From d1979ab05f5761782190b9f2e002400b458e593e Mon Sep 17 00:00:00 2001
From: Jef Roosens <roosensjef@gmail.com>
Date: Tue, 24 May 2022 22:48:17 +0200
Subject: [PATCH] feat(server): initial implementation of migrations

---
 src/db/db.v                            | 52 ++++++++++++++++++++++++--
 src/db/migrations/001-initial/down.sql |  3 ++
 src/db/migrations/001-initial/up.sql   | 22 +++++++++++
 src/server/server.v                    |  4 +-
 4 files changed, 77 insertions(+), 4 deletions(-)
 create mode 100644 src/db/migrations/001-initial/down.sql
 create mode 100644 src/db/migrations/001-initial/up.sql

diff --git a/src/db/db.v b/src/db/db.v
index 57b437e..9a06a03 100644
--- a/src/db/db.v
+++ b/src/db/db.v
@@ -1,19 +1,65 @@
 module db
 
 import sqlite
-import models { BuildLog, GitRepo }
 
 struct VieterDb {
 	conn sqlite.DB
 }
 
+struct MigrationVersion {
+	id      int [primary]
+	version int
+}
+
+const (
+	migrations_up   = [$embed_file('migrations/001-initial/up.sql')]
+	migrations_down = [$embed_file('migrations/001-initial/down.sql')]
+)
+
 // init initializes a database & adds the correct tables.
 pub fn init(db_path string) ?VieterDb {
 	conn := sqlite.connect(db_path)?
 
 	sql conn {
-		create table GitRepo
-		create table BuildLog
+		create table MigrationVersion
+	}
+
+	cur_version := sql conn {
+		select from MigrationVersion limit 1
+	}
+
+	// If there's no row yet, we add it here
+	if cur_version == MigrationVersion{} {
+		sql conn {
+			insert cur_version into MigrationVersion
+		}
+	}
+
+	// Apply each migration in order
+	for i in cur_version.version .. db.migrations_up.len {
+		migration := db.migrations_up[i].to_string()
+
+		version_num := i + 1
+
+		// vfmt does not like these dots
+		println('Applying migration $version_num' + '...')
+
+		// The sqlite library seems to not like it when multiple statements are
+		// passed in a single exec. Therefore, we split them & run them all
+		// separately.
+		for part in migration.split(';').map(it.trim_space()).filter(it != '') {
+			res := conn.exec_none(part)
+
+			if res != sqlite.sqlite_done {
+				return error('An error occurred while applying migration $version_num')
+			}
+		}
+
+		// The where clause doesn't really matter, as there will always only be
+		// one entry anyways.
+		sql conn {
+			update MigrationVersion set version = version_num where id > 0
+		}
 	}
 
 	return VieterDb{
diff --git a/src/db/migrations/001-initial/down.sql b/src/db/migrations/001-initial/down.sql
new file mode 100644
index 0000000..37ce683
--- /dev/null
+++ b/src/db/migrations/001-initial/down.sql
@@ -0,0 +1,3 @@
+DROP TABLE BuildLog;
+DROP TABLE GitRepoArch;
+DROP TABLE GitRepo;
diff --git a/src/db/migrations/001-initial/up.sql b/src/db/migrations/001-initial/up.sql
new file mode 100644
index 0000000..ca0aace
--- /dev/null
+++ b/src/db/migrations/001-initial/up.sql
@@ -0,0 +1,22 @@
+CREATE TABLE IF NOT EXISTS GitRepo (
+    id INTEGER PRIMARY KEY,
+    url TEXT NOT NULL,
+    branch TEXT NOT NULL,
+    repo TEXT NOT NULL,
+    schedule TEXT
+);
+
+CREATE TABLE IF NOT EXISTS GitRepoArch (
+    id INTEGER PRIMARY KEY,
+    repo_id INTEGER NOT NULL,
+    value TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS BuildLog (
+    id INTEGER PRIMARY KEY,
+    repo_id INTEGER NOT NULL,
+    start_time INTEGER NOT NULL,
+    end_time iNTEGER NOT NULL,
+    arch TEXT NOT NULL,
+    exit_code INTEGER NOT NULL
+);
diff --git a/src/server/server.v b/src/server/server.v
index 090aa76..2309ee7 100644
--- a/src/server/server.v
+++ b/src/server/server.v
@@ -68,7 +68,9 @@ pub fn server(conf Config) ? {
 	}
 
 	db_file := os.join_path_single(conf.data_dir, server.db_file_name)
-	db := db.init(db_file) or { util.exit_with_message(1, 'Failed to initialize database.') }
+	db := db.init(db_file) or {
+		util.exit_with_message(1, 'Failed to initialize database: $err.msg()')
+	}
 
 	web.run(&App{
 		logger: logger