add Meta queries, check db version on start

migrations/upend/00_initial_structure/up.sql

@@ -1,12 +1,13 @@
 CREATE TABLE meta
 (
-    id    INTEGER PRIMARY KEY AUTOINCREMENT,
+    id    INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,
     key   VARCHAR NOT NULL,
-    value VARCHAR NOT NULL
+    value VARCHAR NOT NULL,
+    UNIQUE(key)
 );
 
 INSERT INTO meta (key, value)
-VALUES ('version', '0.1.0');
+VALUES ('VERSION', '0');
 
 CREATE TABLE files
 (

src/database/inner/models.rs

@@ -3,7 +3,7 @@ use std::path::PathBuf;
 use chrono::NaiveDateTime;
 use serde::Serialize;
 
-use super::schema::{data, files};
+use super::schema::{data, files, meta};
 use crate::util::hash::Hash;
 
 #[derive(Queryable, Serialize, Clone, Debug)]
@@ -49,3 +49,11 @@ pub struct Entry {
     pub value_num: Option<f64>,
     pub immutable: bool,
 }
+
+#[derive(Queryable, Insertable, Serialize, Clone, Debug)]
+#[table_name = "meta"]
+pub struct MetaValue {
+    pub id: i32,
+    pub key: String,
+    pub value: String,
+}

src/database/inner/schema.rs

@@ -23,7 +23,7 @@ table! {
 
 table! {
     meta (id) {
-        id -> Nullable<Integer>,
+        id -> Integer,
         key -> Text,
         value -> Text,
     }

src/database/mod.rs

@@ -10,7 +10,9 @@ pub mod inner;
 pub mod lang;
 
 use crate::addressing::{Address, Addressable};
-use crate::database::constants::{IS_OF_TYPE_ATTR, TYPE_ADDR, TYPE_HAS_ATTR, TYPE_INVARIANT, LABEL_ATTR};
+use crate::database::constants::{
+    IS_OF_TYPE_ATTR, LABEL_ATTR, TYPE_ADDR, TYPE_HAS_ATTR, TYPE_INVARIANT,
+};
 use crate::database::entry::{Entry, EntryValue, ImmutableEntry};
 use crate::database::inner::models;
 use crate::database::inner::schema::data;
@@ -112,6 +114,7 @@ impl UpEndDatabase {
                 busy_timeout: Some(Duration::from_secs(30)),
             }))
             .build(manager)?;
+        trace!("Pool created.");
 
         let db = UpEndDatabase {
             pool,
@@ -120,6 +123,14 @@ impl UpEndDatabase {
         };
         let connection = db.connection().unwrap();
 
+        if !new {
+            let db_major: u64 = connection.get_meta("VERSION")?.parse()?;
+            if db_major > crate::common::PKG_VERSION_MAJOR.parse().unwrap() {
+                return Err(anyhow!("Incompatible database! Found version "));
+            }
+        }
+
+        trace!("Running initial config.");
         let enable_wal_mode = true;
         connection.execute(if enable_wal_mode {
             trace!("Enabling WAL journal mode & truncating WAL log...");
@@ -129,7 +140,7 @@ impl UpEndDatabase {
             "PRAGMA journal_mode = TRUNCATE;"
         })?;
 
-        trace!("Pool created, running migrations...");
+        trace!("Running migrations...");
 
         embedded_migrations::run_with_output(
             &db.pool.get()?,
@@ -175,6 +186,20 @@ impl UpEndConnection {
         self.conn.transaction(f)
     }
 
+    pub fn get_meta<S: AsRef<str>>(&self, key: S) -> Result<String> {
+        use crate::database::inner::schema::meta::dsl;
+        let key = key.as_ref();
+
+        debug!("Querying META:{key}");
+
+        dsl::meta
+            .filter(dsl::key.eq(key))
+            .load::<models::MetaValue>(&self.conn)?
+            .first()
+            .ok_or(anyhow!("No META \"{key}\" value found."))
+            .map(|mv| mv.value.clone())
+    }
+
     pub fn insert_file(&self, file: models::NewFile) -> Result<usize> {
         use crate::database::inner::schema::files;
 
@@ -251,7 +276,10 @@ impl UpEndConnection {
     }
 
     pub fn normalize_path(&self, path: &Path) -> Result<PathBuf> {
-        Ok(path.canonicalize()?.strip_prefix(self.vault_path.as_path())?.to_path_buf())
+        Ok(path
+            .canonicalize()?
+            .strip_prefix(self.vault_path.as_path())?
+            .to_path_buf())
     }
 
     pub fn retrieve_entry(&self, hash: Hash) -> Result<Option<Entry>> {