lance-format
diff --git a/‎README.md‎
Lines changed: 37 additions & 9 deletions b/‎README.md‎
Lines changed: 37 additions & 9 deletions
diff --git a/‎python/pyproject.toml‎
Lines changed: 3 additions & 1 deletion b/‎python/pyproject.toml‎
Lines changed: 3 additions & 1 deletion
diff --git a/‎python/python/lance_context/api.py‎
Lines changed: 122 additions & 17 deletions b/‎python/python/lance_context/api.py‎
Lines changed: 122 additions & 17 deletions
diff --git a/‎python/tests/test_gcs_persistence.py‎
Lines changed: 90 additions & 0 deletions b/‎python/tests/test_gcs_persistence.py‎
Lines changed: 90 additions & 0 deletions
@@ -18,7 +18,8 @@ Key motivations inspired by the broader Lance roadmap<sup>[1](https://github.com
 - Unified schema for agent messages (`ContextRecord`) with optional embeddings and metadata.
 - Automatic versioning via Lance manifests with `checkout(version)` support.
 - Background compaction to optimize storage and read performance.
-- Remote persistence: point the store at `s3://` URIs with either AWS environment variables or explicit credentials/endpoint overrides.
+- Remote persistence on any `object_store` backend (S3, GCS, Azure Blob, ...)
+  via the generic `storage_options` dict, aligned with `lance` and `lance-graph`.
 - Python API (`lance_context.api.Context`) aligned with the Rust implementation.
 - Integration tests that exercise real persistence, image serialization, and version rollbacks.
 
@@ -68,16 +69,42 @@ ctx.checkout(first_version)
 
 print("Entries after checkout:", ctx.entries())
 
-# Store context in S3 (e.g., for MinIO/moto test endpoints)
+# Remote persistence on any object_store backend uses a generic `storage_options`
+# dict, matching the conventions used by `lance` and `lance-graph`.
+#
+# Amazon S3 (and S3-compatible endpoints like MinIO / moto):
 ctx = Context.create(
     "s3://my-bucket/context.lance",
-    aws_access_key_id="minioadmin",
-    aws_secret_access_key="minioadmin",
-    region="us-east-1",
-    endpoint_url="http://localhost:9000",
-    allow_http=True,
+    storage_options={
+        "aws_access_key_id": "minioadmin",
+        "aws_secret_access_key": "minioadmin",
+        "aws_region": "us-east-1",
+        "aws_endpoint_url": "http://localhost:9000",  # optional
+        "aws_allow_http": "true",                      # optional
+    },
+)
+# Environment variables (AWS_ACCESS_KEY_ID, ...) are picked up by lance when
+# `storage_options` isn't provided; pass overrides only when you need them.
+
+# Google Cloud Storage:
+ctx = Context.create(
+    "gs://my-bucket/context.lance",
+    storage_options={
+        # Pick one: inline service-account JSON, path to the JSON file, or ADC.
+        "google_service_account_key": service_account_json,
+        # "google_service_account_path": "/path/to/sa.json",
+        # "google_application_credentials": "/path/to/adc.json",
+    },
+)
+
+# Azure Blob Storage:
+ctx = Context.create(
+    "az://my-container/context.lance",
+    storage_options={
+        "azure_storage_account_name": "...",
+        "azure_storage_account_key": "...",
+    },
 )
-# AWS_* environment variables work too—pass overrides only when you need custom endpoints.
 
 # Background Compaction - optimize storage and read performance
 ctx = Context.create(
@@ -141,7 +168,8 @@ println!("Current version {}", store.version());
 
 We are tracking future enhancements as GitHub issues:
 
-- [Support S3-backed context stores](https://github.com/lance-format/lance-context/issues/14)
+- ~~[Support S3-backed context stores](https://github.com/lance-format/lance-context/issues/14)~~ ✅ **Implemented**
+- ~~[Support standard storage_options / GCS](https://github.com/lance-format/lance-context/issues/45)~~ ✅ **Implemented**
 - [Add relationship column for GraphRAG workflows](https://github.com/lance-format/lance-context/issues/15)
 - ~~[Background compaction for Lance fragments](https://github.com/lance-format/lance-context/issues/16)~~ ✅ **Implemented**
 
 
@@ -41,7 +41,9 @@ requires = ["maturin>=1.4"]
 build-backend = "maturin"
 
 [project.optional-dependencies]
-tests = ["pytest", "ruff", "moto[s3]", "boto3", "botocore"]
+# `moto[server]` pulls in flask + flask-cors so moto.server can be launched
+# as a subprocess for the S3 integration tests.
+tests = ["pytest", "ruff", "moto[s3,server]", "boto3", "botocore"]
 dev = ["ruff", "pyright"]
 
 [tool.ruff]
 
@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import warnings
 from datetime import datetime
 from io import BytesIO
 from typing import Any
@@ -134,40 +135,145 @@ def _normalize_search_hit(raw: dict[str, Any]) -> dict[str, Any]:
     return result
 
 
+_AWS_KWARG_MAP: dict[str, str] = {
+    "aws_access_key_id": "aws_access_key_id",
+    "aws_secret_access_key": "aws_secret_access_key",
+    "aws_session_token": "aws_session_token",
+    "region": "aws_region",
+    "endpoint_url": "aws_endpoint_url",
+}
+
+
+def _merge_storage_options(
+    storage_options: dict[str, Any] | None,
+    *,
+    aws_access_key_id: str | None,
+    aws_secret_access_key: str | None,
+    aws_session_token: str | None,
+    region: str | None,
+    endpoint_url: str | None,
+    allow_http: bool,
+) -> dict[str, Any]:
+    """Merge deprecated AWS-specific kwargs into a generic storage_options dict.
+
+    Emits a single DeprecationWarning when any AWS kwarg is used so callers
+    can migrate to the generic `storage_options` path (which works for S3,
+    GCS, Azure, and any other lance/object_store backend).
+    """
+    options: dict[str, Any] = dict(storage_options or {})
+
+    aws_kwargs = {
+        "aws_access_key_id": aws_access_key_id,
+        "aws_secret_access_key": aws_secret_access_key,
+        "aws_session_token": aws_session_token,
+        "region": region,
+        "endpoint_url": endpoint_url,
+    }
+    used = [name for name, value in aws_kwargs.items() if value is not None]
+    if allow_http:
+        used.append("allow_http")
+
+    if used:
+        warnings.warn(
+            "The AWS-specific kwargs "
+            f"({', '.join(sorted(used))}) are deprecated and will be removed in a "
+            "future release. Pass credentials via the generic "
+            "`storage_options` dict instead (e.g. "
+            "storage_options={'aws_access_key_id': ..., "
+            "'aws_secret_access_key': ...} for S3, or "
+            "storage_options={'google_service_account_key': ...} for GCS).",
+            DeprecationWarning,
+            stacklevel=3,
+        )
+
+    for kwarg_name, option_key in _AWS_KWARG_MAP.items():
+        value = aws_kwargs[kwarg_name]
+        if value is not None:
+            options.setdefault(option_key, value)
+    if allow_http:
+        options.setdefault("aws_allow_http", True)
+
+    return options
+
+
 class Context:
+    """Multimodal, versioned context store backed by Lance.
+
+    Storage backends are configured via the generic ``storage_options`` dict,
+    aligned with the conventions used by ``lance`` and ``lance-graph``. Any
+    keys understood by the underlying ``object_store`` crate are accepted.
+
+    Examples:
+        Local filesystem::
+
+            Context.create("/tmp/context.lance")
+
+        Amazon S3 (or S3-compatible endpoints like MinIO / moto)::
+
+            Context.create(
+                "s3://bucket/prefix/context.lance",
+                storage_options={
+                    "aws_access_key_id": "...",
+                    "aws_secret_access_key": "...",
+                    "aws_region": "us-east-1",
+                    "aws_endpoint_url": "http://localhost:9000",  # optional
+                    "aws_allow_http": "true",                      # optional
+                },
+            )
+
+        Google Cloud Storage::
+
+            Context.create(
+                "gs://bucket/prefix/context.lance",
+                storage_options={
+                    # Any one of these is enough; pick whatever fits your
+                    # deployment (inline JSON, file path, or ADC).
+                    "google_service_account_key": service_account_json,
+                    # "google_service_account_path": "/path/to/sa.json",
+                    # "google_application_credentials": "/path/to/adc.json",
+                },
+            )
+
+        Azure Blob Storage::
+
+            Context.create(
+                "az://container/prefix/context.lance",
+                storage_options={
+                    "azure_storage_account_name": "...",
+                    "azure_storage_account_key": "...",
+                },
+            )
+    """
+
     def __init__(
         self,
         uri: str,
         *,
         storage_options: dict[str, Any] | None = None,
+        # --- Deprecated AWS-specific shortcuts (kept for backwards compat). ---
         aws_access_key_id: str | None = None,
         aws_secret_access_key: str | None = None,
         aws_session_token: str | None = None,
         region: str | None = None,
         endpoint_url: str | None = None,
         allow_http: bool = False,
-        # Compaction configuration
+        # --- Compaction configuration. ---
         enable_background_compaction: bool = False,
         compaction_interval_secs: int = 300,
         compaction_min_fragments: int = 5,
         compaction_target_rows: int = 1_000_000,
         quiet_hours: list[tuple[int, int]] | None = None,
     ) -> None:
-        options = dict(storage_options or {})
-        if aws_access_key_id is not None:
-            options["aws_access_key_id"] = aws_access_key_id
-        if aws_secret_access_key is not None:
-            options["aws_secret_access_key"] = aws_secret_access_key
-        if aws_session_token is not None:
-            options["aws_session_token"] = aws_session_token
-        if region is not None:
-            options["aws_region"] = region
-        if endpoint_url is not None:
-            options["aws_endpoint_url"] = endpoint_url
-        if allow_http:
-            options["aws_allow_http"] = True
-
-        # Build compaction config
+        options = _merge_storage_options(
+            storage_options,
+            aws_access_key_id=aws_access_key_id,
+            aws_secret_access_key=aws_secret_access_key,
+            aws_session_token=aws_session_token,
+            region=region,
+            endpoint_url=endpoint_url,
+            allow_http=allow_http,
+        )
+
         compaction_config = {
             "enabled": enable_background_compaction,
             "check_interval_secs": compaction_interval_secs,
@@ -197,7 +303,6 @@ def create(
         region: str | None = None,
         endpoint_url: str | None = None,
         allow_http: bool = False,
-        # Compaction configuration
         enable_background_compaction: bool = False,
         compaction_interval_secs: int = 300,
         compaction_min_fragments: int = 5,
 
@@ -0,0 +1,90 @@
+"""Opt-in GCS integration tests.
+
+Skipped by default. To run locally against a real (or emulated) GCS:
+
+    # Option A: real GCS
+    export LANCE_CONTEXT_GCS_BUCKET=my-test-bucket
+    export GOOGLE_APPLICATION_CREDENTIALS=/path/to/sa.json
+    uv run pytest python/tests/test_gcs_persistence.py -v
+
+    # Option B: against fake-gcs-server or another emulator, point the
+    # relevant storage_options at the emulator endpoint (e.g. via
+    # `use_opendal=true`, `endpoint=http://...`, `allow_anonymous=true`).
+    export LANCE_CONTEXT_GCS_BUCKET=test-bucket
+    export LANCE_CONTEXT_GCS_ENDPOINT=http://127.0.0.1:4443
+    uv run pytest python/tests/test_gcs_persistence.py -v
+
+These tests intentionally do not bring up their own emulator in CI because
+there is no pure-Python GCS emulator that is both (a) maintained on modern
+Python and (b) fully compatible with the lance-io GCS backend. The S3
+suite uses moto, which has no GCS counterpart of equivalent quality.
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+import uuid
+from pathlib import Path
+
+import pytest
+
+PACKAGE_ROOT = Path(__file__).resolve().parents[2] / "python" / "python"
+if str(PACKAGE_ROOT) not in sys.path:
+    sys.path.insert(0, str(PACKAGE_ROOT))
+
+from lance_context.api import Context  # noqa: E402
+
+lance = pytest.importorskip("lance")
+
+GCS_BUCKET = os.environ.get("LANCE_CONTEXT_GCS_BUCKET")
+GCS_ENDPOINT = os.environ.get("LANCE_CONTEXT_GCS_ENDPOINT")
+GCS_SA_JSON = os.environ.get("LANCE_CONTEXT_GCS_SERVICE_ACCOUNT_KEY")
+GCS_ADC = os.environ.get("GOOGLE_APPLICATION_CREDENTIALS")
+
+_has_gcs_config = bool(GCS_BUCKET) and (
+    bool(GCS_SA_JSON) or bool(GCS_ADC) or bool(GCS_ENDPOINT)
+)
+
+pytestmark = pytest.mark.skipif(
+    not _has_gcs_config,
+    reason=(
+        "Set LANCE_CONTEXT_GCS_BUCKET plus one of "
+        "LANCE_CONTEXT_GCS_SERVICE_ACCOUNT_KEY / "
+        "GOOGLE_APPLICATION_CREDENTIALS / "
+        "LANCE_CONTEXT_GCS_ENDPOINT to run GCS integration tests."
+    ),
+)
+
+
+def _gcs_storage_options() -> dict[str, str]:
+    options: dict[str, str] = {}
+    if GCS_SA_JSON is not None:
+        options["google_service_account_key"] = GCS_SA_JSON
+    if GCS_ADC is not None:
+        options["google_application_credentials"] = GCS_ADC
+    if GCS_ENDPOINT is not None:
+        # Emulator path: OpenDAL backend supports a custom endpoint and
+        # anonymous auth, which is how fake-gcs-server is typically driven.
+        options["use_opendal"] = "true"
+        options["endpoint"] = GCS_ENDPOINT
+        options.setdefault("allow_anonymous", "true")
+    return options
+
+
+def test_gcs_round_trip_via_storage_options() -> None:
+    """End-to-end: Context.create(gs://...) with generic storage_options."""
+    assert GCS_BUCKET is not None
+    key = f"contexts/{uuid.uuid4().hex}/context.lance"
+    uri = f"gs://{GCS_BUCKET}/{key}"
+    options = _gcs_storage_options()
+
+    ctx = Context.create(uri, storage_options=options)
+
+    ctx.add("user", "gcs-hello")
+    ctx.add("assistant", "gcs-response")
+    assert ctx.entries() == 2
+
+    dataset = lance.dataset(uri, storage_options=options)
+    rows = dataset.to_table().to_pylist()
+    assert [row["text_payload"] for row in rows] == ["gcs-hello", "gcs-response"]