diff --git a/datasette/app.py b/datasette/app.py
index 453ce5c0..37b199a4 100644
--- a/datasette/app.py
+++ b/datasette/app.py
@@ -42,7 +42,7 @@ from .version import __version__
app_root = Path(__file__).parent.parent
connections = threading.local()
-
+MEMORY = object()
ConfigOption = collections.namedtuple(
"ConfigOption", ("name", "default", "help")
@@ -123,10 +123,15 @@ class Datasette:
template_dir=None,
plugins_dir=None,
static_mounts=None,
+ memory=False,
config=None,
version_note=None,
):
self.files = files
+ if not self.files:
+ self.files = [MEMORY]
+ elif memory:
+ self.files = (MEMORY,) + self.files
self.cache_headers = cache_headers
self.cors = cors
self._inspect = inspect_data
@@ -296,31 +301,40 @@ class Datasette:
self._inspect = {}
for filename in self.files:
- path = Path(filename)
- name = path.stem
- if name in self._inspect:
- raise Exception("Multiple files with same stem %s" % name)
- try:
- with sqlite3.connect(
- "file:{}?immutable=1".format(path), uri=True
- ) as conn:
- self.prepare_connection(conn)
- self._inspect[name] = {
- "hash": inspect_hash(path),
- "file": str(path),
- "size": path.stat().st_size,
- "views": inspect_views(conn),
- "tables": inspect_tables(conn, (self.metadata("databases") or {}).get(name, {}))
- }
- except sqlite3.OperationalError as e:
- if (e.args[0] == 'no such module: VirtualSpatialIndex'):
- raise click.UsageError(
- "It looks like you're trying to load a SpatiaLite"
- " database without first loading the SpatiaLite module."
- "\n\nRead more: https://datasette.readthedocs.io/en/latest/spatialite.html"
- )
- else:
- raise
+ if filename is MEMORY:
+ self._inspect[":memory:"] = {
+ "hash": "000",
+ "file": ":memory:",
+ "size": 0,
+ "views": {},
+ "tables": {},
+ }
+ else:
+ path = Path(filename)
+ name = path.stem
+ if name in self._inspect:
+ raise Exception("Multiple files with same stem %s" % name)
+ try:
+ with sqlite3.connect(
+ "file:{}?immutable=1".format(path), uri=True
+ ) as conn:
+ self.prepare_connection(conn)
+ self._inspect[name] = {
+ "hash": inspect_hash(path),
+ "file": str(path),
+ "size": path.stat().st_size,
+ "views": inspect_views(conn),
+ "tables": inspect_tables(conn, (self.metadata("databases") or {}).get(name, {}))
+ }
+ except sqlite3.OperationalError as e:
+ if (e.args[0] == 'no such module: VirtualSpatialIndex'):
+ raise click.UsageError(
+ "It looks like you're trying to load a SpatiaLite"
+ " database without first loading the SpatiaLite module."
+ "\n\nRead more: https://datasette.readthedocs.io/en/latest/spatialite.html"
+ )
+ else:
+ raise
return self._inspect
def register_custom_units(self):
@@ -403,11 +417,14 @@ class Datasette:
conn = getattr(connections, db_name, None)
if not conn:
info = self.inspect()[db_name]
- conn = sqlite3.connect(
- "file:{}?immutable=1".format(info["file"]),
- uri=True,
- check_same_thread=False,
- )
+ if info["file"] == ":memory:":
+ conn = sqlite3.connect(":memory:")
+ else:
+ conn = sqlite3.connect(
+ "file:{}?immutable=1".format(info["file"]),
+ uri=True,
+ check_same_thread=False,
+ )
self.prepare_connection(conn)
setattr(connections, db_name, conn)
diff --git a/datasette/cli.py b/datasette/cli.py
index 446456f4..6fbc9908 100644
--- a/datasette/cli.py
+++ b/datasette/cli.py
@@ -315,6 +315,9 @@ def package(
help="mountpoint:path-to-directory for serving static files",
multiple=True,
)
+@click.option(
+ "--memory", is_flag=True, help="Make :memory: database available"
+)
@click.option(
"--config",
type=Config(),
@@ -340,6 +343,7 @@ def serve(
template_dir,
plugins_dir,
static,
+ memory,
config,
version_note,
help_config,
@@ -384,6 +388,7 @@ def serve(
plugins_dir=plugins_dir,
static_mounts=static,
config=dict(config),
+ memory=memory,
version_note=version_note,
)
# Force initial hashing/table counting
diff --git a/datasette/templates/database.html b/datasette/templates/database.html
index f64d5c90..f827e584 100644
--- a/datasette/templates/database.html
+++ b/datasette/templates/database.html
@@ -19,7 +19,7 @@
{% if config.allow_sql %}
{% endif %}
@@ -56,7 +56,7 @@
{% endif %}
-{% if config.allow_download %}
+{% if config.allow_download and database != ":memory:" %}
Download SQLite DB: {{ database }}.db {{ format_bytes(size) }}
{% endif %}
diff --git a/docs/datasette-serve-help.txt b/docs/datasette-serve-help.txt
index caa00e33..65b9aceb 100644
--- a/docs/datasette-serve-help.txt
+++ b/docs/datasette-serve-help.txt
@@ -17,6 +17,7 @@ Options:
--template-dir DIRECTORY Path to directory containing custom templates
--plugins-dir DIRECTORY Path to directory containing custom plugins
--static STATIC MOUNT mountpoint:path-to-directory for serving static files
+ --memory Make :memory: database available
--config CONFIG Set config option using configname:value
datasette.readthedocs.io/en/latest/config.html
--version-note TEXT Additional note to show on /-/versions
diff --git a/tests/fixtures.py b/tests/fixtures.py
index a77a3f4a..efd85fab 100644
--- a/tests/fixtures.py
+++ b/tests/fixtures.py
@@ -65,6 +65,14 @@ def app_client():
yield from make_app_client()
+@pytest.fixture(scope="session")
+def app_client_no_files():
+ ds = Datasette([])
+ client = TestClient(ds.app().test_client)
+ client.ds = ds
+ yield client
+
+
@pytest.fixture(scope='session')
def app_client_shorter_time_limit():
yield from make_app_client(20)
diff --git a/tests/test_api.py b/tests/test_api.py
index 8cd1e94e..a6ba3f37 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -1,5 +1,6 @@
from .fixtures import ( # noqa
app_client,
+ app_client_no_files,
app_client_shorter_time_limit,
app_client_larger_cache_size,
app_client_returned_rows_matches_page_size,
@@ -368,6 +369,31 @@ def test_database_page(app_client):
}] == data['tables']
+def test_no_files_uses_memory_database(app_client_no_files):
+ response = app_client_no_files.get("/.json")
+ assert response.status == 200
+ assert {
+ ":memory:": {
+ "hash": "000",
+ "hidden_table_rows_sum": 0,
+ "hidden_tables_count": 0,
+ "name": ":memory:",
+ "path": ":memory:-000",
+ "table_rows_sum": 0,
+ "tables_count": 0,
+ "tables_more": False,
+ "tables_truncated": [],
+ "views_count": 0,
+ }
+ } == response.json
+ # Try that SQL query
+ response = app_client_no_files.get(
+ "/:memory:-0.json?sql=select+sqlite_version()&_shape=array"
+ )
+ assert 1 == len(response.json)
+ assert ["sqlite_version()"] == list(response.json[0].keys())
+
+
def test_database_page_for_database_with_dot_in_name(app_client_with_dot):
response = app_client_with_dot.get("/fixtures.dot.json")
assert 200 == response.status