Add Azure Cosmos DB for MongoDB trigger, input, and output bindings

[xingfan-git]

Summary

This PR adds Node.js SDK support for the Azure Cosmos DB for MongoDB bindings, enabling
developers to trigger functions on MongoDB change stream events and read/write documents
from MongoDB collections using the Azure Functions programming model.

Changes

New Features

• app.cosmosDBMongo() — New function registration method for Cosmos DB for MongoDB
  triggered functions
• trigger.cosmosDBMongo() — New trigger factory for monitoring MongoDB change streams
  (supports Collection / Database / Cluster level)
• input.cosmosDBMongo() — New input binding factory for reading documents from a MongoDB
  collection, with optional queryString filter support
• output.cosmosDBMongo() — New output binding factory for upserting documents into a
  MongoDB collection
• Type definitions for CosmosDBMongoTriggerOptions, CosmosDBMongoTrigger,
  CosmosDBMongoFunctionOptions, CosmosDBMongoHandler, CosmosDBMongoInputOptions,
  CosmosDBMongoInput, CosmosDBMongoOutputOptions, and CosmosDBMongoOutput

Binding Type Strings

Binding	Type string
Trigger	cosmosDBMongoTrigger
Input	cosmosDBMongo
Output	cosmosDBMongo

Tests

Added test/cosmosDBMongo.test.ts with 12 test cases covering trigger, input, and output —
verifying type strings, all binding options, deterministic binding name generation, and
correct direction values via toCoreFunctionMetadata.

[swapnil-nagar]

@xingfan-git do you have a sample app, which would help me validate the changes?

[swapnil-nagar]

Sample app to validate this change

[xingfan-git]

@swapnil-nagar I have added sample code in this repo. If you need a connection string, please let me know

[Copilot]

Pull request overview

This PR adds first-class Node.js programming model support for Azure Cosmos DB for MongoDB bindings, including a new trigger plus input/output binding factories and a sample app.

Changes:

• Adds cosmosDBMongo trigger/input/output factories and app.cosmosDBMongo() registration support.
• Introduces public TypeScript types for Cosmos DB Mongo trigger/input/output options and handler signatures.
• Adds unit tests and a new end-to-end-ish sample project demonstrating usage.

Reviewed changes

Copilot reviewed 14 out of 21 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
types/trigger.d.ts	Exposes trigger.cosmosDBMongo() in public typings.
types/input.d.ts	Exposes input.cosmosDBMongo() in public typings.
types/output.d.ts	Exposes output.cosmosDBMongo() in public typings.
types/app.d.ts	Exposes app.cosmosDBMongo() registration signature.
types/index.d.ts	Re-exports new Cosmos DB Mongo types.
types/cosmosDBMongo.d.ts	Adds new public option/handler/binding type definitions.
src/trigger.ts	Implements trigger.cosmosDBMongo() factory with deterministic binding naming.
src/input.ts	Implements input.cosmosDBMongo() factory with deterministic binding naming.
src/output.ts	Implements output.cosmosDBMongo() factory with deterministic binding naming.
src/app.ts	Implements app.cosmosDBMongo() registration via generic registration path.
test/cosmosDBMongo.test.ts	Adds unit tests validating type strings, option copying, name determinism, and binding directions.
sample/cosmosDBMongo/*	Adds a runnable sample showcasing trigger + HTTP read/write via input/output bindings.

Files not reviewed (1)

• sample/cosmosDBMongo/package-lock.json: Language not supported

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[swapnil-nagar]

Also, as explained this changes will be in preview, hence lets make changes in the package.json with version 4.15.0-preview

[xingfan-git]

PR for e2e test: Azure/azure-functions-nodejs-e2e-tests#88
But I suppose it needs to wait this PR merged as it needs the 4.15.0-preview package

[swapnil-nagar]

PR for e2e test: Azure/azure-functions-nodejs-e2e-tests#88 But I suppose it needs to wait this PR merged as it needs the 4.15.0-preview package

Yes, but that would be a task that you will need after this PR goes through.

[xingfan-git]

@swapnil-nagar I've updated the version to 4.16-preview as current version in v4.x is already 4.15, if it's not correct, please let me know.
The e2e test I have tested locally. Will update to proper version after this PR got merged