	oversizedBody := paddedJSON(t, `{"data":{}}`, int(maxResponseBodyBytes)) + "x"
+	server := fixtureServer(t, map[string]handlerOverride{
+		defaultWarmupEndpoint: {handler: func(w http.ResponseWriter, r *http.Request) {
+			_, _ = w.Write([]byte(oversizedBody))
+		}},
+	}, &requested)
+	client := newTestClient(t, server.URL+"/", nil)
+	client.warmupAttempts = 2
+
+	_, err := client.FetchBundle(context.Background())
+	if err == nil {
+		t.Fatal("FetchBundle() error = nil, want oversized warmup response error")
+	}
+	if !strings.Contains(err.Error(), defaultWarmupEndpoint) || !strings.Contains(err.Error(), errResponseBodyTooLarge.Error()) {
+		t.Fatalf("error = %q, want warmup endpoint and response limit", err.Error())
+	}
+	if got := countPath(requested, defaultWarmupEndpoint); got != 1 {
+		t.Fatalf("warmup requests = %d, want no retry; all requests = %v", got, requested)
+	}
+	if containsPath(requested, "/observations") {
+		t.Fatalf("requested paths = %v, want warmup failure before source fetches", requested)
+	}
+}
+
 func TestFetchRetriesRetryableStatus(t *testing.T) {
 	var hourlyCalls int
 	server := fixtureServer(t, map[string]handlerOverride{
@@ -766,6 +856,14 @@ func fixedNow() time.Time {
 	return time.Date(2026, 5, 29, 15, 0, 0, 0, time.UTC)
 }
 
+func paddedJSON(t *testing.T, value string, size int) string {
+	t.Helper()
+	if len(value) > size {
+		t.Fatalf("JSON value length = %d, exceeds requested size %d", len(value), size)
+	}
+	return value + strings.Repeat(" ", size-len(value))
+}
+
 func containsPath(requested []string, path string) bool {
 	for _, rawURL := range requested {
 		if strings.HasPrefix(rawURL, path+"?") || rawURL == path {