1 files changed, 76 insertions, 0 deletions
diff --git a/logforwarder/src/apps/vespa-otelcol-start/wrapper.cpp b/logforwarder/src/apps/vespa-otelcol-start/wrapper.cpp
new file mode 100644
index 00000000000..7228a3ea921
--- /dev/null
+++ b/logforwarder/src/apps/vespa-otelcol-start/wrapper.cpp
@@ -0,0 +1,76 @@
+// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "wrapper.h"
+#include "child-handler.h"
+
+#include <dirent.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <vespa/defaults.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".wrapper");
+
+namespace {
+
+vespalib::string fixDir(const vespalib::string &parent, const vespalib::string &subdir) {
+    auto dirname = parent + "/" + subdir;
+    DIR *dp = opendir(dirname.c_str());
+    if (dp == NULL) {
+        if (errno != ENOENT || mkdir(dirname.c_str(), 0755) != 0) {
+            LOG(warning, "Could not create directory '%s'", dirname.c_str());
+            perror(dirname.c_str());
+        }
+    } else {
+        closedir(dp);
+    }
+    return dirname;
+}
+
+vespalib::string cfFilePath() {
+    vespalib::string path = vespa::Defaults::underVespaHome("var/db/vespa");
+    path = fixDir(path, "otelcol");
+    return path + "/" + "config.yaml";
+}
+
+void  writeConfig(const vespalib::string &config, const vespalib::string &path) {
+    LOG(info, "got config, writing %s", path.c_str());
+    vespalib::string tmpPath = path + ".new";
+    FILE *fp = fopen(tmpPath.c_str(), "w");
+    if (fp == NULL) {
+        LOG(warning, "could not open '%s' for write", tmpPath.c_str());
+        return;
+    }
+    fprintf(fp, "%s\n", config.c_str());
+    fclose(fp);
+    rename(tmpPath.c_str(), path.c_str());
+}
+
+} // namespace <unnamed>
+
+Wrapper::Wrapper(const std::string &configId)
+  : CfHandler(configId),
+    _childHandler()
+{}
+
+Wrapper::~Wrapper() = default;
+
+void Wrapper::stop() {
+    _childHandler.stopChild();
+}
+
+void Wrapper::check() {
+    checkConfig();
+    if (_childHandler.checkChild()) {
+        LOG(error, "Fatal: child process died unexpectedly");
+        std::_Exit(EXIT_FAILURE);
+    }
+}
+
+void Wrapper::gotConfig(const OpenTelemetryConfig& config) {
+    _childHandler.stopChild();
+    std::string progPath = vespa::Defaults::underVespaHome("sbin/otelcol-contrib");
+    std::string cfPath = cfFilePath();
+    writeConfig(config.yaml, cfPath);
+    _childHandler.startChild(progPath, cfPath);
+}