Unable to use | character in AzureFunctionApp appSettings: - azure-devops

Question

I am setting a load of appSettings in my AzureFunctionApp#1 deployment task - but whenever I try to put each on a new line using the | character I get the error:
##[error]Error: Failed to update App service '{{functionName}}' application settings. Error: BadRequest - Parameter name cannot be empty. (CODE: 400)
The output above that seems to show that it has indeed built the JSON with an empty parameter name. But I don't know why? I've tested with the values on separate lines, and still in a single line, so neither of these work:
appSettings: |
'-Values:Setting1 "$(SettingVal1)"
-Values:Setting2 "$(SettingVal2)"'
appSettings: |
'-Value:Setting1 "$(SettingVal1)" -Values:Setting2 "$(SettingVal2)"'
But this does:
appSettings: '-Value:Setting1 "$(SettingVal1)" -Values:Setting2 "$(SettingVal2)"'
I've also tried without the ' - but that made no difference either.

Answer 1

As per your feedback - Converting my comment as an answer, also tried locally in my system.
Multi-line json input works for setting the multiple values in the app settings as this is the closest way.
appSettings: |
[
{
"name": "APPINSIGHTS_INSTRUMENTATIONKEY",
"value": "$(Key)",
"slotSetting": false
},
{
"name": "MYSQL_DATABASE_NAME",
"value": "$(DB_Name)",
"slotSetting": false
}
]

Answer 2

Multiline JSON doesn't work with the AzureFunctionApp#1 task's appSettings parameter (for some reason).
If you try to use the multiline JSON appSettings with the AzureFunctionApp#1 task, you will get an error: BadRequest - Parameter name cannot be empty. (CODE: 400)
To use the multiline JSON appSettings, you need to use a separate AzureAppServiceSettings#1 task - as mentioned in this document.
I can confirm this works after the AzureFunctionApp#1 task. So my pipeline now has:
steps:
...
- task: AzureFunctionApp#1
displayName: Deploy the Function App
condition: succeeded()
inputs:
azureSubscription: "${{parameters.AppAzureSubscription}}"
appName: "${{parameters.functionAppName}}"
package: "$(Pipeline.Workspace)/drop/$(Build.BuildId).zip"
- task: AzureAppServiceSettings#1
displayName: Update app settings
inputs:
azureSubscription: "${{parameters.AppAzureSubscription}}"
appName: "${{parameters.functionAppName}}"
appSettings: |
[
{
"name": "Values:DbConnectionString",
"value": "$(DbConnectionString)",
"slotSetting": false
},
...
]