implemented 0.db as admin database architecture + updated test file

src/admin_meta.rs

@@ -0,0 +1,361 @@
+use std::path::PathBuf;
+use std::sync::{Arc, OnceLock, Mutex, RwLock};
+use std::collections::HashMap;
+
+use crate::error::DBError;
+use crate::options;
+use crate::rpc::Permissions;
+use crate::storage::Storage;
+use crate::storage_sled::SledStorage;
+use crate::storage_trait::StorageBackend;
+
+// Key builders
+fn k_admin_next_id() -> &'static str {
+    "admin:next_id"
+}
+fn k_admin_dbs() -> &'static str {
+    "admin:dbs"
+}
+fn k_meta_db(id: u64) -> String {
+    format!("meta:db:{}", id)
+}
+fn k_meta_db_keys(id: u64) -> String {
+    format!("meta:db:{}:keys", id)
+}
+fn k_meta_db_enc(id: u64) -> String {
+    format!("meta:db:{}:enc", id)
+}
+
+// Global cache of admin DB 0 handles per base_dir to avoid sled/reDB file-lock contention
+// and to correctly isolate different test instances with distinct directories.
+static ADMIN_STORAGES: OnceLock<RwLock<HashMap<String, Arc<dyn StorageBackend>>>> = OnceLock::new();
+
+// Global registry for data DB storages to avoid double-open across process.
+static DATA_STORAGES: OnceLock<RwLock<HashMap<u64, Arc<dyn StorageBackend>>>> = OnceLock::new();
+static DATA_INIT_LOCK: Mutex<()> = Mutex::new(());
+
+fn init_admin_storage(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+) -> Result<Arc<dyn StorageBackend>, DBError> {
+    let db_file = PathBuf::from(base_dir).join("0.db");
+    if let Some(parent_dir) = db_file.parent() {
+        std::fs::create_dir_all(parent_dir).map_err(|e| {
+            DBError(format!("Failed to create directory {}: {}", parent_dir.display(), e))
+        })?;
+    }
+    let storage: Arc<dyn StorageBackend> = match backend {
+        options::BackendType::Redb => Arc::new(Storage::new(&db_file, true, Some(admin_secret))?),
+        options::BackendType::Sled => Arc::new(SledStorage::new(&db_file, true, Some(admin_secret))?),
+    };
+    Ok(storage)
+}
+
+// Get or initialize a cached handle to admin DB 0 per base_dir (thread-safe, no double-open race)
+pub fn open_admin_storage(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+) -> Result<Arc<dyn StorageBackend>, DBError> {
+    let map = ADMIN_STORAGES.get_or_init(|| RwLock::new(HashMap::new()));
+    // Fast path
+    if let Some(st) = map.read().unwrap().get(base_dir) {
+        return Ok(st.clone());
+    }
+    // Slow path with write lock
+    {
+        let mut w = map.write().unwrap();
+        if let Some(st) = w.get(base_dir) {
+            return Ok(st.clone());
+        }
+        let st = init_admin_storage(base_dir, backend, admin_secret)?;
+        w.insert(base_dir.to_string(), st.clone());
+        return Ok(st);
+    }
+}
+
+// Ensure admin structures exist in encrypted DB 0
+pub fn ensure_bootstrap(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+) -> Result<(), DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+
+    // Initialize next id if missing
+    if !admin.exists(k_admin_next_id())? {
+        admin.set(k_admin_next_id().to_string(), "1".to_string())?;
+    }
+    // admin:dbs is a hash; it's fine if it doesn't exist (hlen -> 0)
+    Ok(())
+}
+
+// Get or initialize a shared handle to a data DB (> 0), avoiding double-open across subsystems
+pub fn open_data_storage(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+) -> Result<Arc<dyn StorageBackend>, DBError> {
+    if id == 0 {
+        return open_admin_storage(base_dir, backend, admin_secret);
+    }
+
+    // Validate existence in admin metadata
+    if !db_exists(base_dir, backend.clone(), admin_secret, id)? {
+        return Err(DBError(format!(
+            "Cannot open database instance {}, as that database instance does not exist.",
+            id
+        )));
+    }
+
+    let map = DATA_STORAGES.get_or_init(|| RwLock::new(HashMap::new()));
+    // Fast path
+    if let Some(st) = map.read().unwrap().get(&id) {
+        return Ok(st.clone());
+    }
+
+    // Slow path with init lock
+    let _guard = DATA_INIT_LOCK.lock().unwrap();
+    if let Some(st) = map.read().unwrap().get(&id) {
+        return Ok(st.clone());
+    }
+
+    // Determine per-db encryption
+    let enc = get_enc_key(base_dir, backend.clone(), admin_secret, id)?;
+    let should_encrypt = enc.is_some();
+
+    // Build database file path and ensure parent dir exists
+    let db_file = PathBuf::from(base_dir).join(format!("{}.db", id));
+    if let Some(parent_dir) = db_file.parent() {
+        std::fs::create_dir_all(parent_dir).map_err(|e| {
+            DBError(format!("Failed to create directory {}: {}", parent_dir.display(), e))
+        })?;
+    }
+
+    // Open storage
+    let storage: Arc<dyn StorageBackend> = match backend {
+        options::BackendType::Redb => Arc::new(Storage::new(&db_file, should_encrypt, enc.as_deref())?),
+        options::BackendType::Sled => Arc::new(SledStorage::new(&db_file, should_encrypt, enc.as_deref())?),
+    };
+
+    // Publish to registry
+    map.write().unwrap().insert(id, storage.clone());
+    Ok(storage)
+}
+
+// Allocate the next DB id and persist new pointer
+pub fn allocate_next_id(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+) -> Result<u64, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let cur = admin
+        .get(k_admin_next_id())?
+        .unwrap_or_else(|| "1".to_string());
+    let id: u64 = cur.parse().unwrap_or(1);
+    let next = id.checked_add(1).ok_or_else(|| DBError("next_id overflow".into()))?;
+    admin.set(k_admin_next_id().to_string(), next.to_string())?;
+
+    // Register into admin:dbs set/hash
+    let _ = admin.hset(k_admin_dbs(), vec![(id.to_string(), "1".to_string())])?;
+
+    // Default meta for the new db: public true
+    let meta_key = k_meta_db(id);
+    let _ = admin.hset(&meta_key, vec![("public".to_string(), "true".to_string())])?;
+
+    Ok(id)
+}
+
+// Check existence of a db id in admin:dbs
+pub fn db_exists(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+) -> Result<bool, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    Ok(admin.hexists(k_admin_dbs(), &id.to_string())?)
+}
+
+// Get per-db encryption key, if any
+pub fn get_enc_key(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+) -> Result<Option<String>, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    admin.get(&k_meta_db_enc(id))
+}
+
+// Set per-db encryption key (called during create)
+pub fn set_enc_key(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+    key: &str,
+) -> Result<(), DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    admin.set(k_meta_db_enc(id), key.to_string())
+}
+
+// Set database public flag
+pub fn set_database_public(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+    public: bool,
+) -> Result<(), DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let mk = k_meta_db(id);
+    let _ = admin.hset(&mk, vec![("public".to_string(), public.to_string())])?;
+    Ok(())
+}
+
+// Internal: load public flag; default to true when meta missing
+fn load_public(
+    admin: &Arc<dyn StorageBackend>,
+    id: u64,
+) -> Result<bool, DBError> {
+    let mk = k_meta_db(id);
+    match admin.hget(&mk, "public")? {
+        Some(v) => Ok(v == "true"),
+        None => Ok(true),
+    }
+}
+
+// Add access key for db (value format: "Read:ts" or "ReadWrite:ts")
+pub fn add_access_key(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+    key_plain: &str,
+    perms: Permissions,
+) -> Result<(), DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let hash = crate::rpc::hash_key(key_plain);
+    let v = match perms {
+        Permissions::Read => format!("Read:{}", now_secs()),
+        Permissions::ReadWrite => format!("ReadWrite:{}", now_secs()),
+    };
+    let _ = admin.hset(&k_meta_db_keys(id), vec![(hash, v)])?;
+    Ok(())
+}
+
+// Delete access key by hash
+pub fn delete_access_key(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+    key_hash: &str,
+) -> Result<bool, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let n = admin.hdel(&k_meta_db_keys(id), vec![key_hash.to_string()])?;
+    Ok(n > 0)
+}
+
+// List access keys, returning (hash, perms, created_at_secs)
+pub fn list_access_keys(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+) -> Result<Vec<(String, Permissions, u64)>, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let pairs = admin.hgetall(&k_meta_db_keys(id))?;
+    let mut out = Vec::new();
+    for (hash, val) in pairs {
+        let (perm, ts) = parse_perm_value(&val);
+        out.push((hash, perm, ts));
+    }
+    Ok(out)
+}
+
+// Verify access permission for db id with optional key
+// Returns:
+// - Ok(Some(Permissions)) when access is allowed
+// - Ok(None) when not allowed or db missing (caller can distinguish by calling db_exists)
+pub fn verify_access(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+    id: u64,
+    key_opt: Option<&str>,
+) -> Result<Option<Permissions>, DBError> {
+    // Admin DB 0: require exact admin_secret
+    if id == 0 {
+        if let Some(k) = key_opt {
+            if k == admin_secret {
+                return Ok(Some(Permissions::ReadWrite));
+            }
+        }
+        return Ok(None);
+    }
+
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    if !admin.hexists(k_admin_dbs(), &id.to_string())? {
+        return Ok(None);
+    }
+
+    // Public?
+    if load_public(&admin, id)? {
+        return Ok(Some(Permissions::ReadWrite));
+    }
+
+    // Private: require key and verify
+    if let Some(k) = key_opt {
+        let hash = crate::rpc::hash_key(k);
+        if let Some(v) = admin.hget(&k_meta_db_keys(id), &hash)? {
+            let (perm, _ts) = parse_perm_value(&v);
+            return Ok(Some(perm));
+        }
+    }
+    Ok(None)
+}
+
+// Enumerate all db ids
+pub fn list_dbs(
+    base_dir: &str,
+    backend: options::BackendType,
+    admin_secret: &str,
+) -> Result<Vec<u64>, DBError> {
+    let admin = open_admin_storage(base_dir, backend, admin_secret)?;
+    let ids = admin.hkeys(k_admin_dbs())?;
+    let mut out = Vec::new();
+    for s in ids {
+        if let Ok(v) = s.parse() {
+            out.push(v);
+        }
+    }
+    Ok(out)
+}
+
+// Helper: parse permission value "Read:ts" or "ReadWrite:ts"
+fn parse_perm_value(v: &str) -> (Permissions, u64) {
+    let mut parts = v.split(':');
+    let p = parts.next().unwrap_or("Read");
+    let ts = parts
+        .next()
+        .and_then(|s| s.parse().ok())
+        .unwrap_or(0u64);
+    let perm = match p {
+        "ReadWrite" => Permissions::ReadWrite,
+        _ => Permissions::Read,
+    };
+    (perm, ts)
+}
+
+fn now_secs() -> u64 {
+    use std::time::{SystemTime, UNIX_EPOCH};
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}