Function installAssetFailureDiagnostics

packages/core/src/runtime/init.ts:1403–1470

()

  };

  const installAssetFailureDiagnostics = () => {
    const assetNodes = Array.from(
      document.querySelectorAll("img, video, audio, source, link[rel='stylesheet']"),
    );
    for (const node of assetNodes) {
      const onError = () => {
        if (!(node instanceof Element)) {
          return;
        }
        const tagName = node.tagName.toLowerCase();
        const assetUrl =
          node.getAttribute("src") ??
          node.getAttribute("href") ??
          node.getAttribute("poster") ??
          null;
        const diagnosticCode =
          tagName === "link" ? "runtime_stylesheet_load_failed" : "runtime_asset_load_failed";
        postRuntimeDiagnosticOnce(
          diagnosticCode,
          {
            tagName,
            assetUrl,
            currentSrc:
              node instanceof HTMLImageElement || node instanceof HTMLMediaElement
                ? node.currentSrc || null
                : null,
            readyState: node instanceof HTMLMediaElement ? node.readyState : null,
            networkState: node instanceof HTMLMediaElement ? node.networkState : null,
          },
          `${diagnosticCode}:${tagName}:${assetUrl ?? "unknown"}`,
        );
      };
      node.addEventListener("error", onError);
      registerRuntimeCleanup(() => {
        node.removeEventListener("error", onError);
      });
    }

    const fontSet = document.fonts;
    if (!fontSet) {
      return;
    }
    void fontSet.ready
      .then(() => {
        if (state.tornDown) {
          return;
        }
        const failedFamilies = Array.from(fontSet)
          .filter((face) => face.status === "error")
          .map((face) => face.family)
          .filter((family) => Boolean(family))
          .slice(0, 10);
        if (failedFamilies.length === 0) {
          return;
        }
        postRuntimeDiagnosticOnce(
          "runtime_font_load_issue",
          {