Start Debugging fails to launch

[pgwatinfor]

Version

4.2.1 - 4.2.2

Description

Start Azure Blob Service
Start Debugging(F5)

• Works as expected in v4.1.2
• Fails to launch in v4.2.1 and 4.2.2

Terminal output 4.1.2 OK

Azure Functions Core Tools
Core Tools Version: 4.1.2+9a84203d4b061d9bd9baca563e30ea796d04e115 (64-bit)
Function Runtime Version: 4.1040.300.25317

Skipping 'AzureWebJobsStorage' from local settings as it's already defined in current environment variables.
[2025-10-02T07:06:48.387Z] Worker process started and initialized.

Functions:

    restHandlerTrigger: [GET,POST,DELETE,HEAD,PATCH,PUT,OPTIONS,TRACE,CONNECT] http://localhost:7071/{*segments}

For detailed output, run func with --verbose flag.
[2025-10-02T07:06:53.422Z] Host lock lease acquired by instance ID '00000000000000000000000087AE13C6'._

Terminal output 4.2.1-4.2.2 FAILS

_Azure Functions Core Tools
Core Tools Version: 4.2.2+78afd8b84c8e31f0ddac570ba9e8128eefbd3d4a (64-bit)
Function Runtime Version: 4.1041.200.25360

Skipping 'AzureWebJobsStorage' from local settings as it's already defined in current environment variables.
[2025-10-02T07:14:57.008Z] No job functions found. Try making your job classes and methods public. If you're using binding extensions (e.g. Azure Storage, ServiceBus, Timers, etc.) make sure you've called the registration method for the extension(s) in your startup code (e.g. builder.AddAzureStorage(), builder.AddServiceBus(), builder.AddTimers(), etc.).
For detailed output, run func with --verbose flag.
[2025-10-02T07:15:02.070Z] Host lock lease acquired by instance ID '00000000000000000000000087AE13C6'._

Installed Versions
[INSTALLED] Software Id: "Nodejs" - v20.19.5
[INSTALLED] Software Id: "Npm" - 10.8.2
[INSTALLED] Software Id: "TypeScript" - Version 5.9.2

[INSTALLED] Extension Id: "ms-azuretools.vscode-azurefunctions" Version: 1.19.1 - Azure Functions is installed
[INSTALLED] Extension Id: "Azurite.azurite" Version: 3.35.0 - Azurite is installed
[INSTALLED] Software Id: "AzureCoreTools" - Function Runtime Version: 4.1040.300.25317 Core Tools Version: 4.1.2
[INSTALLED] Software Id: "AzureCoreToolsNPM" - 4.1.2

Steps to reproduce

Install Azure Core Tools v4.2.2
Open the attached HelloWorldNodejs.zip workspace
Start Azurite Blob Service
Start Debugging (F5)

HelloWorldNodeJS.zip

[pgwatinfor]

The issue has been found. It's a boolean casing issue, in v4.1.2 we get “false” but in the v4.2.1-4.2.2 we get “False” ("true" still lowercase) from environment variables loaded from the “local.settings.json” file.

Example from v4.2.1-v4.2.2
"AzureFunctionsJobHost__extensionBundle__ensureLatest": "true",
"AzureFunctionsJobHost__SequentialRestart": "true",
"AzureWebJobs.QueueHandler.Disabled": "False",
"AzureWebJobs.RestHandler.Disabled": "False",
"AzureWebJobs.ScheduledHandler.Disabled": "False",
"AzureWebJobs.StorageHandler.Disabled": "False",

In v4.1.2 it looked like this:
"AzureFunctionsJobHost__extensionBundle__ensureLatest": "true",
"AzureFunctionsJobHost__SequentialRestart": "true",
"AzureWebJobs.QueueHandler.Disabled": "false",
"AzureWebJobs.RestHandler.Disabled": "false",
"AzureWebJobs.ScheduledHandler.Disabled": "false",
"AzureWebJobs.StorageHandler.Disabled": "false",

In the “local.settings.json” file the values are boolean
"AzureWebJobs.RestHandler.Disabled": false,
"AzureWebJobs.StorageHandler.Disabled": false,
"AzureWebJobs.ScheduledHandler.Disabled": false,
"AzureWebJobs.QueueHandler.Disabled": false,

Our fix is to read this value as lower case before we compare it, like this:

if (process.env["AzureWebJobs.RestHandler.Disabled"]?.toLowerCase() == "false") {
app.http("restHandlerTrigger", {
handler: azureRestHandler,
authLevel: "anonymous",
route: "{*segments}",
methods: ["GET", "POST", "DELETE", "HEAD", "PATCH", "PUT", "OPTIONS", "TRACE", "CONNECT"], // All available
});
}