AssetManager.API/AssetManager.Services/Services/WechatService.cs

using System.Net.Http;
using System.Text.Json;
using System.Threading.Tasks;

namespace AssetManager.Services.Services;

public class WechatService
{
    private readonly HttpClient _httpClient;
    private readonly string _appId;
    private readonly string _appSecret;

    public WechatService(HttpClient httpClient)
    {
        _httpClient = httpClient;
        // 完全从环境变量读取
        _appId = Environment.GetEnvironmentVariable("Wechat__AppId")
            ?? "wx245f0f3ebcfcf5a7";
        
        _appSecret = Environment.GetEnvironmentVariable("Wechat__AppSecret")
            ?? "809c740129bc8b434177ce12ef292dd0";
    }

    public async Task<WechatAuthResult> GetOpenIdAsync(string code)
    {
        var url = $"https://api.weixin.qq.com/sns/jscode2session?appid={_appId}&secret={_appSecret}&js_code={code}&grant_type=authorization_code";
        var response = await _httpClient.GetAsync(url);
        response.EnsureSuccessStatusCode();
        var content = await response.Content.ReadAsStringAsync();
        return JsonSerializer.Deserialize<WechatAuthResult>(content) ?? new WechatAuthResult();
    }
}

public class WechatAuthResult
{
    public string? OpenId { get; set; }
    public string? SessionKey { get; set; }
    public string? UnionId { get; set; }
    public int Errcode { get; set; }
    public string? Errmsg { get; set; }
}