A small sample project to show how you can work with serverless Azure technologies in order to do some realtime DevOps work.
Instead of doing a lot of manual labour, your own logic can handle a lot of mundane tasks for you.
This is still a work in progress...
In order for this project to work, you do need some configuration parameters.
A local.settings.json file should look something like this
{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"TeamsWebhookUrl": "[WebhookUrlToATeamsChannelConfiguredInMicrosoftTeams]",
"FixFailingServicebusUrl": "[TheEndpointToWhateverFixesYourServicebus]"
}
}
The TeamsWebhookUrl is a webhook URL configured in Microsoft Teams which a the service will POST
to whenever an alert is received.
The FixFailingServicebusUrl is the URL which is invoked when the button is pressed in the
Microsoft Teams message to fix the Service Bus issue. In this project we're only making an endpoint
which does nothing, but you probably know what to do when implementing this in your own solution.
Nothing fancy is happening over here. On a real project, this is where you would place the logic to fix the issue (if it can be automated). I'm also returning a reply to the Microsoft Teams message stating the issue has been fixed. Of course, if some exception has occurred, this is also the place where you can edit a message and stating some details on the exception.
This Azure Function should/will be called by Azure Monitor whenever something is wrong on an Azure Servicebus Queue. The Azure Monitor should be configured as a Webhook and the incoming message will look similar to the following message.
{
"schemaId": "azureMonitorCommonAlertSchema",
"data": {
"essentials": {
"alertId": "/subscriptions/3b3734b4-021a-48b5-a2eb-4be0c7e7f44/providers/Microsoft.AlertsManagement/alerts/542dd931-f7c4-4432-adaa-533877e2e76b9",56h "alertRule": "More as 100 messages on queues",
"severity": "Sev3",
"signalType": "Metric",
"monitorCondition": "Fired",
"monitoringService": "Platform",
"alertTargetIDs": [
"/subscriptions/3b3734b4-021a-48b5-a2eb-4be0c7e7f44/resourcegroups/binding-trial/providers/microsoft.servicebus/namespaces/functionbindings"
],
"originAlertId": "3b3729b4-021a-48b5-a2eb-47be0c7e7f44_Binding-trial_microsoft.insights_metricAlerts_More as 100 messages on queues_-1414896316",
"firedDateTime": "2019-05-02T19:32:20.7084714Z",
"description": "",
"essentialsVersion": "1.0",
"alertContextVersion": "1.0"
},
"alertContext": {
"properties": null,
"conditionType": "SingleResourceMultipleMetricCriteria",
"condition": {
"windowSize": "PT5M",
"allOf": [
{
"metricName": "Messages",
"metricNamespace": "Microsoft.ServiceBus/namespaces",
"operator": "GreaterThan",
"threshold": "100",
"timeAggregation": "Average",
"dimensions": [
{
"name": "ResourceId",
"value": "1b3123b4-022a-48b5-a2eb-48be0c7e7f44:functionbindings"
},
{
"name": "EntityName",
"value": "correct-implementation-netframework"
}
],
"metricValue": 10000.0
}
],
"windowStartTime": "2019-05-02T19:23:55.645Z",
"windowEndTime": "2019-05-02T19:28:55.645Z"
}
}
}
}
The incoming
This function is meant to test which is the maximum timeout a response message can take in order to be processed within Teams. You should POST a message to the Microsoft Teams webhook with the following format.
{
"@type": "MessageCard",
"@context": "https://schema.org/extensions",
"summary": "Testing the timeout",
"themeColor": "0078D7",
"sections": [
{
"activityImage": "https://jan-v.nl/Media/logo.png",
"activityTitle": "Timeout test",
"activitySubtitle":"Testing, testing...",
"facts": [
{
"name": "Timeout (miliseconds):",
"value": "5000"
}
],
"text": "The response will return with a timeout of 5000 miliseconds.",
"potentialAction": [
{
"@type": "HttpPOST",
"name": "TimeoutTest",
"target": "https://[yourFunctionApp].azurewebsites.net/api/TimeoutTest?code=[FunctionKey]",
"body": "{\"timeout\": 5000 }"
}
]
}
]
}
This message will have a button triggering the TimeoutTest Azure Function with a specified timeout of 5000 miliseconds.
If you want a higher timeout, you can make it any amount you like.
When the Azure Function returns, it'll create a reply to the original message.
MessageCards have the option to add actions to the card. This action can invoke some endpoint on your API. You might want to check the incoming request on the API to make sure it's from a valid sender.
This specific function is checking if the incoming token (JWT) is valid. I'm using some other code for this, found on an old GitHub repository where such a validator is shared.
No body is necessary, just the Authorization header in the request. This is automatically added by Microsoft Teams
to the potentialAction.