What causes "下载失败" in huiyadanli/RevokeMsgPatcher?

Select a different GitHub proxy in the proxy dropdown and retry.

huiyadanli/RevokeMsgPatcher · error · Exception

下载失败

Error message

下载失败

What it means

DownloadLatestPackage(url, localDirectory) uses HttpClient.GetAsync to fetch a LiteLoaderQQNT/plugin zip; on any non-success HTTP status (4xx/5xx) it throws a plain Exception('下载失败'). It is the download path used by CheckAndUpdate.

Source

Thrown at RevokeMsgPatcher/Model/LiteLoaderRowData.cs:295

        }

        private async Task<string> DownloadLatestPackage(string url, string localDirectory)
        {
            using (HttpClient client = new HttpClient())
            {
                var response = await client.GetAsync(url);
                if (response.IsSuccessStatusCode)
                {
                    var data = await response.Content.ReadAsByteArrayAsync();
                    var fileName = Path.GetFileName(url);
                    var localPath = Path.Combine(localDirectory, fileName);
                    Directory.CreateDirectory(localDirectory); // 确保目录存在
                    File.WriteAllBytes(localPath, data);
                    return localPath;
                }
                else
                {
                    throw new Exception("下载失败");
                }
            }
        }

        private void DirectoryCopy(string sourceDirName, string destDirName, bool copySubDirs = true)
        {
            DirectoryInfo dir = new DirectoryInfo(sourceDirName);
            DirectoryInfo[] dirs = dir.GetDirectories();

            if (!dir.Exists)
            {
                throw new DirectoryNotFoundException("源目录不存在: " + sourceDirName);
            }

            if (!Directory.Exists(destDirName))
            {
                Directory.CreateDirectory(destDirName);
            }

View on GitHub (pinned to 89cbbb3f0c)

Solutions

Select a different GitHub proxy in the proxy dropdown and retry.
Retry after a short delay (transient 5xx or rate-limit).
Open the constructed URL in a browser to confirm the release asset for that version still exists; if the format changed, wait for a patcher update.

Defensive patterns

Strategy: retry

Validate before calling

string url = FormatUrl(proxyUrl, downloadUrl);
if (string.IsNullOrWhiteSpace(url))
{
    UpdateStatus("下载地址无效");
    return;
}

Try / catch

for (int attempt = 0; attempt < 3; attempt++)
{
    try
    {
        return await DownloadLatestPackage(url, localDirectory);
    }
    catch (Exception ex) when (attempt < 2)
    {
        await Task.Delay(TimeSpan.FromSeconds(2 * (attempt + 1)));
    }
}

Prevention

Let the user pick a working GitHub proxy from the dropdown before downloading.
Surface the HTTP status code in the error so 404 vs rate-limit is distinguishable.
Retry transient failures (5xx / 403) with backoff; fail fast on a hard 404.

When it happens

Trigger: The constructed GitHub download URL returns 404 (release asset renamed/removed), 403 (rate limit), 5xx, or the proxy prefix is malformed so the request fails. The '#{version}' substitution in DownloadUrl produced a dead link.

Common situations: Network/proxy misconfigured or unreachable; GitHub rate-limiting; release tag/asset format changed so the version substitution yields an invalid URL.

Related errors

AI-assisted analysis of huiyadanli/RevokeMsgPatcher@89cbbb3f0c (2026-08-13). Data as JSON: /api/errors/ee43f99af14b3c5d. Report an issue: GitHub.