add verified-by api to jsonrpc (#3946)

also refactor it so that it is not a static method anymore
(would have resulted in two load-Contact-from-db-calls in jsonrpc)

deltachat-jsonrpc/src/api/types/contact.rs

@@ -20,6 +20,10 @@ pub struct ContactObject {
     name_and_addr: String,
     is_blocked: bool,
     is_verified: bool,
+    /// the address that verified this contact
+    verifier_addr: Option<String>,
+    /// the id of the contact that verified this contact
+    verifier_id: Option<u32>,
     /// the contact's last seen timestamp
     last_seen: i64,
     was_seen_recently: bool,
@@ -36,6 +40,18 @@ impl ContactObject {
         };
         let is_verified = contact.is_verified(context).await? == VerifiedStatus::BidirectVerified;
 
+        let (verifier_addr, verifier_id) = if is_verified {
+            (
+                contact.get_verifier_addr(context).await?,
+                contact
+                    .get_verifier_id(context)
+                    .await?
+                    .map(|contact_id| contact_id.to_u32()),
+            )
+        } else {
+            (None, None)
+        };
+
         Ok(ContactObject {
             address: contact.get_addr().to_owned(),
             color: color_int_to_hex_string(contact.get_color()),
@@ -48,6 +64,8 @@ impl ContactObject {
             name_and_addr: contact.get_name_n_addr(),
             is_blocked: contact.is_blocked(),
             is_verified,
+            verifier_addr,
+            verifier_id,
             last_seen: contact.last_seen(),
             was_seen_recently: contact.was_seen_recently(),
         })