Clarify credential inspection and protect request privacy

request_privacy_contract_test.go

@@ -0,0 +1,46 @@
+package promptkit_test
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+	"testing"
+
+	"go.maximumdirect.net/promptkit"
+)
+
+func TestRunRequestFormattingAndJSONProtectDirectCredential(t *testing.T) {
+	markers := []string{"secret-key-marker", "variable-marker", "artifact-body-marker", "message-body-marker", "setting-marker", "schema-path-marker"}
+	request := promptkit.RunRequest{
+		PromptID: "prompt", ProfileID: "profile", APIKey: markers[0],
+		Vars:             map[string]string{"name": markers[1]},
+		Inputs:           map[string]promptkit.ArtifactRef{"input": {Type: promptkit.ArtifactRefInline, Body: markers[2]}},
+		AppendedMessages: []promptkit.RenderedMessage{{Role: promptkit.RoleUser, Content: markers[3]}},
+		Execution:        &promptkit.ExecutionTargetOverride{Model: markers[4]},
+		Validation:       &promptkit.OutputContract{SchemaPath: markers[5]},
+	}
+	for _, rendered := range []string{
+		fmt.Sprintf("%v", request), fmt.Sprintf("%+v", request), fmt.Sprintf("%#v", request),
+		fmt.Sprintf("%v", &request), fmt.Sprintf("%+v", &request), fmt.Sprintf("%#v", &request),
+		request.String(), request.GoString(), (&request).String(), (&request).GoString(),
+	} {
+		for _, marker := range markers {
+			if strings.Contains(rendered, marker) {
+				t.Fatalf("request formatting exposes %q: %s", marker, rendered)
+			}
+		}
+	}
+	for _, value := range []any{request, &request} {
+		encoded, err := json.Marshal(value)
+		if err != nil {
+			t.Fatal(err)
+		}
+		var object map[string]any
+		if err := json.Unmarshal(encoded, &object); err != nil {
+			t.Fatal(err)
+		}
+		if _, found := object["APIKey"]; found || strings.Contains(string(encoded), markers[0]) {
+			t.Fatal("request JSON exposed the direct credential")
+		}
+	}
+}