treewide: create a common method for state initialization

Now the database objects can be uniformly created from a URI. They can
also optionally do sanity checks and one-time initialization.

4 files changed, 30 insertions, 45 deletions

diff --git a/src/database/file/mod.rs b/src/database/file/mod.rs
index f6715e1..ba8201f 100644
--- a/src/database/file/mod.rs
+++ b/src/database/file/mod.rs
@@ -197,15 +197,7 @@ fn modify_post(post: &serde_json::Value, update: MicropubUpdate) -> Result<serde
 /// A backend using a folder with JSON files as a backing store.
 /// Uses symbolic links to represent a many-to-one mapping of URLs to a post.
 pub struct FileStorage {
-    root_dir: PathBuf,
-}
-
-impl FileStorage {
-    /// Create a new storage wrapping a folder specified by root_dir.
-    pub async fn new(root_dir: PathBuf) -> Result<Self> {
-        // TODO check if the dir is writable
-        Ok(Self { root_dir })
-    }
+    pub(super) root_dir: PathBuf,
 }
 
 async fn hydrate_author<S: Storage>(
@@ -255,6 +247,10 @@ async fn hydrate_author<S: Storage>(
 
 #[async_trait]
 impl Storage for FileStorage {
+    async fn new(url: &'_ url::Url) -> Result<Self> {
+        // TODO: sanity check
+        Ok(Self { root_dir: PathBuf::from(url.path()) })
+    }
     #[tracing::instrument(skip(self))]
     async fn categories(&self, url: &str) -> Result<Vec<String>> {
         // This requires an expensive scan through the entire
diff --git a/src/database/memory.rs b/src/database/memory.rs
index 56caeec..be37fed 100644
--- a/src/database/memory.rs
+++ b/src/database/memory.rs
@@ -8,7 +8,7 @@ use tokio::sync::RwLock;
 
 use crate::database::{ErrorKind, MicropubChannel, Result, settings, Storage, StorageError};
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Default)]
 pub struct MemoryStorage {
     pub mapping: Arc<RwLock<HashMap<String, serde_json::Value>>>,
     pub channels: Arc<RwLock<HashMap<url::Url, Vec<String>>>>,
@@ -16,6 +16,10 @@ pub struct MemoryStorage {
 
 #[async_trait]
 impl Storage for MemoryStorage {
+    async fn new(_url: &url::Url) -> Result<Self> {
+        Ok(Self::default())
+    }
+
     async fn categories(&self, _url: &str) -> Result<Vec<String>> {
         unimplemented!()
     }
@@ -231,18 +235,3 @@ impl Storage for MemoryStorage {
     }
 
 }
-
-impl Default for MemoryStorage {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
-impl MemoryStorage {
-    pub fn new() -> Self {
-        Self {
-            mapping: Arc::new(RwLock::new(HashMap::new())),
-            channels: Arc::new(RwLock::new(HashMap::new())),
-        }
-    }
-}
diff --git a/src/database/mod.rs b/src/database/mod.rs
index f48b4a9..c256867 100644
--- a/src/database/mod.rs
+++ b/src/database/mod.rs
@@ -215,6 +215,8 @@ pub type Result<T> = std::result::Result<T, StorageError>;
 /// or lock the database so that write conflicts or reading half-written data should not occur.
 #[async_trait]
 pub trait Storage: std::fmt::Debug + Clone + Send + Sync {
+    /// Initialize Self from a URL, possibly performing initialization.
+    async fn new(url: &'_ url::Url) -> Result<Self>;
     /// Return the list of categories used in blog posts of a specified blog.
     async fn categories(&self, url: &str) -> Result<Vec<String>>;
 
@@ -759,11 +761,9 @@ mod tests {
             #[tracing_test::traced_test]
             async fn $func_name() {
                 let tempdir = tempfile::tempdir().expect("Failed to create tempdir");
-                let backend = super::super::FileStorage::new(
-                    tempdir.path().to_path_buf()
-                )
-                    .await
-                    .unwrap();
+                let backend = super::super::FileStorage {
+                    root_dir: tempdir.path().to_path_buf()
+                };
                 super::$func_name(backend).await
             }
         };
diff --git a/src/database/postgres/mod.rs b/src/database/postgres/mod.rs
index 7813045..0ebaffb 100644
--- a/src/database/postgres/mod.rs
+++ b/src/database/postgres/mod.rs
@@ -2,7 +2,7 @@ use std::borrow::Cow;
 use std::str::FromStr;
 
 use kittybox_util::{MicropubChannel, MentionType};
-use sqlx::{PgPool, Executor};
+use sqlx::{ConnectOptions, Executor, PgPool};
 use crate::micropub::{MicropubUpdate, MicropubPropertyDeletion};
 
 use super::settings::Setting;
@@ -36,6 +36,17 @@ pub struct PostgresStorage {
 }
 
 impl PostgresStorage {
+    /// Construct a [`PostgresStorage`] from a [`sqlx::PgPool`],
+    /// running appropriate migrations.
+    pub async fn from_pool(db: sqlx::PgPool) -> Result<Self> {
+        db.execute(sqlx::query("CREATE SCHEMA IF NOT EXISTS kittybox")).await?;
+        MIGRATOR.run(&db).await?;
+        Ok(Self { db })
+    }
+}
+
+#[async_trait::async_trait]
+impl Storage for PostgresStorage {
     /// Construct a new [`PostgresStorage`] from an URI string and run
     /// migrations on the database.
     ///
@@ -43,9 +54,9 @@ impl PostgresStorage {
     /// password from the file at the specified path. If, instead,
     /// the `PGPASS` environment variable is present, read the
     /// password from it.
-    pub async fn new(uri: &str) -> Result<Self> {
-        tracing::debug!("Postgres URL: {uri}");
-        let mut options = sqlx::postgres::PgConnectOptions::from_str(uri)?
+    async fn new(url: &'_ url::Url) -> Result<Self> {
+        tracing::debug!("Postgres URL: {url}");
+        let mut options = sqlx::postgres::PgConnectOptions::from_url(url)?
             .options([("search_path", "kittybox")]);
         if let Ok(password_file) = std::env::var("PGPASS_FILE") {
             let password = tokio::fs::read_to_string(password_file).await.unwrap();
@@ -62,17 +73,6 @@ impl PostgresStorage {
 
     }
 
-    /// Construct a [`PostgresStorage`] from a [`sqlx::PgPool`],
-    /// running appropriate migrations.
-    pub async fn from_pool(db: sqlx::PgPool) -> Result<Self> {
-        db.execute(sqlx::query("CREATE SCHEMA IF NOT EXISTS kittybox")).await?;
-        MIGRATOR.run(&db).await?;
-        Ok(Self { db })
-    }
-}
-
-#[async_trait::async_trait]
-impl Storage for PostgresStorage {
     #[tracing::instrument(skip(self))]
     async fn categories(&self, url: &str) -> Result<Vec<String>> {
         sqlx::query_scalar::<_, String>("