issue_comments

The plugin works. I'm going to implement one last feature for it:

• https://github.com/simonw/datasette-hashed-urls/issues/3

Then I can remove hashed URL mode in a separate issue.

I shipped the first version of this: https://github.com/simonw/datasette-hashed-urls

Next step: test it with a live demo: - https://github.com/simonw/datasette-hashed-urls/issues/2

It would be neat if the plugin could spot old-style hyphen hash URLs (maybe on 404) and redirect those too.

I'm now convinced this is feasible enough that it's worth doing in time for Datasette 1.0.

This seems to do the job: python @hookimpl def startup(datasette): for name, database in datasette.databases.items(): if database.hash: new_name = "{}_{}".format(name, database.hash[:7]) del datasette.databases[name] datasette.databases[new_name] = database Would have to teach the rest of the plugin to split on _ and to only redirect if the user seems to be hitting the URL for an old hash after which Datasette has been restarted with an updated database.

Maybe the plugin should interfere with datasette.databases on startup and change the registered name for each one?

Built a prototype of that plugin: ```python from datasette import hookimpl from functools import wraps

@hookimpl def asgi_wrapper(datasette): def wrap_with_hashed_urls(app): @wraps(app) async def hashed_urls(scope, receive, send): # Only triggers on pages with a path not starting in /-/ # and where the first page component matches a database name if scope.get("type") != "http": await app(scope, receive, send) return path = scope["path"].lstrip("/") if not path or path.startswith("-/"): await app(scope, receive, send) return potential_database = path.split("/")[0] # It may or may not be already dbname~hash if "~" in potential_database: db_name, hash = potential_database.split("~", 1) else: db_name = potential_database hash = "" # Is db_name a database we have a hash for? try: db = datasette.get_database(db_name) except KeyError: await app(scope, receive, send) return

        if db.hash is not None:
            # TODO: make sure db.hash is documented
            if db.hash[:7] != hash:
                # Send a redirect
                path_bits = path.split("/")
                new_path = "/" + "/".join(["{}-{}".format(db_name, db.hash[:7])] + path_bits[1:])
                if scope.get("query_string"):
                    new_path += "?" + scope["query_string"].decode("latin-1")

                await send({
                    "type": "http.response.start",
                    "status": 302,
                    "headers": [
                        [b"location", new_path.encode("latin1")]
                    ],
                })
                await send({"type": "http.response.body", "body": b""})
                return
            else:
                # Add a far-future cache header
                async def wrapped_send(event):
                    if event["type"] == "http.response.start":
                        original_headers = event.get("headers") or []
                        event = {
                            "type": event["type"],
                            "status": event["status"],
                            "headers": original_headers + [
                                [b"Cache-Control", b"max-age=31536000"]
                            ],
                        }
                    await send(event)

                await app(scope, receive, wrapped_send)
                return

        await app(scope, receive, send)
    return hashed_urls
return wrap_with_hashed_urls

``` One catch: it doesn't affect the way URLs are generated - so every internal link within Datasette links to the non-hash version and then triggers a 302 redirect to the hashed version.

This needs to take into account the changes made here: - #1439

In the new encoding scheme, - has a special meaning in a table name: https://docs.datasette.io/en/latest/internals.html#dash-encoding

I think ~ is the right character to use to separate a database name from its hash. ~ should be a URL safe character according to Python's implementation of percent-encoding, see comment here: https://github.com/simonw/datasette/blob/c5791156d92615f25696ba93dae5bb2dcc192c98/datasette/utils/init.py#L1146-L1152

So the plugin could check for dbname~hash and react based on that.

Now that I'm looking at refactoring how views work in #878 it's clear that the gnarliest, most convoluted code I need to deal with relates to this old feature.

I'm going to remove it entirely. Any performance enhancement or provides can be achieved just as well by using regular URLs and a caching proxy.

I may provide a 404 handling plugin that attempts to rewrite old URLs that used this mechanism, but I won't do any more than that.