Add HPC support. Developed by Tuoxing Liu; initial hyperqueue support…

… by Lev Gromov

hpc/LoadBalancer.cpp

@@ -0,0 +1,71 @@
+#include "LoadBalancer.hpp"
+#include <iostream>
+#include <string>
+#include <chrono>
+#include <thread>
+#include <filesystem>
+
+#include <unistd.h>
+#include <limits.h>
+
+#include "lib/umbridge.h"
+
+void create_directory_if_not_existing(std::string directory) {
+    if (!std::filesystem::is_directory(directory) || !std::filesystem::exists(directory)) {
+        std::filesystem::create_directory(directory);
+    }
+}
+
+std::string get_hostname() {
+    char hostname[HOST_NAME_MAX];
+    gethostname(hostname, HOST_NAME_MAX);
+    return std::string(hostname);
+}
+
+int main(int argc, char *argv[])
+{
+
+    create_directory_if_not_existing("urls");
+    create_directory_if_not_existing("sub-jobs");
+
+    // Read environment variables for configuration
+    char const *port_cstr = std::getenv("PORT");
+    int port = 0;
+    if (port_cstr == NULL)
+    {
+        std::cout << "Environment variable PORT not set! Using port 4242 as default." << std::endl;
+        port = 4242;
+    }
+    else
+    {
+        port = atoi(port_cstr);
+    }
+
+    // Start: Instaltialize multiple LB classes for multiple models on the regular server
+
+    // start a SLURM job for single request
+    const std::string job_id = submitJob("sbatch model.slurm");
+    const std::string server_url = readUrl("./urls/url-" + job_id + ".txt"); // read server url from txt file
+    // May use $SLURM_LOCALID in a .slurm file later
+    std::cout << "Hosting sub-server at : " << server_url << std::endl;
+    // List supported models
+    std::vector<std::string> model_names = umbridge::SupportedModels(server_url);
+
+    std::vector<LoadBalancer> LB_vector;
+    for (auto model_name : model_names)
+    {
+        // Set up and serve model
+        LB_vector.emplace_back(LoadBalancer{model_name});
+    }
+
+    // End: Instaltialize multiple LB classes for multiple models on the regular server
+
+    // Create a new vector of pointers to LB_vector
+    std::vector<umbridge::Model *> LB_ptr_vector(LB_vector.size());
+    std::transform(LB_vector.begin(), LB_vector.end(), LB_ptr_vector.begin(),
+                   [](LoadBalancer& obj) { return &obj; });
+
+    std::cout << "Load balancer running on host " << get_hostname()
+              << " and bound to 0.0.0.0:" << port << std::endl;
+    umbridge::serveModels(LB_ptr_vector, "0.0.0.0", port, false);
+}