Replies to Fitness.app messages are annotated with an error because they do not have a payload

[ReagentX]

The message body is parsed correctly, but the messages are annotated with an error message because imessage-exporter looks for a payload that doesn't exist. This is partially related to #28.

The kIMTranscriptPluginBreadcrumbTextReceiverIdentifier data is still in the attributedBody, so it is possible to detect these messages. For example:

/// `true` if the message is from Fitness.app, else `false`
pub fn is_fitness(&self, db: &Connection) -> bool {
    matches!(self.variant(), Variant::App(CustomBalloon::Fitness)) || {
        if let Some(body) = self.attributed_body(db) {
            return String::from_utf8_lossy(&body).contains(FITNESS_RECEIVER);
        } else {
            false
        }
    }
}

Affected messages are sent by the database owner from Apple Watch as reactions to Fitness.app friends completing workouts. Apple provides some detail on how these messages get sent here.

This is a problem because these types of "replies" actually send two messages: the first is an a normal message that contains the friend's Fitness accomplishment and the second is a 2-part message that contains the chosen response and a U+FFFD char, which indicates an App payload. However, since the messages are sent separately, and the message with the U+FFFD does not have a payload, imessage-exporter emits the error.

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The first message contains an associated_message_guid that points to the second. This query returns all of the top-level Fitness messages:

SELECT * FROM message WHERE associated_message_guid NOT NULL AND associated_message_type = 3 AND balloon_bundle_id is NULL;

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imessage-exporter does a better job of Messages.app at displaying these types of messages.

From Message.app:

From imessage-exporter:

The rest of the exported data is correct, but the error should not be present.