premix_core/
migrator.rs

1use std::error::Error;
2
3use sqlx::{Database, Executor, Pool};
4
5#[derive(Debug, Clone)]
6pub struct Migration {
7    pub version: String,
8    pub name: String,
9    pub up_sql: String,
10    pub down_sql: String,
11}
12
13#[derive(Debug, Clone, sqlx::FromRow)]
14struct AppliedMigration {
15    version: String,
16}
17
18pub struct Migrator<DB: Database> {
19    pool: Pool<DB>,
20}
21
22impl<DB: Database> Migrator<DB> {
23    pub fn new(pool: Pool<DB>) -> Self {
24        Self { pool }
25    }
26}
27
28// Specialized implementations for SQLite (Feature-gated or trait-based later)
29// For Version 1, we'll try to use generic Executor where possible,
30// but creating the migrations table often requires dialect specific SQL.
31
32#[cfg(feature = "sqlite")]
33impl Migrator<sqlx::Sqlite> {
34    pub async fn run(&self, migrations: Vec<Migration>) -> Result<(), Box<dyn Error>> {
35        let mut tx = self.pool.begin().await?;
36
37        // 1. Ensure Table Exists
38        sqlx::query(
39            "CREATE TABLE IF NOT EXISTS _premix_migrations (
40                version TEXT PRIMARY KEY,
41                name TEXT NOT NULL,
42                applied_at DATETIME DEFAULT CURRENT_TIMESTAMP
43            )",
44        )
45        .execute(&mut *tx)
46        .await?;
47
48        // 2. Get Applied Versions
49        let applied_versions: Vec<String> = sqlx::query_as::<_, AppliedMigration>(
50            "SELECT version FROM _premix_migrations ORDER BY version ASC",
51        )
52        .fetch_all(&mut *tx)
53        .await?
54        .into_iter()
55        .map(|m| m.version)
56        .collect();
57
58        // 3. Filter Pending
59        for migration in migrations {
60            if !applied_versions.contains(&migration.version) {
61                println!(
62                    "🚚 Applying migration: {} - {}",
63                    migration.version, migration.name
64                );
65
66                // Execute UP SQL
67                tx.execute(migration.up_sql.as_str()).await?;
68
69                // Record Version
70                sqlx::query("INSERT INTO _premix_migrations (version, name) VALUES (?, ?)")
71                    .bind(&migration.version)
72                    .bind(&migration.name)
73                    .execute(&mut *tx)
74                    .await?;
75            }
76        }
77
78        tx.commit().await?;
79        Ok(())
80    }
81}
82
83#[cfg(feature = "postgres")]
84impl Migrator<sqlx::Postgres> {
85    pub async fn run(&self, migrations: Vec<Migration>) -> Result<(), Box<dyn Error>> {
86        let mut tx = self.pool.begin().await?;
87
88        // 1. Ensure Table Exists
89        sqlx::query(
90            "CREATE TABLE IF NOT EXISTS _premix_migrations (
91                version TEXT PRIMARY KEY,
92                name TEXT NOT NULL,
93                applied_at TIMESTAMPTZ DEFAULT CURRENT_TIMESTAMP
94            )",
95        )
96        .execute(&mut *tx)
97        .await?;
98
99        // 2. Get Applied Versions
100        let applied_versions: Vec<String> = sqlx::query_as::<_, AppliedMigration>(
101            "SELECT version FROM _premix_migrations ORDER BY version ASC",
102        )
103        .fetch_all(&mut *tx)
104        .await?
105        .into_iter()
106        .map(|m| m.version)
107        .collect();
108
109        // 3. Filter Pending
110        for migration in migrations {
111            if !applied_versions.contains(&migration.version) {
112                println!(
113                    "🚚 Applying migration: {} - {}",
114                    migration.version, migration.name
115                );
116
117                // Execute UP SQL
118                // Note: splitting by ; might be needed for multiple statements in one file
119                // But for MVP we assume sqlx can handle the string block or user separates properly.
120                // sqlx::execute only runs the first statement for some drivers,
121                // but Executor::execute roughly maps to running the query.
122                // For safety in Postgres with multiple statements, simple Executor::execute might fail if not wrapped or specific support.
123                // We'll trust user provides valid script block for now.
124                tx.execute(migration.up_sql.as_str()).await?;
125
126                // Record Version
127                sqlx::query("INSERT INTO _premix_migrations (version, name) VALUES ($1, $2)")
128                    .bind(&migration.version)
129                    .bind(&migration.name)
130                    .execute(&mut *tx)
131                    .await?;
132            }
133        }
134
135        tx.commit().await?;
136        Ok(())
137    }
138}
premix_core/migrator.rs

premix_core/
migrator.rs
