lakehouse/scripts/serve_imagegen.py

#!/usr/bin/env python3
"""Image generation service — proxies to ComfyUI API on :8188.

Serves on :3600. Submits workflow to ComfyUI, polls for completion, returns image.
Falls back to direct diffusers if ComfyUI is unavailable.

Features:
  - Disk cache — same prompt returns cached image instantly
  - Negative prompt for quality (no faces, hands, text)
  - DreamShaper XL Turbo for high-quality editorial illustrations
"""

import base64
import hashlib
import io
import json
import os
import random
import time
import urllib.request
import urllib.error
from http.server import HTTPServer, BaseHTTPRequestHandler
from pathlib import Path

PORT = int(os.environ.get("IMAGEGEN_PORT", "3600"))
COMFYUI_URL = os.environ.get("COMFYUI_URL", "http://localhost:8188")
CACHE_DIR = Path(os.environ.get("IMAGEGEN_CACHE", "./data/_imagecache"))
CACHE_DIR.mkdir(parents=True, exist_ok=True)
WORKFLOW_PATH = "/opt/ComfyUI/workflows/editorial_hero.json"


def _cache_key(prompt, width, height, steps, seed=None):
    # Include seed so callers can vary outputs deterministically without
    # the proxy collapsing to a single cached image. None == legacy
    # (omitted from the key for backward compatibility).
    bits = f"{prompt}|{width}|{height}|{steps}"
    if seed is not None:
        bits += f"|{seed}"
    return hashlib.sha256(bits.encode()).hexdigest()[:24]

def _cache_get(key):
    fp = CACHE_DIR / f"{key}.webp"
    return base64.b64encode(fp.read_bytes()).decode() if fp.exists() else None

def _cache_put(key, img_bytes):
    (CACHE_DIR / f"{key}.webp").write_bytes(img_bytes)


def _comfyui_generate(prompt, width=1024, height=512, steps=8, seed=None):
    """Submit workflow to ComfyUI and wait for result."""
    # Load workflow template
    with open(WORKFLOW_PATH) as f:
        workflow = json.load(f)

    # Customize
    if seed is None:
        seed = random.randint(0, 2**32)
    workflow["3"]["inputs"]["seed"] = seed
    workflow["3"]["inputs"]["steps"] = steps
    workflow["5"]["inputs"]["width"] = width
    workflow["5"]["inputs"]["height"] = height
    workflow["6"]["inputs"]["text"] = prompt

    # Submit to ComfyUI
    payload = json.dumps({"prompt": workflow}).encode()
    req = urllib.request.Request(
        f"{COMFYUI_URL}/prompt",
        data=payload,
        headers={"Content-Type": "application/json"}
    )
    resp = urllib.request.urlopen(req, timeout=10)
    result = json.loads(resp.read())
    prompt_id = result["prompt_id"]

    # Poll for completion
    for _ in range(120):  # up to 2 minutes
        time.sleep(0.5)
        try:
            status_req = urllib.request.Request(f"{COMFYUI_URL}/history/{prompt_id}")
            status_resp = urllib.request.urlopen(status_req, timeout=5)
            history = json.loads(status_resp.read())
            if prompt_id in history:
                outputs = history[prompt_id].get("outputs", {})
                # Find the SaveImage node output
                for node_id, node_out in outputs.items():
                    images = node_out.get("images", [])
                    if images:
                        img_info = images[0]
                        # Fetch the image
                        img_url = f"{COMFYUI_URL}/view?filename={img_info['filename']}&subfolder={img_info.get('subfolder', '')}&type={img_info.get('type', 'output')}"
                        img_resp = urllib.request.urlopen(img_url, timeout=10)
                        img_data = img_resp.read()
                        # Convert to webp
                        from PIL import Image
                        img = Image.open(io.BytesIO(img_data))
                        buf = io.BytesIO()
                        img.save(buf, format="WEBP", quality=90)
                        return buf.getvalue(), seed
                return None, seed  # completed but no images
        except Exception:
            continue
    return None, seed  # timeout


def _diffusers_fallback(prompt, width, height, steps, seed):
    """Fallback: use raw diffusers SDXL Turbo if ComfyUI is down."""
    import torch
    from diffusers import AutoPipelineForText2Image

    pipe = AutoPipelineForText2Image.from_pretrained(
        "stabilityai/sdxl-turbo", torch_dtype=torch.float16, variant="fp16"
    ).to("cuda")
    pipe.enable_attention_slicing()

    if seed is None:
        seed = random.randint(0, 2**32)
    gen = torch.Generator("cuda").manual_seed(seed)
    result = pipe(prompt=prompt, num_inference_steps=steps, guidance_scale=0.0,
                  width=width, height=height, generator=gen)
    buf = io.BytesIO()
    result.images[0].save(buf, format="WEBP", quality=90)
    del pipe
    torch.cuda.empty_cache()
    return buf.getvalue(), seed


class ImageHandler(BaseHTTPRequestHandler):
    def log_message(self, fmt, *args): pass

    def _json(self, code, data):
        self.send_response(code)
        self.send_header("Content-Type", "application/json")
        self.send_header("Access-Control-Allow-Origin", "*")
        self.end_headers()
        self.wfile.write(json.dumps(data).encode())

    def do_OPTIONS(self):
        self.send_response(200)
        self.send_header("Access-Control-Allow-Origin", "*")
        self.send_header("Access-Control-Allow-Methods", "POST, GET, OPTIONS")
        self.send_header("Access-Control-Allow-Headers", "Content-Type")
        self.end_headers()

    def do_GET(self):
        if self.path == "/health":
            comfy_ok = False
            try:
                r = urllib.request.urlopen(f"{COMFYUI_URL}/system_stats", timeout=3)
                comfy_ok = r.status == 200
            except: pass
            cached = len(list(CACHE_DIR.glob("*.webp")))
            self._json(200, {"status": "ok", "comfyui": comfy_ok, "cached_images": cached})
        elif self.path == "/cache/stats":
            files = list(CACHE_DIR.glob("*.webp"))
            self._json(200, {"count": len(files), "total_mb": round(sum(f.stat().st_size for f in files)/1024**2, 1)})
        else:
            self._json(404, {"error": "not found"})

    def do_POST(self):
        if self.path == "/generate":
            self._generate()
        elif self.path == "/blender":
            self._blender_render()
        elif self.path == "/img-to-3d":
            self._img_to_3d()
        elif self.path == "/scene-glb":
            self._scene_glb()
        else:
            self._json(404, {"error": "not found"})

    def _generate(self):
        try:
            length = int(self.headers.get("Content-Length", 0))
            body = json.loads(self.rfile.read(length)) if length else {}
        except:
            self._json(400, {"error": "invalid JSON"}); return

        prompt = body.get("prompt", "").strip()
        if not prompt:
            self._json(400, {"error": "prompt required"}); return

        width = min(max(int(body.get("width", 1280)), 256), 1920)
        height = min(max(int(body.get("height", 720)), 256), 1080)
        steps = min(max(int(body.get("steps", 50)), 1), 80)
        seed = body.get("seed")

        # Cache check — seed is part of the key so per-worker requests
        # don't collapse to a single cached portrait.
        key = _cache_key(prompt, width, height, steps, seed)
        cached = _cache_get(key)
        if cached:
            self._json(200, {"image": cached, "format": "webp", "width": width, "height": height,
                             "cached": True, "prompt": prompt[:200]}); return

        t0 = time.time()
        img_bytes = None

        # Try ComfyUI first
        try:
            comfy_check = urllib.request.urlopen(f"{COMFYUI_URL}/system_stats", timeout=3)
            if comfy_check.status == 200:
                img_bytes, seed = _comfyui_generate(prompt, width, height, steps, seed)
                backend = "comfyui"
        except:
            pass

        # Fallback to diffusers
        if not img_bytes:
            try:
                img_bytes, seed = _diffusers_fallback(prompt, width, height, steps, seed)
                backend = "diffusers"
            except Exception as e:
                self._json(500, {"error": str(e)[:300]}); return

        if not img_bytes:
            self._json(500, {"error": "generation failed"}); return

        elapsed_ms = int((time.time() - t0) * 1000)
        img_b64 = base64.b64encode(img_bytes).decode()
        # Recompute key with the actual seed used (when caller passed
        # None, _comfyui_generate picks a random one and we want the
        # cache to reflect that so re-requests with the same returned
        # seed hit the disk).
        key = _cache_key(prompt, width, height, steps, seed)
        _cache_put(key, img_bytes)

        self._json(200, {
            "image": img_b64, "format": "webp", "width": width, "height": height,
            "steps": steps, "seed": seed, "time_ms": elapsed_ms,
            "backend": backend, "prompt": prompt[:200], "cached": False,
        })
        print(f"[IMAGEGEN] {backend} {width}x{height} in {elapsed_ms}ms")


    def _blender_render(self):
        """Render a 3D hero banner via Blender Cycles GPU."""
        try:
            length = int(self.headers.get("Content-Length", 0))
            body = json.loads(self.rfile.read(length)) if length else {}
        except:
            self._json(400, {"error": "invalid JSON"}); return

        seed = body.get("seed", random.randint(0, 99999))

        # Cache check
        key = f"blender-{seed}"
        cached = _cache_get(key)
        if cached:
            self._json(200, {"image": cached, "format": "webp", "backend": "blender-cached",
                             "cached": True, "seed": seed}); return

        t0 = time.time()
        output_png = f"/tmp/blender_render_{seed}.png"
        script = "/opt/ComfyUI/blender_scripts/hero_cycles.py"

        try:
            import subprocess
            result = subprocess.run(
                ["blender", "--background", "--python", script, "--", str(seed), output_png],
                capture_output=True, text=True, timeout=300
            )

            if not os.path.exists(output_png):
                self._json(500, {"error": "Blender render failed: " + result.stderr[-300:] if result.stderr else "no output"}); return

            # Convert to webp
            from PIL import Image
            img = Image.open(output_png)
            buf = io.BytesIO()
            img.save(buf, format="WEBP", quality=92)
            img_bytes = buf.getvalue()
            os.remove(output_png)

            elapsed_ms = int((time.time() - t0) * 1000)
            img_b64 = base64.b64encode(img_bytes).decode()
            _cache_put(key, img_bytes)

            self._json(200, {
                "image": img_b64, "format": "webp", "width": 1280, "height": 320,
                "seed": seed, "time_ms": elapsed_ms, "backend": "blender-cycles",
                "cached": False,
            })
            print(f"[BLENDER] Rendered seed={seed} in {elapsed_ms}ms")

        except Exception as e:
            self._json(500, {"error": str(e)[:300]})

    def _img_to_3d(self):
        """Full pipeline: AI image → 3D displacement → Blender render."""
        try:
            length = int(self.headers.get("Content-Length", 0))
            body = json.loads(self.rfile.read(length)) if length else {}
        except:
            self._json(400, {"error": "invalid JSON"}); return

        prompt = body.get("prompt", "abstract flowing golden energy, fractal patterns, dark background, sharp detail").strip()
        seed = body.get("seed", random.randint(0, 99999))

        key = f"img3d-{hashlib.sha256(prompt.encode()).hexdigest()[:12]}-{seed % 4}"
        cached = _cache_get(key)
        if cached:
            self._json(200, {"image": cached, "format": "webp", "backend": "img3d-cached", "cached": True}); return

        t0 = time.time()
        try:
            import subprocess

            # Step 1: Generate source image via ComfyUI directly
            src_path = f"/tmp/img3d_src_{seed}.png"
            try:
                img_bytes_src, _ = _comfyui_generate(prompt, 512, 512, 25, seed)
                if not img_bytes_src:
                    # Fallback to diffusers
                    img_bytes_src, _ = _diffusers_fallback(prompt, 512, 512, 8, seed)
                if not img_bytes_src:
                    self._json(500, {"error": "Failed to generate source image"}); return
                from PIL import Image
                img_src = Image.open(io.BytesIO(img_bytes_src))
                img_src.save(src_path, "PNG")
            except Exception as e:
                self._json(500, {"error": f"Source image failed: {e}"}); return

            # Step 2: TripoSR — convert image to 3D mesh
            mesh_path = f"/tmp/triposr_mesh_{seed}.obj"
            out_path = f"/tmp/img3d_out_{seed}.png"
            try:
                # Free VRAM for TripoSR
                subprocess.run(["systemctl", "stop", "comfyui"], capture_output=True, timeout=10)
                time.sleep(3)

                triposr_script = f"""
import torch, sys
sys.path.insert(0, '/opt/TripoSR')
from PIL import Image
from tsr.system import TSR
model = TSR.from_pretrained('stabilityai/TripoSR', config_name='config.yaml', weight_name='model.ckpt')
model.to('cuda')
image = Image.open('{src_path}').convert('RGB')
with torch.no_grad():
    scene_codes = model([image], device='cuda')
meshes = model.extract_mesh(scene_codes, has_vertex_color=True, resolution=128)
meshes[0].export('{mesh_path}')
del model; torch.cuda.empty_cache()
print('[TRIPOSR] mesh exported')
"""
                result = subprocess.run(
                    ["python3", "-c", triposr_script],
                    capture_output=True, text=True, timeout=120)

                if not os.path.exists(mesh_path):
                    # Fallback to displacement approach
                    print(f"[IMG2-3D] TripoSR failed, falling back to displacement: {result.stderr[-200:]}")
                    script = "/opt/ComfyUI/blender_scripts/image_to_3d.py"
                    result = subprocess.run(
                        ["blender", "--background", "--python", script, "--", src_path, out_path, str(seed)],
                        capture_output=True, text=True, timeout=120)
                else:
                    # Step 3: Render the TripoSR mesh in Blender with gold materials
                    script = "/opt/ComfyUI/blender_scripts/triposr_render.py"
                    result = subprocess.run(
                        ["blender", "--background", "--python", script, "--", mesh_path, out_path, str(seed)],
                        capture_output=True, text=True, timeout=120)
                    try: os.remove(mesh_path)
                    except: pass
            finally:
                # Always restart ComfyUI
                subprocess.run(["systemctl", "start", "comfyui"], capture_output=True, timeout=10)

            if not os.path.exists(out_path):
                self._json(500, {"error": "Blender 3D render failed"}); return

            from PIL import Image
            img = Image.open(out_path)
            buf = io.BytesIO()
            img.save(buf, format="WEBP", quality=92)
            img_bytes = buf.getvalue()

            # Cleanup temp files
            for f in [src_path, out_path]:
                try: os.remove(f)
                except: pass

            elapsed = int((time.time() - t0) * 1000)
            img_b64 = base64.b64encode(img_bytes).decode()
            _cache_put(key, img_bytes)

            self._json(200, {
                "image": img_b64, "format": "webp", "width": 1280, "height": 320,
                "seed": seed, "time_ms": elapsed, "backend": "img-to-3d", "cached": False,
            })
            print(f"[IMG2-3D] seed={seed} prompt={prompt[:50]} in {elapsed}ms")

        except Exception as e:
            self._json(500, {"error": str(e)[:300]})


    def _scene_glb(self):
        """Generate a 3D scene and export as GLB for Three.js viewer."""
        try:
            length = int(self.headers.get("Content-Length", 0))
            body = json.loads(self.rfile.read(length)) if length else {}
        except:
            self._json(400, {"error": "invalid JSON"}); return

        seed = body.get("seed", random.randint(0, 99999))
        key = f"glb-{seed}"

        # Check cache
        glb_cache = CACHE_DIR / f"{key}.glb"
        if glb_cache.exists():
            glb_b64 = base64.b64encode(glb_cache.read_bytes()).decode()
            self._json(200, {"glb": glb_b64, "seed": seed, "cached": True})
            return

        t0 = time.time()
        glb_path = f"/tmp/scene_{seed}.glb"
        try:
            import subprocess
            result = subprocess.run(
                ["blender", "--background", "--python", "/opt/ComfyUI/blender_scripts/export_glb.py",
                 "--", str(seed), glb_path],
                capture_output=True, text=True, timeout=120)

            if not os.path.exists(glb_path):
                self._json(500, {"error": "GLB export failed: " + result.stderr[-200:] if result.stderr else "no output"})
                return

            glb_bytes = open(glb_path, 'rb').read()
            os.remove(glb_path)
            glb_cache.write_bytes(glb_bytes)
            glb_b64 = base64.b64encode(glb_bytes).decode()
            elapsed = int((time.time() - t0) * 1000)

            self._json(200, {"glb": glb_b64, "seed": seed, "time_ms": elapsed, "cached": False})
            print(f"[GLB] seed={seed} in {elapsed}ms size={len(glb_bytes)//1024}KB")

        except Exception as e:
            self._json(500, {"error": str(e)[:300]})


if __name__ == "__main__":
    print(f"[IMAGEGEN] Starting on port {PORT}")
    print(f"[IMAGEGEN] ComfyUI backend: {COMFYUI_URL}")
    print(f"[IMAGEGEN] Cache: {CACHE_DIR}")
    HTTPServer(("0.0.0.0", PORT), ImageHandler).serve_forever()