Attributes

Attributes are stored as key-value pairs where each value is an object with type information.

{
  "my_attribute": {
    "value": "some value",
    "type": "string"
  },
  "response_time": {
    "value": 123,
    "unit": "millisecond",
    "type": "integer"
  },
  "my_list": {
    "value": [1, 2, 3],
    "type": "array"
  }
}

The following primitive types are supported:

• string
• boolean
• integer (64-bit signed integer)
• double (64-bit floating point number)

Note on Integers: Integers should be 64-bit signed integers. For 64-bit unsigned integers, use the string type to avoid overflow issues until unsigned integers are natively supported.

Sentry currently only supports ingesting homogeneous arrays of primitive types as attribute values, using the array type.

Objects and mixed/nested arrays are not supported and will be dropped, but will eventually be supported.

Units are currently not supported and not visible in the product.

Duration Units

• nanosecond
• microsecond
• millisecond
• second
• minute
• hour
• day
• week

Information Units

• bit
• byte
• kilobyte
• kibibyte
• megabyte
• mebibyte
• gigabyte
• gibibyte
• terabyte
• tebibyte
• petabyte
• pebibyte
• exabyte
• exbibyte

Fraction Units

• ratio
• percent

Users MUST be able to attach attributes to any scope using a dedicated method (e.g., scope.setAttributes() or scope.setAttribute()).

From the user's perspective, attribute values are either primitives or objects containing:

• value: The attribute value, MUST match the specified type
• unit (optional): Unit of measurement (see Units). SDKs MAY delay adding support for units, but MUST be able to do so at a later date without a breaking change.
• type (optional): Attribute type. SDKs SHOULD NOT expose this to users if type can be reliably inferred from the value. (since 1.4.0)

Method Signature

The method SHOULD accept a dictionary/map/object where:

• Keys are attribute names (strings)
• Values are either directly values or attribute objects/dictionaries with value, and optionally unit properties
• The SDK SHOULD infer the type of the attribute at serialization time to spare users from setting a (potentially incorrect) type. Depending on platform or constraints, the SDK MAY instead also allow or require users to set the type explicitly. (since 1.4.0)

Users MUST be able to remove attributes from any scope using a dedicated method, e.g., scope.removeAttribute().

Calling scope.clear() MUST remove all attributes from the corresponding scope.

When the same attribute key exists in multiple scopes, the more specific scope's value takes precedence:

telemetry item > current scope > isolation scope > global scope

• Attributes set on the global scope MUST be applied to all logs and metrics.
• Attributes set on the isolation scope MUST be applied to all logs and metrics in that execution context.
• Attributes set on the current scope MUST be applied only while that scope is active.
• When the same attribute key exists on the telemetry item itself (log, metric), it MUST take precedence over scope attributes.

The SDK SHOULD keep the attribute format consistent with the user-set format until user-provided processing callbacks (like before_send_log) have been called. This ensures compatibility with existing callbacks and avoids unexpected changes to the attribute format. (since 1.5.0)