[njs] HTTP: expose capture group variables.

[noreply at nginx.com]

details:   https://github.com/nginx/njs/commit/8553c2a6a2cb0c7bdd111f5b1799aaba8004eba6
branches:  master
commit:    8553c2a6a2cb0c7bdd111f5b1799aaba8004eba6
user:      Thomas P. <TPXP at users.noreply.github.com>
date:      Tue, 30 Jul 2024 18:03:34 +0200
description:
HTTP: expose capture group variables.


---
 nginx/ngx_http_js_module.c     |  29 +++++++++++-
 nginx/t/js_capture_variables.t | 101 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 128 insertions(+), 2 deletions(-)

diff --git a/nginx/ngx_http_js_module.c b/nginx/ngx_http_js_module.c
index 86d907df..824b647c 100644
--- a/nginx/ngx_http_js_module.c
+++ b/nginx/ngx_http_js_module.c
@@ -2954,10 +2954,10 @@ static njs_int_t
 ngx_http_js_request_variables(njs_vm_t *vm, njs_object_prop_t *prop,
     ngx_http_request_t *r, njs_value_t *setval, njs_value_t *retval)
 {
-    njs_int_t                   rc;
+    njs_int_t                   rc, is_capture, start, length;
     njs_str_t                   val, s;
     ngx_str_t                   name;
-    ngx_uint_t                  key;
+    ngx_uint_t                  i, key;
     ngx_http_variable_t        *v;
     ngx_http_core_main_conf_t  *cmcf;
     ngx_http_variable_value_t  *vv;
@@ -2972,6 +2972,31 @@ ngx_http_js_request_variables(njs_vm_t *vm, njs_object_prop_t *prop,
     name.len = val.length;
 
     if (setval == NULL) {
+        is_capture = 1;
+        for (i = 0; i < name.len; i++) {
+            if (name.data[i] < '0' || name.data[i] > '9') {
+                is_capture = 0;
+                break;
+            }
+        }
+
+        if (is_capture) {
+            key = ngx_atoi(name.data, name.len) * 2;
+            if (r->captures == NULL || r->captures_data == NULL
+                || r->ncaptures <= key)
+            {
+                njs_value_undefined_set(retval);
+                return NJS_DECLINED;
+            }
+
+            start = r->captures[key];
+            length = r->captures[key + 1] - start;
+
+            return ngx_js_prop(vm, njs_vm_prop_magic32(prop), retval,
+                               &r->captures_data[start], length);
+        }
+
+        /* Lookup the variable in nginx variables */
         key = ngx_hash_strlow(name.data, name.data, name.len);
 
         vv = ngx_http_get_variable(r, &name, key);
diff --git a/nginx/t/js_capture_variables.t b/nginx/t/js_capture_variables.t
new file mode 100644
index 00000000..ccc977ee
--- /dev/null
+++ b/nginx/t/js_capture_variables.t
@@ -0,0 +1,101 @@
+#!/usr/bin/perl
+
+# (C) Thomas P.
+
+# Tests for http njs module, reading location capture variables.
+
+###############################################################################
+
+use warnings;
+use strict;
+
+use Test::More;
+
+BEGIN { use FindBin; chdir($FindBin::Bin); }
+
+use lib 'lib';
+use Test::Nginx;
+
+###############################################################################
+
+select STDERR; $| = 1;
+select STDOUT; $| = 1;
+
+my $t = Test::Nginx->new()->has(qw/http/)
+	->write_file_expand('nginx.conf', <<'EOF');
+
+%%TEST_GLOBALS%%
+
+daemon off;
+
+events {
+}
+
+http {
+    %%TEST_GLOBALS_HTTP%%
+
+    js_import test.js;
+
+    server {
+        listen       127.0.0.1:8080;
+        server_name  localhost;
+
+        location /njs {
+            js_content test.njs;
+        }
+
+        location ~ /(.+)/(.+) {
+            js_content test.variables;
+        }
+    }
+}
+
+EOF
+
+$t->write_file('test.js', <<EOF);
+    function variables(r) {
+        return r.return(200, `"\${r.variables[r.args.index]}"`);
+    }
+
+    function test_njs(r) {
+        r.return(200, njs.version);
+    }
+
+    export default {njs:test_njs, variables};
+
+EOF
+
+$t->try_run('no njs capture variables')->plan(4);
+
+###############################################################################
+
+TODO: {
+local $TODO = 'not yet' unless has_version('0.8.6');
+
+like(http_get('/test/hello?index=0'), qr/"\/test\/hello"/, 'global capture');
+like(http_get('/test/hello?index=1'), qr/"test"/, 'local capture 1');
+like(http_get('/test/hello?index=2'), qr/"hello"/, 'local capture 2');
+like(http_get('/test/hello?index=3'), qr/"undefined"/, 'undefined capture');
+
+}
+
+###############################################################################
+
+sub has_version {
+	my $need = shift;
+
+	http_get('/njs') =~ /^([.0-9]+)$/m;
+
+	my @v = split(/\./, $1);
+	my ($n, $v);
+
+	for $n (split(/\./, $need)) {
+		$v = shift @v || 0;
+		return 0 if $n > $v;
+		return 1 if $v > $n;
+	}
+
+	return 1;
+}
+
+###############################################################################