我有一个azure函数,我想让它从eventhub获取消息(这相当简单,而且可以工作),然后在运行时使用表绑定将该信息放入表存储。
以下是我目前掌握的情况:
public static async Task Run(string eventHubMessage, TraceWriter log, Binder binder)
{
var m = JsonConvert.DeserializeObject<Measurement>(eventHubMessage);
var attributes = new Attribute[]
{
new StorageAccountAttribute("AzureWebJobsTest"),
new TableAttribute(tableName, m.PartitionKey, m.RowKey)
};
using(var output = await binder.BindAsync<MyTableEntity>(attributes))
{
if(output == null)
log.Info($"4. output is null");
else
{
output.Minimum = m.Minimum;
output.Maximum = m.Maximum;
output.Average = m.Average;
output.Timestamp = m.Timestamp;
output.ETag = m.ETag;
output.WriteEntity(/* Need an operationContext*/)
}
}
}
public class MyTableEntity : TableEntity, IDisposable
{
public double Average { get; set;}
public double Minimum { get; set;}
public double Maximum { get; set;}
bool disposed = false;
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (disposed)
return;
if (disposing)
{
}
disposed = true;
}
}
我的问题;
1)输出始终为空。
2)即使输出不为空,我也不知道需要什么操作上下文,或者调用itableEntity.write()是不是让它写入表存储的正确方法。
eta json绑定:
{
"bindings": [
{
"type": "eventHubTrigger",
"name": "eventHubMessage",
"direction": "in",
"path": "measurements",
"connection": "MeasurementsConnectionString"
}
],
"disabled": false
}
最佳答案
若要向表中添加新条目,应绑定到IAsyncCollector
而不是实体本身,然后创建一个新实体并调用AddAsync
。以下代码片段对我有效:
var attributes = new Attribute[]
{
new StorageAccountAttribute("..."),
new TableAttribute("...")
};
var output = await binder.BindAsync<IAsyncCollector<MyTableEntity>>(attributes);
await output.AddAsync(new MyTableEntity()
{
PartitionKey = "...",
RowKey = "...",
Minimum = ...,
...
});