Send connected SDK message

[smeubank]

Background

At initialization with a valid DSN we want that the SDK sends report to Sentry confirming the connection. And includes some information about what the SDK should be doing. This is really only needed on first init so ideally it is optimized to not send this message too often, or include any identifiable information about where/who it is coming from.

Proposal

Client reports could be reused to send a messsage to sentry on init, it can include some infromation about the SDK config/options being used, but scrubbed to have bare minimum necessary information to assist with Sentry product experience. Dependencies may be an option as well. To start only the message is required.

To ensure this message is not sent too often, we can in a browser environment store in local storage, something along the lines of init report sent:true. This should not have anything about the user and be anonymous while allowing to cut down on the number of requests sent.

[smeubank]

Client reports are a protocol feature that let clients send status reports about themselves to Sentry.

{
  "timestamp": "2020-02-07T14:16:00Z",
  "heartbeat": {
    "sdk": {
      "integrations": ["BrowserTracing", "Replay"],
      "sdkSource": "npm",
      "name": "sentry.javascript.browser",
      "version": "7.25.0"
    },

    // for any option that is a number or boolean we can include the value
    // otherwise we leave it out for security concerns, replace with @null
   // nested config is allowed
   // If you want to include e.g. integration config, you can inline it as a nested object, e.g. `replay: { ... }`
    "options": {
      "sampleRate": 1,
      "beforeSend": null,
      "includeThing": false,
      "whitelist": null,
      "otherThing": null
    },

   "env": {
      "packages": ["[email protected]", "[email protected]", "depWithoutVersion"],
      // other relevant data fields for the env, e.g. for sentry/browser:
      "nodeBuild": "8.6.2"
    }  
  }
}

Consider event processors, SDK vs user implementation

[priscilawebdev]

@smeubank thanks for creating this discussion 🙏

In the JSON above I can see what the heartbeat payload will look like. Are these data already confirmed or are we still defining it? cc @ale-cota

[smeubank]

@priscilawebdev this is the proposal we need to agree upon. @jan-auer wants someone from ingest to take a look possibly @smeubank

other point:
null value can be left out, and other changes can be considered to remove to cut size

[priscilawebdev]

@jan-auer please what are your thoughts on this?