issues

Table actions

1 row where user = 697092 sorted by updated_at descending

✎ View and edit SQL

This data as json, CSV (advanced)

Suggested facets: created_at (date), updated_at (date)

type 1

state 1

repo 1

id node_id number title user state locked assignee milestone comments created_at updated_at ▲ closed_at author_association pull_request body repo type active_lock_reason performed_via_github_app reactions draft state_reason
1154399841 I_kwDOBm6k_c5Ezr5h 1645 Sensible `cache-control` headers for static assets, including those served by plugins curiousleo 697092 open 0   Datasette 1.0 3268330 4 2022-02-28T18:12:03Z 2022-03-08T02:59:29Z   NONE  

What I'm seeing

With default_cache_ttl = 86400, I see the following:

A table view returns Cache-control: max-age=86400:

A static asset returns no Cache-control header:

What I expected to see

I expected the static asset to return a Cache-control header indicating that this response can be cached.

Why this matters

I'm productionising a Datasette deployment right now and was looking into putting it behind a Varnish instance. I was surprised to see requests for static assets being served from Datasette rather than Varnish, this is what led me to look more closely at the response headers.

While Datasette serves those static assets pretty quickly, I don't see why Datasette should serve them. By their nature, static assets like images and JS files are very cacheable, so it should be easy to serve them from a cache like Varnish.

(Note that Varnish can easily be configured to override this header, enabling caching for static assets. But it would be better if this override was not necessary.)

Discussion

It seems clear to me that serving static assets without a Cache-control header is not ideal.

I see two options here:

A. Static assets use the same logic as table / SQL views to set the Cache-control header based on default_cache_ttl. B. An additional setting for static assets is introduced (default_static_cache_ttl, say).

 datasette 107914493 issue     
{
    "url": "https://api.github.com/repos/simonw/datasette/issues/1645/reactions",
    "total_count": 1,
    "+1": 1,
    "-1": 0,
    "laugh": 0,
    "hooray": 0,
    "confused": 0,
    "heart": 0,
    "rocket": 0,
    "eyes": 0
}
    

Advanced export

JSON shape: default, array, newline-delimited, object

CSV options: 

CREATE TABLE [issues] (
   [id] INTEGER PRIMARY KEY,
   [node_id] TEXT,
   [number] INTEGER,
   [title] TEXT,
   [user] INTEGER REFERENCES [users]([id]),
   [state] TEXT,
   [locked] INTEGER,
   [assignee] INTEGER REFERENCES [users]([id]),
   [milestone] INTEGER REFERENCES [milestones]([id]),
   [comments] INTEGER,
   [created_at] TEXT,
   [updated_at] TEXT,
   [closed_at] TEXT,
   [author_association] TEXT,
   [pull_request] TEXT,
   [body] TEXT,
   [repo] INTEGER REFERENCES [repos]([id]),
   [type] TEXT
, [active_lock_reason] TEXT, [performed_via_github_app] TEXT, [reactions] TEXT, [draft] INTEGER, [state_reason] TEXT);
CREATE INDEX [idx_issues_repo]
                ON [issues] ([repo]);
CREATE INDEX [idx_issues_milestone]
                ON [issues] ([milestone]);
CREATE INDEX [idx_issues_assignee]
                ON [issues] ([assignee]);
CREATE INDEX [idx_issues_user]
                ON [issues] ([user]);