feat(server): add utm parameter parser

Author: JeanMeijer

packages/analytics/src/server/utm.ts

@@ -0,0 +1,39 @@
+const UTM_PARAMS = ["source", "medium", "content", "term", "campaign"] as const;
+
+function parseUtmParameter(name: string, strictUtm: boolean) {
+  if (strictUtm) {
+    return UTM_PARAMS.find((param) => name === `utm_${param}`);
+  }
+
+  if (name === "ref") {
+    return "source";
+  }
+
+  return UTM_PARAMS.find((param) => name === `utm_${param}` || name === param);
+}
+
+interface UtmOptions {
+  strictUtm: boolean;
+}
+
+interface UtmParameters {
+  source?: string | undefined;
+  campaign?: string | undefined;
+  medium?: string | undefined;
+  content?: string | undefined;
+  term?: string | undefined;
+}
+
+export function parseUtmParameters(searchParams: URLSearchParams, options: UtmOptions) {
+  const params: UtmParameters = {};
+
+  for (const [name, value] of searchParams.entries()) {
+    const param = parseUtmParameter(name, options.strictUtm);
+
+    if (param) {
+      params[param] = value;
+    }
+  }
+
+  return params;
+}