From da6de4ce90065927b0adc0db34145c8754c253cc Mon Sep 17 00:00:00 2001
From: Mathew Tonkin Henwood <7479946+mathewTH@users.noreply.github.com>
Date: Thu, 5 Jan 2023 18:06:39 +1300
Subject: [PATCH] Add FieldNameTag config

Allows field names to be based on a different tag.
Json is still the default tag so this is not a breaking change.
https://github.com/invopop/jsonschema/discussions/28#discussioncomment-4387240
---
 reflect.go | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/reflect.go b/reflect.go
index 6ebc6be..399c2ff 100644
--- a/reflect.go
+++ b/reflect.go
@@ -183,6 +183,9 @@ type Reflector struct {
 	// root as opposed to a definition with a reference.
 	ExpandedStruct bool
 
+	// FieldNameTag will change the tag used to get field names. json tags are used by default.
+	FieldNameTag string
+
 	// IgnoredTypes defines a slice of types that should be ignored in the schema,
 	// switching to just allowing additional properties instead.
 	IgnoredTypes []interface{}
@@ -989,7 +992,11 @@ func ignoredByJSONSchemaTags(tags []string) bool {
 }
 
 func (r *Reflector) reflectFieldName(f reflect.StructField) (string, bool, bool, bool) {
-	jsonTagString, _ := f.Tag.Lookup("json")
+	tagKey := r.FieldNameTag
+	if tagKey == "" {
+		tagKey = "json"
+	}
+	jsonTagString := f.Tag.Get(tagKey)
 	jsonTags := strings.Split(jsonTagString, ",")
 
 	if ignoredByJSONTags(jsonTags) {