Got the cosmosdb binding working

AzureFunctionsTodo/TodoApiCosmosDb.cs

@@ -9,6 +9,7 @@
 using System.Linq;
 using System;
 using System.Collections.Generic;
+using Microsoft.Azure.Documents.Client;
 
 namespace AzureFunctionsTodo
 {
@@ -24,14 +25,16 @@ public static class TodoApiCosmosDb
                 databaseName: "tododb",
                 collectionName: "tasks",
                 ConnectionStringSetting = "CosmosDBConnection")]
-            IAsyncCollector<Todo> todos, TraceWriter log)
+            IAsyncCollector<object> todos, TraceWriter log)
         {
             log.Info("Creating a new todo list item");
             string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
             var input = JsonConvert.DeserializeObject<TodoCreateModel>(requestBody);
 
             var todo = new Todo() { TaskDescription = input.TaskDescription };
-            await todos.AddAsync(todo);
+            //the object we need to add has to have a lower case id property or we'll
+            // end up with a cosmosdb document with two properties - id (autogenerated) and Id
+            await todos.AddAsync(new { id = todo.Id, todo.CreatedTime, todo.IsCompleted, todo.TaskDescription });
             return new OkObjectResult(todo);
         }
 
@@ -70,42 +73,57 @@ public static class TodoApiCosmosDb
         [FunctionName("CosmosDb_UpdateTodo")]
         public static async Task<IActionResult> UpdateTodo(
             [HttpTrigger(AuthorizationLevel.Anonymous, "put", Route = route + "/{id}")]HttpRequest req,
-            [CosmosDB(databaseName: "tododb", collectionName: "tasks", ConnectionStringSetting = "CosmosDBConnection",
-                Id = "{id}")] Todo todo,
+            [CosmosDB(ConnectionStringSetting = "CosmosDBConnection")]
+                DocumentClient client,
             TraceWriter log, string id)
         {
-
             string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
             var updated = JsonConvert.DeserializeObject<TodoUpdateModel>(requestBody);
-            if (todo == null)
+            Uri collectionUri = UriFactory.CreateDocumentCollectionUri("tododb", "tasks");
+            var document = client.CreateDocumentQuery(collectionUri).Where(t => t.Id == id)
+                            .AsEnumerable().FirstOrDefault();
+            if (document == null)
             {
                 return new NotFoundResult();
             }
 
-            todo.IsCompleted = updated.IsCompleted;
+
+            document.SetPropertyValue("IsCompleted", updated.IsCompleted);
             if (!string.IsNullOrEmpty(updated.TaskDescription))
             {
-                todo.TaskDescription = updated.TaskDescription;
+                document.SetPropertyValue("TaskDescription", updated.TaskDescription);
             }
 
-            // update not implemented yet
+            await client.ReplaceDocumentAsync(document);
 
-            return new OkObjectResult(todo);
+            /* var todo = new Todo()
+            {
+                Id = document.GetPropertyValue<string>("id"),
+                CreatedTime = document.GetPropertyValue<DateTime>("CreatedTime"),
+                TaskDescription = document.GetPropertyValue<string>("TaskDescription"),
+                IsCompleted = document.GetPropertyValue<bool>("IsCompleted")
+            };*/
+
+            // an easier way to deserialize a Document
+            Todo todo2 = (dynamic)document;
+
+            return new OkObjectResult(todo2);
         }
 
         [FunctionName("CosmosDb_DeleteTodo")]
-        public static IActionResult DeleteTodo2(
+        public static async Task<IActionResult> DeleteTodo(
             [HttpTrigger(AuthorizationLevel.Anonymous, "delete", Route = route + "/{id}")]HttpRequest req,
-            [CosmosDB(databaseName: "tododb", collectionName: "tasks", ConnectionStringSetting = "CosmosDBConnection",
-                Id = "{id}")] Todo todo,
+            [CosmosDB(ConnectionStringSetting = "CosmosDBConnection")] DocumentClient client,
             TraceWriter log, string id)
         {
-
-            if (todo == null)
+            Uri collectionUri = UriFactory.CreateDocumentCollectionUri("tododb", "tasks");
+            var document = client.CreateDocumentQuery(collectionUri).Where(t => t.Id == id)
+                    .AsEnumerable().FirstOrDefault();
+            if (document == null)
             {
                 return new NotFoundResult();
             }
-            // delete not implemented - may need to bind to DocumentClient
+            await client.DeleteDocumentAsync(document.SelfLink);
             return new OkResult();
         }
     }

README.md

@@ -7,4 +7,19 @@ A simple CRUD (Create, Read, Update, Delete) API is created to manage TODO items
 - table storage
 - CosmosDb
 
-It's implemented using Azure Functions V2 in C#, and can be run against the local storage emulator for table storage, and the CosmosDb emulator.
+It's implemented using Azure Functions V2 in C#, and can be run against the local storage emulator for table storage, and the CosmosDb emulator.
+
+
+You'll need to set up a `local.settings.json` file containing connection strings for the Azure Storage and Azure CosmosDb emulators
+
+```js
+{
+    "IsEncrypted": false,
+  "Values": {
+    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
+    "AzureWebJobsDashboard": "UseDevelopmentStorage=true",
+    "FUNCTIONS_WORKER_RUNTIME": "dotnet",
+    "CosmosDBConnection": "AccountEndpoint=https://localhost:8081/;AccountKey=C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw=="
+  }
+}
+```