Product Listener

# Available variables:
#  - env: Odoo Environment on which the action is triggered
#  - model: Odoo Model of the record on which the action is triggered; is a void recordset
#  - record: record on which the action is triggered; may be void
#  - records: recordset of all records on which the action is triggered in multi-mode; may be void
#  - time, datetime, dateutil, timezone: useful Python libraries
#  - log: log(message, level='info'): logging function to record debug information in ir.logging table
#  - Warning: Warning Exception to use with raise
# To return an action, assign: action = {...}

# create a User called 'Listener' with the Warning Avatar and update ID on line 50

out_prefix = '<ul class="o_mail_thread_message_tracking">'
arrow = ' <span class="fa fa-long-arrow-right" role="img" aria-label="Changed" title="Changed"></span> '
out_suffix = '</ul>'
in_prefix = '<li><div class="o_thread_message_content">'
in_suffix = '</div></li>'

for record in records:
  message = out_prefix
  found = False
  for field_name in env.context['old_values'][record.id]:
    if not record.env['ir.model.fields'].search([('model_id','=','product.template'),('name','=',field_name),('tracking','>',0)]):
      field = record.env['ir.model.fields'].search([('model_id','=','product.template'),('name','=',field_name)])
      field_label = field.field_description + ': '
      field_type = field.ttype
      if field_type in ['boolean','char','date','datetime','float','html','integer','monetary','selection','text','many2one']:
        found = True
        old_value = env.context['old_values'][record.id][field_name] or ''
        new_value = record[field_name] or ''
        if field_type in ['boolean','char','date','datetime','html','integer','monetary','text']:
          old_value = str(old_value)
          new_value = str(new_value)
        elif field_type == 'selection':
          old_label = env['ir.model.fields.selection'].search([('field_id','=',field.id),('value','=',old_value)]).name or ''
          new_label = env['ir.model.fields.selection'].search([('field_id','=',field.id),('value','=',new_value)]).name or ''
          old_value = old_label
          new_value = new_label
        elif field_type == 'many2one':
          old_value = env.context['old_values'][record.id][field_name][1]
          new_value = record[field_name].display_name 
        else:
          old_value = '%.2f' % old_value
          new_value = '%.2f' % new_value
          
        message += in_prefix + field_label + old_value + arrow + new_value + in_suffix
      
  message += out_suffix
  if found:
    record.message_post(body = message,author_id = 14)