This is my functions.json:
{
"bindings": [
{
"type": "serviceBusTrigger",
"name": "message",
"connection": "ServiceBusConnectionString",
"direction": "in",
"topicName": "samples-topic",
"subscriptionName": "samples",
"accessRights": "manage"
}
]
}
Is it possible to subscribe to more than one topic for the same function?
Cheers.
Multiple topics are not supported, but you can achieve the same results by creating subscriptions to forward messages from the topics you want to use, to a target topic you can use from your function.
Another option is to have multiple functions, but the first recommendation would require less maintenance.
Related
Building on an earlier question. The following code is an httptrigger that listed to a gis layer edits and updates. It logs into the queue the url payload. I do not want the payload loaded but a specific repetitive message so that it is overwritten everytime for I do not want to dequeue every now and then. How can I go about this?
import logging
import azure.functions as func
def main(req: func.HttpRequest,msg: func.Out[str]) -> func.HttpResponse:
logging.info('Python HTTP trigger function processed a request.')
input_msg = req.params.get('message')
logging.info(input_msg)
msg.set(req.get_body())
return func.HttpResponse(
"This is a test.",
status_code=200
)
**function.json**
{
"scriptFile": "__init__.py",
"bindings": [
{
"authLevel": "anonymous",
"type": "httpTrigger",
"direction": "in",
"name": "req",
"methods": [
"get",
"post"
]
},
{
"type": "http",
"direction": "out",
"name": "$return"
},
{
"type": "queue",
"direction": "out",
"name": "msg",
"queueName": "outqueue1",
"connection": "AzureStorageQueuesConnectionString"
}
]
}
I do not want the payload loaded but a specific repetitive message so
that it is overwritten everytime for I do not want to dequeue every
now and then.
No, when you put in the same message, It will not overwritten. It just queued in the queue storage.
If you want to process the message in queue, just use queueclient or use queuetrigger of azure function.(queuetrigger of function is based on queueclient, they are basically same.)
This is the API reference of queue:
https://learn.microsoft.com/en-us/python/api/azure-storage-queue/azure.storage.queue?view=azure-python
You can use it to process message in the queue with python code.
And this is the queuetrigger of azure function:(This is already integrated and can be used directly)
https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-storage-queue-trigger?tabs=python
I have a container folder where there are many sub-folders(around 3000), a file can land in any of the sub-folders. I need to react to a blob that's added into a sub-folder. I still can't figure out how to create a blob trigger if files are added to sub-folders.
Example:
Excerpt from function.json:
{
"name": "myblob",
"type": "blobTrigger",
"direction": "in",
"path": "rootContainer/{name}"
}
OK, a function is triggered if I receive the blob in rootContainer folder
Except from function.json:
{
"name": "*/myblob",
"type": "blobTrigger",
"direction": "in",
"path": "rootContainer/{name}"
}
or
{
"name": "myblob",
"type": "blobTrigger",
"direction": "in",
"path": "rootContainer/*/{name}"
}
NOT OK, a function isn't triggered
There are not many questions regarding this problem and they still don't provide a normal answer. Can't find any info in documentation either.
Thanks!
I notice you use */myblob as the name, but this is no use.
For example, if you want the function be triggered when something send to a folder such as test under rootContainer, you need to use this function.json:
{
"bindings": [
{
"name": "myBlob",
"type": "blobTrigger",
"direction": "in",
"path": "rootContainer/test/{name}",
"connection": "AzureWebJobsStorage"
}
]
}
The path needs to be defined at compile time.
I have a simple HTTP trigger Azure Function with multiple Service Bus output bindings. All the bindings are pointing to the same Topic, but they have different Subscriptions. If I was to set this function app through function.json it is pretty straightforward:
{
"bindings": [
{
"authLevel": "function",
"name": "req",
"type": "httpTrigger",
"direction": "in",
"methods": [
"get",
"post"
]
},
{
"name": "$return",
"type": "http",
"direction": "out"
},
{
"type": "serviceBus",
"connection": "SERVICEBUS",
"name": "output",
"topicName": "outtopic",
"subscriptionName": "sub",
"direction": "out"
},
{
"type": "serviceBus",
"connection": "SERVICEBUS",
"name": "output",
"topicName": "outtopic",
"subscriptionName": "sub2",
"direction": "out"
}
],
"disabled": false
}
But I publish my functions via Visual Studio and therefore my Azure Functions are read only in the portal and function.json is automatically generated by VS upon publishing.
The problem is that I cannot figure out how do I setup multiple output bindings pointing to different subscriptions. Currently I have something like this:
[FunctionName("Function2")]
public static async Task<IActionResult> Run(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
[ServiceBus("outtopic", entityType:EntityType.Topic)] IAsyncCollector<string> output,
[ServiceBus("outtopic", entityType: EntityType.Topic)] IAsyncCollector<string> output2,
ILogger log)
{
log.LogInformation("C# HTTP trigger function processed a request.");
string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
await output.AddAsync(requestBody);
return new OkObjectResult("OK");
}
As you can see output and output2 are pointing to the same Topic, but there is no option to specify Subscription.
At this point I am pretty confident that this has not been implemented yet. But I hope there is a workaround maybe?
Try this, add Connection property in the definition, per this example - if by subscription you mean on the azure subscription:
public static void Run([BlobTrigger("inputvideo/{customername}/{date}/{filename}", Connection = "AzureWebJobsStorage")]Stream myBlob,
string customername,
string date,
string filename,
[ServiceBus("detectobjectsqueue",EntityType.Queue, Connection="ServiceBusConnectionString")] IAsyncCollector<string> output,
ILogger log)
Update
Per your comment, I understood that by subscription you mean on topic subscription. In that case, the idea of topic is that all subscriptions receive the message. So you have one publisher, and whoever subscribes to the topic it will receive the message. If you would like to make sure that a specific subscriber receives the message, either implement message filtering(per type for example) on the receiving endpoint or use dedicated queue per subscriber.
Also, conceptually, the publisher should not know who are the subscribers, and the subscriber should not know who is the publisher. If you know who is the subscriber, why not use the REST call for example to the receiving endpoint?
It is not possible to directly put messages into a Topic Subscription, rather every message has to come through a Topic.
To make sure only a particular subscription receives a message, you need to configure the Topic Subscription rule. You can read more about rules in the blog post here.
The goal is to receive in Azure HttpTrigger multipart form (with a text file) in the stream and pipe it to the Azure Blob Storage. While processing, check if the file exceeds SIZE_LIMIT (20 Megabytes), then abort uploading.
Tried to set up function.js like this
{
"bindings": [
{
"authLevel": "anonymous",
"type": "httpTrigger",
"direction": "in",
"name": "req",
"methods": ["post"],
"dataType": "stream",
"route": "myroute"
},
{
"type": "http",
"direction": "out",
"name": "res"
}
],
"disabled": false
}
But in debug I see in the variable req.body Buffer type.
What am I doing wrong? Is it even possible to receive stream in Azure Functions?
For now, it's by design that Nodejs(non-C#) functions read the incoming content as Buffer.
Here's the thread tracking the stream support but it seems not in progress. We may have to operate on the buffer(convert to stream and so on) based on our requirement.
In a given Azure Function, I can have 1 or more output bindings. For example, I might have a blob storage output (writing a file blob to storage) and a queue output (pushing a message into a queue).
For example, if I have this very simple Azure function (written in Node.js)...
module.exports = function (context, req) {
context.log('START: Multi-output function.');
context.bindings.outputBlob = "blob-contents";
context.bindings.outputQueueItem = "{'message': 'hello!'}";
context.done();
};
... with the output bindings set up in function.json as follows...
{
"bindings": [
{
"authLevel": "function",
"type": "httpTrigger",
"direction": "in",
"name": "req"
},
{
"type": "http",
"direction": "out",
"name": "res"
},
{
"type": "blob",
"name": "outputBlob",
"path": "outcontainer/{rand-guid}",
"connection": "AzureWebJobsDashboard",
"direction": "out"
},
{
"type": "queue",
"name": "outputQueueItem",
"queueName": "outqueue",
"connection": "AzureWebJobsDashboard",
"direction": "out"
}
],
"disabled": false
}
... when do the two output bindings actually fire, and in which order?
For the when part of the question:
Do they fire at the point where the function sets the output binding? (e.g. the line of code that sets context.bindings.outputBlob)
Do they fire at/after context.done()?
For the order part of the question:
Do they fire in the order they're seen in the code?
Do they fire in the order they're seen in function.json ?
Output bindings fire after the function execution is completed - after context.done().
The order that you set them in the code has no influence on binding executions.
If you can, treat the actual execution order as the implementation detail and do not rely on it. Having said that, if I'm not mistaken, the actual order will be:
Execute all non-queue bindings in order of function.json
Then, execute all queue bindings in order of function.json
UPDATE: based on this issue and this issue I conclude that order is not guaranteed at the moment.