Output Java Function to DocumentDB

Question

I'm working on a Java Function that has a timer trigger and try to insert a simple record in a DocumentDB collection. The Java code is the following

import java.util.Calendar;
import java.util.UUID;

import com.microsoft.azure.documentdb.Document;
import com.microsoft.azure.serverless.functions.ExecutionContext;
import com.microsoft.azure.serverless.functions.annotation.*;

public class DocumentDBFunction {
    @FunctionName("documentDBFunction")
    @DocumentDBOutput(name = "testdoc",
                  createIfNotExists = true,
                  databaseName = "functiondb",
                  collectionName="functioncoll",
                  connection = "CosmosDBConnectionString")
    public Document functionHandler(
            @TimerTrigger(name = "timerInfo", schedule = "*/30 * * * * *")
            String timerInfo,
            final ExecutionContext executionContext) {

    String randomString=UUID.randomUUID().toString();
    executionContext.getLogger().info("Insert obj documentDB: " + randomString);
    Document document=new Document();
    document.set("id",randomString);
    document.set("_id",randomString);
    document.set("uuid", randomString);
    return document;
    }
}

CosmosDBConnectionString is available in AppSetting and I also created the collection. Function.json is the following

{
  "scriptFile": "../azurefunctions-1.0-SNAPSHOT.jar",
  "entryPoint":     "test.azure.functions.DocumentDBFunction.functionHandler",
  "bindings": [
    {
      "type": "timerTrigger",
      "name": "timerInfo",
      "direction": "in",
      "schedule": "*/30 * * * * *"
    },
    {
      "type": "documentdb",
      "name": "$return",
      "direction": "out",
      "databaseName": "functiondb",
      "collectionName": "functioncoll",
      "connection": "CosmosDBConnectionString",
      "createIfNotExists": true
    }
  ],
  "disabled": false
}

If I run this function I haven'n error on the log files, but there isn't a new object in the DocumentDB collection. Any ideas? Comments and suggestions are welcome

Answer 1

I tried to test your java azure function code on my side.

Java code:

@FunctionName("doc")
@DocumentDBOutput(name = "testdoc",
            createIfNotExists = true,
            databaseName = "db",
            collectionName="coll",
            connection = "CosmosDBConnectionString")
public String functionHandler(
            @TimerTrigger(name = "timerInfo", schedule = "*/30 * * * * *")
                    String timerInfo,
            final ExecutionContext executionContext) {

        String randomString=UUID.randomUUID().toString();
        executionContext.getLogger().info("Insert obj documentDB: " + randomString);
        Document document=new Document();
        document.set("id",randomString);
        document.set("name","Jay!!!");
        return document.toString();
    }

function.json

{
  "scriptFile" : "..\\fabrikam-functions-1.0-SNAPSHOT.jar",
  "entryPoint" : "com.fabrikam.functions.Function.functionHandler",
  "bindings" : [ {
    "type" : "timerTrigger",
    "name" : "timerInfo",
    "direction" : "in",
    "schedule" : "*/30 * * * * *"
  }, {
    "type" : "documentdb",
    "name" : "$return",
    "direction" : "out",
    "databaseName" : "db",
    "collectionName" : "coll",
    "connection" : "CosmosDBConnectionString",
    "createIfNotExists" : true
  } ],
  "disabled" : false
}

The Azure Function runs successfully locally ,but the documents are not be passed into Document DB, as same as you.

I tried to run the same code in Azure and it doesn't show have any difference.

As I know , Java Azure Function is still a preview version and I find the Annotation against Cosmos db for java is N/A.

You could check the webjob dashboard to verify if any error log exist in the table storage which is configured in the AzureWebJobsStorage.

In addition , I suggest you a workaround that you could call the Document DB Java SDK in your TimerTrigger. Please refer to the snippet of code as below:

private static final String account = "***";
private static final String key = "***";

private static DocumentClient client = new DocumentClient("***",
        key, ConnectionPolicy.GetDefault(),
        ConsistencyLevel.Session);

@FunctionName("doc")
public String functionHandler(
        @TimerTrigger(name = "timerInfo", schedule = "*/5 * * * * *")
                String timerInfo,
        final ExecutionContext executionContext) {

    try {
        String randomString = UUID.randomUUID().toString();
        executionContext.getLogger().info("Insert obj documentDB: " + randomString);
        Document document = new Document();
        document.set("id", randomString);
        document.set("name", "Jay!!!");
        client.createDocument("dbs/db/colls/coll",document,null,false);
        return "Insert Success id: "+ randomString;
    } catch (Exception e) {
        executionContext.getLogger().info(e.toString());
        return e.toString();
    }

}

Hope it helps you.