Summary of Inertia responses in different cases

[rkyoku]

Hi there!

I am not sure I totally understand how Inertia works (i.e. what it is expecting in this or that situation).

I can show you below what I understood about what is expected, but I would be really grateful if someone could correct me, show me where I am wrong, so that I have a perfect summary of what kind of Inertia responses I must provide in different situations.

1. Loading a page, or redirecting to another page

Standard response

http status: 200
headers: x-inertia = true
json: component, props, url

EDIT: I don't have much doubt about this one

2. Field error upon form submit

Ajax form submit, validation PHP side (well, server side). Provide "errors" prop.

http status: 303
headers: x-inertia = true
json: component, props (errors), url

Questions:

1. It seems the http status is irrelevant (errors still show in my form, even with a status 400)
2. Why are "component" and "url" required? I am staying on the same component... It makes my server-side code feel redundant and heavy (I am using plain PHP without a framework, therefore with a custom adapter I am writing) ; also it doesn't seem that Inertia's request is containing the current component like they do with partial reloads IIRC (which could have been handy to make the server-side code lighter)

3. Actual location redirect

When requiring a real redirect from the browser

http status: 409
headers: x-inertia = true, x-inertia-redirect = myurl
json: (empty)

No page data, as we redirect the user to new horizons!

4. Submit form success

When we don't redirect to another component (like we could do when adding a user and redirecting to their details)

I am not sure which response is required here... Maybe it depends on whether I want to display a specific (server-rendered) message upon success, or maybe I don't want to display anything...

Do I have to do a full-blown "page load" response? Or can I just respond "200 OK" or something?

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Summary: I would like to be able to write, without any fears of doing it wrong, the handling of different situations in my own Inertia adapter: onFormFieldError, onFormGenericError, onFormSuccess, onLoadPage, onActualRedirect

But I am not quire sure whether I am currently handling the requests properly...

Any help to see things more clearly would be super welcome! :)

Best,

[rkyoku]

EDIT: I battled to get something working... All I wanted was to respond to an Inertia request with an error to display in a form (in case a field did not match the proper format, for example), but without a "component" thing (i.e. without a full page visit with all that it implies). I spent all night and all day on it, getting (more or less...) help from Phind. My solution is complicated, because now I am manually sending an event to Inertia for loading the next Page if the POST request ended well, and I am manually calling setError if it did not, so that reactivity works. I feel that something easier is possible (I wrote a custom solution using Fetch and bypassing the $form standard post function), but even Phind can't seem to be able to find it. I'm not even sure my solution works properly (regarding the redirect to the new Page component, that I did not get enough time to test), but at least I got error management to work with reactivity! This solution allows me to reply to scenarios 2 and 4 from my original post, without having (if I understood things properly) to redirect to the current component and do another trip of http requests.