Fix: snappy downloader

stackslib/src/burnchains/burnchain.rs

@@ -702,6 +702,10 @@ impl Burnchain {
     }
 
     pub fn get_burnchaindb_path(&self) -> String {
+        if self.working_dir.as_str() == ":memory:" {
+            return ":memory:".to_string();
+        }
+
         let chainstate_dir = Burnchain::get_chainstate_path_str(&self.working_dir);
         let mut db_pathbuf = PathBuf::from(&chainstate_dir);
         db_pathbuf.push("burnchain.sqlite");
@@ -743,12 +747,14 @@ impl Burnchain {
     /// Open just the burnchain database
     pub fn open_burnchain_db(&self, readwrite: bool) -> Result<BurnchainDB, burnchain_error> {
         let burnchain_db_path = self.get_burnchaindb_path();
-        if let Err(e) = fs::metadata(&burnchain_db_path) {
-            warn!(
-                "Failed to stat burnchain DB path '{}': {:?}",
-                &burnchain_db_path, &e
-            );
-            return Err(burnchain_error::DBError(db_error::NoDBError));
+        if burnchain_db_path != ":memory:" {
+            if let Err(e) = fs::metadata(&burnchain_db_path) {
+                warn!(
+                    "Failed to stat burnchain DB path '{}': {:?}",
+                    &burnchain_db_path, &e
+                );
+                return Err(burnchain_error::DBError(db_error::NoDBError));
+            }
         }
         test_debug!(
             "Open burnchain DB at {} (rw? {})",

stackslib/src/burnchains/db.rs

@@ -1000,33 +1000,38 @@ impl BurnchainDB {
         readwrite: bool,
     ) -> Result<BurnchainDB, BurnchainError> {
         let mut create_flag = false;
-        let open_flags = match fs::metadata(path) {
-            Err(e) => {
-                if e.kind() == io::ErrorKind::NotFound {
-                    // need to create
-                    if readwrite {
-                        create_flag = true;
-                        let ppath = Path::new(path);
-                        let pparent_path = ppath
-                            .parent()
-                            .unwrap_or_else(|| panic!("BUG: no parent of '{}'", path));
-                        fs::create_dir_all(&pparent_path)
-                            .map_err(|e| BurnchainError::from(DBError::IOError(e)))?;
-
-                        OpenFlags::SQLITE_OPEN_READ_WRITE | OpenFlags::SQLITE_OPEN_CREATE
+        let open_flags = if path == ":memory:" {
+            create_flag = true;
+            OpenFlags::SQLITE_OPEN_READ_WRITE | OpenFlags::SQLITE_OPEN_CREATE
+        } else {
+            match fs::metadata(path) {
+                Err(e) => {
+                    if e.kind() == io::ErrorKind::NotFound {
+                        // need to create
+                        if readwrite {
+                            create_flag = true;
+                            let ppath = Path::new(path);
+                            let pparent_path = ppath
+                                .parent()
+                                .unwrap_or_else(|| panic!("BUG: no parent of '{}'", path));
+                            fs::create_dir_all(&pparent_path)
+                                .map_err(|e| BurnchainError::from(DBError::IOError(e)))?;
+
+                            OpenFlags::SQLITE_OPEN_READ_WRITE | OpenFlags::SQLITE_OPEN_CREATE
+                        } else {
+                            return Err(BurnchainError::from(DBError::NoDBError));
+                        }
                     } else {
-                        return Err(BurnchainError::from(DBError::NoDBError));
+                        return Err(BurnchainError::from(DBError::IOError(e)));
                     }
-                } else {
-                    return Err(BurnchainError::from(DBError::IOError(e)));
                 }
-            }
-            Ok(_md) => {
-                // can just open
-                if readwrite {
-                    OpenFlags::SQLITE_OPEN_READ_WRITE
-                } else {
-                    OpenFlags::SQLITE_OPEN_READ_ONLY
+                Ok(_md) => {
+                    // can just open
+                    if readwrite {
+                        OpenFlags::SQLITE_OPEN_READ_WRITE
+                    } else {
+                        OpenFlags::SQLITE_OPEN_READ_ONLY
+                    }
                 }
             }
         };
@@ -1089,7 +1094,7 @@ impl BurnchainDB {
         let conn = sqlite_open(path, open_flags, true)?;
         let mut db = BurnchainDB { conn };
 
-        if readwrite {
+        if readwrite || path == ":memory:" {
             db.add_indexes()?;
         }
         Ok(db)

stackslib/src/chainstate/nakamoto/mod.rs

@@ -328,7 +328,7 @@ pub trait StacksDBIndexed {
     fn get(&mut self, tip: &StacksBlockId, key: &str) -> Result<Option<String>, DBError>;
     fn sqlite(&self) -> &Connection;
 
-    /// Get the ancestor block hash given a height
+    /// Get the ancestor block hash given a coinbase height
     fn get_ancestor_block_id(
         &mut self,
         coinbase_height: u64,