Add removeallquerystring function (#13)

Author: duffn

README.md

@@ -43,7 +43,7 @@ set req.url = querymodifier.excludparams(url=req.url, params="ts,v");
 # Modified URL: example.com/?search=name&id=987654321
 ```
 
-### Remove all
+### Remove all valid query parameters
 
 Remove all query parameters by passing in an empty string.
 
@@ -57,6 +57,19 @@ set req.url = querymodifier.modifyparams(url=req.url, params="", exclude_params=
 # Modified URL: example.com/
 ```
 
+### Remove all query string
+
+Remove all  of the query string, i.e. everything after, and including the `?` regardless of if
+the are valid `name=value` query string parameters.
+
+```
+import querymodifier;
+set req.url = querymodifier.removeallquerystring(url=req.url);
+
+# Original URL: example.com/?123456
+# Modified URL: example.com/
+```
+
 ### Additional
 
 See the tests for more parameter edge cases.

src/vmod_querymodifier.c

@@ -309,3 +309,34 @@ VCL_STRING
 vmod_excludeallparams(VRT_CTX, VCL_STRING uri) {
     return vmod_modifyparams(ctx, uri, NULL, 1);
 }
+
+/**
+ * Remove the entire query string from the URL, regardless of its content.
+ * This function will remove everything after (and including) the '?'.
+ * @param ctx The Varnish context.
+ * @param uri The URL to modify.
+ * @return The URL without any query parameters.
+ */
+VCL_STRING
+vmod_removeallquerystring(VRT_CTX, VCL_STRING uri) {
+    CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
+    CHECK_OBJ_NOTNULL(ctx->ws, WS_MAGIC);
+
+    if (uri == NULL) {
+        VRT_fail(ctx, "uri is NULL");
+        return NULL;
+    }
+
+    char *uri_buf = WS_Copy(ctx->ws, uri, strlen(uri) + 1);
+    if (!uri_buf) {
+        VRT_fail(ctx, "WS_Copy: uri_buf: out of workspace");
+        return NULL;
+    }
+
+    char *query = strchr(uri_buf, '?');
+    if (query != NULL) {
+        *query = '\0';
+    }
+
+    return uri_buf;
+}

src/vmod_querymodifier.vcc

@@ -48,3 +48,13 @@ Example
     ::
 
         set req.url = querymodifier.excludeallparams(req.url);
+
+$Function STRING removeallquerystring(STRING url)
+
+Description
+    The function removes the entire query string from the URL, i.e. everything after and including the '?'.
+
+Example
+    ::
+
+        set req.url = querymodifier.removeallquerystring(req.url);

src/vtc/removeallquerystring.vtc

@@ -0,0 +1,38 @@
+varnishtest "Test querymodifier vmod for proper removal of all query parameters"
+
+server s1 {
+	rxreq
+	txresp -body "OK1"
+	expect req.url == "/feed/"
+
+	rxreq
+	txresp -body "OK1"
+	expect req.url == "/feed/"
+} -start
+
+varnish v1 -vcl+backend {
+	import std;
+	import querymodifier;
+
+	sub vcl_hash {
+		std.syslog(180, "querymodifier before: " + req.url);
+		set req.url = querymodifier.removeallquerystring(url=req.url);
+		std.syslog(180, "querymodifier after: " + req.url);
+	}
+} -start
+
+client c1 {
+	txreq -url "/feed/?1730210988319&ts=1730210988319"
+	rxresp
+	expect resp.status == 200
+
+	# This one will be cached as all of the query params are excluded, even invalid ones.
+	txreq -url "/feed/?1730210982229"
+	rxresp
+	expect resp.status == 200
+} -run
+
+varnish v1 -expect n_object == 1
+varnish v1 -expect cache_miss == 1
+varnish v1 -expect cache_hit == 1
+