前言
在上一篇文章【基于ASP.NET ZERO，开发SaaS版供应链管理系统】中有提到对Webhook功能的扩展改造，本文详细介绍一下具体过程。
Webhook功能操作说明，请参见此文档链接：Webhook数据推送
Webhook功能发布日期：
- ASP.NET Boilerplate（以下简称ABP）在v5.2（2020-02-18）版本中发布了Webhook功能，详细说明，请参见：官方帮助链接；
- ASP.NET ZERO（以下简称ZERO）在v8.2.0（2020-02-20）版本中发布了Webhook功能；
- 我们系统是在2021年4月完成了对Webhook功能的改造：内部接口（用户自行设定接口地址的）、第三方接口（微信内部群、钉钉群、聚水潭API等）。
1、Webhook定义
- 为了区分内部接口与第三方接口，在第三方接口名称前统一附加特定前缀，如：Third.WX.XXX、Third.DD.XXX等；
- 添加定义条目时候设定对应的特性（featureDependency），基于特性功能对不同租户显示或者隐藏定义的条目。
public class AppWebhookDefinitionProvider : WebhookDefinitionProvider
{
public override void SetWebhooks(IWebhookDefinitionContext context)
{
//物料档案 - 全部可见
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T11071001_Created));
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T11071001_Updated));
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T11071001_Deleted));
//生产订单 - 生产管理可见
var featureC = new SimpleFeatureDependency("SCM.C");
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T13041001_Created, featureDependency: featureC));
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T13041001_Updated, featureDependency: featureC));
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T13041001_Deleted, featureDependency: featureC));
context.Manager.Add(new WebhookDefinition(name: AppWebHookNames.T13041001_MRP_Data, featureDependency: featureC));
//...
}
}
- 在CoreModule中添加Webhook定义，并设定参数选项：
public class SCMCoreModule : AbpModule
{
public override void PreInitialize()
{
Configuration.Webhooks.Providers.Add();
Configuration.Webhooks.TimeoutDuration = TimeSpan.FromMinutes(1);
Configuration.Webhooks.IsAutomaticSubscriptionDeactivationEnabled = true;
Configuration.Webhooks.MaxSendAttemptCount = 3;
Configuration.Webhooks.MaxConsecutiveFailCountBeforeDeactivateSubscription = 10;
//...
}
//...
}
2、Webhook订阅
- 前端用户创建Webhook订阅记录（WebhookUri、Webhooks、Headers等），之后传递到后端API；
- 后端API通过WebhookSubscriptionManager添加保存WebhookSubscription（Webhook订阅）：
[AbpAuthorize(AppPermissions.Pages_Administration_WebhookSubscription)]
public class WebhookSubscriptionAppService : SCMAppServiceBase, IWebhookSubscriptionAppService
{
//...
[AbpAuthorize(AppPermissions.Pages_Administration_WebhookSubscription_Create)]
public async Task AddSubscription(WebhookSubscription subscription)
{
subscription.TenantId = AbpSession.TenantId;
await _webHookSubscriptionManager.AddOrUpdateSubscriptionAsync(subscription);
}
//...
}
3、Webhook发布（数据推送）
监测实体事件（CreatedEvent、UpdatedEvent、DeletedEvent）数据，按租户用户创建的Webhook订阅，推送数据：
public class T11071001Syncronizer :
IEventHandler>,
IEventHandler>,
IEventHandler>,
ITransientDependency
{
private readonly IAppWebhookPublisher _appWebhookPublisher;
public T11071001Syncronizer(IAppWebhookPublisher appWebhookPublisher)
{
_appWebhookPublisher = appWebhookPublisher;
}
public void HandleEvent(EntityCreatedEventData eventData)
{
DoWebhook("N", eventData.Entity);
}
public void HandleEvent(EntityUpdatedEventData eventData)
{
DoWebhook("U", eventData.Entity);
}
public void HandleEvent(EntityDeletedEventData eventData)
{
int? tenantId = eventData.Entity.TenantId;
string whName = AppWebHookNames.T11071001_Deleted;
var subscriptions = _appWebhookPublisher.GetSubscriptions(tenantId, whName);
if (subscriptions == null) { return; }
_appWebhookPublisher.PublishWebhookUOW(whName, eventData.Entity, tenantId, subscriptions);
}
}
- DoWebhook()方法：基于具体的订阅（内部接口、第三方接口等）推送对应的内容：
private void DoWebhook(string nu, T11071001 entity)
{
int? tenantId = entity.TenantId;
var whCache = _appWebhookPublisher.GetWebhookCache(tenantId); if (whCache.Count == 0) { return; }
string whName = nu == "N" ? AppWebHookNames.T11071001_Created : AppWebHookNames.T11071001_Updated;
string whNameWX = AppWebHookNames.WX_T11071001_Created;
string whNameDD = AppWebHookNames.DD_T11071001_Created;
bool isWH = whCache.Names.ContainsKey(whName);
bool isWX = whCache.Names.ContainsKey(whNameWX);
bool isDD = whCache.Names.ContainsKey(whNameDD);
if (!(isWH || isWX || isDD)) { return; }
var data = ObjectMapper.Map(entity);
//内部接口
if (isWH)
{
_appWebhookPublisher.PublishWebhookUOW(whName, data, tenantId, whCache.Names[whName], false);
}
//企业微信内部群
if (isWX)
{
var wxData = new WxTCardWebhookDto { template_card = GetWxTCard(data, tenantId, nu) };
_appWebhookPublisher.PublishWebhookUOW(whNameWX, wxData, tenantId, whCache.Names[whNameWX], true);
}
//钉钉内部群
if (isDD)
{
var title = GetNUTitle(nu, L(T));
var mdText = GetNewMarkdown(data, title);
var ddData = new DdMarkdownWebhookDto { markdown = new DdMarkdownContentDto { title = title, text = mdText } };
_appWebhookPublisher.PublishWebhookUOW(whNameDD, ddData, tenantId, whCache.Names[whNameDD], true);
}
}
- GetWebhookCache()方法：实现按租户缓存Webhook订阅的数据：
public SCMWebhookCacheItem GetWebhookCache(int? tenantId)
{
return SetAndGetCache(tenantId);
}
private SCMWebhookCacheItem SetAndGetCache(int? tenantId, string keyName = "SubscriptionCount")
{
int tid = tenantId ?? 0; var cacheKey = $"{keyName}-{tid}";
return _cacheManager.GetSCMWebhookCache().Get(cacheKey, () =>
{
int count = 0;
var names = new Dictionary<string, List>();
UnitOfWorkManager.WithUnitOfWork(() =>
{
using (UnitOfWorkManager.Current.SetTenantId(tenantId))
{
if (_featureChecker.IsEnabled(tid, "SCM.H")) //Feature核查
{
var items = _webhookSubscriptionRepository.GetAllList(e => e.TenantId == tenantId && e.IsActive == true);
count = items.Count;
foreach (var item in items)
{
if (string.IsNullOrWhiteSpace(item.Webhooks)) { continue; }
var whNames = JsonHelper.DeserializeObject<string[]>(item.Webhooks); if (whNames == null) { continue; }
foreach (string whName in whNames)
{
if (names.ContainsKey(whName))
{
names[whName].Add(item.ToWebhookSubscription());
}
else
{
names.Add(whName, new List { item.ToWebhookSubscription() });
}
}
}
}
}
});
return new SCMWebhookCacheItem(count, names);
});
}
- PublishWebhookUOW()方法：替换ABP中WebHookPublisher的默认实现，直接按传入的订阅，通过WebhookSenderJob推送数据：
public void PublishWebhookUOW(string webHookName, object data, int? tenantId, List webhookSubscriptions = null, bool sendExactSameData = false )
{
UnitOfWorkManager.WithUnitOfWork(() =>
{
using (UnitOfWorkManager.Current.SetTenantId(tenantId))
{
Publish(webHookName, data, tenantId, webhookSubscriptions, sendExactSameData);
}
});
}
private void Publish(string webhookName, object data, int? tenantId, List webhookSubscriptions, bool sendExactSameData = false )
{
if (string.IsNullOrWhiteSpace(webhookName)) { return; }
//若无直接传入订阅则按webhookName查询
webhookSubscriptions ??= _webhookSubscriptionRepository.GetAllList(subscriptionInfo =>
subscriptionInfo.TenantId == tenantId &&
subscriptionInfo.IsActive &&
subscriptionInfo.Webhooks.Contains("\"" + webhookName + "\"")
).Select(subscriptionInfo => subscriptionInfo.ToWebhookSubscription()).ToList();
if (webhookSubscriptions.IsNullOrEmpty()) { return; }
var webhookInfo = SaveAndGetWebhookEvent(tenantId, webhookName, data);
foreach (var webhookSubscription in webhookSubscriptions)
{
var jobArgs = new WebhookSenderArgs
{
TenantId = webhookSubscription.TenantId,
WebhookEventId = webhookInfo.Id,
Data = webhookInfo.Data,
WebhookName = webhookInfo.WebhookName,
WebhookSubscriptionId = webhookSubscription.Id,
Headers = webhookSubscription.Headers,
Secret = webhookSubscription.Secret,
WebhookUri = webhookSubscription.WebhookUri,
SendExactSameData = sendExactSameData
};
//指定队列执行任务，由触发事件的server执行
IBackgroundJobClient hangFireClient = new BackgroundJobClient();
hangFireClient.Create(x => x.ExecuteAsync(jobArgs), new EnqueuedState(AppVersionHelper.MachineName));
}
}
- WebhookSenderJob：重写WebhookManager的SignWebhookRequest方法，对于第三方接口，不添加签名的Header：
public override void SignWebhookRequest(HttpRequestMessage request, string serializedBody, string secret)
{
if (request == null)
{
throw new ArgumentNullException(nameof(request));
}
//第三方接口，不添加签名Header
if (IsThirdAPI(request))
{
return;
}
if (string.IsNullOrWhiteSpace(serializedBody))
{
throw new ArgumentNullException(nameof(serializedBody));
}
var secretBytes = Encoding.UTF8.GetBytes(secret);
using (var hasher = new HMACSHA256(secretBytes))
{
request.Content = new StringContent(serializedBody, Encoding.UTF8, "application/json");
var data = Encoding.UTF8.GetBytes(serializedBody);
var sha256 = hasher.ComputeHash(data);
var headerValue = string.Format(CultureInfo.InvariantCulture, SignatureHeaderValueTemplate, BitConverter.ToString(sha256));
request.Headers.Add(SignatureHeaderName, headerValue);
}
}
- WebhookSenderJob：重写WebhookSender的CreateWebhookRequestMessage方法，对于第三方接口，进行特殊处理：
protected override HttpRequestMessage CreateWebhookRequestMessage(WebhookSenderArgs webhookSenderArgs)
{
return webhookSenderArgs.WebhookName switch
{
AppWebHookNames.JST_supplier_upload => JSTHttpRequestMessage(webhookSenderArgs), //聚水潭 - 供应商上传
//...
_ => new HttpRequestMessage(HttpMethod.Post, webhookSenderArgs.WebhookUri)
};
}
- WebhookSenderJob：重写WebhookSender的AddAdditionalHeaders方法, 对于第三方接口，不添加Headers：
protected override void AddAdditionalHeaders(HttpRequestMessage request, WebhookSenderArgs webhookSenderArgs)
{
//第三方接口，不添加Header
if (IsThirdAPI(request))
{
return;
}
foreach (var header in webhookSenderArgs.Headers)
{
if (request.Headers.TryAddWithoutValidation(header.Key, header.Value))
{
continue;
}
if (request.Content.Headers.TryAddWithoutValidation(header.Key, header.Value))
{
continue;
}
throw new Exception($"Invalid Header. SubscriptionId:{webhookSenderArgs.WebhookSubscriptionId},Header: {header.Key}:{header.Value}");
}
}
- WebhookSenderJob：重写WebhookSender的SendHttpRequest方法，处理第三方接口的回传数据：
protected override async Task<(bool isSucceed, HttpStatusCode statusCode, string content)> SendHttpRequest(HttpRequestMessage request)
{
using var client = _httpClientFactory.CreateClient(); //避免使用 new HttpClient()方式
client.Timeout = _webhooksConfiguration.TimeoutDuration;
var response = await client.SendAsync(request);
var isSucceed = response.IsSuccessStatusCode;
var statusCode = response.StatusCode;
var content = await response.Content.ReadAsStringAsync();
//第三方接口，需要处理回传的数据
if (IsThirdAPI(request))
{
string method = TryGetHeader(request.Headers, "ThirdAPI1");
int tenantId = Convert.ToInt32(TryGetHeader(request.Headers, "ThirdAPI2"));
switch (method)
{
case AppWebHookNames.JST_supplier_upload: await JSTSupplierUploadResponse(method, content, tenantId); break;
//...
default: break;
}
}
return (isSucceed, statusCode, content);
}
总结
基于ABP/ZERO的Webhook功能实现，进行一些扩展改造，可以实现业务数据按用户订阅进行推送，包括推送到第三方接口（企业微信群、钉钉等），在很大程度上提升了业务系统的灵活性与实用性。