Merge pull request #107675 from ealsur/users/ealsur/cfpartitionprovided

Cosmos DB - Functions troubleshooting note

Author: PRMerger7

articles/cosmos-db/troubleshoot-changefeed-functions.md

@@ -3,7 +3,7 @@ title: Troubleshoot issues when using Azure Functions trigger for Cosmos DB
 description: Common issues, workarounds, and diagnostic steps, when using the Azure Functions trigger for Cosmos DB
 author: ealsur
 ms.service: cosmos-db
-ms.date: 07/17/2019
+ms.date: 03/13/2020
 ms.author: maquaran
 ms.topic: troubleshooting
 ms.reviewer: sngun
@@ -36,7 +36,7 @@ Additionally, if you are manually creating your own instance of the [Azure Cosmo
 
 Azure Function fails with error message "Either the source collection 'collection-name' (in database 'database-name') or the lease collection 'collection2-name' (in database 'database2-name') does not exist. Both collections must exist before the listener starts. To automatically create the lease collection, set 'CreateLeaseCollectionIfNotExists' to 'true'"
 
-This means that either one or both of the Azure Cosmos containers required for the trigger to work do not exist or are not reachable to the Azure Function. **The error itself will tell you which Azure Cosmos database and containers is the trigger looking for** based on your configuration.
+This means that either one or both of the Azure Cosmos containers required for the trigger to work do not exist or are not reachable to the Azure Function. **The error itself will tell you which Azure Cosmos database and container is the trigger looking for** based on your configuration.
 
 1. Verify the `ConnectionStringSetting` attribute and that it **references a setting that exists in your Azure Function App**. The value on this attribute shouldn't be the Connection String itself, but the name of the Configuration Setting.
 2. Verify that the `databaseName` and `collectionName` exist in your Azure Cosmos account. If you are using automatic value replacement (using `%settingName%` patterns), make sure the name of the setting exists in your Azure Function App.
@@ -47,6 +47,10 @@ This means that either one or both of the Azure Cosmos containers required for t
 
 The previous versions of the Azure Cosmos DB Extension did not support using a leases container that was created within a [shared throughput database](./set-throughput.md#set-throughput-on-a-database). To resolve this issue, update the [Microsoft.Azure.WebJobs.Extensions.CosmosDB](https://www.nuget.org/packages/Microsoft.Azure.WebJobs.Extensions.CosmosDB) extension to get the latest version.
 
+### Azure Function fails to start with "PartitionKey must be supplied for this operation."
+
+This error means that you are currently using a partitioned lease collection with an old [extension dependency](#dependencies). Upgrade to the latest available version. If you are currently running on Azure Functions V1, you will need to upgrade to Azure Functions V2.
+
 ### Azure Function fails to start with "The lease collection, if partitioned, must have partition key equal to id."
 
 This error means that your current leases container is partitioned, but the partition key path is not `/id`. To resolve this issue, you need to recreate the leases container with `/id` as the partition key.
@@ -85,26 +89,26 @@ In this scenario, the best course of action is to add `try/catch` blocks in your
 > [!NOTE]
 > The Azure Functions trigger for Cosmos DB, by default, won't retry a batch of changes if there was an unhandled exception during your code execution. This means that the reason that the changes did not arrive at the destination is because that you are failing to process them.
 
-If, you find that some changes were not received at all by your trigger, the most common scenario is that there is **another Azure Function running**. It could be another Azure Function deployed in Azure or an Azure Function running locally on a developer's machine that has **exactly the same configuration** (same monitored and lease containers), and this Azure Function is stealing a subset of the changes you would expect your Azure Function to process.
+If you find that some changes were not received at all by your trigger, the most common scenario is that there is **another Azure Function running**. It could be another Azure Function deployed in Azure or an Azure Function running locally on a developer's machine that has **exactly the same configuration** (same monitored and lease containers), and this Azure Function is stealing a subset of the changes you would expect your Azure Function to process.
 
-Additionally, the scenario can be validated, if you know how many Azure Function App instances you have running. If you inspect your leases container and count the number of lease items within, the distinct values of the `Owner` property in them should be equal to the number of instances of your Function App. If there are more Owners than the known Azure Function App instances, it means that these extra owners are the one "stealing" the changes.
+Additionally, the scenario can be validated, if you know how many Azure Function App instances you have running. If you inspect your leases container and count the number of lease items within, the distinct values of the `Owner` property in them should be equal to the number of instances of your Function App. If there are more owners than the known Azure Function App instances, it means that these extra owners are the ones "stealing" the changes.
 
-One easy way to workaround this situation, is to apply a `LeaseCollectionPrefix/leaseCollectionPrefix` to your Function with a new/different value or, alternatively, test with a new leases container.
+One easy way to work around this situation, is to apply a `LeaseCollectionPrefix/leaseCollectionPrefix` to your Function with a new/different value or, alternatively, test with a new leases container.
 
-### Need to restart and re-process all the items in my container from the beginning 
-To re-process all the items in a container from the beginning:
+### Need to restart and reprocess all the items in my container from the beginning 
+To reprocess all the items in a container from the beginning:
 1. Stop your Azure function if it is currently running. 
 1. Delete the documents in the lease collection (or delete and re-create the lease collection so it is empty)
 1. Set the [StartFromBeginning](../azure-functions/functions-bindings-cosmosdb-v2-trigger.md#configuration) CosmosDBTrigger attribute in your function to true. 
 1. Restart the Azure function. It will now read and process all changes from the beginning. 
 
-Setting [StartFromBeginning](../azure-functions/functions-bindings-cosmosdb-v2-trigger.md#configuration) to true will tell the Azure function to start reading changes from the beginning of the history of the collection instead of the current time. This only works when there are no already created leases (i.e. documents in the leases collection). Setting this property to true when there are leases already created has no effect; in this scenario, when a function is stopped and restarted, it will begin reading from the last checkpoint, as defined in the leases collection. To re-process from the beginning, follow the above steps 1-4.  
+Setting [StartFromBeginning](../azure-functions/functions-bindings-cosmosdb-v2-trigger.md#configuration) to true will tell the Azure function to start reading changes from the beginning of the history of the collection instead of the current time. This only works when there are no already created leases (that is, documents in the leases collection). Setting this property to true when there are leases already created has no effect; in this scenario, when a function is stopped and restarted, it will begin reading from the last checkpoint, as defined in the leases collection. To reprocess from the beginning, follow the above steps 1-4.  
 
 ### Binding can only be done with IReadOnlyList\<Document> or JArray
 
 This error happens if your Azure Functions project (or any referenced project) contains a manual NuGet reference to the Azure Cosmos DB SDK with a different version than the one provided by the [Azure Functions Cosmos DB Extension](./troubleshoot-changefeed-functions.md#dependencies).
 
-To workaround this situation, remove the manual NuGet reference that was added and let the Azure Cosmos DB SDK reference resolve through the Azure Functions Cosmos DB Extension package.
+To work around this situation, remove the manual NuGet reference that was added and let the Azure Cosmos DB SDK reference resolve through the Azure Functions Cosmos DB Extension package.
 
 ### Changing Azure Function's polling interval for the detecting changes