Refs #622

I deployed https://github-to-sqlite-releases-j7hipcg4aq-uc.a.run.app/ by running this: ```

!/bin/bash

Fetch repos for simonw and dogsheep

github-to-sqlite repos github.db simonw dogsheep -a auth.json

Fetch releases for the repos tagged 'datasette-io'

sqlite-utils github.db " select full_name from repos where rowid in ( select repos.rowid from repos, json_each(repos.topics) j where j.value = 'datasette-io' )" --csv --no-headers | while read repo; do github-to-sqlite releases \ github.db $(echo $repo | tr -d '\r') \ -a auth.json; sleep 2; done; And then deploying using this: $ datasette publish cloudrun github.db \ --title "github-to-sqlite releases demo" \ --about_url="https://github.com/simonw/github-to-sqlite" \ --about='github-to-sqlite' \ --install=datasette-render-markdown \ --install=datasette-json-html \ --service=github-to-sqlite-releases ``` This should happen automatically for every release. I can run it once a day in Circle CI to keep the demo database up-to-date.

This thread here is illuminating: https://stackoverflow.com/questions/3634984/insert-if-not-exists-else-update

The term UPSERT in SQLite has a specific meaning as-of 3.24.0 (2018-06-04): https://www.sqlite.org/lang_UPSERT.html

It means "behave as an UPDATE or a no-op if the INSERT would violate a uniqueness constraint". The syntax in 3.24.0+ looks like this (confusingly it does not use the term "upsert"): sql INSERT INTO phonebook(name,phonenumber) VALUES('Alice','704-555-1212') ON CONFLICT(name) DO UPDATE SET phonenumber=excluded.phonenumber Here's the problem: the sqlite-utils .upsert() and .upsert_all() methods don't do this. They use the following SQL:

sql INSERT OR REPLACE INTO [{table}] ({columns}) VALUES {rows};

If the record already exists, it will be entirely replaced by a new record - as opposed to updating any specified fields but leaving existing fields as they are (the behaviour of "upsert" in SQLite itself).

I started playing with this in #404 and got good results but it didn't work in Python 3.5. As of #627 I don't support 3.5 any more so this can go ahead.

Rendering templates in async mode will mean that template plugins can include async code... which opens the door to custom template functions that execute SQL queries!

Now that we support 3.8 (#627) datasette publish should always deploy using Python 3.8.

Closes #629

The unit tests currently pass under Python 3.8.

But... when you actually attempt to run Datasette you get an error: ~/Dropbox/Development/datasette $ venv-py3.8.0/bin/datasette --memory -p 8855 Serve! files=() (immutables=()) on port 8855 Traceback (most recent call last): File "venv-py3.8.0/bin/datasette", line 11, in <module> load_entry_point('datasette', 'console_scripts', 'datasette')() File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/click/core.py", line 764, in __call__ return self.main(*args, **kwargs) File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/click/core.py", line 717, in main rv = self.invoke(ctx) File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/click/core.py", line 1137, in invoke return _process_result(sub_ctx.command.invoke(sub_ctx)) File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/click/core.py", line 956, in invoke return ctx.invoke(self.callback, **ctx.params) File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/click/core.py", line 555, in invoke return callback(*args, **kwargs) File "/Users/simonw/Dropbox/Development/datasette/datasette/cli.py", line 365, in serve uvicorn.run(ds.app(), host=host, port=port, log_level="info") File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/uvicorn/main.py", line 279, in run server.run() File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/uvicorn/main.py", line 305, in run self.config.setup_event_loop() File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/uvicorn/config.py", line 218, in setup_event_loop loop_setup() File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/uvicorn/loops/auto.py", line 3, in auto_loop_setup import uvloop File "/Users/simonw/Dropbox/Development/datasette/venv-py3.8.0/lib/python3.8/site-packages/uvloop/__init__.py", line 7, in <module> from .loop import Loop as __BaseLoop # NOQA File "uvloop/includes/stdlib.pxi", line 114, in init uvloop.loop AttributeError: module 'sys' has no attribute 'set_coroutine_wrapper' ~/Dropbox/Development/datasette $ If Datasette doesn't work under Python 3.8 the tests should fail.