From 9d4a77abd470af7b89e4d9116f2c9abf8a81d608 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Reynir=20Bj=C3=B6rnsson?= <reynir@reynir.dk>
Date: Wed, 24 Feb 2021 09:37:07 +0100
Subject: [PATCH] Do sqlite dance

---
 bin/migrations/m20210218.ml | 114 +++++++++++++++++++++++++++---------
 1 file changed, 87 insertions(+), 27 deletions(-)

diff --git a/bin/migrations/m20210218.ml b/bin/migrations/m20210218.ml
index de1a201..50d46dd 100644
--- a/bin/migrations/m20210218.ml
+++ b/bin/migrations/m20210218.ml
@@ -6,37 +6,83 @@ let set_version version =
     Caqti_type.unit
     (Printf.sprintf "PRAGMA user_version = %Ld" version)
 
-let alter_build_artifact =
+let new_build_artifact =
   Caqti_request.exec ~oneshot:true
     Caqti_type.unit
-    "ALTER TABLE build_artifact ADD COLUMN size INTEGER NOT NULL"
+    {| CREATE TABLE new_build_artifact (
+           id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
+           filepath TEXT NOT NULL, -- the path as in the build
+           localpath TEXT NOT NULL, -- local path to the file on disk
+           sha256 BLOB NOT NULL,
+           size INTEGER NOT NULL,
+           build INTEGER NOT NULL,
 
-let alter_build_file =
+           FOREIGN KEY(build) REFERENCES build(id),
+           UNIQUE(build, filepath)
+         )
+      |}
+
+let new_build_file =
   Caqti_request.exec ~oneshot:true
     Caqti_type.unit
-    "ALTER TABLE build_file ADD COLUMN size INTEGER NOT NULL"
+    {| CREATE TABLE new_build_file (
+           id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
+           filepath TEXT NOT NULL, -- the path as in the build
+           localpath TEXT NOT NULL, -- local path to the file on disk
+           sha256 BLOB NOT NULL,
+           size INTEGER NOT NULL,
+           build INTEGER NOT NULL,
 
-let collect_build_artifact_localpath =
+           FOREIGN KEY(build) REFERENCES build(id),
+           UNIQUE(build, filepath)
+         )
+      |}
+
+let collect_build_artifact =
   Caqti_request.collect ~oneshot:true
     Caqti_type.unit
-    Caqti_type.(tup2 int64 string)
-    "SELECT id, localpath FROM build_artifact"
+    Caqti_type.(tup3 int64 (tup3 string string octets) int64)
+    "SELECT id, filepath, localpath, sha256, build FROM build_artifact"
 
-let collect_build_file_localpath =
+let collect_build_file =
   Caqti_request.collect ~oneshot:true
     Caqti_type.unit
-    Caqti_type.(tup2 int64 string)
-    "SELECT id, localpath FROM build_file"
+    Caqti_type.(tup3 int64 (tup3 string string octets) int64)
+    "SELECT id, filepath, localpath, sha256, build FROM build_file"
 
-let set_build_artifact_size =
+let insert_new_build_artifact =
   Caqti_request.exec ~oneshot:true
-    Caqti_type.(tup2 int64 int64)
-    "UPDATE build_artifact SET size = ?2 WHERE id = ?1"
+    Caqti_type.(tup3 int64 (tup4 string string octets int64) int64)
+    {| INSERT INTO new_build_artifact (id, filepath, localpath, sha256, size, build)
+       VALUES (?, ?, ?, ?, ?, ?)
+    |}
 
-let set_build_file_size =
+let insert_new_build_file =
   Caqti_request.exec ~oneshot:true
-    Caqti_type.(tup2 int64 int64)
-    "UPDATE build_file SET size = ?2 WHERE id = ?1"
+    Caqti_type.(tup3 int64 (tup4 string string octets int64) int64)
+    {| INSERT INTO new_build_file (id, filepath, localpath, sha256, size, build)
+       VALUES (?, ?, ?, ?, ?, ?)
+    |}
+
+let drop_build_artifact =
+  Caqti_request.exec ~oneshot:true
+    Caqti_type.unit
+    "DROP TABLE build_artifact"
+
+let drop_build_file =
+  Caqti_request.exec ~oneshot:true
+    Caqti_type.unit
+    "DROP TABLE build_file"
+
+let rename_build_artifact =
+  Caqti_request.exec ~oneshot:true
+    Caqti_type.unit
+    "ALTER TABLE new_build_artifact RENAME TO build_artifact"
+
+let rename_build_file =
+  Caqti_request.exec ~oneshot:true
+    Caqti_type.unit
+    "ALTER TABLE new_build_file RENAME TO build_file"
 
 let migrate (module Db : Caqti_blocking.CONNECTION) =
   let open Rresult.R.Infix in
@@ -45,18 +91,32 @@ let migrate (module Db : Caqti_blocking.CONNECTION) =
   if application_id <> Builder_db.application_id || user_version <> old_user_version
   then Error (`Wrong_version (application_id, user_version))
   else
-    Db.exec alter_build_artifact () >>= fun () ->
-    Db.iter_s collect_build_artifact_localpath
-      (fun (id, localpath) ->
+    Db.exec new_build_artifact () >>= fun () ->
+    Db.rev_collect_list collect_build_artifact () >>= fun build_artifacts ->
+    List.fold_left
+      (fun r (id, (filepath, localpath, sha256), build) ->
+         r >>= fun () ->
          let stats = Unix.stat localpath in
-         Db.exec set_build_artifact_size (id, Int64.of_int stats.st_size))
-      ()
-    >>= fun () ->
-    Db.exec alter_build_file () >>= fun () ->
-    Db.iter_s collect_build_file_localpath
-      (fun (id, localpath) ->
+         Db.exec insert_new_build_artifact
+           (id, (filepath, localpath, sha256, Int64.of_int stats.st_size), build))
+      (Ok ())
+      build_artifacts >>= fun () ->
+    Db.exec drop_build_artifact () >>= fun () ->
+    Db.exec rename_build_artifact () >>= fun () ->
+
+    Db.exec new_build_file () >>= fun () ->
+    Db.rev_collect_list collect_build_file () >>= fun build_files ->
+    List.fold_left
+      (fun r (id, (filepath, localpath, sha256), build) ->
+         r >>= fun () ->
          let stats = Unix.stat localpath in
-         Db.exec set_build_file_size (id, Int64.of_int stats.st_size))
-      ()
+         Db.exec insert_new_build_file
+           (id, (filepath, localpath, sha256, Int64.of_int stats.st_size), build))
+      (Ok ())
+      build_files >>= fun () ->
+    Db.exec drop_build_file () >>= fun () ->
+    Db.exec rename_build_file () >>= fun () ->
+
+    Db.exec (set_version new_user_version) ()
 
 (* FIXME: rollback. Requires copying data and creating new table without size column. *)