docker.cpp

#include "docker.h"


size_t writeFunction(void *ptr, size_t size, size_t nmemb, string *data){
    // Simple callback for response of curl
    data->append((char *)ptr, size * nmemb);
    return size * nmemb;
}
string convert_http_query(string str){
    // Process http query to use it with curl
    string::size_type pos = 0;
    while ((pos = str.find(' ', pos)) != string::npos){
        str.replace(pos, 1, "%20");
        pos += 3;
    }

    return str;
}

string raw_request(string endpoint, int method, string data, string docker_socket){
    /* Raw request to docker endpoint
        Choose docker socket
        Choose http host
        Choose http request type (GET, POST) */

    string url = convert_http_query(endpoint);
    string response_string;
    string header_string;
    long http_code = 0;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    auto curl = curl_easy_init();
    if (curl){
        // Convert socket path + endpoint from string to *char
        int endpoint_length = endpoint.length();
        char endpoint_arr[endpoint_length + 1];
        strcpy(endpoint_arr, endpoint.c_str());
        int socket_length = docker_socket.length();
        char socket_arr[socket_length + 1];
        strcpy(socket_arr, docker_socket.c_str());

        curl_easy_setopt(curl, CURLOPT_UNIX_SOCKET_PATH, socket_arr);
        curl_easy_setopt(curl, CURLOPT_URL, endpoint_arr);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeFunction);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response_string);
        curl_easy_setopt(curl, CURLOPT_HEADERDATA, &header_string);

        if (method == 1){ // POST
            struct curl_slist *hs = NULL;
            hs = curl_slist_append(hs, "Content-Type: application/json");
            curl_easy_setopt(curl, CURLOPT_HTTPHEADER, hs);
            curl_easy_setopt(curl, CURLOPT_POSTFIELDS, data.c_str());
        }
        else if (method == 2){} // PUT
        else if (method == 3){ //DELETE
            curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "DELETE");
        }

        curl_easy_perform(curl);
        curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &http_code);
        curl_easy_cleanup(curl);
        curl_global_cleanup();
        curl = NULL;
    }
    return response_string;
}

json raw_api(string endpoint, int method, string data, bool plain, string docker_socket){
    string plain_text = raw_request(endpoint, method, data);
    if (plain) return {{"data", plain_text}};
    json no_data = {{"data", false}};
    if (plain_text.length() == 0)
        return no_data;
    else
        return json::parse(plain_text);
}

json list_containers(bool all, string host){
    string endpoint = host + "/containers/json?all=" + to_string(all);
    return raw_api(endpoint);
}

json inspect_container(string id, string host){
    string endpoint = host + "/containers/" + id + "/json";
    return raw_api(endpoint);
}
json processes_in_container(string id, string ps_args, string host){
    string endpoint = host + "/containers/" + id + "/top?ps_args=" + ps_args;
    return raw_api(endpoint);
}

json start_container(string id, string host){
    string endpoint = host + "/containers/" + id + "/start";
    return raw_api(endpoint, 1);
}

json stop_container(string id, int t, string host){
    string endpoint = host + "/containers/" + id + "/stop?=" + to_string(t);
    return raw_api(endpoint, 1);
}

json restart_container(string id, int t, string host){
    string endpoint = host + "/containers/" + id + "/restart?t=" + to_string(t);
    return raw_api(endpoint, 1);
}

json kill_container(string id, string signal, string host){
    string endpoint = host + "/containers/" + id + "/kill?signal=" + signal;
    return raw_api(endpoint, 1);
}

json exec_in_container(string id, string bash_command, bool bash, bool AttachStdin, bool AttachStdout, bool AttachStderr, bool tty, string working_dir, string host){
    // Creating exec instance
    
    string endpoint = host + "/containers/" + id + "/exec";

    json payload = {
        {"AttachStdin", AttachStdin},
        {"AttachStdout", AttachStdout},
        {"AttachStderr", AttachStderr},
        {"Tty", tty},
        {"WorkingDir", working_dir}};
    // To execute bash command in docker, you need to use smth, like bash -c COMMAND HERE
    // To execute binary in docker, you need to use smth, like /path/to/bin
    if (bash)
        payload["Cmd"] = {"bash", "-c", bash_command};
    else
        payload["Cmd"] = {bash_command};
    string payload_string = payload.dump();
    printf("%s\n", payload_string.c_str());
    json res = raw_api(endpoint, 1, payload_string);
    // Start exec instance
    payload = {
        {"Detach", true},
        {"Tty", true}};
    payload_string = payload.dump();
    
    return raw_api((host + "/exec/" + string(res["Id"]) + "/start"), 1, payload_string);
}

json create_container(string image, int StopTimeout, json volumes, int MemoryLimit, string bash_init_cmd, string WorkingDir, bool AttachStdin, bool AttachStdout, bool AttachStderr, bool NetworkDisabled, string host){
    json payload = {
        {"Image", image},
        {"Cmd", {"ls", "/home/code"}},
        {"HostConfig", {{"Memory", MemoryLimit}, {"Mounts", {{{"Target", "/home/code"}, {"Source", "workspace/tmp"}, {"Type", "volume"}, {"ReadOnly", false}}}}}},
        {"NetworkDisabled", NetworkDisabled},
        {"WorkingDir", WorkingDir},
    };
    string payload_string = payload.dump();
    printf("\n%s\n", payload_string.c_str());

    string endpoint = host + "/containers/create";
    return raw_api(endpoint, 1, payload_string);
}

string get_container_logs(string id, bool stream_stdout, bool stream_stderr, string host){
    string endpoint = host + "/containers/" + id + "/logs?stdout=" + to_string(stream_stdout) + "&stderr=" + to_string(stream_stderr);
    return raw_api(endpoint, 0, "", true)["data"];
}
json wait_for_container(string id, string host){
    // Yeah, we will stack here
    string endpoint = host + "/containers/" + id + "/wait";
    json res = raw_api(endpoint, 1, "");
    return res;
}
json remove_container(string id, string host){
    string endpoint = host + "/containers/" + id;
    return raw_api(endpoint, 3);
}