How can I add validator to Purchase Order(or other system doctypes)?

nnylyj · February 22, 2016, 11:03am

I want to add a validate function to Purchase Order, but I don’t want to override current validate method, how to append a custom validator to a doctype without modifying original codes?

If I create a hook to validate in a custom app, would it override origin or append?

kolate_sambhaji · February 22, 2016, 11:25am

@nnylyj
You can add custom script for this
Example:

frappe.ui.form.on("Purchase Order", "validate", function(frm) {
    if (frm.doc.from_date < get_today()) {
        msgprint("You can not select past date in From Date");
        validated = false;
    }
});

Here
http://frappe.github.io/erpnext/user/manual/en/customize-erpnext/custom-scripts/custom-script-examples/

nnylyj · February 22, 2016, 11:51am

thanks but I need to validate in backend, because I create po by API

kolate_sambhaji · February 22, 2016, 12:41pm

@nnylyj ok, then you can use hooks to call validate method

call your custom python function on validate event.
add this in hooks.py under doc_events

github.com

sbkolate/SF_Custom_Changes/blob/master/sf_custom_changes/hooks.py#L16


      
          app_color = "#589494"
          app_email = "info@systematrix.co.in"
          app_url = "https://github.com/Systematrix/SF_Custom_Changes"
          app_version = "12.6.0"
          fixtures = ["Custom Field",
          "Property Setter",
          "Custom Script",
          "Print Format",
          "Report"]
          
          
doc_events = {
          	"Purchase Invoice": {
          		"validate": "sf_custom_changes.sf_acc.purchase.validate_bill_no"
          	}
          }
          
          
# Includes in <head>
          # ------------------
          
          
# include js, css files in header of desk.html
          # app_include_css = "/assets/sf_custom_changes/css/sf_custom_changes.css"

write your python function, you have access to all field value using self.field_name.
To invalidate you can write frappe.throw(“message”)

github.com

sbkolate/SF_Custom_Changes/blob/master/sf_custom_changes/sf_acc/purchase.py#L28


      
          @frappe.whitelist(allow_guest=True)
          
          
def validate_mandatory(self):
          		# validate transaction date v/s delivery date
          		if self.delivery_date:
          			if getdate(self.bill_date) > getdate(self.posting_date):
          				frappe.throw(_("Expected Delivery Date cannot be before Sales Order Date"))
          
          
@frappe.whitelist(allow_guest=True)
          
          
def validate_bill_no(self, method):
          		if self.bill_no:
          			# validate bill no is unique
          			bill_list = frappe.db.sql("""select name from `tabPurchase Invoice` where bill_no=%s and docstatus=1 and is_recurring='0'""", self.bill_no)
          			if len(bill_list) > 0:
          				items = [e[0] for e in bill_list if e[0]!=self.name]
          				frappe.throw(_("Supplier Invoice Number must be unique. Current Supplier Invoice Number already exists for {0}").format(comma_and(items)))
          		if self.bill_date:
          				if getdate(self.bill_date) > getdate(self.posting_date):
          					frappe.throw(_("Supplier Invoice Date cannot be after Purchase Invoice Date"))

nnylyj · February 23, 2016, 1:03am

thanks, and a new problem is will the hook override previous validator or just append to previous validators?

Sangram · February 23, 2016, 5:30am

@nnylyj

It’s append to previous one.
Both functionality will run.

nnylyj · February 23, 2016, 6:12am

Thanks for the answer!

UPDATE:
I added a validate hook to a doctype, but nothing happened after clicking Save button.
WHEN the validate hook will be invoked?