Thanks @russss!
* Add register_output_renderer hook
This changeset refactors out the JSON renderer and then adds a hook and
dispatcher system to allow custom output renderers to be registered.
The CSV output renderer is untouched because supporting streaming
renderers through this system would be significantly more complex, and
probably not worthwhile.
We can't simply allow hooks to be called at request time because we need
a list of supported file extensions when the request is being routed in
order to resolve ambiguous database/table names. So, renderers need to
be registered at startup.
I've tried to make this API independent of Sanic's request/response
objects so that this can remain stable during the switch to ASGI. I'm
using dictionaries to keep it simple and to make adding additional
options in the future easy.
Fixes#440
Prior to this commit Datasette would calculate the content hash of every
database and redirect to a URL containing that hash, like so:
https://v0-27.datasette.io/fixtures => https://v0-27.datasette.io/fixtures-dd88475
This assumed that all databases were opened in immutable mode and were not
expected to change.
This will be changing as a result of #419 - so this commit takes the first step
in implementing that change by changing this default behaviour. Datasette will
now only redirect hash-free URLs under two circumstances:
* The new `hash_urls` config option is set to true (it defaults to false).
* The user passes `?_hash=1` in the URL
* table.csv?_stream=1 to download all rows - refs #266
This option causes Datasette to serve ALL rows in the table, by internally
following the _next= pagination links and serving everything out as a stream.
Also added new config option, allow_csv_stream, which can be used to disable
this feature.
* New config option max_csv_mb limiting size of CSV export
These new querystring arguments can be used to request expanded foreign keys
in both JSON and CSV formats.
?_labels=on turns on expansions for ALL foreign key columns
?_label=COLUMN1&_label=COLUMN2 can be used to pick specific columns to expand
e.g. `Street_Tree_List.json?_label=qSpecies&_label=qLegalStatus`
{
"rowid": 233,
"TreeID": 121240,
"qLegalStatus": {
"value" 2,
"label": "Private"
}
"qSpecies": {
"value": 16,
"label": "Sycamore"
}
"qAddress": "91 Commonwealth Ave",
...
}
The labels option also works for the HTML and CSV views.
HTML defaults to `?_labels=on`, so if you pass `?_labels=off` you can disable
foreign key expansion entirely - or you can use `?_label=COLUMN` to request
just specific columns.
If you expand labels on CSV you get additional columns in the output:
`/Street_Tree_List.csv?_label=qLegalStatus`
rowid,TreeID,qLegalStatus,qLegalStatus_label...
1,141565,1,Permitted Site...
2,232565,2,Undocumented...
I also refactored the existing foreign key expansion code.
Closes#233. Refs #266.
Simon Willison