Microsoft Flow is a fantastic enterprise tool and comes with hundreds of default actions, which allow you to easily perform integrations to different services, including Yammer.
Flow gives us several actions out of the box that we can use to perform integration activities against Yammer:
These actions pretty much revolve around fetching and creating messages. True, this is the core thing we do in Yammer, but sometimes our requirements force us to step outside the default capabilities of our platforms and think of creative ways to solve complex problems.
We do a lot of Yammer integrations in our solutions at Rightpoint, and creating a Yammer group is something we do all the time. As we’ve seen, Flow doesn’t give us an action to create Yammer groups, but there is a Yammer API that will do this, and it can be very easily executed via Flow. (Technically speaking, the API to create Yammer groups is an undocumented API. We’ll discuss what that means a little later.)
We’re going to achieve this by POST-ing the necessary data to a Yammer API endpoint, using Flow’s HTTP action. The HTTP action is, in my opinion, the most powerful and flexible Flow component. It’s so powerful because we can literally do anything we want. At a low enough level of abstraction, every action is an HTTP action anyway.
Authenticating to Yammer
The Yammer API uses Oauth tokens to authenticate, so before we start our Flow we’ll need to create an app in Yammer. Navigate to https: //www.yammer.com/YOUR_ORG_NAME/client_applications, and click the green “Register New App” button.
On the “Register New App” screen, fill out the required fields. Absolutely none of the fields in this form have any bearing whatsoever on what we’re doing. If you’re planning to build a web app and publish it in the global Yammer app marketplace, these fields will be needed, but 99.9% of the time they’re pointless. But they’re required fields, so put in whatever will allow the validation to pass.
What we’re really after is the Oauth token. When we save our app, we’ll be redirected to a configuration page where we’ll see the Client ID and Client Secret. By clicking the “Generate a developer token” link, we will expose the app’s token. Don’t worry about the text claiming that this is for testing purposes; they’re still assuming you’re building web apps for the global store. Auth tokens in that case are generated on the client side for each user.
Won’t this Auth token expire?
Yammer app tokens last a long time, although Yammer won’t disclose exactly what the expiration terms are. I can say that I’ve had Yammer integrations authenticating in this fashion since about 2014, and I’ve never seen one expire. They can be revoked, however, and the account that created the app has the ability to do this.
Yammer Apps – other considerations
There are a few things you’ll want to know as you develop Yammer apps in this fashion:
- Anyone can create a Yammer App. You don’t need to be an administrator to do this.
- Yammer Apps execute under the security context of the creating user account. Content created by the app will appear to have been created by the user that created the app. Think of it this way: through the auth token the app author is delegating their access to anyone who holds it.
- If your token is compromised you can invalidate it by navigating to yammer.com/YOUR_ORG_NAME/account/applications and click the “Revoke Access” link next to your app.
- Consider using a dedicated “Service Account” for creation of Yammer Apps. Not only does this protect your user account should the token get compromised, it ensures the token continues to work should your account get disabled – for example, if you leave the organization.
Understanding the Yammer group creation API
If you do any work with the Yammer API, you’ll want to check out the Yammer API documentation.
There you’ll find more detailed information about using the API, and you’ll see a listing of all the supported endpoints exposed via the API.
Notice that there is no listed endpoint to create groups. This is because the group creation endpoint is undocumented. Something to consider when working with undocumented endpoints is that Yammer is not bound to provide support for it, nor will they feel obliged to maintain backward compatibility should they ever decide to update their APIs. So there’s an element of risk to working with these endpoints, and you should be prepared to accept that one morning you might wake up to find that all your stuff is broken. I would counter that by saying Office 365 often imposes breaking changes even on supported stuff, and these APIs have been stable for a number of years running.
The endpoint we use to create groups in Yammer looks like this:
We will POST to this URL, add a content-type of application/json, and add the Yammer Auth token as a bearer token, and leave the body empty. The parameters should be self-evident, and the last two are optional, and they default to a public, listed group.
Let’s test this out. We can use Fiddler or Postman for this, but I’ve recently discovered the Visual Studio Code REST Client extension, and that’s what I’ll be using here. You can read more about it here.
Set your request to look like this:
It’s a simple as that. If you did everything right, you should get a 202 response back and your new group will be shown in Yammer, along with a notification sent to All Company:
Remember, you’ll want to use a service identity, which I didn’t do in this case.
Creating our Flow
Now that we’ve figured out how to post to Yammer using the raw API, let’s incorporate that into a Flow. In my Flow I’m going to use an HTTP trigger, so I can call this as a service from other applications or even from other Flows. We’re going to pass three parameters into our Flow trigger, groupName, isPrivate, and showInDirectory. We’ll use the sample JSON option to generate the request body our trigger will be expecting:
Next we’ll create a variable to construct our REST API URL. Its configuration, using the same URL structure we discussed before, using the Trigger Body JSON to flesh out the parameters, will look like this:
Now we can create and configure our HTTP action:
Now, assuming we’ve hooked everything up properly, we can call our Flow. I’ll be using the VS Code extension again just to keep things simple:
If all goes well we’ll get a 201 response and our group will be present in Yammer:
Note that I passed in parameters to create a private, unlisted group, and you can see this group is private and won’t be listed in the Groups list on Yammer. Also, it doesn’t create the notification message in All Company. Note that the creation of public unlisted groups is unsupported and will cause an error response to be thrown.
Wrapping it up
In this post I showed a technique for integrating the Yammer API with Microsoft Flow, and used it to create groups in Yammer. Using Flow’s HTTP actions we can do just about anything that can be done over HTTP. For more info on the Yammer REST APIs, check out their official documentation.