test: Metrics tests for lib/ and feature/

Related to #40063

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/test/include.am

@@ -200,6 +200,7 @@ src_test_test_SOURCES += \
 	src/test/test_link_handshake.c \
 	src/test/test_logging.c \
 	src/test/test_mainloop.c \
+	src/test/test_metrics.c \
 	src/test/test_microdesc.c \
 	src/test/test_namemap.c \
 	src/test/test_netinfo.c \

src/test/test.c

@@ -738,6 +738,7 @@ struct testgroup_t testgroups[] = {
   { "legacy_hs/", hs_tests },
   { "link-handshake/", link_handshake_tests },
   { "mainloop/", mainloop_tests },
+  { "metrics/", metrics_tests },
   { "netinfo/", netinfo_tests },
   { "nodelist/", nodelist_tests },
   { "oom/", oom_tests },

src/test/test.h

@@ -150,6 +150,7 @@ extern struct testcase_t keypin_tests[];
 extern struct testcase_t link_handshake_tests[];
 extern struct testcase_t logging_tests[];
 extern struct testcase_t mainloop_tests[];
+extern struct testcase_t metrics_tests[];
 extern struct testcase_t microdesc_tests[];
 extern struct testcase_t namemap_tests[];
 extern struct testcase_t netinfo_tests[];

src/test/test_metrics.c

@@ -0,0 +1,254 @@
+/* Copyright (c) 2020, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/**
+ * \file test_metrics.c
+ * \brief Test lib/metrics and feature/metrics functionnalities
+ */
+
+#define CONFIG_PRIVATE
+#define CONNECTION_PRIVATE
+#define METRICS_STORE_ENTRY_PRIVATE
+
+#include "test/test.h"
+#include "test/test_helpers.h"
+#include "test/log_test_helpers.h"
+
+#include "app/config/config.h"
+
+#include "core/mainloop/connection.h"
+#include "core/or/connection_st.h"
+#include "core/or/policies.h"
+#include "core/or/port_cfg_st.h"
+
+#include "feature/metrics/metrics.h"
+
+#include "lib/encoding/confline.h"
+#include "lib/metrics/metrics_store.h"
+
+#define TEST_METRICS_ENTRY_NAME    "entryA"
+#define TEST_METRICS_ENTRY_HELP    "Description of entryA"
+#define TEST_METRICS_ENTRY_LABEL_1 "label=farfadet"
+#define TEST_METRICS_ENTRY_LABEL_2 "label=ponki"
+
+static void
+set_metrics_port(or_options_t *options)
+{
+  const char *port = "MetricsPort 9035"; /* Default to 127.0.0.1 */
+  const char *policy = "MetricsPortPolicy accept 1.2.3.4";
+
+  config_get_lines(port, &options->MetricsPort_lines, 0);
+  config_get_lines(policy, &options->MetricsPortPolicy, 0);
+
+  /* Parse and validate policy. */
+  policies_parse_from_options(options);
+}
+
+static void
+test_config(void *arg)
+{
+  char *err_msg = NULL;
+  tor_addr_t addr;
+  smartlist_t *ports = smartlist_new();
+  or_options_t *options = get_options_mutable();
+
+  (void) arg;
+
+  set_metrics_port(options);
+
+  int ret = metrics_parse_ports(options, ports, &err_msg);
+  tt_int_op(ret, OP_EQ, 0);
+  tt_int_op(smartlist_len(ports), OP_EQ, 1);
+
+  /* Validate the configured port. */
+  const port_cfg_t *cfg = smartlist_get(ports, 0);
+  tt_assert(tor_addr_eq_ipv4h(&cfg->addr, 0x7f000001));
+  tt_int_op(cfg->port, OP_EQ, 9035);
+  tt_int_op(cfg->type, OP_EQ, CONN_TYPE_METRICS_LISTENER);
+
+  /* Address of the policy should be permitted. */
+  tor_addr_from_ipv4h(&addr, 0x01020304); /* 1.2.3.4 */
+  ret = metrics_policy_permits_address(&addr);
+  tt_int_op(ret, OP_EQ, true);
+
+  /* Anything else, should not. */
+  tor_addr_from_ipv4h(&addr, 0x01020305); /* 1.2.3.5 */
+  ret = metrics_policy_permits_address(&addr);
+  tt_int_op(ret, OP_EQ, false);
+
+ done:
+  SMARTLIST_FOREACH(ports, port_cfg_t *, c, port_cfg_free(c));
+  smartlist_free(ports);
+  or_options_free(options);
+}
+
+static char _c_buf[256];
+#define CONTAINS(conn, msg) \
+  do { \
+    tt_int_op(buf_datalen(conn->outbuf), OP_EQ, (strlen(msg))); \
+    memset(_c_buf, 0, sizeof(_c_buf)); \
+    buf_get_bytes(conn->outbuf, _c_buf, (strlen(msg))); \
+    tt_str_op(_c_buf, OP_EQ, (msg)); \
+    tt_int_op(buf_datalen(conn->outbuf), OP_EQ, 0); \
+  } while (0)
+
+#define WRITE(conn, msg) \
+  buf_add(conn->inbuf, (msg), (strlen(msg)));
+
+static void
+test_connection(void *arg)
+{
+  int ret;
+  connection_t *conn = connection_new(CONN_TYPE_METRICS, AF_INET);
+  or_options_t *options = get_options_mutable();
+
+  (void) arg;
+
+  /* Setup policy. */
+  set_metrics_port(options);
+
+  /* Set 1.2.3.5 IP, we should get rejected. */
+  tor_addr_from_ipv4h(&conn->addr, 0x01020305);
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, -1);
+
+  /* Set 1.2.3.4 so from now on we are allowed to process the inbuf. */
+  tor_addr_from_ipv4h(&conn->addr, 0x01020304);
+
+  /* No HTTP request yet. */
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, -1);
+
+  /* Bad request. */
+  WRITE(conn, "HTTP 4.7\r\n\r\n");
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, -1);
+  CONTAINS(conn, "HTTP/1.0 400 Bad Request\r\n\r\n");
+
+  /* Path not found. */
+  WRITE(conn, "GET /badpath HTTP/1.0\r\n\r\n");
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, -1);
+  CONTAINS(conn, "HTTP/1.0 404 Not Found\r\n\r\n");
+
+  /* Method not allowed. */
+  WRITE(conn, "POST /something HTTP/1.0\r\n\r\n");
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, -1);
+  CONTAINS(conn, "HTTP/1.0 405 Method Not Allowed\r\n\r\n");
+
+  /* Ask for metrics. The content should be above 0. We don't test the
+   * validity of the returned content but it is certainly not an error. */
+  WRITE(conn, "GET /metrics HTTP/1.0\r\n\r\n");
+  ret = metrics_connection_process_inbuf(conn);
+  tt_int_op(ret, OP_EQ, 0);
+  tt_int_op(buf_datalen(conn->outbuf), OP_GT, 0);
+
+ done:
+  or_options_free(options);
+  connection_free_minimal(conn);
+}
+
+static void
+test_prometheus(void *arg)
+{
+  metrics_store_t *store = NULL;
+  metrics_store_entry_t *entry = NULL;
+  buf_t *buf = buf_new();
+  char *output = NULL;
+
+  (void) arg;
+
+  /* Fresh new store. No entries. */
+  store = metrics_store_new();
+  tt_assert(store);
+
+  /* Add entry and validate its content. */
+  entry = metrics_store_add(store, METRICS_TYPE_COUNTER,
+                            TEST_METRICS_ENTRY_NAME,
+                            TEST_METRICS_ENTRY_HELP);
+  tt_assert(entry);
+  metrics_store_entry_add_label(entry, TEST_METRICS_ENTRY_LABEL_1);
+
+  static const char *expected =
+    "# HELP " TEST_METRICS_ENTRY_NAME " " TEST_METRICS_ENTRY_HELP "\n"
+    "# TYPE " TEST_METRICS_ENTRY_NAME " counter\n"
+    TEST_METRICS_ENTRY_NAME "{" TEST_METRICS_ENTRY_LABEL_1 "} 0\n";
+
+  metrics_store_get_output(METRICS_FORMAT_PROMETHEUS, store, buf);
+  output = buf_extract(buf, NULL);
+  tt_str_op(expected, OP_EQ, output);
+
+ done:
+  buf_free(buf);
+  tor_free(output);
+  metrics_store_free(store);
+}
+
+static void
+test_store(void *arg)
+{
+  metrics_store_t *store = NULL;
+  metrics_store_entry_t *entry = NULL;
+
+  (void) arg;
+
+  /* Fresh new store. No entries. */
+  store = metrics_store_new();
+  tt_assert(store);
+  tt_assert(!metrics_store_get_all(store, TEST_METRICS_ENTRY_NAME));
+
+  /* Add entry and validate its content. */
+  entry = metrics_store_add(store, METRICS_TYPE_COUNTER,
+                            TEST_METRICS_ENTRY_NAME,
+                            TEST_METRICS_ENTRY_HELP);
+  tt_assert(entry);
+  tt_int_op(entry->type, OP_EQ, METRICS_TYPE_COUNTER);
+  tt_str_op(entry->name, OP_EQ, TEST_METRICS_ENTRY_NAME);
+  tt_str_op(entry->help, OP_EQ, TEST_METRICS_ENTRY_HELP);
+  tt_uint_op(entry->u.counter.value, OP_EQ, 0);
+
+  /* Access the entry. */
+  tt_assert(metrics_store_get_all(store, TEST_METRICS_ENTRY_NAME));
+
+  /* Add a label to the entry to make it unique. */
+  metrics_store_entry_add_label(entry, TEST_METRICS_ENTRY_LABEL_1);
+  tt_int_op(metrics_store_entry_has_label(entry, TEST_METRICS_ENTRY_LABEL_1),
+            OP_EQ, true);
+
+  /* Update entry's value. */
+  metrics_store_entry_update(entry, 42);
+  tt_int_op(metrics_store_entry_get_value(entry), OP_EQ, 42);
+  metrics_store_entry_update(entry, 42);
+  tt_int_op(metrics_store_entry_get_value(entry), OP_EQ, 84);
+  metrics_store_entry_reset(entry);
+  tt_int_op(metrics_store_entry_get_value(entry), OP_EQ, 0);
+
+  /* Add a new entry of same name but different label. */
+  /* Add entry and validate its content. */
+  entry = metrics_store_add(store, METRICS_TYPE_COUNTER,
+                            TEST_METRICS_ENTRY_NAME,
+                            TEST_METRICS_ENTRY_HELP);
+  tt_assert(entry);
+  metrics_store_entry_add_label(entry, TEST_METRICS_ENTRY_LABEL_2);
+
+  /* Make sure _both_ entires are there. */
+  const smartlist_t *entries =
+    metrics_store_get_all(store, TEST_METRICS_ENTRY_NAME);
+  tt_assert(entries);
+  tt_int_op(smartlist_len(entries), OP_EQ, 2);
+
+ done:
+  metrics_store_free(store);
+}
+
+struct testcase_t metrics_tests[] = {
+
+  { "config", test_config, TT_FORK, NULL, NULL },
+  { "connection", test_connection, TT_FORK, NULL, NULL },
+  { "prometheus", test_prometheus, TT_FORK, NULL, NULL },
+  { "store", test_store, TT_FORK, NULL, NULL },
+
+  END_OF_TESTCASES
+};
+