Deprecated Redis backend and added a database migration tool (untested, beware)

1 files changed, 78 insertions, 0 deletions

diff --git a/src/bin/kittybox_database_converter.rs b/src/bin/kittybox_database_converter.rs
new file mode 100644
index 0000000..ff28d49
--- /dev/null
+++ b/src/bin/kittybox_database_converter.rs
@@ -0,0 +1,78 @@
+use anyhow::{anyhow, Context};
+use redis::{self, AsyncCommands};
+use futures_util::StreamExt;
+use kittybox::database::Storage;
+use kittybox::database::FileStorage;
+use std::collections::HashMap;
+
+/// Convert from a Redis storage to a new storage new_storage.
+async fn convert_from_redis<S: Storage>(from: String, new_storage: S) -> anyhow::Result<()> {
+    let db = redis::Client::open(from).context("Failed to open the Redis connection")?;
+
+    let mut conn = db.get_async_std_connection().await.context("Failed to connect to Redis")?;
+
+    // Rebinding to convince the borrow checker we're not smuggling stuff outta scope
+    let storage = &new_storage;
+    
+    conn.hscan::<_, String>("posts").await?.map(|it| async move {
+        let json = serde_json::from_str(&it);
+        (it, json)
+    }).for_each_concurrent(8, |it| async move {
+        let (orig, res): (String, serde_json::Result<serde_json::Value>) = it.await;
+        match res {
+            Ok(json) => {
+                // XXX this assumes a trusted database that was created with Kittybox that checks for UID matching user token's prefix
+                let user = &(url::Url::parse(json["properties"]["uid"][0].as_str().unwrap()).unwrap().origin().ascii_serialization().clone() + "/");
+                if let Err(err) = storage.clone().put_post(&json, user).await {
+                    eprintln!("Error saving post: {}", err);
+                }
+            },
+            Err(err) => {
+                eprintln!("Error: {} (rejected JSON follows below on stderr)", err);
+                eprintln!("{}", orig);
+            }
+        }
+    }).await;
+
+    let mut stream: redis::AsyncIter<String> = conn.scan_match("settings_*").await?;
+    while let Some(key) = stream.next_item().await {
+        let mut conn = db.get_async_std_connection().await.context("Failed to connect to Redis")?;
+        let user = key.strip_prefix("settings_").unwrap();
+        match conn.hgetall::<&str, HashMap<String, String>>(&key).await.context(format!("Failed getting settings from key {}", key)) {
+            Ok(settings) => {
+                for (k, v) in settings.iter() {
+                    if let Err(e) = storage.set_setting(k, &user, v).await.with_context(|| format!("Failed setting {} for {}", k, user)) {
+                        eprintln!("{}", e);
+                    }
+                }
+            },
+            Err(e) => {
+                eprintln!("{}", e);
+            }
+        }
+    }
+    
+    return Ok(());
+}
+
+#[async_std::main]
+async fn main() -> anyhow::Result<()> {
+    let mut args = std::env::args();
+    args.next(); // skip argv[0]
+    let old_uri = args.next().ok_or_else(|| anyhow!("No import source is provided."))?;
+    let new_uri = args.next().ok_or_else(|| anyhow!("No import destination is provided."))?;
+
+    let storage = if new_uri.starts_with("file:") {
+        let folder = new_uri.strip_prefix("file://").unwrap();
+        let path = std::path::PathBuf::from(folder);
+        Box::new(FileStorage::new(path).await.context("Failed to construct the file storage")?)
+    } else {
+        anyhow::bail!("Cannot construct the storage abstraction for destination storage. Check the storage type?");
+    };
+    
+    if old_uri.starts_with("redis") {
+        convert_from_redis(old_uri, *storage).await?
+    }
+
+    Ok(())
+}