Add basic test for the filesystem collector.

2 files changed, 122 insertions, 1 deletions

diff --git a/test/Makefile b/test/Makefile
index 8c92dae..0c3374a 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -12,7 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-COLLECTOR_TESTS := cpu diskstats
+COLLECTOR_TESTS := cpu diskstats filesystem
 
 COLLECTOR_TEST_PROGS := $(foreach c,$(COLLECTOR_TESTS),$(c)_test)
 COLLECTOR_TEST_OBJS := $(foreach p,$(COLLECTOR_TEST_PROGS),$(p).o)
diff --git a/test/filesystem_test.c b/test/filesystem_test.c
new file mode 100644
index 0000000..15aaa88
--- /dev/null
+++ b/test/filesystem_test.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright 2018 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <sys/statvfs.h>
+
+#include "harness.h"
+#include "mock_scrape.h"
+#include "../collector.h"
+
+extern const struct collector filesystem_collector;
+void filesystem_test_override_statvfs(void *ctx, int (*statvfs_func)(const char *path, struct statvfs *buf));
+
+static void mock_statvfs_clear(void);
+static void mock_statvfs_add(test_env *env, const char *path, struct statvfs *buf);
+static int mock_statvfs_func(const char *path, struct statvfs *buf);
+
+TEST(filesystem_metrics) {
+  test_write_file(
+      env,
+      "proc/mounts",
+      "/dev/mapper/vg00-root / ext4 rw,relatime,errors=remount-ro 0 0\n"
+      "/dev/sda1 /boot ext2 rw,noatime 0 0\n"
+      "/dev/mapper/fake /mnt/ro btrfs ro 0 0\n");
+  mock_statvfs_clear();
+  mock_statvfs_add(env, "/", &(struct statvfs){
+      .f_frsize = 512,
+      .f_blocks = 12345678, .f_bfree = 987654, .f_bavail = 876543,
+      .f_files = 123456, .f_ffree = 98765, .f_favail = 87654,
+      .f_flag = 0 });
+  mock_statvfs_add(env, "/boot", &(struct statvfs){
+      .f_frsize = 4096,
+      .f_blocks = 1234567, .f_bfree = 98765, .f_bavail = 87654,
+      .f_files = 12345, .f_ffree = 9876, .f_favail = 8765,
+      .f_flag = 0 });
+  mock_statvfs_add(env, "/mnt/ro", &(struct statvfs){
+      .f_frsize = 512,
+      .f_blocks = 2345678, .f_bfree = 87654, .f_bavail = 76543,
+      .f_files = 23456, .f_ffree = 8765, .f_favail = 7654,
+      .f_flag = ST_RDONLY });
+  scrape_req *req = mock_scrape_start(env);
+
+  void *ctx = filesystem_collector.init(0, 0);
+  filesystem_test_override_statvfs(ctx, mock_statvfs_func);
+  filesystem_collector.collect(req, ctx);
+
+  struct label *labels;
+  labels = LABEL_LIST({"device", "/dev/mapper/vg00-root"}, {"fstype", "ext4"}, {"mountpoint", "/"});
+  mock_scrape_expect(req, "node_filesystem_avail_bytes", labels, 448790016);
+  mock_scrape_expect(req, "node_filesystem_files", labels, 123456);
+  mock_scrape_expect(req, "node_filesystem_files_free", labels, 98765);
+  mock_scrape_expect(req, "node_filesystem_free_bytes", labels, 505678848);
+  mock_scrape_expect(req, "node_filesystem_readonly", labels, 0);
+  mock_scrape_expect(req, "node_filesystem_size_bytes", labels, 6320987136);
+  labels = LABEL_LIST({"device", "/dev/sda1"}, {"fstype", "ext2"}, {"mountpoint", "/boot"});
+  mock_scrape_expect(req, "node_filesystem_avail_bytes", labels, 359030784);
+  mock_scrape_expect(req, "node_filesystem_files", labels, 12345);
+  mock_scrape_expect(req, "node_filesystem_files_free", labels, 9876);
+  mock_scrape_expect(req, "node_filesystem_free_bytes", labels, 404541440);
+  mock_scrape_expect(req, "node_filesystem_readonly", labels, 0);
+  mock_scrape_expect(req, "node_filesystem_size_bytes", labels, 5056786432);
+  labels = LABEL_LIST({"device", "/dev/mapper/fake"}, {"fstype", "btrfs"}, {"mountpoint", "/mnt/ro"});
+  mock_scrape_expect(req, "node_filesystem_avail_bytes", labels, 39190016);
+  mock_scrape_expect(req, "node_filesystem_files", labels, 23456);
+  mock_scrape_expect(req, "node_filesystem_files_free", labels, 8765);
+  mock_scrape_expect(req, "node_filesystem_free_bytes", labels, 44878848);
+  mock_scrape_expect(req, "node_filesystem_readonly", labels, 1);
+  mock_scrape_expect(req, "node_filesystem_size_bytes", labels, 1200987136);
+  mock_scrape_expect_no_more(req);
+  mock_scrape_free(req);
+}
+
+TEST_SUITE {
+  TEST_SUITE_START;
+  RUN_TEST(filesystem_metrics);
+  TEST_SUITE_END;
+}
+
+// helpers for mocking statvfs calls
+
+#define MAX_STATVFS_MOCKS 16
+static struct { const char *path; struct statvfs buf; } mock_statvfs_data[MAX_STATVFS_MOCKS];
+static unsigned mock_statvfs_data_count = 0;
+
+static void mock_statvfs_clear(void) {
+  mock_statvfs_data_count = 0;
+}
+
+static void mock_statvfs_add(test_env *env, const char *path, struct statvfs *buf) {
+  if (mock_statvfs_data_count >= MAX_STATVFS_MOCKS)
+    test_fail(env, "too many statvfs(2) mocks");
+  mock_statvfs_data[mock_statvfs_data_count].path = path;
+  mock_statvfs_data[mock_statvfs_data_count].buf = *buf;
+  mock_statvfs_data_count++;
+}
+
+static int mock_statvfs_func(const char *path, struct statvfs *buf) {
+  for (unsigned i = 0; i < mock_statvfs_data_count; i++) {
+    if (strcmp(mock_statvfs_data[i].path, path) == 0) {
+      *buf = mock_statvfs_data[i].buf;
+      return 0;
+    }
+  }
+
+  errno = ENOENT;
+  return -1;
+}