feat(storage): add dump storage table to file utility

crates/papyrus_storage/src/lib.rs

@@ -52,6 +52,7 @@
 pub mod base_layer;
 pub mod body;
 pub mod compiled_class;
+pub mod utils;
 // TODO(yair): Make the compression_utils module pub(crate) or extract it from the crate.
 #[doc(hidden)]
 pub mod compression_utils;
@@ -415,6 +416,10 @@ pub enum StorageError {
     CompiledClassReWrite { class_hash: ClassHash },
     #[error("The table {table_name} is unused under the {storage_scope:?} storage scope.")]
     ScopeError { table_name: String, storage_scope: StorageScope },
+    #[error(transparent)]
+    IOError(#[from] std::io::Error),
+    #[error(transparent)]
+    SerdeError(#[from] serde_json::Error),
 }
 
 /// A type alias that maps to std::result::Result<T, StorageError>.

crates/papyrus_storage/src/utils.rs

@@ -0,0 +1,48 @@
+//! module for external utils, such as dumping a storage table to a file
+#[cfg(test)]
+#[path = "utils_test.rs"]
+mod utils_test;
+
+use std::fs::File;
+use std::io::{BufWriter, Write};
+
+use crate::db::serialization::StorageSerde;
+use crate::db::{DbIter, TableIdentifier, RO};
+use crate::{open_storage, StorageConfig, StorageResult, StorageTxn};
+
+/// dumps a table from the storage to a file in JSON format
+fn dump_table_to_file<K, V>(
+    txn: &StorageTxn<'_, RO>,
+    table_id: &TableIdentifier<K, V>,
+    file_path: &str,
+) -> StorageResult<()>
+where
+    K: StorageSerde + serde::Serialize,
+    V: StorageSerde + serde::Serialize,
+{
+    let table_handle = txn.txn.open_table(table_id)?;
+    let mut cursor = table_handle.cursor(&txn.txn)?;
+    let iter = DbIter::new(&mut cursor);
+    let file = File::create(file_path)?;
+    let mut writer = BufWriter::new(file);
+    writer.write_all(b"[")?;
+    let mut first = true;
+    for data in iter {
+        if !first {
+            writer.write_all(b",")?;
+        }
+        serde_json::to_writer(&mut writer, &data.unwrap())?;
+        first = false;
+    }
+    writer.write_all(b"]")?;
+    Ok(())
+}
+
+/// dumps the declared classes table from the storage to a file
+pub fn dump_declared_classes_table_to_file(file_path: &str) -> StorageResult<()> {
+    let storage_config = StorageConfig::default();
+    let (storage_reader, _) = open_storage(storage_config.clone())?;
+    let txn = storage_reader.begin_ro_txn()?;
+    dump_table_to_file(&txn, &txn.tables.declared_classes, file_path)?;
+    Ok(())
+}

crates/papyrus_storage/src/utils_test.rs

@@ -0,0 +1,65 @@
+use std::collections::HashMap;
+use std::fs;
+
+use indexmap::indexmap;
+use starknet_api::block::BlockNumber;
+use starknet_api::core::{ClassHash, CompiledClassHash};
+use starknet_api::hash::{StarkFelt, StarkHash};
+use starknet_api::state::{ContractClass, StateDiff};
+
+use super::dump_table_to_file;
+use crate::state::StateStorageWriter;
+use crate::test_utils::get_test_storage;
+
+#[test]
+fn test_dump_table_to_file() {
+    let file_path = "tmp_test_dump_declared_classes_table.json";
+    let declared_class1 = (
+        ClassHash(1u128.into()),
+        ContractClass {
+            sierra_program: vec![StarkFelt::ONE, StarkFelt::TWO],
+            entry_point_by_type: HashMap::new(),
+            abi: "".to_string(),
+        },
+    );
+    let declared_class2 = (
+        ClassHash(2u128.into()),
+        ContractClass {
+            sierra_program: vec![StarkFelt::THREE, StarkFelt::ZERO],
+            entry_point_by_type: HashMap::new(),
+            abi: "".to_string(),
+        },
+    );
+    let compiled_class_hash = CompiledClassHash(StarkHash::default());
+    let declared_classes = vec![declared_class1.clone(), declared_class2.clone()];
+    let declared_classes_for_append_state = indexmap!(
+        declared_class1.0 =>
+        (compiled_class_hash, declared_class1.1.clone()),
+        declared_class2.0 =>
+        (compiled_class_hash, declared_class2.1.clone()),
+    );
+
+    let ((reader, mut writer), _temp_dir) = get_test_storage();
+    let txn = writer.begin_rw_txn().unwrap();
+    txn.append_state_diff(
+        BlockNumber(0),
+        StateDiff {
+            deployed_contracts: indexmap!(),
+            storage_diffs: indexmap!(),
+            declared_classes: declared_classes_for_append_state,
+            deprecated_declared_classes: indexmap!(),
+            nonces: indexmap!(),
+            replaced_classes: indexmap!(),
+        },
+        indexmap!(),
+    )
+    .unwrap()
+    .commit()
+    .unwrap();
+
+    let txn = reader.begin_ro_txn().unwrap();
+    dump_table_to_file(&txn, &txn.tables.declared_classes, file_path).unwrap();
+    let file_content = fs::read_to_string(file_path).unwrap();
+    let _ = fs::remove_file(file_path);
+    assert_eq!(file_content, serde_json::to_string(&declared_classes).unwrap());
+}