- Feb 2023
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guides.rubyonrails.org guides.rubyonrails.org
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If you already have an instance of your model, you can start a transaction and acquire the lock in one go using the following code: book = Book.first book.with_lock do # This block is called within a transaction, # book is already locked. book.increment!(:views) end
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- Aug 2021
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stackoverflow.com stackoverflow.com
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the tuple() function you need can be succinctly written as: export type Lit = string | number | boolean | undefined | null | void | {}; export const tuple = <T extends Lit[]>(...args: T) => args;
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- Apr 2021
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stackoverflow.com stackoverflow.com
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I came up with the following little helper function
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- Feb 2021
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trailblazer.to trailblazer.to
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To understand this helper, you should understand that every step invocation calls Output() for you behind the scenes. The following DSL use is identical to the one [above]. class Execute < Trailblazer::Activity::Railway step :find_provider, Output(Trailblazer::Activity::Left, :failure) => Track(:failure), Output(Trailblazer::Activity::Right, :success) => Track(:success)
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For branching out a separate path in an activity, use the Path() macro. It’s a convenient, simple way to declare alternative routes
Seems like this would be a very common need: once you switch to a custom failure track, you want it to stay on that track until the end!!!
The problem is that in a Railway, everything automatically has 2 outputs. But we really only need one (which is exactly what Path gives us). And you end up fighting the defaults when there are the automatic 2 outputs, because you have to remember to explicitly/verbosely redirect all of those outputs or they may end up going somewhere you don't want them to go.
The default behavior of everything going to the next defined step is not helpful for doing that, and in fact is quite frustrating because you don't want unrelated steps to accidentally end up on one of the tasks in your custom failure track.
And you can't use
fail
for custom-track steps becase that breaksmagnetic_to
for some reason.I was finding myself very in need of something like this, and was about to write my own DSL, but then I discovered this. I still think it needs a better DSL than this, but at least they provided a way to do this. Much needed.
For this example, I might write something like this:
step :decide_type, Output(Activity::Left, :credit_card) => Track(:with_credit_card) # Create the track, which would automatically create an implicit End with the same id. Track(:with_credit_card) do step :authorize step :charge end
I guess that's not much different than theirs. Main improvement is it avoids ugly need to specify end_id/end_task.
But that wouldn't actually be enough either in this example, because you would actually want to have a failure track there and a path doesn't have one ... so it sounds like Subprocess and a new self-contained ProcessCreditCard Railway would be the best solution for this particular example... Subprocess is the ultimate in flexibility and gives us all the flexibility we need)
But what if you had a path that you needed to direct to from 2 different tasks' outputs?
Example: I came up with this, but it takes a lot of effort to keep my custom path/track hidden/"isolated" and prevent other tasks from automatically/implicitly going into those steps:
class Example::ValidationErrorTrack < Trailblazer::Activity::Railway step :validate_model, Output(:failure) => Track(:validation_error) step :save, Output(:failure) => Track(:validation_error) # Can't use fail here or the magnetic_to won't work and Track(:validation_error) won't work step :log_validation_error, magnetic_to: :validation_error, Output(:success) => End(:validation_error), Output(:failure) => End(:validation_error) end
puts Trailblazer::Developer.render o Reloading... #<Start/:default> {Trailblazer::Activity::Right} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=validate_model> #<Trailblazer::Activity::TaskBuilder::Task user_proc=validate_model> {Trailblazer::Activity::Left} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Right} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=save> #<Trailblazer::Activity::TaskBuilder::Task user_proc=save> {Trailblazer::Activity::Left} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Right} => #<End/:success> #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Left} => #<End/:validation_error> {Trailblazer::Activity::Right} => #<End/:validation_error> #<End/:success> #<End/:validation_error> #<End/:failure>
Now attempt to do it with Path... Does the Path() have an ID we can reference? Or maybe we just keep a reference to the object and use it directly in 2 different places?
class Example::ValidationErrorTrack::VPathHelper1 < Trailblazer::Activity::Railway validation_error_path = Path(end_id: "End.validation_error", end_task: End(:validation_error)) do step :log_validation_error end step :validate_model, Output(:failure) => validation_error_path step :save, Output(:failure) => validation_error_path end
o=Example::ValidationErrorTrack::VPathHelper1; puts Trailblazer::Developer.render o Reloading... #<Start/:default> {Trailblazer::Activity::Right} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=validate_model> #<Trailblazer::Activity::TaskBuilder::Task user_proc=validate_model> {Trailblazer::Activity::Left} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Right} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=save> #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Right} => #<End/:validation_error> #<Trailblazer::Activity::TaskBuilder::Task user_proc=save> {Trailblazer::Activity::Left} => #<Trailblazer::Activity::TaskBuilder::Task user_proc=log_validation_error> {Trailblazer::Activity::Right} => #<End/:success> #<End/:success> #<End/:validation_error> #<End/:failure>
It's just too bad that:
- there's not a Railway helper in case you want multiple outputs, though we could probably create one pretty easily using Path as our template
- we can't "inline" a separate Railway acitivity (Subprocess "nests" it rather than "inlines")
Tags
- tip
- verbose / noisy / too much boilerplate
- concise
- demystified
- useful
- being explicit
- equivalent code
- example: not how you would actually do it (does something wrong/bad/nonideal illustrating but we should overlook it because that's not the one thing the example is trying to illustrate/show us)
- automatic
- flexibility
- powerful
- helper functions
Annotators
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github.com github.com
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# Set the model name to change the field names generated by the Rails form helpers def self.model_name=(name) @_model_name = ActiveModel::Name.new(self, nil, name) end
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github.com github.com
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The assert method is used by all the other assertions. It pushes the second parameter to the list of errors if the first parameter evaluates to false or nil.
Seems like these helper functions could be just as easily used in ActiveRecord models. Therefore, they should be in a separate gem, or at least module, that can be used in both these objects and ActiveRecord objects.
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- Jan 2021
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atomiks.github.io atomiks.github.ioFAQ1
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Can I use the title attribute?Yes. The content prop can be a function that receives the reference element as an argument and returns a string or element.tippy('button', { content(reference) { const title = reference.getAttribute('title'); reference.removeAttribute('title'); return title; }, });The title attribute should be removed once you have its content so the browser's default tooltip isn't displayed along with the tippy.
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atomiks.github.io atomiks.github.io
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We can make content a function that receives the reference element (button in this case) and returns template content:
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github.com github.com
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// super-simple CSS Object to string serializer const css = obj => Object.entries(obj || {}) .map(x => x.join(":")) .join(";");
Tags
Annotators
URL
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github.com github.com
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const deinitPopper = () => { if (popperInstance) { popperInstance.destroy(); popperInstance = null; } };
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URL
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thewebdev.info thewebdev.info
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PopupState HelperTo make managing the popover state easier, we can use the material-ui-popup-state library to manage the state.
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- Oct 2020
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svelte.dev svelte.dev
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whenValueChanges whenValueBecomes
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