Initial CMocka testing against web_client.c (issue #7229). (#7264)

* Start of unit-test for http request processing.

A CMocka test-driver has been added to replay the live-capture headers against the http request processing code. Enough stubs / mocking code have been written to check that we can inject a chosen raw request into the web_client code and check how it was processed. A parameterised buffer building function can setup requests for testing in `web_buffer` structures. Each endpoint in the API will be checked against a variety of http requests. This PoC demonstrates enough functionality to show building the request on demand for each test-case and cleaning up afterwards. 

1 files changed, 168 insertions, 0 deletions

diff --git a/web/api/tests/web_api.c b/web/api/tests/web_api.c
new file mode 100644
index 0000000000..77d3458de4
--- /dev/null
+++ b/web/api/tests/web_api.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "../../../libnetdata/libnetdata.h"
+#include "../../../libnetdata/required_dummies.h"
+#include "../../../database/rrd.h"
+#include "../../../web/server/web_client.h"
+#include <setjmp.h>
+#include <cmocka.h>
+#include <stdbool.h>
+
+RRDHOST *__wrap_rrdhost_find_by_hostname(const char *hostname, uint32_t hash)
+{
+    return NULL;
+}
+
+/* Note: we've got some intricate code inside the global statistics module, might be useful to pull it inside the
+         test set instead of mocking it. */
+void __wrap_finished_web_request_statistics(
+    uint64_t dt, uint64_t bytes_received, uint64_t bytes_sent, uint64_t content_size, uint64_t compressed_content_size)
+{
+}
+
+char *__wrap_config_get(struct config *root, const char *section, const char *name, const char *default_value)
+{
+    if (!strcmp(section, CONFIG_SECTION_WEB) && !strcmp(name, "web files owner"))
+        return "netdata";
+    return "UNKNOWN FIX ME";
+}
+
+int __wrap_web_client_api_request_v1(RRDHOST *host, struct web_client *w, char *url)
+{
+    printf("api requests: %s\n", url);
+}
+
+int __wrap_rrdpush_receiver_thread_spawn(RRDHOST *host, struct web_client *w, char *url)
+{
+    return 0;
+}
+
+RRDHOST *__wrap_rrdhost_find_by_guid(const char *guid, uint32_t hash)
+{
+    printf("FIXME: rrdset_find_guid\n");
+    return NULL;
+}
+
+RRDSET *__wrap_rrdset_find_byname(RRDHOST *host, const char *name)
+{
+    printf("FIXME: rrdset_find_byname\n");
+    return NULL;
+}
+
+RRDSET *__wrap_rrdset_find(RRDHOST *host, const char *id)
+{
+    printf("FIXME: rrdset_find\n");
+    return NULL;
+}
+
+void __wrap_debug_int(const char *file, const char *function, const unsigned long line, const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    printf("DEBUG: ");
+    vprintf(fmt, args);
+    printf("\n");
+    va_end(args);
+}
+
+void __wrap_info_int(const char *file, const char *function, const unsigned long line, const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    printf("INFO: ");
+    vprintf(fmt, args);
+    printf("\n");
+    va_end(args);
+}
+
+void __wrap_error_int(
+    const char *prefix, const char *file, const char *function, const unsigned long line, const char *fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    printf("ERROR: ");
+    vprintf(fmt, args);
+    printf("\n");
+    va_end(args);
+}
+
+WEB_SERVER_MODE web_server_mode = WEB_SERVER_MODE_STATIC_THREADED;
+char *netdata_configured_web_dir = "UNKNOWN FIXME";
+RRDHOST *localhost = NULL;
+
+struct config netdata_config = { .sections = NULL,
+                                 .mutex = NETDATA_MUTEX_INITIALIZER,
+                                 .index = { .avl_tree = { .root = NULL, .compar = appconfig_section_compare },
+                                            .rwlock = AVL_LOCK_INITIALIZER } };
+
+const char *http_headers[] = { "Host: 254.254.0.1",
+                               "User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_" // No ,
+                               "0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.70 Safari/537.36",
+                               "Connection: keep-alive",
+                               "X-Forwarded-For: 1.254.1.251",
+                               "Cookie: _ga=GA1.1.1227576758.1571113676; _gid=GA1.2.1222321739.1573628979",
+                               "X-Requested-With: XMLHttpRequest",
+                               "Accept-Encoding: gzip, deflate",
+                               "Cache-Control: no-cache, no-store" };
+#define MAX_HEADERS (sizeof(http_headers) / (sizeof(const char *)))
+
+static void build_request(struct web_buffer *wb, const char *url, bool use_cr, size_t num_headers)
+{
+    buffer_reset(wb);
+    buffer_strcat(wb, "GET ");
+    buffer_strcat(wb, url);
+    buffer_strcat(wb, " HTTP/1.1");
+    if (use_cr)
+        buffer_strcat(wb, "\r");
+    buffer_strcat(wb, "\n");
+    for (size_t i = 0; i < num_headers && i < MAX_HEADERS; i++) {
+        buffer_strcat(wb, http_headers[i]);
+        if (use_cr)
+            buffer_strcat(wb, "\r");
+        buffer_strcat(wb, "\n");
+    }
+    if (use_cr)
+        buffer_strcat(wb, "\r");
+    buffer_strcat(wb, "\n");
+}
+
+static struct web_client *pre_test_setup()
+{
+    localhost = malloc(sizeof(RRDHOST));
+    struct web_client *w = (struct web_client *)malloc(sizeof(struct web_client));
+    w->response.data = buffer_create(NETDATA_WEB_RESPONSE_INITIAL_SIZE);
+    w->response.header = buffer_create(NETDATA_WEB_RESPONSE_HEADER_SIZE);
+    w->response.header_output = buffer_create(NETDATA_WEB_RESPONSE_HEADER_SIZE);
+    strcpy(w->origin, "*"); // Simulate web_client_create_on_fd()
+    w->cookie1[0] = 0;      // Simulate web_client_create_on_fd()
+    w->cookie2[0] = 0;      // Simulate web_client_create_on_fd()
+    return w;
+}
+
+static void post_test_cleanup(struct web_client *w)
+{
+    buffer_free(w->response.data);
+    buffer_free(w->response.header);
+    buffer_free(w->response.header_output);
+    free(w);
+    free(localhost);
+}
+
+static void api_info(void **state)
+{
+    for (size_t i = 0; i < MAX_HEADERS; i++) {
+        struct web_client *w = pre_test_setup();
+        build_request(w->response.data, "/api/v1/info", true, i);
+        web_client_process_request(w);
+        assert_int_equal(w->flags & WEB_CLIENT_FLAG_WAIT_RECEIVE, 0);
+        post_test_cleanup(w);
+    }
+}
+
+int main(void)
+{
+    const struct CMUnitTest tests[] = { cmocka_unit_test(api_info) };
+    debug_flags = 0xffffffffffff;
+
+    return cmocka_run_group_tests_name("web_api", tests, NULL, NULL);
+}