Tagging and Sample Data

Use the Appsignal.Span.set_sample_data function to supply extra context on errors and performance issues. This can help to add information that is not already part of the request, session or environment parameters.

1 Appsignal.Span.set_sample_data("tags", %{locale: "en"})

Warning: Do not use tagging to send personal data such as names or email addresses to AppSignal. If you want to identify a person, consider using a user ID, hash or pseudonymized identifier instead. You can use link templates to link them to your own system.

Tags

Using tags you can easily add more information to errors and performance issues tracked by AppSignal. There are a few limitations on tagging though.

The tag key must be a String or Atom.
The tagged value must be a String, Atom or Integer.

Tags that do not meet these limitations are dropped without warning.

set_sample_data can be called multiple times, but only the last value will be retained:

1
2
3 Appsignal.Span.set_sample_data("tags", %{locale: "en"})
Appsignal.Span.set_sample_data("tags", %{user: "bob"})
Appsignal.Span.set_sample_data("tags", %{locale: "de"})

will result in the following data:

1
2
3 %{
  locale: "de"
}

Link templates

Tags can also be used to create link templates. Read more about link templates in our link templates guide.

Sample Data

Besides tags you can add more metadata to a transaction (or override default metadata from integrations such as Phoenix), below is a list of valid keys that can be given to set_sample_data and the format of the value.

`session_data`

Filled with session/cookie data by default, but can be overridden with the following call:

1 Appsignal.Span.set_sample_data("session_data", %{_csrf_token: "Z11CWRVG+I2egpmiZzuIx/qbFb/60FZssui5eGA8a3g="})

This key accepts nested objects that will be rendered as JSON on a Incident Sample page for both Exception and Performance samples.

session_data

`params`

Filled with framework (such as Phoenix) parameters by default, but can be overridden or filled with the following call:

1 Appsignal.Span.set_sample_data("params", %{action: "show", controller: "homepage"})

This key accepts nested objects and will show up as follows on a Incident Sample page for both Exception and Performance samples, formatted as JSON.

params

`environment`

Environment variables from a request/background job, filled by the Phoenix integration, but can be filled/overriden with the following call:

1 Appsignal.Span.set_sample_data("environment", %{CONTENT_LENGTH: "0"})

This call only accepts a one-level key/value object, nested values will be ignored. This will result the following block on a Incident Sample page for both Exception and Performance samples.

environment

`custom_data`

Custom data is not set by default, but can be used to add additional debugging data to solve a performance issue or exception.

1 Appsignal.Span.set_sample_data("custom_data", %{foo: "bar"})

This key accepts nested objects and will result in the following block on a Incident Sample page for both Exception and Performance samples formatted as JSON.

custom_data