Azure Logic App not sending Attachments to slack - azure

Question

Using Logic App in Azure to post message to slack. This works fine with standard text message.
When I change to also post attachment nothing gets sent:
"inputs": {
"host": {
"connection": {
"name": "#parameters('$connections')['slack']['connectionId']"
}
},
"method": "post",
"path": "/chat.postMessage",
"queries": {
"attachments": [
{
"color": "danger",
"fallback": "Azure alert attachment.",
"fields": [
{
"title": "Check list"
},
{
"value": "Check services on VM0 and VM1"
},
{
"value": "If you cannot fix this issue make sure someone else can"
}
],
"pretext": "<!channel> Action required",
"text": "`'#{triggerBody()['context']['name']}'` API down - '#{triggerBody()['context']['resourceName']}' Details: #{body('Http')['id']}",
"ts": 123456789
}
],
"channel": "#devops",
"text": "SYST ALERT"
}
}

Answer 1

Looking into this, it seems that Logic Apps does not support Attachment type. Please upvote in uservoice #
https://feedback.azure.com/forums/287593-logic-apps/suggestions/31896379-add-support-for-attachments-with-slack-post-messag
So with that being the case, how do we do this today. Slack Supports Incoming Webhooks as well as APIs. I enabled this in Logic Apps using chat.PostMessage API for more details on the API look at :
https://api.slack.com/methods/chat.postMessage/test
The basic problem in this approach is the requirement for a token, in my sample i used a test token from
https://api.slack.com/custom-integrations/legacy-tokens
This isn't the best approach (but i was having some issues using the Incoming WebHook will continue trying that approach and post if i have success there) from a Security PoV but does get the Job done. Final working code is as following :
{
"$connections": {
"value": {
"office365": {
"connectionId": "<ConnectionID",
"connectionName": "office365",
"id": "<ID>"
}
}
},
"definition": {
"$schema": "https://schema.management.azure.com/providers/Microsoft.Logic/schemas/2016-06-01/workflowdefinition.json#",
"actions": {
"Condition_3": {
"actions": {
"HTTP": {
"inputs": {
"body": "?token=<Token>&channel=C8270DY6L&attachments=%5B%7B%22fallback%22%3A%22Requiredplain-textsummaryoftheattachment.%22%2C%22color%22%3A%22%2336a64f%22%2C%22pretext%22%3A%22Optionaltextthatappearsabovetheattachmentblock%22%2C%22author_name%22%3A%22BobbyTables%22%2C%22author_link%22%3A%22http%3A%2F%2Fflickr.com%2Fbobby%2F%22%2C%22author_icon%22%3A%22http%3A%2F%2Fflickr.com%2Ficons%2Fbobby.jpg%22%2C%22title%22%3A%22SlackAPIDocumentation%22%2C%22title_link%22%3A%22https%3A%2F%2Fapi.slack.com%2F%22%2C%22text%22%3A%22Optionaltextthatappearswithintheattachment%22%2C%22fields%22%3A%5B%7B%22title%22%3A%22Priority%22%2C%22value%22%3A%22High%22%2C%22short%22%3Afalse%7D%5D%2C%22image_url%22%3A%22http%3A%2F%2Fmy-website.com%2Fpath%2Fto%2Fimage.jpg%22%2C%22thumb_url%22%3A%22http%3A%2F%2Fexample.com%2Fpath%2Fto%2Fthumb.png%22%2C%22footer%22%3A%22SlackAPI%22%2C%22footer_icon%22%3A%22https%3A%2F%2Fplatform.slack-edge.com%2Fimg%2Fdefault_application_icon.png%22%2C%22ts%22%3A123456789%7D%5D&pretty=1",
"method": "POST",
"uri": "https://slack.com/api/chat.postMessage"
},
"runAfter": {},
"type": "Http"
}
},
"expression": "#equals(triggerBody()?['HasAttachment'], True)",
"runAfter": {},
"type": "If"
}
},
"contentVersion": "1.0.0.0",
"outputs": {},
"parameters": {
"$connections": {
"defaultValue": {},
"type": "Object"
}
},
"triggers": {
"When_a_new_email_arrives": {
"inputs": {
"host": {
"connection": {
"name": "#parameters('$connections')['office365']['connectionId']"
}
},
"method": "get",
"path": "/Mail/OnNewEmail",
"queries": {
"folderPath": "Inbox",
"importance": "Normal"
}
},
"recurrence": {
"frequency": "Minute",
"interval": 3
},
"splitOn": "#triggerBody()?['value']",
"type": "ApiConnection"
}
}
}
}