Better tracing during the migration

Author: sandhose

crates/cli/src/commands/syn2mas.rs

@@ -80,6 +80,7 @@ enum Subcommand {
 const NUM_WRITER_CONNECTIONS: usize = 8;
 
 impl Options {
+    #[tracing::instrument("cli.syn2mas.run", skip_all)]
     #[allow(clippy::too_many_lines)]
     pub async fn run(self, figment: &Figment) -> anyhow::Result<ExitCode> {
         warn!("This version of the syn2mas tool is EXPERIMENTAL and INCOMPLETE. Do not use it, except for TESTING.");

crates/syn2mas/src/mas_writer/checks.rs

@@ -8,8 +8,10 @@
 //! This module provides safety checks to run against a MAS database before
 //! running the Synapse-to-MAS migration.
 
+use mas_storage_pg::ExecuteExt;
 use thiserror::Error;
 use thiserror_ext::ContextInto;
+use tracing::Instrument as _;
 
 use super::{is_syn2mas_in_progress, locking::LockedMasDatabase, MAS_TABLES_AFFECTED_BY_MIGRATION};
 
@@ -46,7 +48,7 @@ pub enum Error {
 /// - If any MAS tables involved in the migration are not empty.
 /// - If we can't check whether syn2mas is already in progress on this database
 ///   or not.
-#[tracing::instrument(skip_all)]
+#[tracing::instrument(name = "syn2mas.mas_pre_migration_checks", skip_all)]
 pub async fn mas_pre_migration_checks<'a>(
     mas_connection: &mut LockedMasDatabase<'a>,
 ) -> Result<(), Error> {
@@ -62,8 +64,11 @@ pub async fn mas_pre_migration_checks<'a>(
     // empty database.
 
     for &table in MAS_TABLES_AFFECTED_BY_MIGRATION {
-        let row_present = sqlx::query(&format!("SELECT 1 AS dummy FROM {table} LIMIT 1"))
+        let query = format!("SELECT 1 AS dummy FROM {table} LIMIT 1");
+        let span = tracing::info_span!("db.query", db.query.text = query);
+        let row_present = sqlx::query(&query)
             .fetch_optional(mas_connection.as_mut())
+            .instrument(span)
             .await
             .into_maybe_not_mas(table)?
             .is_some();

crates/syn2mas/src/mas_writer/constraint_pausing.rs

@@ -141,6 +141,8 @@ pub async fn restore_constraint(
         definition,
         is_fk: _,
     } = &constraint;
+    info!("rebuilding constraint {name}");
+
     sqlx::query(&format!(
         "ALTER TABLE {table_name} ADD CONSTRAINT {name} {definition};"
     ))

crates/syn2mas/src/mas_writer/mod.rs

@@ -397,7 +397,7 @@ impl<'conn> MasWriter<'conn> {
     ///
     /// - If the database connection experiences an error.
     #[allow(clippy::missing_panics_doc)] // not real
-    #[tracing::instrument(skip_all)]
+    #[tracing::instrument(name = "syn2mas.mas_writer.new", skip_all)]
     pub async fn new(
         mut conn: LockedMasDatabase<'conn>,
         index_restore_conn: PgConnection,
@@ -526,7 +526,7 @@ impl<'conn> MasWriter<'conn> {
         })
     }
 
-    #[tracing::instrument(skip_all)]
+    #[tracing::instrument(name = "syn2mas.mas_writer.restore_task", skip_all)]
     fn restore_task(
         mut conn: PgConnection,
     ) -> (
@@ -551,9 +551,10 @@ impl<'conn> MasWriter<'conn> {
                     }
                 }
 
+                tracing::info!("Restoring task done");
                 Ok(())
             }
-            .instrument(tracing::info_span!("restore")),
+            .instrument(tracing::info_span!("syn2mas.mas_writer.restore_loop")),
         );
 
         (constraint_restore_tx, index_restore_tx, restorer_task)