Laravel MultiStep Forms

https://packagist.org/packages/bayareawebpro/laravel-multistep-forms

Multistep Form Builder is a "responsable" class that can be returned from controllers.

• Specify a view to use Blade or go headless with JSON for use with Javascript frameworks.
• Configure the rules, messages and supporting data for each step with simple arrays.
• Submit to the same route multiple times to merge each validated request into a namespaced session key.
• Hook into each step before or after validation to interact with the form or return a response.

Installation

composer require bayareawebpro/laravel-multistep-forms

Example Usage

<?php

use BayAreaWebPro\MultiStepForms\MultiStepForm;

// Render a view with data.
return Form::make('my-form', [
        'title' => 'MultiStep Form'
    ])

    // Namespace the session data.
    ->namespaced('my-session-key')

    // Allow backwards navigation via get request. ?form_step=x
    ->canNavigateBack(true)

    // Tap invokable Class __invoke(Form $form)
    ->tap(new InvokableClass)

    // Before x step validation...
    ->beforeStep(1, function (MultiStepForm $form) {
        // Maybe return early or redirect?
    })
    // Before all step validation...
    ->beforeStep('*', function (MultiStepForm $form) {
        // Maybe return early or redirect?
    })

    // Validate Step 1
    ->addStep(1, [
        'rules' => ['name' => 'required'],
        'messages' => ['name.required' => 'Your name is required.'],
    ])

    // Validate Step 2
    ->addStep(2, [
        'rules' => ['role'  => 'required|string'],
        'data'  => ['roles' => fn()=>Role::forSelection()] // Lazy Loaded Closure
    ])

    // Add non-validated step...
    ->addStep(3,[
       'data' => ['message' => "Great Job, Your Done!"]
    ])

    // After step validation...
    ->onStep(3, function (MultiStepForm $form) {
        // Specific step, logic if needed.
    })
    ->onStep('*', function (MultiStepForm $form) {
        // All steps, logic if needed.
    })
   
    // Modify data before saved to session after each step.
    ->beforeSave(function(array $data) {
    
        // Transform non-serializable objects to paths, array data etc...
        return $data;
    })
   
    // Modify data before saved to session after each step.
    ->onComplete(function(MultiStepForm $form) {
    
        // Final submission logic.
    })
;

---

Make New Instance

Make a new instance of the builder class with optional view and data array. You should always set the namespace for the form session to avoid conflicts with other parts of your application that use the session store.

• GET requests will load the form state and data for the saved current step or fallback to step 1.
• POST,PUT,PATCH etc... will validate and process the request for any step and proceed to the next step.
• DELETE will reset the session state and redirect back (blade), or return a JsonResponse.
• Backwards navigation (via get param) can be enabled via the canNavigateBack method.

<?php

use BayAreaWebPro\MultiStepForms\MultiStepForm;

$form = MultiStepForm::make('onboarding.start', [
    'title' => 'Setup your account'
]);

$form->namespaced('onboarding');
$form->canNavigateBack(true);

---

Configure Steps

Define the rules, messages and data for the step. Data will be merged with any view data defined in the make method and be included in the JsonResponse.

** Use a Closure to lazy load data per-key.

Use an array:

$form->addStep(2, [
    'rules' => [
        'role' => 'required|string'
    ],
    'messages' => [
        'role.required' => 'Your name is required.'
    ],
    'data' => [
        'roles' => fn() => Role::query()...,
    ],
])

Or use an invokable class (recommended)

use BayAreaWebPro\MultiStepForms\MultiStepForm;

class ProfileStep
{
    public function __construct(private int $step)
    {
        //
    }
    
    public function __invoke(MultiStepForm $form) 
    {
        $form->addStep($this->step, [
            'rules' => [
                'name' => 'required|string'
            ],
            'messages' => [
                'name.required' => 'Your name is required.'
            ],
            'data' => [
                'placeholders' => [
                    'name' => 'Enter your name.'
                ]
            ],
        ]);
    }
}

$form->tap(new ProfileStep(1));

---

BeforeStep / OnStep Hooks

Define a callback to fired before a step has been validated. Step Number or * for all.

• Use a step integer, or asterisk (*) for all steps.
• You can return a response from these hooks.

$form->beforeStep('*', function(MultiStepForm $form){
    //
});
$form->onStep('*', function(MultiStepForm $form){
    //
});
$form->onComplete(function(MultiStepForm $form){
    //
});

Handle UploadedFiles

Specify a callback used to transform UploadedFiles into paths.

use Illuminate\Http\UploadedFile;

$form->beforeSave(function(array $data){
    if($data['avatar'] instanceof UploadedFile){
        $data['avatar'] = $data['avatar']->store('avatars');
    }
    return $data;
});

Reset / Clear Form

• Ajax: Submit a DELETE request to the form route.
• Blade: Use an additional submit button that passes a boolean (truthy) value.

<button type="submit" name="reset" value="1">Reset</button>

JSON Response Schema

The response returned will have two properties:

{
  "form": {
    "form_step": 1
  },
  "data": {}
}

Public Helper Methods

stepConfig

Get the current step configuration (default), or pass an integer for a specific step:

$form->stepConfig(2): Collection

getValue

Get a field value (session / old input) or fallback:

$form->getValue('name', 'John Doe'): mixed

setValue

Set a field value and store in the session:

$form->setValue('name', 'Jane Doe'): MultiStepForm

save

Merge and save key/values array directly to the session (does not fire beforeSaveCallback):

$form->save(['name' => 'Jane Doe']): MultiStepForm

reset

Reset the form state to defaults passing an optional array of data to seed.

$form->reset(['name' => 'Jane Doe']): MultiStepForm

withData

Add additional non-form data to all views and responses:

$form->withData(['date' => now()->toDateString()]);

currentStep

Get the current saved step number:

$form->currentStep(): int

requestedStep

Get the incoming client-requested step number:

$form->requestedStep(): int

isStep

Is the current step the provided step:

$form->isStep(3): bool

prevStepUrl

Get the previous step url.

$form->prevStepUrl(): string|null

lastStep

Get the last step number:

$form->lastStep(): int

isLastStep

Is the current step the last step:

$form->isLastStep(): bool

isPast,isActive,isFuture

// Boolean Usage
$form->isPast(2): bool
$form->isActive(2): bool
$form->isFuture(2): bool

// Usage as HTML Class Helpers
$form->isPast(2, 'truthy-class', 'falsy-class'): string
$form->isActive(2, 'truthy-class', 'falsy-class'): string
$form->isFuture(2, 'truthy-class', 'falsy-class'): string

---

Blade Example

Data will be injected into the view as well as the form itself allowing you to access the form values and other helper methods.

<?php
use BayAreaWebPro\MultiStepForms\MultiStepForm as Form;

$form = Form::make('my-view', $data);
$form->namespaced('onboarding');
$form->canNavigateBack(true);

<form method="post" action="{{ route('submit') }}">
    <input type="hidden" name="form_step" value="{{ $form->currentStep() }}">
    @csrf
    <a
        href="{{ route('submit', ['form_step' => 1]) }}"
        class="{{ $form->isPast(1, 'text-blue-500', $form->isActive(1, 'font-bold', 'disabled')) }}">
        Step 1
    </a>
    <a
        href="{{ route('submit', ['form_step' => 2]) }}"
        class="{{ $form->isPast(2, 'text-blue-500', $form->isActive(2, 'font-bold', 'disabled')) }}">
        Step 2
    </a>
    <a
        href="{{ route('submit', ['form_step' => 3]) }}"
        class="{{ $form->isPast(3, 'text-blue-500', $form->isActive(3, 'font-bold', 'disabled')) }}">
        Step 3
    </a>

    
    @switch($form->currentStep())
    
        @case(1)
            <label>Name</label>
            <input type="text" name="name" value="{{ $form->getValue('name') }}">
            @error('name') 
                <p>{{ $errors->first('name') }}</p>
            @enderror
        @break
    
        @case(2)
            <label>Role</label>
            <input type="text" name="role" value="{{ $form->getValue('role') }}">
             @error('role') 
                <p>{{ $errors->first('role') }}</p>
            @enderror
        @break
    
        @case(3)
            <p>Review your submission:</p>
            <p>
             Name: {{ $form->getValue('name') }}<br>
             Role: {{ $form->getValue('role') }}<br>
            </p>
        @break
    
    @endswitch
    
    @if($form->isLastStep())
        <button type="submit" name="submit">Save</button>
        <button type="submit" name="reset" value="1">Reset</button>
    @else
        <button type="submit" name="submit">Continue</button>
    @endif

</form>

Vue Example

Form state and data will be returned as JSON when no view is specified or the request prefers JSON. You can combine both techniques to use Vue within blade as well.

<v-form route="{{ route('onboarding') }}">
    <template v-slot:default="{form, options, errors, reset, back}">

        <nav aria-label="Steps" v-if="form.form_step < 4">
            <a
                @click="back(1)"
                :class="{'text-gray-500': form.form_step > 1, 'text-blue-500': form.form_step === 1}">
                Step 1
            </a>
            <a
                @click="back(2)"
                :class="{'text-gray-500': form.form_step > 2, 'text-blue-500': form.form_step === 2}">
                Step 2
            </a>
            <a
                @click="back(3)"
                :class="{'text-gray-500': form.form_step > 3, 'text-blue-500': form.form_step === 3}">
                Step 3
            </a>
        </nav>

        <template v-if="form.form_step === 1">
            <v-input
                name="name"
                label="Name"
                :errors="errors"
                v-model="form.name">
            </v-input>
        </template>

        <template v-if="form.form_step === 2">
            <v-input
                name="email"
                label="Email"
                :errors="errors"
                v-model="form.email">
            </v-input>
        </template>

        <template v-if="form.form_step === 3">
            <v-input
                name="phone"
                label="Phone"
                :errors="errors"
                v-model="form.phone">
            </v-input>
        </template>

        <template v-if="form.form_step === 4">
            <ul>
                <li>Name: @{{ form.name }}</li>
                <li>Email: @{{ form.email }}</li>
                <li>Phone: @{{ form.phone }}</li>
            </ul>
        </template>

        <template v-if="form.form_step <= 4">
            <button type="submit">Save</button>
            <button type="button" @click="reset">Reset</button>
        </template>
        <template v-else>
            <button type="submit">Done</button>
        </template>
    </template>
</v-form>

Example Form Component

<script>
  export default {
    name: 'v-form',
    props: ['route'],
    data: () => ({
      errors: {},
      options: {},
      form: {form_step: 1},
    }),
    methods: {
      reset() {
        this.form.reset = 1
        this.submit()
      },
      back(step) {
        if (step < this.form.form_step) {
          this.fetch({form_step: step})
        }
      },
      fetch(params = {}) {
        axios
            .get(this.route, {params})
            .then(this.onResponse)
            .catch(this.onError)
      },
      submit() {
        axios
            .post(this.route, this.form)
            .then(this.onResponse)
            .catch(this.onError)
      },
      onError({response}) {
        this.errors = response.data.errors
      },
      onResponse({data}) {
        this.errors = {}
        this.options = (data.data || {})
        this.form = (data.form || {})
      },
    },
    created() {
      this.fetch()
    }
  }
</script>
<template>
  <form @submit.prevent="submit">
    <slot
        :form="form"
        :errors="errors"
        :options="options"
        :back="back"
        :reset="reset"
    />
  </form>
</template>

Example Input Component

<script>
  export default {
    name: "v-form-input",
    emits: ['update:modelValue'],
    props: ['name', 'modelValue', 'errors'],
    computed: {
      field: {
        get() {
          return this.modelValue
        },
        set(val) {
          return this.$emit('update:modelValue', val)
        }
      }
    }
  }
</script>
<template>
  <input
      type="text"
      :name="name"
      v-model="field"
      class="form-input"
  />
  <div v-if="errors[name]">
    {{ errors[name][0] }}
  </div>
</template>