Why do I get different @CosmosDBInput properties then every documentation I can find?

Question

I want to connect to a Cosmos DB in Azure from Azure Functions written in Java Code in an Maven Project (written in Intellij). The whole thing should be triggered by a HTTP request. The HTTP request part works great. While I just want to read from the database this tutorial still appeared to be a good starting point. The code should look something like this:

@FunctionName("processSensorData")
public void processSensorData(
    @EventHubTrigger(
        name = "msg",
        eventHubName = "", // blank because the value is included in the connection string
        cardinality = Cardinality.ONE,
        connection = "EventHubConnectionString")
        TelemetryItem item,
    @CosmosDBOutput(
        name = "databaseOutput",
        databaseName = "TelemetryDb",
        collectionName = "TelemetryInfo",
        connectionStringSetting = "CosmosDBConnectionString")
        OutputBinding<TelemetryItem> document,
    final ExecutionContext context) {...

Now if I create a new Azure Function Project in Intelij of type HttpTigger and a add an @CosmosDBInput binding (or @CosmosDBOutput binding it does not matter), the system tells me that the parameter "connectionStringSetting" could not be resolved. It appears that a "connection" parameter is required.

I searched on different sources through the internet and asked Chat GPT but everywhere only the connectionStringSetting version is shown. So i am now very confused...

I assume that it is some sorts of version problem? Like e.g. the old version used connectionStringSetting and the later version used the connection parameter?

Also if I directly create an @CosmosDBTrigger function it still appears that he uses the connection parameter.

Furthermore I can add the complete code but it is really just the generated class and other files when i create a Azure Function in Intelij. As the rest works great I assume the problem is with the @CosmosDBTrigger annotation.

Also on first glance it appears that these two parameters work very similar.

In in short: What could be the reason that my code uses the connection parameter and not the connectionStringSetting parameter?

To be clear I am not asking how I can connect to Azure with the connection parameter but I want to understand why I get a different parameter than every source on the internet? (Is it save to use? Am I using an deprecated version with out knowing it? Which of the many versions in the pom.xml is the deprecated one (if any)? etc.)

Answer 1

Thanks for bringing this up. The Tutorial seems outdated, sorry for the bad experience.

The Cosmos DB Bundle/Extension that provides support for Input/Output/Trigger bindings was updated in 2023.

There is a migration guide available here: https://learn.microsoft.com/azure/azure-functions/migrate-cosmos-db-version-3-version-4?tabs=isolated-process&pivots=programming-language-java

In your case, the code should look like:

@FunctionName("processSensorData")
public void processSensorData(
    @EventHubTrigger(
        name = "msg",
        eventHubName = "", // blank because the value is included in the connection string
        cardinality = Cardinality.ONE,
        connection = "EventHubConnectionString")
        TelemetryItem item,
    @CosmosDBOutput(
        name = "databaseOutput",
        databaseName = "TelemetryDb",
        containerName = "TelemetryInfo",
        connection = "CosmosDBConnectionString")
        OutputBinding<TelemetryItem> document,
    final ExecutionContext context) {...

We'll work on updating that tutorial.