Run some ActivityPub tests with a Mastodon partner node and your application in the cloud (future)

Other than WebFinger, for almost anything interesting to happen in the Fediverse, we need at least two servers that can perform HTTPS operations on each other. For example, a “follow” requires the would-be follower Node to post a “follow” activity and the would-be-followed Node to post an “accept” activity in response. Some implementations even require that a key exchange happens first because they only accept requests authenticated with HTTP signatures.

This makes the FediTest setup more complicated. Here is one setup with moderate complexity:

Pre-requisites

• Your application runs at a public DNS hostname and with an official TLS certificate. This could be because you have it installed on some server that’s accessible for the internet, or you tunnel a public DNS name to localhost.

• You (perhaps temporarily) run a server with UBOS Gears that is also publicly accessible. Setting this up takes only a few minutes by clicking through the Amazon EC2 wizard that is described and linked to from here.

• Set up a an official DNS hostname for that server and make sure you wait long enough for DNS information to propagate.

Create a TestPlan that uses your Constellation

The Constellation for the example here consists of two Nodes, one running your own App and one running Mastodon in the cloud.

• Copy a suitable Test Plan as a point of departure, such as:

  % cp examples/testplans/fediverse-follow-manual-saas.json myapp-follow-mastodon-ubos-ec2.json
  

• Find the section in the copy that defines the Constellation by looking for keyword constellation. It looks like this:

          "constellation": {
              "roles": {
                  "leader_node": {
                      "nodedriver": "saas.SaasFediverseNodeDriver",
                      "parameters": null
                  },
                  "follower_node": {
                      "nodedriver": "saas.SaasFediverseNodeDriver",
                      "parameters": null
                  }
              },
              "name": "Any Saas application vs any SaaS application"
          }
  

• You see that it defines two roles: leader_node and follower_node. Decide whether, for this test, you want an Actor in your application to follow an Actor in Mastodon (in which case your application would be at follower_node and Mastodon would be at leader_node) or vice versa.

• Now you fill in parameters for your application, as you probably did before here.

• Now modify the other Node section for Mastodon which will be automatically provisioned on your system running UBOS Gears in the cloud. You need to change the name of the nodedriver, and set a few parameters, so it looks like this:

                      "nodedriver": "mastodon.MastodonUbosNode",
                      "parameters": {
                          "app": "Mastodon",
                          "hostname": "example.com",
                          "sshuri": "ssh://shepherd@example.com",
                          "identity_file": "id_rsa"
                      }
                  }
  

  • app: the name of the application, here Mastodon, mostly for reporting purposes.
  • hostname: the DNS hostname at which your Mastodon instance will run. Make sure the DNS record actually points to your system running UBOS Gears.
  • sshuri: the SSH URI used by FediTest to invoke UBOS Gears commands on your system running UBOS Gears, so it can provision (and unprovision) your Mastodon instance.
  • identity_file: optionally, if you specified a key pair for your EC2 instance that’s not your default keypair, the name of the name of the file that contains the private key with which to connect.

Now run the TestPlan

$ feditest run --testplan myapp-follow-mastodon-ubos-ec2.json --html myapp-follow-mastodon-ubos-ec2-results.html

Open myapp-follow-mastodon-ubos-ec2-results.html to see the results.