Laravel Workflows using models

nextstage.php

<?php

// This isn't quite the same as the production code, but I wanted to be clear in this demo!

class LoanApplication extends Model 
{
    public function getNextStage() ?WorkflowStage 
    {
        $nextSequence = $this->workflow->sequences()
                              ->where('sequence_number', $this->current_sequence_number + 1)
                              ->first();
        
        if(is_null($nextSequence) {
            return null;
        } else {
            return $nextSequence->stage;
        }
    }
    
   public function workflow()
   {
      return $this->belongsTo(Workflow::class);  
   }
}
           
class Workflow extends Model
{
    public function sequences()
    {
        return $this->hasMany(WorkflowSequences::class);
    }
}
           
class WorkflowSequence extends Model 
{    
    public function stage()
    {
        return $this->belongsTo(WorkflowStage::class, 'workflow_stage_id);
    }
}

summary.md

Models

Workflow:

• id
• name

WorkflowStage:

• id
• name

WorkflowSequence:

• id
• workflow_id
• workflow_stage_id
• sequence_number

YourItem (say, Loan Application):

• your other stuff
• workflow_id
• current_sequence_number
• could also cache the current stage here, but not necessary

tables.md

Example of stages

id	name
1	Applied
47	In Review
98	Awaiting References

(the order of this doesnt matter)

Example of sequences, assume we have a workflow with id 1 "basic application process"

id	workflow_id	workflow_stage_id	sequence_number
1	1	1	1
2	1	98	2
3	1	47	3

Then we have a LoanApplication which is "Awaiting References" with:

• workflow_id: 1
• current_sequence_number: 2