From dabaa9aea5d42a749b2c5e8a28f4a2af0e8c5a9f Mon Sep 17 00:00:00 2001
From: Oliver <oliver.henry.walters@gmail.com>
Date: Mon, 1 Nov 2021 23:40:21 +1100
Subject: [PATCH] Adds a function to construct an "absolute" URL

Useful for providing an external link (e.g. in an email)
---
 InvenTree/InvenTree/helpers.py          | 27 +++++++++++++++++++++++++
 InvenTree/report/templatetags/report.py | 14 ++++---------
 2 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/InvenTree/InvenTree/helpers.py b/InvenTree/InvenTree/helpers.py
index 319b88cb09..4b0f31a702 100644
--- a/InvenTree/InvenTree/helpers.py
+++ b/InvenTree/InvenTree/helpers.py
@@ -69,6 +69,33 @@ def getStaticUrl(filename):
     return os.path.join(STATIC_URL, str(filename))
 
 
+def construct_absolute_url(url):
+    """
+    Construct (or attempt to construct) an absolute URL from a relative URL.
+
+    This is useful when (for example) sending an email to a user with a link
+    to something in the InvenTree web framework.
+
+    This requires the BASE_URL configuration option to be set!
+    """
+
+    base = str(InvenTreeSetting.get_setting('INVENTREE_BASE_URL'))
+
+    url = str(url)
+
+    if not base:
+        return url
+
+    # Strip trailing slash from base url
+    if base.endswith('/'):
+        base = base[:-1]
+
+    if url.startswith('/'):
+        url = url[1:]
+
+    url = f"{base}/{url}"
+
+
 def getBlankImage():
     """
     Return the qualified path for the 'blank image' placeholder.
diff --git a/InvenTree/report/templatetags/report.py b/InvenTree/report/templatetags/report.py
index 45d11c1d2d..9593db1885 100644
--- a/InvenTree/report/templatetags/report.py
+++ b/InvenTree/report/templatetags/report.py
@@ -14,6 +14,8 @@ from stock.models import StockItem
 
 from common.models import InvenTreeSetting
 
+import InvenTree.helpers
+
 register = template.Library()
 
 
@@ -119,18 +121,10 @@ def internal_link(link, text):
 
     text = str(text)
 
-    base_url = InvenTreeSetting.get_setting('INVENTREE_BASE_URL')
+    url = InvenTree.helpers.construct_absolute_url(link)
 
     # If the base URL is not set, just return the text
-    if not base_url:
+    if not url:
         return text
 
-    if not base_url.endswith('/'):
-        base_url += '/'
-
-    if base_url.endswith('/') and link.startswith('/'):
-        link = link[1:]
-
-    url = f"{base_url}{link}"
-
     return mark_safe(f'<a href="{url}">{text}</a>')