What causes "Headers JSON格式错误" in babalae/better-genshin-impact?

Use JSON.stringify to build the headers string: JSON.stringify({"content-type": "application/json"}).

babalae/better-genshin-impact · warning · ArgumentException

Headers JSON格式错误

Error message

Headers JSON格式错误

What it means

Thrown as ArgumentException when the headersJson parameter passed to an HTTP method cannot be deserialized into a Dictionary<string, string> by System.Text.Json. This occurs inside a try/catch that catches JsonException specifically — the raw JSON string is malformed, has invalid syntax, or contains values that are not strings.

Source

Thrown at BetterGenshinImpact/Core/Script/Dependence/Http.cs:80

    public async Task<HttpReponse> Request(string method, string url, string? body = null, string? headersJson = null)
    {
        _logger.LogDebug($"[HTTP] 发送HTTP请求: {method} {url} Body: {(body != null ? body : "null")} Headers: {(headersJson != null ? headersJson : "null")}");
        CheckHttpPermission(url);

        var dictHeaders = new Dictionary<string, string>();
        if (!string.IsNullOrWhiteSpace(headersJson))
        {
            try
            {
                var headers = JsonSerializer.Deserialize<Dictionary<string, string>>(headersJson);
                if (headers != null)
                {
                    dictHeaders = headers;
                }
            }
            catch (JsonException)
            {
                throw new ArgumentException("Headers JSON格式错误");
            }
        }

        // header全部小写
        dictHeaders = dictHeaders.ToDictionary(kvp => kvp.Key.ToLowerInvariant(), kvp => kvp.Value);

        // 提前取出来Content-Type，防止被覆盖
        string contentType = "application/json";
        if (dictHeaders.TryGetValue("content-type", out var ct))
        {
            contentType = ct;
            dictHeaders.Remove("content-type");
        }

        // 使用HttpClient发送请求
        using var httpClient = new HttpClient();
        httpClient.DefaultRequestHeaders.Clear();
        foreach (var header in dictHeaders)

View on GitHub (pinned to a7cb36712d)

Solutions

Use JSON.stringify to build the headers string: JSON.stringify({"content-type": "application/json"}).
Ensure all header values are strings: {"authorization": "Bearer xyz"} not {"authorization": 123}.
Validate the JSON before passing: try JSON.parse(headersJson) in the script to catch errors early.
Pass null or empty string for no headers instead of malformed JSON.

Example fix

// before — string concatenation (error-prone)
var headers = '{content-type: application/json, accept: text/html}'; // missing quotes!
http.get(url, headers);

// after — use JSON.stringify
var headers = JSON.stringify({
  "content-type": "application/json",
  "accept": "text/html"
});
http.get(url, headers);

Defensive patterns

Strategy: try-catch

Validate before calling

// Validate headers JSON before passing to HTTP methods
// In JS script context:
// var headers = JSON.stringify({ "content-type": "application/json" });
// var parsed = JSON.parse(headers); // throws if invalid — catches errors early
// http.get(url, headers);

// In C# context:
try
{
    System.Text.Json.JsonSerializer.Deserialize<Dictionary<string, string>>(headersJson);
}
catch (System.Text.Json.JsonException)
{
    throw new ArgumentException("Headers JSON is invalid");
}

Try / catch

try
{
    var resp = http.Get(url, headersJson);
}
catch (ArgumentException ex) when (ex.Message.Contains("Headers JSON格式错误"))
{
    _logger.LogError("Headers JSON is malformed: {Headers}", headersJson);
}

Prevention

Always use JSON.stringify to build headers JSON in scripts.
Ensure all header values are strings, not numbers or booleans.
Validate with JSON.parse before passing to HTTP methods.
Pass null or empty string for no headers instead of invalid JSON.

When it happens

Trigger: Calling http.get(url, headersJson) or http.post(url, body, headersJson) where headersJson is not valid JSON or does not deserialize to Dictionary<string,string>. Examples: trailing comma, single quotes instead of double quotes, numeric values instead of strings, or truncated JSON.

Common situations: Script builds headers JSON by string concatenation instead of JSON.stringify, producing invalid syntax. Header values are numbers/booleans (JSON allows them but Dictionary<string,string> requires strings). Legacy header strings with format issues. Copy-paste from browser DevTools with single-quoted keys.

Related errors

AI-assisted analysis of babalae/better-genshin-impact@a7cb36712d (2026-08-13). Data as JSON: /api/errors/30dfd6bd21632ee7. Report an issue: GitHub.