网页内docker版drawio内嵌和xml生成

app/main.py

@@ -3,10 +3,12 @@ from __future__ import annotations
 import base64
 import json
 import os
+import urllib.error
+import urllib.request
 import zlib
 from pathlib import Path
 from typing import Iterable
-from urllib.parse import unquote
+from urllib.parse import unquote, urljoin
 from xml.etree import ElementTree as ET
 
 from fastapi import FastAPI, HTTPException, Request, Response
@@ -16,6 +18,54 @@ from pydantic import BaseModel
 
 app = FastAPI(title="System Simulation App")
 INDEX_TEMPLATE = Path(__file__).parent / "static" / "index.html"
+DRAWIO_UPSTREAM_URL = (
+    os.getenv("DRAWIO_UPSTREAM_URL")
+    or os.getenv("DRAWIO_BASE_URL")
+    or "http://127.0.0.1:8081/"
+)
+COMPONENT_LIBRARY = [
+    {
+        "title": "\u8d2e\u7bb1",
+        "w": 80,
+        "h": 80,
+        "xml": (
+            '<mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/>'
+            '<object id="tank" label="\u8d2e\u7bb1" componentType="tank" '
+            'medium="N2" volume="1.0"><mxCell style="shape=cylinder;'
+            "whiteSpace=wrap;html=1;boundedLbl=1;backgroundOutline=1;"
+            'size=15;fillColor=#dae8fc;strokeColor=#6c8ebf;" vertex="1" '
+            'parent="1"><mxGeometry width="80" height="80" as="geometry"/>'
+            "</mxCell></object></root></mxGraphModel>"
+        ),
+    },
+    {
+        "title": "\u9600\u95e8",
+        "w": 72,
+        "h": 56,
+        "xml": (
+            '<mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/>'
+            '<object id="valve" label="\u9600\u95e8" componentType="valve" '
+            'valveType="manual" nominalDiameter="10"><mxCell style="rhombus;'
+            'whiteSpace=wrap;html=1;fillColor=#ffe6cc;strokeColor=#d79b00;" '
+            'vertex="1" parent="1"><mxGeometry width="72" height="56" '
+            'as="geometry"/></mxCell></object></root></mxGraphModel>'
+        ),
+    },
+    {
+        "title": "\u7ba1\u6bb5",
+        "w": 96,
+        "h": 36,
+        "xml": (
+            '<mxGraphModel><root><mxCell id="0"/><mxCell id="1" parent="0"/>'
+            '<object id="pipe" label="\u7ba1\u6bb5" componentType="pipe" '
+            'length="1.0" diameter="0.01"><mxCell style="rounded=1;'
+            "whiteSpace=wrap;html=1;arcSize=12;fillColor=#d5e8d4;"
+            'strokeColor=#82b366;" vertex="1" parent="1"><mxGeometry '
+            'width="96" height="36" as="geometry"/></mxCell></object>'
+            "</root></mxGraphModel>"
+        ),
+    },
+]
 
 
 class DiagramPayload(BaseModel):
@@ -25,9 +75,68 @@ class DiagramPayload(BaseModel):
 @app.get("/")
 def index(request: Request) -> HTMLResponse:
     html = INDEX_TEMPLATE.read_text(encoding="utf-8")
-    drawio_base_url = os.getenv("DRAWIO_BASE_URL") or default_drawio_base_url(request)
+    drawio_base_url = default_drawio_base_url(request)
     html = html.replace("__DRAWIO_BASE_URL__", json.dumps(drawio_base_url))
-    return HTMLResponse(html)
+    return HTMLResponse(html, headers={"Cache-Control": "no-store"})
+
+
+@app.get("/api/component-library.drawiolib")
+def component_library() -> Response:
+    library = ET.Element("mxlibrary", {"title": "System Components"})
+    library.text = json.dumps(COMPONENT_LIBRARY, ensure_ascii=False)
+    return Response(
+        content=ET.tostring(library, encoding="utf-8"),
+        media_type="application/xml",
+        headers={
+            "Access-Control-Allow-Origin": "*",
+            "Cache-Control": "no-store",
+        },
+    )
+
+
+@app.api_route("/drawio", methods=["GET", "POST", "HEAD", "OPTIONS"])
+@app.api_route("/drawio/{path:path}", methods=["GET", "POST", "HEAD", "OPTIONS"])
+async def drawio_proxy(request: Request, path: str = "") -> Response:
+    upstream_url = build_drawio_upstream_url(path, request.url.query)
+    body = await request.body()
+    headers = {
+        key: value
+        for key, value in request.headers.items()
+        if key.lower()
+        not in {
+            "host",
+            "connection",
+            "content-length",
+            "accept-encoding",
+        }
+    }
+
+    upstream_request = urllib.request.Request(
+        upstream_url,
+        data=body if body else None,
+        headers=headers,
+        method=request.method,
+    )
+
+    try:
+        with urllib.request.urlopen(upstream_request, timeout=30) as upstream_response:
+            content = upstream_response.read()
+            return Response(
+                content=content,
+                status_code=upstream_response.status,
+                headers=filter_proxy_headers(upstream_response.headers),
+            )
+    except urllib.error.HTTPError as exc:
+        return Response(
+            content=exc.read(),
+            status_code=exc.code,
+            headers=filter_proxy_headers(exc.headers),
+        )
+    except urllib.error.URLError as exc:
+        raise HTTPException(
+            status_code=502,
+            detail=f"Unable to reach draw.io upstream: {exc.reason}",
+        ) from exc
 
 
 @app.post("/api/system-xml")
@@ -46,7 +155,35 @@ def default_drawio_base_url(request: Request) -> str:
     if ":" in hostname and not hostname.startswith("["):
         hostname = f"[{hostname}]"
 
-    return f"{request.url.scheme}://{hostname}:8080/"
+    port = f":{request.url.port}" if request.url.port else ""
+    return f"{request.url.scheme}://{hostname}{port}/drawio/"
+
+
+def build_drawio_upstream_url(path: str, query: str) -> str:
+    target = urljoin(DRAWIO_UPSTREAM_URL, path)
+    if query:
+        target = f"{target}?{query}"
+    return target
+
+
+def filter_proxy_headers(headers) -> dict[str, str]:
+    excluded = {
+        "connection",
+        "content-encoding",
+        "content-length",
+        "keep-alive",
+        "proxy-authenticate",
+        "proxy-authorization",
+        "te",
+        "trailer",
+        "transfer-encoding",
+        "upgrade",
+    }
+    return {
+        key: value
+        for key, value in headers.items()
+        if key.lower() not in excluded
+    }
 
 
 def read_graph_model(xml_text: str) -> ET.Element: