I use the same pattern as HTMx’s “Click to Edit” example[0], except that
my edit form is triggered by submit and by focus out of the tags input.
I could not, however, use the standard focus out event because it would
also trigger when removing a tag with the mouse, as for a moment the
remove button has the focus and the search input dispatches a bubbling
focusout. I had to resort to a custom event for that, but i am not
happy with it.
The autofocus attribute seems to do nothing in this case, so i need to
manually change the focus to the new input with JavaScript. However,
this means that i can not use the same input ID for all the forms
because getElementById would always return the first in document order,
changing the focus to that same element and automatically submit the
form due to focus out. That’s why in this form i append the invoice’s
slug to the input’s ID.
Finally, this is the first time i am using an HTMx-only solution and i
needed a way to return back just the HTML for the <td>, without <title>,
breadcrumbs, or <dialog>. In principle, the template would be the
“layout”, but then i would need to modify everything to check whether
the template file is empty, or something to that effect, so instead i
created a “standalone” template for these cases.
[0]: https://htmx.org/examples/click-to-edit/
For some reason, i was looking at the value of the focus’ **target**,
which is not my search field at all, but whatever control the focus
changes **to**. It that new control is an input with value, then it
created a new tag with whatever my search field had, which could be the
empty string.
I realized that the event handlers that i was setting when creating the
tags input and the multi-select controls were not removed just because
these elements are no longer in the document, and kept firing again and
again.
I no longer can use an anonymous function, because removeEventListener
would not match it with the one passed to addEventListener. I also have
to bind the handler to `this` in order to keep having access to the
object, and, again, can not do it in the call to addEventListener, or
i would get a different function each time.
I added the check to see if the element is connected inside the
connectedCallback because the documentation warns that this callback
“may be called once your element is no longer connected”[0], and i
understood it to mean that the connected and disconnected callbacks
could be called our of order, thus it would be possible to add event
listeners that would not be removed—again.
I am not actually sure where i have to do the same for the rest of the
“internal” events.
[0]: https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_custom_elements#using_the_lifecycle_callbacks
This is mainly because i sometimes think that the tag is accepted just
because it is there in the input, but actually it is not being used at
all. I fear more people would do the same mistake.
It all started when i wanted to try to filter invoices by multiple tags
using an “AND”, instead of “OR” as it was doing until now. But
something felt off and seemed to me that i was doing thing much more
complex than needed, all to be able to list the tags as a suggestion
in the input field—which i am not doing yet.
I found this article series[0] exploring different approaches for
tagging, which includes the one i was using, and comparing their
performance. I have not actually tested it, but it seems that i have
chosen the worst option, in both query time and storage.
I attempted to try using an array attribute to each table, which is more
or less the same they did in the articles but without using a separate
relation for tags, and i found out that all the queries were way easier
to write, and needed two joins less, so it was a no-brainer.
[0]: http://www.databasesoup.com/2015/01/tag-all-things.html
This makes reload only the <main> portion of the page, instead of the
whole thing, which to me looks faster; haven’t really measured it.
Like with duplicate, i had to add the location query argument when
inside the view page in order to return back to the same page, not the
index.
Had to add a new hidden field to the form to know whether, when the
request is HTMx-triggered, to refresh the page, as i do when duplicating
from the index, or redirect the client to the new invoice’s view page,
but only if i was duplicating from that same page, not the index.
Since i now have to target main when redirecting to the view page, so
i had to add a location structure with the required json fields and all
that, when “refreshing” i actually tell HTMx to open the index page
again, which seems faster, now that i am used to boosted links.
Changed the invoice number field’s type to search to add the delete icon
on Chromium. Firefox does not add that icon, but i do not care; it is
still better that type="text".
Had to emit the change event to the numerus-tag field, otherwise the
form would not detect the change.
I also can not use keyup as a trigger because the changed modifier can
not be used in the <form>, as nothing ever changes, i do not know how to
trigger the form from children (i.e., data-hx-trigger on the <input>
does nothing), and i can not trigger for just any keyup, or i would
make the request even if they only moved the cursor with the arrow keys,
which is very confusing as Firefox resets the position (this may be due
the fact that i reload the whole <main>, but still).
This is for the unusual case of products without taxes, that PostgreSQL
by default would generate an array with a single null value in it, but
then pgx would not be able to set that null to the string variable.
Initially, this field was meant to be left almost always blank, except
for when we deleted invoiced and had to “replace” its number with a new
invoice; using the automatic numbering in this cas would not “fill in”
the missing number in the sequence.
However, we decide to not allow removing invoicer not edit their
numbers, therefore, if everything goes as planned, there should not be
any gap in the sequence, and that field is rendered useless.
Oriol suggested making it a read-only field, both for new and edit
forms, but i do not think it makes sense to have a field if you can not
edit it at all, specially in the new invoice dialog, where it would
always be blank. In the edit form we already show the number in the
title and breadcrumbs, thus no need for the read-only field as
reference.
I still keep a Number member to the form struct, but is now a string
(kind of “a read-only field”, in a way) and just to be written in the
title or breadcrumbs. I did not like the idea of adding a new SQL
query just for that value.
In this case i have to use the same id for the dialog content in all
pages because, for now, there are a couple of forms that need to replace
it on submit—the new/edit form and the product selection form.
Unfortunately, HTMx does not have support for `formaction` attribute at
this point, so i had to use the workaround described in [0].
[0] https://github.com/bigskysoftware/htmx/issues/623
Instead of using links in the invoice tags, that we will replace with a
“click-to-edit field”, with Oriol agreed to add a form with filters that
includes not only the tags but also dates, customer, status, and the
invoice number.
This means i now need dynamic SQL, and i do not think this belongs to
the database (i.e., no PL/pgSQL function for that). I have looked at
query builder libraries for Golang, and did not find anything that
suited me: either they wanted to manage not only the SQL query but also
all structs, or they managed to confuse Goland’s SQL analyzer.
For now, at least, i am using a very simple approach with arrays, that
still confuses Goland’s analyzer, but just in a very specific part,
which i find tolerable—not that their analyzer is that great to begin
with, but that’s a story for another day.
We agreed with Oriol that this link would only serve to confuse people.
I initially added the link because i thought it was a shame to have to
navigate to the contact section to look or change the info of a customer
that you have an invoice for in front of you. However, it makes little
sense to be able to edit the contact from both sections, and we do not
have a “view page” for contacts to link to, thus the removal.
Had to add the editProductPage because now i need to know the slug in
order to build the form’s action link. I also added the `ProductName`
field because it was less awkward than using `.Form.Name` everywhere.
Mostly, the same problem as before: if the document title does not
reflect the application’s state, it becomes useless when there are
multiple open tabs.
In this case, however, i do not know how to tell HTMx to restore the
title to how it was before opening the dialog without a new request to
the server, that makes no sense when the dialog was closed without any
change whatsoever. Thus, i do it with JavaScript on the client side.
With Oriol we agreed that products should have tags, too, and that the
“tag pool”, as it were, should be shared with the one for invoices and
contacts.
Had to add the `company_id` attribute in the `using` clause for `tag` in
`MustFillFromDatabase`, even though it’s not strictly necessary, because
then PostgreSQL does not know which `company_id` attribute use for the
join with `company`—the one from `product` or the one from `tag`.
With Oriol we agreed that contacts should have tags, too, and that the
“tag pool”, as it were, should be shared with the one for invoices (and
all future tags we might add).
I added the contact_tag relation and tag_contact function, just like
with invoices, and then realized that the SQL queries that Go had to
execute were becoming “complex” enough: i had to get not only the slug,
but the contact id to call tag_contact, and all inside a transaction.
Therefore, i opted to create the add_contact and edit_contact functions,
that mirror those for invoice and products, so now each “major” section
has these functions. They also simplified a bit the handling of the
VATIN and phone numbers, because it is now encapsuled inside the
PL/pgSQL function and Go does not know how to assemble the parts.
We plan to tag also contacts and products using the same tag relation,
but different invoice_tag, contact_tag, and product_tag relations for
each one. However, the logic is the same for all three, hence it makes
more sense to put it into a PL/pgSQL with dynamic SQL. Moreover, the
SQL for tagging in add_invoice and edit_invoice where almost exactly
the same, the only difference was deleting the existing tags when
editing.
I do not execute the tag_relation function in its test suite because
by itself it does nothing without supporting invoice_tag, contact_tag,
or any such relation, so it is being tested in the suite for
tag_invoice.
We do not have any design yet for errors and other notifications, so i
followed material design, for now, since we already kind of use their
input fields design.
This time i decided to use AlpineJS because there is not that much HTML
code, and the transitioning is way easier to do in AlpineJS than it
would be with plain JavaScript—not to mention the bugs i would
introduce.
I am not sure if, at the end, all pages that now use
mustRenderAppTemplate will be replaced with mustRenderMainTemplate,
but for now i keep them separate to know which routes are already
“boosted”.
Had to change the data context for that template to include the Slug,
so that the <form> element can set the correct `action` instead of
using the current URI, as it is no longer “correct” (form-wise) when
using HTMx.
This is more or less the same as a multiselect, except that now it
adds a list of string element that you write into the search element.
It is supposed to fetch a list of tag suggestions from the server, but i
have not implemented it yet.
In that case, strings.Split() return an array with a single empty string
element, that does not pass the domain check for tag_name in the
database.
And an invoice with no tags would get an array of a single NULL in
array_agg, so i had to convert it to an empty string in order for it
to work as expected.
What i really set off on was to refactor the multiselect’s x-data
context to a separate JavaScript file.
I did not see the need at first, thinking that it would not matter
because it was used only in a template and i was not duplicating the
code in my files. However, i then realized that having the context
in the template means the visitor has to download it each and every time
it accesses a form with a multiselect, even if nothing changed, and,
worse, it would download it multiple times if there were many
multiselect controls.
It makes more sense to put all that into a file that the browser would
only download and parse once, if the proper caching is set.
Once i realized that, it was a shame that AlpineJS has no way to do
the same for the HTML structure[0], for the exact same reasons: not
wanting to download many times the same extra <template> and other
markup required to build the control for JavaScript users. And then i
remembered that this is supposed to be custom element’s main selling
point.
At first i tried to create a shadow DOW to replace the <select> with
the same <div> and <ul> that i used with Alpine, but it turns out that
<select> is not one of the allowed elements that can have a shadow root
attached[0].
Therefore, i changed the custom element to extend the <div> for the
<select> and <label> instead—the same element that had the x-init
context—, but i would have to define or include all the styles inside
the shadow DOM, and bring the lang attribute, for it to look like it
did before. Out with the shadow DOM, and modify the <div>’s contents
instead.
At this point the code was so far removed from the declarative way that
AlpineJS promotes that i did not see much value on using it, except for
its reactivity. But, given that this is such a small component, at the
end decided to write it all in plain JavaScript.
It is more code, at least looking only at the code i had to write, but
i love how i only have to add an is="numerus-multiselect" attribute to
HTML for it to work.
[0]: https://github.com/alpinejs/alpine/discussions/1205
[1]: https://developer.mozilla.org/en-US/docs/Web/API/Element/attachShadow
Had to replace the tags <ul> with a div with an input, so that the
browser can focus the keywoard there. For now i do not have a
focus-within CSS rule because we do no yet have a style for focus
highlight.
I have replaced the template for-loop to fill the options with the
JavaScript equivalent for two reasons. The first is that GoLand is very
stupid and can not handle that templating code inside the JavaScript
function and complains of non-existing problemes all the time.
The second is that, taking advantage of the input, i now have filtering
of options and have to remove accents from the label and convert it to
lowercase into a separate property just for that. I could do that with
a Go function, but it is something that i also have to do for the
input’s value when it changes, therefore i am forced to use JavaScript
and, if i am already using it for one string, it makes no sense to have
duplicate functionality in Go code.
The control still has missing aria attributes, and the list of options
is not yet navigable with the keyboard.
I had in the product edit page only because it was easier to test there
while i was developing it, but it is something that should be done for
all select[multiple], of course.
I removed the whole x-cloak thing because i am not sure what would
happen if i do something wrong and Alpine can not initialize the
multiselect; probably show nothing to the user. Now it shows the
native select a fraction of a second, but if i fuck it up at least the
user can still use the app.
I had to change the way /invoices/new and /invoices/batch are handled,
because httprouter was not happy with the new POST /invoices/:slug/edit
route, claiming that /invoices/:slug conflicts with the previously
existing routes.
I also could not make it work with the PATCH method, even though i
correctly added the patchMethod override function, therefore editing
invoices is also weird because i have to take into account the “quick”
invoice status change.
I use the same form for both new and edit invoices, because the only
changes are that we can not edit the invoice date and number, by
Oriol’s design, but must be able to change the status; very similar
forms.
Sometimes, depending on the order the tests are run, the edit_function
would try to insert a tag with a duplicate primary key, because the
sequence starts with 1 on an empty database. So, make sure the next
sequence value is after the primary keys i have manually set.
jordi fita mas