HttpTrigger not populating binding data from query

[julielerman]

Using v1, I have a function app that uses a route on the HTTP trigger and an id parameter for a CosmosDB input binding.

Here is the function.json for that function:

 "bindings": [
    {
      "authLevel": "anonymous",
      "name": "req",
      "type": "httpTrigger",
      "direction": "in",
      "route": "document/{documentId}"
    },
    {
      "name": "$return",
      "type": "http",
      "direction": "out"
    },
    {
      "type": "documentDB",
      "name": "document",
      "databaseName": "CookieBinge",
      "collectionName": "Binges",
      "connection": "datapointscosmosdb_DOCUMENTDB",
      "direction": "in",
      "id": "{documentId}"
    }
  ],
  "disabled": false
}

My app outputs one of the values from the incoming document. This app is written in C#.
I can use the test feature to pass in a document id and it runs successfully.

I'm building a new function using v2. The binding uses v2 settings.

{
  "type": "cosmosDB",
  "name": "document",
  "databaseName": "Ninjas",
  "collectionName": "Ninjas",
  "connectionStringSetting": "datapointscosmosdb",
  "direction": "in",
   "id": "{documentId}"
}

It fails with internal server errors if I try to test on the portal.
error: One or more errors occurred. (Worker process with pid 6236 exited with code 1) (Worker process with pid 4316 exited with code 1) (Worker process with pid 4728 exited with code 1)
When debugging in VS Code using the extension, the incoming bound document is not a single document but it is all of the docs in the collection.
I can see the documentId value in the context.bindingData.
I've been banging on this problem for a while and thought that maybe I've just hit a bug and it's not me. :)

Investigative information

Please provide the following:

• Timestamp: ??? Don't know how to see this from context in vs code
• Function App version (1.0 or 2.0-beta): 2.0-beta
• Function App name: NinjaFunctions2
• Function name(s) (as appropriate):
• Invocation ID: "1273ffff-ac34-4e99-a2b3-f82b4b6a0194"
• Region:

[pragnagopa]

We have a tracking item Support single Document for binding for adding support to bind to a documentId. Also, here is a related thread with information on the workaround.

[julielerman]

oh! My github search skills aren't so good I guess. glad to know it wasn't me! And I will just use a query for now. Thanks!

[nzthiago]

@pragnagopa @brettsam - I might be missing something, but how does the workaround in that thread in the forums or that tracked item you linked to apply to Julie's HttpTrigger question? Those links only seem to talk about CosmosDBTrigger supporting a single doc which isn't the same.

I've just run into something similar to Julie; trying to get a new c# compiled class v1 or v2 function with an HttpTrigger, to work with a Cosmos DB input binding to retrieve just the one document. I.e., I want to get a query parameter value from the input http trigger being passed in as a query parameter to the input binding as the document id to retrieve. Is that possible? Tried a few things and keep getting a "cannot bind" error to whatever I put in the value of id parameter for the cosmos binding attribute configuration.

[nzthiago]

Ok, to add some more, after some experimentation, using "Route" does make it work to map the id (ratingId in this case) to the Cosmos DB binding, i.e.:

 [HttpTrigger(AuthorizationLevel.Function, "get", Route = "GetRating/{ratingId}")]HttpRequestMessage req, string ratingid,
[DocumentDB("icedteadb", "ratings", Id = "{ratingId}",ConnectionStringSetting = "myCosmosDB")]object queryDoc, TraceWriter log)

So it's only query parameters parts of a JSON body that aren't being mapped from an HttpTrigger to binding expressions. Which I still think should work normally right?

[brettsam]

@nzthiago --

• You are correct, that issue was about the CosmosDBTrigger. This single-item input binding should still work as it did in v1.
• You're also correct that it seems like the query parameters aren't getting bound to the binding data, so we can't find them.
• Can you share the queries that work and don't work from your example above?

@julielerman -- To explain the behavior you're seeing -- I suspect what's happening is that the HttpTrigger binding isn't finding that documentId, so we see Id as null. If we have a null Id and a null SqlQuery for an input binding, we'll retrieve the entire collection.

@mathewc -- are there any known issues with binding data and HttpTrigger? I'm going to update this title as I suspect the problem is there, rather than with the Cosmos extension.

[julielerman]

@brettsam i'm finding it with a standard query and have replaced my original binding with a sqlquery binding. The id binding parameter (above) doesn't seem to be working.

{
  "bindings": [
 
     {
      "authLevel": "anonymous",
      "name": "req",
      "type": "httpTrigger",
      "direction": "in",
      "route": "doc/{documentId}"
    },
    {
      "type": "http",
      "direction": "out",
      "name": "res"
    },
    {
      "type": "cosmosDB",
      "name": "document",
      "databaseName": "Ninjas",
      "collectionName": "Ninjas",
      "connectionStringSetting": "datapointscosmosdb",
      "direction": "in",
      "sqlQuery": "SELECT ninja.id, ninja.Name,ninja.ServedInOniwaban,ninja.DateOfBirth FROM ninja WHERE ninja.id= {documentId}"
     
    }
  ]
}

[brettsam]

What does your HTTP request look like when it works?

[nzthiago]

@brettsam thanks for reopening and looking into this!

By "the queries that work and don't work from your example above", do you mean the HTTP call details? If so, basically any query parameters ( like ?ratingId=1) for a GET won't get mapped to a {ratingId} binding expression. Or, for a post, if I define a POCO with deserialization as per this doc doesn't seem to bind either.

So the workaround we went with that seems to work is a custom route in the HTTPTrigger attribute configuration (the Route = "GetRating/{ratingId}" section I had in my example), and then have that same {ratingId} as the Id value in the CosmosDB binding attribute config, then it works.
The call to this was a GET to the function url + /GetRating/ + the rating id.

[julielerman]

@brettsam do you mean the http request to cosmosdb made by my function? gah ...can't figure out how to see that on my mac. Might have to learn how to use other features of postman. Is there an easy way to capture traffic so I don't have to spend a bunch of time in order to answer the q?