Added --load-extension argument to datasette serve

Allows loading of SQLite extensions. Refs #110.

README.md

@@ -96,6 +96,7 @@ http://localhost:8001/History/downloads.jsono will return that data as JSON in a
       --max_returned_rows INTEGER  Max allowed rows to return at once - default is
                                    1000. Set to 0 to disable check entirely.
       --sql_time_limit_ms INTEGER  Max time allowed for SQL queries in ms
+      --load-extension TEXT        Path to a SQLite extension to load
       --inspect-file TEXT          Path to JSON file created using "datasette
                                    build"
       -m, --metadata FILENAME      Path to JSON file containing license/source

datasette/app.py

@@ -116,6 +116,10 @@ class BaseView(HTTPMethodView):
         conn.text_factory = lambda x: str(x, 'utf-8', 'replace')
         for name, num_args, func in self.ds.sqlite_functions:
             conn.create_function(name, num_args, func)
+        if self.ds.sqlite_extensions:
+            conn.enable_load_extension(True)
+            for extension in self.ds.sqlite_extensions:
+                conn.execute("SELECT load_extension('{}')".format(extension))
 
     async def execute(self, db_name, sql, params=None, truncate=False, custom_time_limit=None):
         """Executes sql against db_name in a thread"""
@@ -554,7 +558,7 @@ class Datasette:
     def __init__(
             self, files, num_threads=3, cache_headers=True, page_size=100,
             max_returned_rows=1000, sql_time_limit_ms=1000, cors=False,
-            inspect_data=None, metadata=None):
+            inspect_data=None, metadata=None, sqlite_extensions=None):
         self.files = files
         self.num_threads = num_threads
         self.executor = futures.ThreadPoolExecutor(
@@ -568,6 +572,7 @@ class Datasette:
         self._inspect = inspect_data
         self.metadata = metadata or {}
         self.sqlite_functions = []
+        self.sqlite_extensions = sqlite_extensions or []
 
     def inspect(self):
         if not self._inspect:

datasette/cli.py

@@ -116,9 +116,10 @@ def package(files, tag, metadata, extra_options, **extra_metadata):
 @click.option('--page_size', default=100, help='Page size - default is 100')
 @click.option('--max_returned_rows', default=1000, help='Max allowed rows to return at once - default is 1000. Set to 0 to disable check entirely.')
 @click.option('--sql_time_limit_ms', default=1000, help='Max time allowed for SQL queries in ms')
+@click.option('--load-extension', multiple=True, help="Path to a SQLite extension to load")
 @click.option('--inspect-file', help='Path to JSON file created using "datasette build"')
 @click.option('-m', '--metadata', type=click.File(mode='r'), help='Path to JSON file containing license/source metadata')
-def serve(files, host, port, debug, reload, cors, page_size, max_returned_rows, sql_time_limit_ms, inspect_file, metadata):
+def serve(files, host, port, debug, reload, cors, page_size, max_returned_rows, sql_time_limit_ms, load_extension, inspect_file, metadata):
     """Serve up specified SQLite database files with a web UI"""
     if reload:
         import hupper
@@ -142,6 +143,7 @@ def serve(files, host, port, debug, reload, cors, page_size, max_returned_rows,
         sql_time_limit_ms=sql_time_limit_ms,
         inspect_data=inspect_data,
         metadata=metadata_data,
+        sqlite_extensions=load_extension,
     )
     # Force initial hashing/table counting
     ds.inspect()

docs/auto-build.sh

@@ -0,0 +1 @@
+sphinx-autobuild . _build/html

docs/index.rst

@@ -118,6 +118,17 @@ datasette serve options
       --debug                      Enable debug mode - useful for development
       --reload                     Automatically reload if code change detected -
                                    useful for development
-      --cors                       Enable CORS by
+      --cors                       Enable CORS by serving Access-Control-Allow-
+                                   Origin: *
+      --page_size INTEGER          Page size - default is 100
+      --max_returned_rows INTEGER  Max allowed rows to return at once - default is
+                                   1000. Set to 0 to disable check entirely.
+      --sql_time_limit_ms INTEGER  Max time allowed for SQL queries in ms
+      --load-extension TEXT        Path to a SQLite extension to load
+      --inspect-file TEXT          Path to JSON file created using "datasette
+                                   build"
+      -m, --metadata FILENAME      Path to JSON file containing license/source
+                                   metadata
+      --help                       Show this message and exit.
 
 .. _Zeit Now: https://zeit.co/now