Show size of database file next to download link, closes #172

datasette/app.py

@@ -305,6 +305,7 @@ class Datasette:
                     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, {}))
                     }

datasette/static/app.css

@@ -286,3 +286,8 @@ a.not-underlined {
     display: inline-block;
     box-shadow: 1px 2px 8px 2px rgba(0,0,0,0.08);
 }
+
+.download-sqlite em {
+    font-style: normal;
+    font-size: 0.8em;
+}

datasette/templates/database.html

@@ -57,7 +57,7 @@
 {% endif %}
 
 {% if config.allow_download %}
-    <p>Download SQLite DB: <a href="/{{ database }}-{{ database_hash }}.db">{{ database }}.db</a></p>
+    <p class="download-sqlite">Download SQLite DB: <a href="/{{ database }}-{{ database_hash }}.db">{{ database }}.db</a> <em>{{ format_bytes(size) }}</em></p>
 {% endif %}
 
 {% include "_codemirror_foot.html" %}

datasette/utils.py

@@ -901,3 +901,15 @@ class StaticMount(click.ParamType):
         if not os.path.exists(dirpath) or not os.path.isdir(dirpath):
             self.fail("%s is not a valid directory path" % value, param, ctx)
         return path, dirpath
+
+
+def format_bytes(bytes):
+    current = float(bytes)
+    for unit in ("bytes", "KB", "MB", "GB", "TB"):
+        if current < 1024:
+            break
+        current = current / 1024
+    if unit == "bytes":
+        return "{} {}".format(int(current), unit)
+    else:
+        return "{:.1f} {}".format(current, unit)

datasette/views/base.py

@@ -19,6 +19,7 @@ from datasette.utils import (
     InterruptedError,
     InvalidSql,
     LimitedWriter,
+    format_bytes,
     is_url,
     path_from_row_pks,
     path_with_added_args,
@@ -102,6 +103,7 @@ class RenderMixin(HTTPMethodView):
                         "extra_js_urls": self._asset_urls(
                             "extra_js_urls", template, context
                         ),
+                        "format_bytes": format_bytes,
                     }
                 }
             )

datasette/views/database.py

@@ -24,6 +24,7 @@ class DatabaseView(BaseView):
         tables.sort(key=lambda t: (t["hidden"], t["name"]))
         return {
             "database": database,
+            "size": info["size"],
             "tables": tables,
             "hidden_count": len([t for t in tables if t["hidden"]]),
             "views": info["views"],

tests/test_utils.py

@@ -374,3 +374,18 @@ def test_path_with_format(path, format, extra_qs, expected):
     )
     actual = utils.path_with_format(request, format, extra_qs)
     assert expected == actual
+
+
+@pytest.mark.parametrize(
+    "bytes,expected",
+    [
+        (120, '120 bytes'),
+        (1024, '1.0 KB'),
+        (1024 * 1024, '1.0 MB'),
+        (1024 * 1024 * 1024, '1.0 GB'),
+        (1024 * 1024 * 1024 * 1.3, '1.3 GB'),
+        (1024 * 1024 * 1024 * 1024, '1.0 TB'),
+    ]
+)
+def test_format_bytes(bytes, expected):
+    assert expected == utils.format_bytes(bytes)