first messy version of filesystem state sync

dlt/common/destination/reference.py

@@ -427,6 +427,7 @@ def get_stored_schema(self) -> Optional[StorageSchemaInfo]:
 
     @abstractmethod
     def get_stored_schema_by_hash(self, version_hash: str) -> StorageSchemaInfo:
+        """retrieves the stored schema by hash"""
         pass
 
     @abstractmethod

dlt/destinations/impl/filesystem/filesystem.py

@@ -1,9 +1,12 @@
 import posixpath
 import os
 from types import TracebackType
-from typing import ClassVar, List, Type, Iterable, Set, Iterator
+from typing import ClassVar, List, Type, Iterable, Set, Iterator, Optional, Tuple
 from fsspec import AbstractFileSystem
 from contextlib import contextmanager
+from dlt.common import json, pendulum
+import base64
+import re
 
 from dlt.common import logger
 from dlt.common.schema import Schema, TSchemaTables, TTableSchema
@@ -16,6 +19,10 @@
     JobClientBase,
     FollowupJob,
     WithStagingDataset,
+    WithStateSync,
+    StorageSchemaInfo,
+    StateInfo,
+    DoNothingJob
 )
 
 from dlt.destinations.job_impl import EmptyLoadJob
@@ -87,7 +94,7 @@ def create_followup_jobs(self, final_state: TLoadJobState) -> List[NewLoadJob]:
         return jobs
 
 
-class FilesystemClient(JobClientBase, WithStagingDataset):
+class FilesystemClient(JobClientBase, WithStagingDataset, WithStateSync):
     """filesystem client storing jobs in memory"""
 
     capabilities: ClassVar[DestinationCapabilitiesContext] = capabilities()
@@ -167,15 +174,67 @@ def initialize_storage(self, truncate_tables: Iterable[str] = None) -> None:
                         " should be created previously!"
                     )
 
+    def _get_schema_file_name(self, hash: str) -> Tuple[str, str]:
+        """gets tuple of dir and fullpath for schema file for a given hash"""
+        dir = f"{self.dataset_path}/{self.schema.version_table_name}"
+        # remove all special chars from hash
+        safe_hash = "".join([c for c in hash if re.match(r"\w", c)])
+        path = f"{dir}/{self.schema.name}__{safe_hash}.jsonl"
+        return dir, path
+
     def update_stored_schema(
         self, only_tables: Iterable[str] = None, expected_update: TSchemaTables = None
     ) -> TSchemaTables:
         # create destination dirs for all tables
+        # TODO we should only create dirs for datatables
         dirs_to_create = self._get_table_dirs(only_tables or self.schema.tables.keys())
         for directory in dirs_to_create:
             self.fs_client.makedirs(directory, exist_ok=True)
+
+        # get paths
+        dir, current_path = self._get_schema_file_name("current")
+        _, hash_path = self._get_schema_file_name(self.schema.stored_version_hash)
+
+        # TODO: duplicate of weaviate implementation, should be abstracted out
+        version_info = {
+            "version_hash": self.schema.stored_version_hash,
+            "schema_name": self.schema.name,
+            "version": self.schema.version,
+            "engine_version": self.schema.ENGINE_VERSION,
+            "inserted_at": pendulum.now().isoformat(),
+            "schema": json.dumps(self.schema.to_dict()),
+        }
+
+        # we always keep tabs on what the current schema is
+        self.fs_client.makedirs(dir, exist_ok=True)  # may not be needed..
+        self.fs_client.write_text(current_path, json.dumps(version_info), "utf-8")
+        self.fs_client.write_text(hash_path, json.dumps(version_info), "utf-8")
+
         return expected_update
 
+    def get_stored_schema(self) -> Optional[StorageSchemaInfo]:
+        """Retrieves newest schema from destination storage"""
+        return self.get_stored_schema_by_hash("current")
+
+    def get_stored_schema_by_hash(self, version_hash: str) -> Optional[StorageSchemaInfo]:
+        """retrieves the stored schema by hash"""
+        _, filepath = self._get_schema_file_name(version_hash)
+        if not self.fs_client.exists(filepath):
+            return None
+        schema_info = json.loads(self.fs_client.read_text(filepath))
+        schema_info["inserted_at"] = pendulum.parse(schema_info["inserted_at"])
+        return StorageSchemaInfo(**schema_info)
+
+    def get_stored_state(self, pipeline_name: str) -> Optional[StateInfo]:
+        """Loads compressed state from destination storage"""
+        dir = f"{self.dataset_path}/{self.schema.state_table_name}"
+        current_file_name = f"{dir}/{pipeline_name}_current.jsonl"
+        if not self.fs_client.exists(current_file_name):
+            return None
+        state_json = json.loads(self.fs_client.read_text(current_file_name))
+        state_json.pop("version_hash")
+        return StateInfo(**state_json)
+
     def _get_table_dirs(self, table_names: Iterable[str]) -> Set[str]:
         """Gets unique directories where table data is stored."""
         table_dirs: Set[str] = set()
@@ -192,6 +251,11 @@ def is_storage_initialized(self) -> bool:
         return self.fs_client.isdir(self.dataset_path)  # type: ignore[no-any-return]
 
     def start_file_load(self, table: TTableSchema, file_path: str, load_id: str) -> LoadJob:
+
+        # do not load state file the regular way
+        if table["name"] == self.schema.state_table_name:
+            return DoNothingJob(file_path)
+
         cls = FollowupFilesystemJob if self.config.as_staging else LoadFilesystemJob
         return cls(
             file_path,
@@ -205,10 +269,46 @@ def restore_file_load(self, file_path: str) -> LoadJob:
         return EmptyLoadJob.from_file_path(file_path, "completed")
 
     def complete_load(self, load_id: str) -> None:
-        schema_name = self.schema.name
-        table_name = self.schema.loads_table_name
-        file_name = f"{schema_name}.{table_name}.{load_id}"
-        self.fs_client.touch(posixpath.join(self.dataset_path, file_name))
+
+        # write entry to state "table"
+        from dlt import current
+        from dlt.pipeline.state_sync import state_doc
+
+        # get the state from the current pipeline
+        pipeline = current.pipeline()
+        state = pipeline._get_state()
+        doc = state_doc(state)
+
+        # convert pendulum now to iso timestamp
+        doc["created_at"] = doc["created_at"].isoformat()
+
+        dir = f"{self.dataset_path}/{self.schema.state_table_name}"
+        safe_hash = "".join([c for c in doc["version_hash"] if re.match(r"\w", c)])
+        hash_file_name = f"{dir}/{pipeline.pipeline_name}_{safe_hash}.jsonl"
+        current_file_name = f"{dir}/{pipeline.pipeline_name}_current.jsonl"
+
+        self.fs_client.makedirs(dir, exist_ok=True)  # may not be needed..
+        self.fs_client.write_text(hash_file_name, json.dumps(doc), "utf-8")
+        self.fs_client.write_text(current_file_name, json.dumps(doc), "utf-8")
+
+        # write entry to load "table"
+        dir = f"{self.dataset_path}/{self.schema.loads_table_name}"
+        file_name = f"{self.schema.name}.{load_id}"
+        filepath = f"{dir}/{file_name}"
+
+        # TODO: this is also duplicate across all destinations. DRY this.
+        load_data = {
+            "load_id": load_id,
+            "schema_name": self.schema.name,
+            "status": 0,
+            "inserted_at": pendulum.now().isoformat(),
+            "schema_version_hash": self.schema.version_hash,
+        }
+
+        self.fs_client.makedirs(dir, exist_ok=True)  # may not be needed..
+        self.fs_client.write_text(filepath, json.dumps(load_data), "utf-8")
+
+
 
     def __enter__(self) -> "FilesystemClient":
         return self

dlt/pipeline/pipeline.py

@@ -713,7 +713,6 @@ def sync_destination(
                             remote_state["schema_names"], always_download=True
                         )
                         # TODO: we should probably wipe out pipeline here
-
                 # if we didn't full refresh schemas, get only missing schemas
                 if restored_schemas is None:
                     restored_schemas = self._get_schemas_from_destination(

dlt/pipeline/state_sync.py

@@ -115,20 +115,25 @@ def migrate_pipeline_state(
     return cast(TPipelineState, state)
 
 
-def state_resource(state: TPipelineState) -> DltResource:
-    state = copy(state)
-    state.pop("_local")
+def state_doc(state: TPipelineState) -> DictStrAny:
+    doc = copy(state)
+    doc.pop("_local")
     state_str = compress_state(state)
-    state_doc = {
+    doc = {
         "version": state["_state_version"],
         "engine_version": state["_state_engine_version"],
         "pipeline_name": state["pipeline_name"],
         "state": state_str,
         "created_at": pendulum.now(),
         "version_hash": state["_version_hash"],
     }
+    return doc
+
+
+def state_resource(state: TPipelineState) -> DltResource:
+    doc = state_doc(state)
     return dlt.resource(
-        [state_doc], name=STATE_TABLE_NAME, write_disposition="append", columns=STATE_TABLE_COLUMNS
+        [doc], name=STATE_TABLE_NAME, write_disposition="append", columns=STATE_TABLE_COLUMNS
     )
 
 

fs_testing_pipe.py

@@ -0,0 +1,20 @@
+import dlt
+import os
+
+if __name__ == "__main__":
+    os.environ["DESTINATION__FILESYSTEM__BUCKET_URL"] = "file://my_files"
+    os.environ["DATA_WRITER__DISABLE_COMPRESSION"] = "TRUE"
+
+    # resource with incremental for testing restoring of pipeline state 
+    @dlt.resource(name="my_table")
+    def my_resouce(id=dlt.sources.incremental("id")):
+        yield from [
+            {"id": 1},
+            {"id": 2},
+            {"id": 3},
+            {"id": 4},
+            {"id": 5}
+            ]
+
+    pipe = dlt.pipeline(pipeline_name="dave", destination="filesystem")
+    pipe.run(my_resouce(), table_name="my_table") #, loader_file_format="parquet")