Needed by https://github.com/simonw/datasette-backup/issues/6

https://docs.datasette.io/en/latest/binary_data.html

On my Mac, I run:

datasette . -p 8009 --config base_url:/datasette-prefix/

Then I edited /usr/local/etc/httpd/httpd.conf and add this section: LoadModule proxy_module lib/httpd/modules/mod_proxy.so LoadModule proxy_http_module lib/httpd/modules/mod_proxy_http.so ProxyPass /datasette-prefix/ http://localhost:8009/datasette-prefix/ I ran Apache in the foreground like so:

apachectl -X

Now hitting http://localhost:8081/datasette-prefix/fixtures/compound_three_primary_keys worked!

This should all be working correctly now.

OK, this should be working now. You can use the datasette.urls.static_plugins() method to generate the correct URLs in the extra_css_urls plugin hook: https://docs.datasette.io/en/latest/internals.html#datasette-urls

Implemented in a4ca26a2659d21779adf625183061d8879954c15

Here's the datasette-edit-templates plugin WIP I had before removing the hook: https://github.com/simonw/datasette-edit-templates/tree/82855c2612b84bc09c48fca885f831633a0d1552

I bet this is because I'm mucking around with one of those __ methods. I'll try just doing the non-underscore methods instead.

Here's the output of dir(str):

['__add__', '__class__', '__contains__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getnewargs__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mod__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__rmod__', '__rmul__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'capitalize', 'casefold', 'center', 'count', 'encode', 'endswith', 'expandtabs', 'find', 'format', 'format_map', 'index', 'isalnum', 'isalpha', 'isascii', 'isdecimal', 'isdigit', 'isidentifier', 'islower', 'isnumeric', 'isprintable', 'isspace', 'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'maketrans', 'partition', 'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip', 'split', 'splitlines', 'startswith', 'strip', 'swapcase', 'title', 'translate', 'upper', 'zfill']

It looks like this is specific to the way PrefixedUrlString is built. (Pdb) class Weird(str): pass (Pdb) isinstance(Weird('bob'), collections.abc.Awaitable) False So subclassing strings doesn't trigger this bug, but something about PrefixedUrlString causes the problem.

Here's the current PrefixedUrlString implementation:

https://github.com/simonw/datasette/blob/bf18b9ba175a7b25fb8b765847397dd6efb8bb7b/datasette/utils/init.py#L1015-L1035

Here's the core problem: (Pdb) isinstance('bob', collections.abc.Awaitable) False (Pdb) isinstance(PrefixedUrlString('bob'), collections.abc.Awaitable) *** TypeError: issubclass() arg 1 must be a class For some reason isinstance() does not like being handed an instance of PrefixedUrlString.

I wonder how Jinja's Markup() class works? It uses https://pypi.org/project/MarkupSafe/

It's a subclass of str, defined here: https://github.com/pallets/markupsafe/blob/master/src/markupsafe/init.py

Sample traceback: ``` <link rel="stylesheet" href="{{ urls.static('app.css') }}?{{ app_css_hash }}"> /opt/hostedtoolcache/Python/3.7.9/x64/lib/python3.7/site-packages/jinja2/asyncsupport.py:173: in auto_await if inspect.isawaitable(value): /opt/hostedtoolcache/Python/3.7.9/x64/lib/python3.7/inspect.py:226: in isawaitable isinstance(object, collections.abc.Awaitable)) /opt/hostedtoolcache/Python/3.7.9/x64/lib/python3.7/abc.py:139: in instancecheck return _abc_instancecheck(cls, instance)

cls = <class 'collections.abc.Awaitable'> subclass = <bound method PrefixedUrlString.__getattribute__.\<locals>.method of '/-/static/app.css'>

def __subclasscheck__(cls, subclass):
    """Override for issubclass(subclass, cls)."""

  return _abc_subclasscheck(cls, subclass)

E TypeError: issubclass() arg 1 must be a class `` This is within Jinja. It looks like Jinja really doesn't like methods that return non-string objects likePrefixedUrlString`.

These plugins were not designed to be actually hosted online, so they do some nasty things like linking to the made-up plugin-example.com domain. I should fix that.

Demo:

• https://latest.datasette.io/fixtures/facetable?_bot=1
• https://latest.datasette.io/fixtures/simple_view?_bot=1

This is working. Go to https://latest.datasette.io/login-as-root and click the button, then visit this page to see extra content added by plugins: https://latest.datasette.io/fixtures/compound_three_primary_keys

Needs a way to login as root, seeing as several plugins only show extra content if the user is logged in as root.

It bothers me that these aren't visible in any public demos. Maybe latest.datasette.io should include the my_plugins.py and my_plugins2.py plugins?

1041 can also benefit from the string subclass that shows that base_url has been added.

For the 0.51 release I'm going to add tests that show this works on view pages. I won't implement it for query pages.

Should the hook provide an indication that it's running on a different type of page? I think yes for queries. Not sure about views - they behave very much like tables, and the plugin can always introspect to see if something is a view if it needs to.

I've removed this plugin hook in #1073.

Here's the proof of concept FunctionLoader that showed me that this wasn't going to work: ```diff diff --git a/datasette/app.py b/datasette/app.py index 4b28e71..b076be7 100644 --- a/datasette/app.py +++ b/datasette/app.py @@ -21,7 +21,7 @@ from pathlib import Path from markupsafe import Markup from itsdangerous import URLSafeSerializer import jinja2 -from jinja2 import ChoiceLoader, Environment, FileSystemLoader, PrefixLoader +from jinja2 import ChoiceLoader, Environment, FileSystemLoader, FunctionLoader, PrefixLoader from jinja2.environment import Template from jinja2.exceptions import TemplateNotFound import uvicorn @@ -300,6 +300,7 @@ class Datasette: template_paths.append(default_templates) template_loader = ChoiceLoader( [ + FunctionLoader(self._load_template_from_plugins), FileSystemLoader(template_paths), # Support {% extends "default:table.html" %}: PrefixLoader( @@ -322,6 +323,17 @@ class Datasette: self._root_token = secrets.token_hex(32) self.client = DatasetteClient(self)

• def _load_template_from_plugins(self, template):

• "If auto reloading is enabled it’s called to check if the template changed"

• uptodatefunc = lambda: True
• source = pm.hook.load_template(
• template=template,
• datasette=self,
• )
• if source is None:
• return None
• return source, template, uptodatefunc + @property def urls(self): return Urls(self) @@ -719,35 +731,7 @@ class Datasette: else: if isinstance(templates, str): templates = [templates] -

• Give plugins first chance at loading the template

• break_outer = False
• plugin_template_source = None
• plugin_template_name = None
• template_name = None
• for template_name in templates:
• if break_outer:
• break
• plugin_template_source = pm.hook.load_template(
• template=template_name,
• request=request,
• datasette=self,
• )
• plugin_template_source = await await_me_maybe(plugin_template_source)
• if plugin_template_source:
• break_outer = True
• plugin_template_name = template_name
• break
• if plugin_template_source is not None:
• template = self.jinja_env.from_string(plugin_template_source)
• else:
• template = self.jinja_env.select_template(templates)
• for template_name in templates:
• from_plugin = template_name == plugin_template_name
• used = from_plugin or template_name == template.name
• templates_considered.append(
• {"name": template_name, "used": used, "from_plugin": from_plugin}
• )
• template = self.jinja_env.select_template(templates) body_scripts = [] # pylint: disable=no-member for extra_script in pm.hook.extra_body_script( diff --git a/datasette/hookspecs.py b/datasette/hookspecs.py index ca84b35..7804def 100644 --- a/datasette/hookspecs.py +++ b/datasette/hookspecs.py @@ -50,7 +50,7 @@ def extra_template_vars(

@hookspec(firstresult=True) -def load_template(template, request, datasette): +def load_template(template, datasette): "Load the specified template, returning the template code as a string"

diff --git a/docs/plugin_hooks.rst b/docs/plugin_hooks.rst index 3c57b6a..8f2704e 100644 --- a/docs/plugin_hooks.rst +++ b/docs/plugin_hooks.rst @@ -273,15 +273,12 @@ Example: `datasette-cluster-map <https://github.com/simonw/datasette-cluster-map

.. _plugin_hook_load_template:

-load_template(template, request, datasette)

+load_template(template, datasette) +----------------------------------

template - string The template that is being rendered, e.g. database.html

-request - object or None - The current HTTP :ref:internals_request. This can be None if the request object is not available. - datasette - :ref:internals_datasette You can use this to access plugin configuration options via datasette.plugin_config(your_plugin_name) ```