feat(editorial): magazine hero — nano-banana 인프라 + collage 렌더

packages/ai-server/src/config/_container.py

@@ -75,6 +75,14 @@ class InfrastructureContainer(DeclarativeContainer):
         environment=environment,
     )
 
+    # Generic LLM image-gen adapter (raw_posts + editorial_article 모두 사용, #429)
+    nano_banana_client: Singleton[NanoBananaClient] = Singleton(
+        NanoBananaClient,
+        api_key=Callable(lambda env: env.GEMINI_API_KEY, environment),
+        model=Callable(lambda env: env.NANO_BANANA_MODEL, environment),
+        timeout_seconds=Callable(lambda env: env.NANO_BANANA_TIMEOUT, environment),
+    )
+
     # #214 raw_posts_callback_client removed — ai-server writes DB directly.
 
     # ─── Postgres asyncpg pool — assets (raw_posts) vs operation (운영 DB) 분리 (#333, #369) ───
@@ -207,17 +215,10 @@ class RawPostsContainer(DeclarativeContainer):
         database_manager=infrastructure.assets_database_manager,
     )
 
-    # #348 — processor stack (Nano Banana + Gemini Pro + Gemini Flash)
-    nano_banana_client: Singleton[NanoBananaClient] = Singleton(
-        NanoBananaClient,
-        api_key=Callable(lambda env: env.GEMINI_API_KEY, environment),
-        model=Callable(lambda env: env.NANO_BANANA_MODEL, environment),
-        timeout_seconds=Callable(lambda env: env.NANO_BANANA_TIMEOUT, environment),
-    )
-
+    # #348 — processor stack uses InfrastructureContainer.nano_banana_client (#429 이후 공유)
     hero_reframe_service: Singleton[HeroReframeService] = Singleton(
         HeroReframeService,
-        client=nano_banana_client,
+        client=infrastructure.nano_banana_client,
     )
 
     items_parser: Singleton[ItemsParser] = Singleton(
@@ -235,7 +236,7 @@ class RawPostsContainer(DeclarativeContainer):
     # #352 — composite crop + nano-banana 1:1 catalog photo per item.
     items_thumbnail_service: Singleton[ItemsThumbnailService] = Singleton(
         ItemsThumbnailService,
-        client=nano_banana_client,
+        client=infrastructure.nano_banana_client,
         r2=infrastructure.r2_client,
     )
 

packages/ai-server/src/editorial_article/graph.py

@@ -1,7 +1,8 @@
 """Stage 2 multi-source LangGraph 조립.
 
-3-node MVP: fetch_sources → compose_layout → publish.
-실패 시 즉시 종료, error_log 누적, status=failed 마킹은 ARQ task 가 담당.
+4 nodes: fetch_sources → compose_layout → generate_hero → publish.
+fetch / compose 는 fail-fast, generate_hero 는 graceful (실패해도 publish 진행
+하고 source post 이미지를 fallback hero 로 사용).
 """
 
 from __future__ import annotations
@@ -10,6 +11,7 @@
 
 from .nodes.compose_layout import compose_layout_node
 from .nodes.fetch_sources import fetch_sources_node
+from .nodes.generate_hero import generate_hero_node
 from .nodes.publish import publish_node
 from .state import EditorialArticleState
 
@@ -23,6 +25,7 @@ def create_editorial_article_graph():
 
     builder.add_node("fetch_sources", fetch_sources_node)
     builder.add_node("compose_layout", compose_layout_node)
+    builder.add_node("generate_hero", generate_hero_node)
     builder.add_node("publish", publish_node)
 
     builder.add_edge(START, "fetch_sources")
@@ -34,8 +37,10 @@ def create_editorial_article_graph():
     builder.add_conditional_edges(
         "compose_layout",
         _route_after,
-        {"ok": "publish", "failed": END},
+        # generate_hero 는 graceful — 실패해도 publish 로 진행
+        {"ok": "generate_hero", "failed": END},
     )
+    builder.add_edge("generate_hero", "publish")
     builder.add_edge("publish", END)
 
     return builder.compile()

packages/ai-server/src/editorial_article/nodes/generate_hero.py

@@ -0,0 +1,101 @@
+"""generate_hero node — nano-banana 매거진 cover 생성 + R2 업로드.
+
+compose_layout 결과의 angle_title / subtitle / 첫 섹션 텍스트 → 매거진 cover
+prompt → nano-banana → R2 → layout.hero_image_url 갱신.
+
+Graceful fallback: nano-banana / R2 실패 시 graph 는 계속 진행 (publish 가
+기존 hero_image_url — compose_layout 이 source post 에서 픽한 이미지 — 를
+그대로 저장). 실패는 error_log 에만 기록, status='failed' 로 보지 않는다.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import logging
+
+from langchain_core.runnables import RunnableConfig
+
+from src.managers.llm.adapters.nano_banana import NanoBananaClient, NanoBananaError
+from src.managers.storage.r2_client import R2Client
+
+from ..models import MagazineLayout
+
+
+logger = logging.getLogger(__name__)
+
+
+def _build_hero_prompt(layout: MagazineLayout) -> str:
+    intro_section = next((s for s in layout.sections if s.type == "intro"), None)
+    intro_body = (intro_section.body if intro_section and intro_section.body else "")[
+        :400
+    ]
+
+    return f"""Create a high-fashion editorial magazine cover image, 16:9 cinematic composition.
+
+Title: {layout.title}
+Subtitle: {layout.subtitle or ''}
+Editorial mood: {intro_body}
+
+Requirements:
+- Sophisticated, magazine-cover aesthetic (Hypebeast TAGGED-style editorial photography)
+- Strong visual hierarchy — single dominant subject or composition
+- High-end color grading, sharp focus, professional fashion photography lighting
+- NO text overlay, NO logos, NO watermarks — image only
+- 16:9 aspect ratio, optimized for Open Graph / hero banner
+- Avoid generic stock-photo look; aim for editorial intent
+
+Generate the image only."""
+
+
+async def generate_hero_node(state: dict, config: RunnableConfig) -> dict:
+    layout: MagazineLayout | None = state.get("layout")
+    if layout is None:
+        # compose_layout 이 실패했으면 graph 가 publish 로 안 가니 여기 안 옴.
+        return {}
+
+    cfg = (config or {}).get("configurable", {}) or {}
+    nano: NanoBananaClient | None = cfg.get("nano_banana_client")
+    r2: R2Client | None = cfg.get("r2_client")
+
+    if nano is None or r2 is None or not r2.is_configured():
+        logger.info(
+            "generate_hero: nano-banana / R2 not configured — skipping (fallback to source image)"
+        )
+        return {}
+
+    article_id = state["article_id"]
+
+    try:
+        prompt = _build_hero_prompt(layout)
+        image_bytes = await nano.generate(prompt=prompt, aspect_ratio="16:9")
+    except NanoBananaError as exc:
+        logger.warning("generate_hero: nano-banana failed (%s) — fallback", exc)
+        return {"error_log": [f"generate_hero: nano-banana: {exc}"]}
+    except Exception as exc:
+        logger.exception("generate_hero: unexpected error")
+        return {"error_log": [f"generate_hero: {type(exc).__name__}: {exc}"]}
+
+    key = f"editorial-magazines/{article_id}/hero.png"
+    try:
+        result = await asyncio.to_thread(r2.put, key, image_bytes, "image/png")
+    except Exception as exc:
+        logger.warning("generate_hero: R2 upload failed (%s) — fallback", exc)
+        return {"error_log": [f"generate_hero: R2 upload: {exc}"]}
+
+    if not result.url:
+        logger.warning("generate_hero: R2 returned no public URL — fallback")
+        return {}
+
+    updated_layout = layout.model_copy(update={"hero_image_url": result.url})
+
+    # hero 섹션이 있으면 같이 갱신
+    new_sections = []
+    for sec in updated_layout.sections:
+        if sec.type == "hero":
+            new_sections.append(sec.model_copy(update={"image_url": result.url}))
+        else:
+            new_sections.append(sec)
+    updated_layout = updated_layout.model_copy(update={"sections": new_sections})
+
+    logger.info("generate_hero: ok article=%s url=%s", article_id, result.url)
+    return {"layout": updated_layout}

packages/ai-server/src/managers/llm/adapters/nano_banana.py

@@ -84,6 +84,40 @@ async def reframe(
             "nano-banana returned no image (likely safety/policy block)"
         )
 
+    async def generate(
+        self,
+        *,
+        prompt: str,
+        aspect_ratio: str = "16:9",
+        image_size: str = "2K",
+    ) -> bytes:
+        """Text-to-image generation (no input image). Used for editorial hero
+        covers (#429). Same model, same error semantics as `reframe`.
+        """
+        try:
+            resp = await self._client.aio.models.generate_content(
+                model=self._model,
+                contents=[prompt],
+                config=genai_types.GenerateContentConfig(
+                    response_modalities=["IMAGE"],
+                    image_config=genai_types.ImageConfig(
+                        aspect_ratio=aspect_ratio, image_size=image_size
+                    ),
+                ),
+            )
+        except Exception as exc:
+            raise NanoBananaError(f"nano-banana request failed: {exc}") from exc
+
+        for candidate in resp.candidates or []:
+            content = candidate.content
+            for part in (content.parts if content else []) or []:
+                inline = getattr(part, "inline_data", None)
+                if inline and inline.data:
+                    return inline.data
+        raise NanoBananaError(
+            "nano-banana returned no image (likely safety/policy block)"
+        )
+
     @property
     def model(self) -> str:
         return self._model

packages/ai-server/src/managers/queue/worker.py

@@ -122,6 +122,9 @@ async def create_worker(
             )
             # #397 — pipeline 실패 알림 fire-and-forget (env 비면 no-op).
             ctx["telegram_notifier"] = infrastructure_container.telegram_notifier()
+            # #429 — editorial_article 의 generate_hero 노드용 (없으면 graceful fallback)
+            ctx["nano_banana_client"] = infrastructure_container.nano_banana_client()
+            ctx["r2_client"] = infrastructure_container.r2_client()
 
         # Create worker with settings
         worker = Worker(

packages/ai-server/src/services/editorial_article/editorial_article_service.py

@@ -27,6 +27,9 @@ async def editorial_article_job(
         recommendation_id: str,
     ) -> Dict[str, Any]:
         operation_db: DatabaseManager | None = ctx.get("operation_database_manager")
+        # optional — 없으면 generate_hero 가 graceful fallback (source post 이미지 사용)
+        nano_banana = ctx.get("nano_banana_client")
+        r2 = ctx.get("r2_client")
 
         if operation_db is None:
             logger.error("editorial_article_job: operation_database_manager missing")
@@ -46,6 +49,8 @@ async def editorial_article_job(
         config = {
             "configurable": {
                 "operation_database_manager": operation_db,
+                "nano_banana_client": nano_banana,
+                "r2_client": r2,
             }
         }
 

packages/web/lib/components/admin/editorial/magazine/MagazineRenderer.tsx

@@ -26,22 +26,75 @@ interface MagazineRendererProps {
   layout: MagazineLayout;
 }
 
+/**
+ * Collage hero — curation_card 섹션의 image_url 들을 그리드로 묶어 단일 hero
+ * 자리에 배치. 단일 AI hero (nano-banana 생성) 보다:
+ *   - source 이미지 fidelity 보존 → 매거진 내부와 시각적 일관성
+ *   - 추가 LLM 비용 / 시간 0
+ *   - editorial 톤이 자연스럽게 multi-subject 구성
+ *
+ * Fallback: curation_card 이미지가 < 1 개면 단일 hero_image_url 사용.
+ */
+function pickCollageImages(layout: MagazineLayout): string[] {
+  const fromCards = layout.sections
+    .filter((s) => s.type === "curation_card" && Boolean(s.image_url))
+    .map((s) => s.image_url as string);
+  if (fromCards.length > 0) return fromCards.slice(0, 4);
+  return layout.hero_image_url ? [layout.hero_image_url] : [];
+}
+
+function CollageHero({
+  images,
+  title,
+}: {
+  images: string[];
+  title: string;
+}) {
+  if (images.length === 0) return null;
+
+  // 이미지 개수별 grid 패턴 — 1: 단일, 2: 2-up, 3: 1+2, 4: 2x2
+  const layout =
+    images.length === 1
+      ? "grid-cols-1"
+      : images.length === 2
+        ? "grid-cols-2"
+        : images.length === 3
+          ? "grid-cols-3"
+          : "grid-cols-2 grid-rows-2";
+
+  return (
+    <div
+      className={`relative w-full aspect-[16/9] overflow-hidden rounded-lg bg-muted grid gap-1 ${layout}`}
+    >
+      {images.map((src, i) => (
+        <div
+          key={`${src}-${i}`}
+          className={
+            images.length === 3 && i === 0
+              ? "relative row-span-1 col-span-1"
+              : "relative"
+          }
+        >
+          <Image
+            src={src}
+            alt={`${title} ${i + 1}`}
+            fill
+            className="object-cover"
+            sizes="(max-width: 1024px) 50vw, 512px"
+            unoptimized
+          />
+        </div>
+      ))}
+    </div>
+  );
+}
+
 export function MagazineRenderer({ layout }: MagazineRendererProps) {
+  const collage = pickCollageImages(layout);
   return (
     <article className="space-y-12 pb-12">
       <header className="space-y-3">
-        {layout.hero_image_url && (
-          <div className="relative w-full aspect-[16/9] overflow-hidden rounded-lg bg-muted">
-            <Image
-              src={layout.hero_image_url}
-              alt={layout.title}
-              fill
-              className="object-cover"
-              sizes="(max-width: 1024px) 100vw, 1024px"
-              unoptimized
-            />
-          </div>
-        )}
+        <CollageHero images={collage} title={layout.title} />
         <h1 className="text-3xl md:text-4xl font-bold text-foreground tracking-tight">
           {layout.title}
         </h1>
@@ -67,8 +120,9 @@ function SectionView({
   index: number;
 }) {
   switch (section.type) {
+    // hero 는 header 의 collage 가 담당 — 본문에서 또 렌더하면 중복
     case "hero":
-      return <HeroSection section={section} />;
+      return null;
     case "intro":
       return <ProseSection section={section} variant="intro" />;
     case "curation_card":
@@ -82,35 +136,6 @@ function SectionView({
   }
 }
 
-function HeroSection({ section }: { section: MagazineSection }) {
-  return (
-    <section className="space-y-3">
-      {section.image_url && (
-        <div className="relative w-full aspect-[16/9] overflow-hidden rounded-lg bg-muted">
-          <Image
-            src={section.image_url}
-            alt={section.title ?? "Hero"}
-            fill
-            className="object-cover"
-            sizes="(max-width: 1024px) 100vw, 1024px"
-            unoptimized
-          />
-        </div>
-      )}
-      {section.title && (
-        <h2 className="text-2xl font-semibold text-foreground">
-          {section.title}
-        </h2>
-      )}
-      {section.body && (
-        <p className="text-base text-muted-foreground max-w-prose whitespace-pre-line">
-          {section.body}
-        </p>
-      )}
-    </section>
-  );
-}
-
 function ProseSection({
   section,
   variant,