Merge branch 'flub/send-backup'

PR: <https://github.com/deltachat/deltachat-core-rust/pull/4007>

deltachat-jsonrpc/src/api/mod.rs

@@ -22,7 +22,7 @@ use deltachat::{
     },
     provider::get_provider_info,
     qr,
-    qr_code_generator::get_securejoin_qr_svg,
+    qr_code_generator::{generate_backup_qr, get_securejoin_qr_svg},
     reaction::send_reaction,
     securejoin,
     stock_str::StockMessage,
@@ -1350,6 +1350,69 @@ impl CommandApi {
         .await
     }
 
+    /// Offers a backup for remote devices to retrieve.
+    ///
+    /// Can be cancelled by stopping the ongoing process.  Success or failure can be tracked
+    /// via the `ImexProgress` event which should either reach `1000` for success or `0` for
+    /// failure.
+    ///
+    /// This **stops IO** while it is running.
+    ///
+    /// Returns once a remote device has retrieved the backup.
+    async fn provide_backup(&self, account_id: u32) -> Result<()> {
+        let ctx = self.get_context(account_id).await?;
+        ctx.stop_io().await;
+        let provider = match imex::BackupProvider::prepare(&ctx).await {
+            Ok(provider) => provider,
+            Err(err) => {
+                ctx.start_io().await;
+                return Err(err);
+            }
+        };
+        let res = provider.await;
+        ctx.start_io().await;
+        res
+    }
+
+    /// Returns the text of the QR code for the running [`CommandApi::provide_backup`].
+    ///
+    /// This QR code text can be used in [`CommandApi::get_backup`] on a second device to
+    /// retrieve the backup and setup this second device.
+    async fn get_backup_qr(&self, account_id: u32) -> Result<String> {
+        let ctx = self.get_context(account_id).await?;
+        let qr = ctx
+            .backup_export_qr()
+            .ok_or(anyhow!("no backup being exported"))?;
+        qr::format_backup(&qr)
+    }
+
+    /// Returns the rendered QR code for the running [`CommandApi::provide_backup`].
+    ///
+    /// This QR code can be used in [`CommandApi::get_backup`] on a second device to
+    /// retrieve the backup and setup this second device.
+    ///
+    /// Returns the QR code rendered as an SVG image.
+    async fn get_backup_qr_svg(&self, account_id: u32) -> Result<String> {
+        let ctx = self.get_context(account_id).await?;
+        let qr = ctx
+            .backup_export_qr()
+            .ok_or(anyhow!("no backup being exported"))?;
+        generate_backup_qr(&ctx, &qr).await
+    }
+
+    /// Gets a backup from a remote provider.
+    ///
+    /// This retrieves the backup from a remote device over the network and imports it into
+    /// the current device.
+    ///
+    /// Can be cancelled by stopping the ongoing process.
+    async fn get_backup(&self, account_id: u32, qr_text: String) -> Result<()> {
+        let ctx = self.get_context(account_id).await?;
+        let qr = qr::check_qr(&ctx, &qr_text).await?;
+        imex::get_backup(&ctx, qr).await?;
+        Ok(())
+    }
+
     // ---------------------------------------------
     //                connectivity
     // ---------------------------------------------

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

@@ -32,6 +32,9 @@ pub enum QrObject {
     Account {
         domain: String,
     },
+    Backup {
+        ticket: String,
+    },
     WebrtcInstance {
         domain: String,
         instance_pattern: String,
@@ -126,6 +129,9 @@ impl From<Qr> for QrObject {
             }
             Qr::FprWithoutAddr { fingerprint } => QrObject::FprWithoutAddr { fingerprint },
             Qr::Account { domain } => QrObject::Account { domain },
+            Qr::Backup { ticket } => QrObject::Backup {
+                ticket: ticket.to_string(),
+            },
             Qr::WebrtcInstance {
                 domain,
                 instance_pattern,