server : refactor (#5882)

* server : refactoring (wip)

* server : remove llava/clip objects from build

* server : fix empty prompt handling + all slots idle logic

* server : normalize id vars

* server : code style

* server : simplify model chat template validation

* server : code style

* server : minor

* llama : llama_chat_apply_template support null buf

* server : do not process embedding requests when disabled

* server : reorganize structs and enums + naming fixes

* server : merge oai.hpp in utils.hpp

* server : refactor system prompt update at start

* server : disable cached prompts with self-extend

* server : do not process more than n_batch tokens per iter

* server: tests: embeddings use a real embeddings model (#5908)

* server, tests : bump batch to fit 1 embedding prompt

* server: tests: embeddings fix build type Debug is randomly failing (#5911)

* server: tests: embeddings, use different KV Cache size

* server: tests: embeddings, fixed prompt do not exceed n_batch, increase embedding timeout, reduce number of concurrent embeddings

* server: tests: embeddings, no need to wait for server idle as it can timout

* server: refactor: clean up http code (#5912)

* server : avoid n_available var

ggml-ci

* server: refactor: better http codes

* server : simplify json parsing + add comment about t_last

* server : rename server structs

* server : allow to override FQDN in tests

ggml-ci

* server : add comments

---------

Co-authored-by: Pierrick Hymbert <pierrick.hymbert@gmail.com>

1 files changed, 307 insertions, 396 deletions

diff --git a/examples/server/utils.hpp b/examples/server/utils.hpp
index b6e49d8b..df0a2778 100644
--- a/examples/server/utils.hpp
+++ b/examples/server/utils.hpp
@@ -1,15 +1,16 @@
 #pragma once
 
-#include <string>
-#include <vector>
-#include <set>
-#include <mutex>
-#include <condition_variable>
-#include <unordered_map>
+#include "llama.h"
+#include "common.h"
 
 #include "json.hpp"
 
-#include "../llava/clip.h"
+#include <string>
+#include <vector>
+#include <sstream>
+#include <random>
+
+#define DEFAULT_OAICOMPAT_MODEL "gpt-3.5-turbo-0613"
 
 using json = nlohmann::json;
 
@@ -37,83 +38,35 @@ extern bool server_log_json;
 #define LOG_WARNING(MSG, ...) server_log("WARN", __func__, __LINE__, MSG, __VA_ARGS__)
 #define LOG_INFO(   MSG, ...) server_log("INFO", __func__, __LINE__, MSG, __VA_ARGS__)
 
-enum server_state {
-    SERVER_STATE_LOADING_MODEL,  // Server is starting up, model not fully loaded yet
-    SERVER_STATE_READY,          // Server is ready and model is loaded
-    SERVER_STATE_ERROR           // An error occurred, load_model failed
-};
-
-enum task_type {
-    TASK_TYPE_COMPLETION,
-    TASK_TYPE_CANCEL,
-    TASK_TYPE_NEXT_RESPONSE,
-    TASK_TYPE_METRICS
-};
-
-struct task_server {
-    int id = -1; // to be filled by llama_server_queue
-    int target_id;
-    task_type type;
-    json data;
-    bool infill_mode = false;
-    bool embedding_mode = false;
-    int multitask_id = -1;
-};
-
-struct task_result {
-    int id;
-    int multitask_id = -1;
-    bool stop;
-    bool error;
-    json result_json;
-};
-
-struct task_multi {
-    int id;
-    std::set<int> subtasks_remaining{};
-    std::vector<task_result> results{};
-};
-
-// completion token output with probabilities
-struct completion_token_output {
-    struct token_prob
-    {
-        llama_token tok;
-        float prob;
-    };
-
-    std::vector<token_prob> probs;
-    llama_token tok;
-    std::string text_to_send;
-};
-
-struct token_translator {
-    llama_context * ctx;
-    std::string operator()(llama_token tok)                    const { return llama_token_to_piece(ctx, tok); }
-    std::string operator()(const completion_token_output &cto) const { return (*this)(cto.tok); }
-};
+template <typename T>
+static T json_value(const json &body, const std::string &key, const T &default_value) {
+    // Fallback null to default value
+    return body.contains(key) && !body.at(key).is_null()
+        ? body.value(key, default_value)
+        : default_value;
+}
 
 static inline void server_log(const char *level, const char *function, int line, const char *message, const nlohmann::ordered_json &extra) {
     std::stringstream ss_tid;
     ss_tid << std::this_thread::get_id();
     json log = nlohmann::ordered_json{
-        {"tid", ss_tid.str()},
+        {"tid",       ss_tid.str()},
         {"timestamp", time(nullptr)},
     };
 
     if (server_log_json) {
-        log.merge_patch(
-                {
-                        {"level",     level},
-                        {"function",  function},
-                        {"line",      line},
-                        {"msg",       message},
-                });
+        log.merge_patch( {
+            {"level",    level},
+            {"function", function},
+            {"line",     line},
+            {"msg",      message},
+        });
+
         if (!extra.empty()) {
             log.merge_patch(extra);
         }
 
-        std::cout << log.dump(-1, ' ', false, json::error_handler_t::replace) << "\n" << std::flush;
+        printf("%s\n", log.dump(-1, ' ', false, json::error_handler_t::replace).c_str());
     } else {
         char buf[1024];
         snprintf(buf, 1024, "%4s [%24s] %s", level, function, message);
@@ -136,22 +89,13 @@ static inline void server_log(const char *level, const char *function, int line,
 }
 
 //
-// server utils
+// chat template utils
 //
 
-template <typename T>
-static T json_value(const json &body, const std::string &key, const T &default_value) {
-    // Fallback null to default value
-    return body.contains(key) && !body.at(key).is_null()
-        ? body.value(key, default_value)
-        : default_value;
-}
-
 // Check if the template supplied via "--chat-template" is supported or not. Returns true if it's valid
 inline bool verify_custom_template(const std::string & tmpl) {
     llama_chat_message chat[] = {{"user", "test"}};
-    std::vector<char> buf(1);
-    int res = llama_chat_apply_template(nullptr, tmpl.c_str(), chat, 1, true, buf.data(), buf.size());
+    int res = llama_chat_apply_template(nullptr, tmpl.c_str(), chat, 1, true, nullptr, 0);
     return res >= 0;
 }
 
@@ -163,7 +107,7 @@ inline std::string format_chat(const struct llama_model * model, const std::stri
     std::vector<llama_chat_message> chat(messages.size());
 
     for (size_t i = 0; i < messages.size(); ++i) {
-        auto &curr_msg = messages[i];
+        const auto & curr_msg = messages[i];
         str[i*2 + 0]    = json_value(curr_msg, "role",    std::string(""));
         str[i*2 + 1]    = json_value(curr_msg, "content", std::string(""));
         alloc_size     += str[i*2 + 1].length();
@@ -183,262 +127,14 @@ inline std::string format_chat(const struct llama_model * model, const std::stri
         res = llama_chat_apply_template(model, ptr_tmpl, chat.data(), chat.size(), true, buf.data(), buf.size());
     }
 
-    std::string formatted_chat(buf.data(), res);
+    const std::string formatted_chat(buf.data(), res);
+
     LOG_VERBOSE("formatted_chat", {{"text", formatted_chat.c_str()}});
 
     return formatted_chat;
 }
 
 //
-// work queue utils
-//
-
-struct llama_server_queue {
-    int id = 0;
-    std::mutex mutex_tasks;
-    bool running;
-    // queues
-    std::vector<task_server> queue_tasks;
-    std::vector<task_server> queue_tasks_deferred;
-    std::vector<task_multi> queue_multitasks;
-    std::condition_variable condition_tasks;
-    // callback functions
-    std::function<void(task_server&)> callback_new_task;
-    std::function<void(task_multi&)> callback_finish_multitask;
-    std::function<void(void)> callback_run_slots;
-
-    // Add a new task to the end of the queue
-    int post(task_server task) {
-        std::unique_lock<std::mutex> lock(mutex_tasks);
-        if (task.id == -1) {
-            task.id = id++;
-            LOG_VERBOSE("new task id", {{"new_id", task.id}});
-        }
-        queue_tasks.push_back(std::move(task));
-        condition_tasks.notify_one();
-        return task.id;
-    }
-
-    // Add a new task, but defer until one slot is available
-    void defer(task_server task) {
-        std::unique_lock<std::mutex> lock(mutex_tasks);
-        queue_tasks_deferred.push_back(std::move(task));
-    }
-
-    // Get the next id for creating anew task
-    int get_new_id() {
-        std::unique_lock<std::mutex> lock(mutex_tasks);
-        int new_id = id++;
-        LOG_VERBOSE("new task id", {{"new_id", new_id}});
-        return new_id;
-    }
-
-    // Register function to process a new task
-    void on_new_task(std::function<void(task_server&)> callback) {
-        callback_new_task = callback;
-    }
-
-    // Register function to process a multitask when it is finished
-    void on_finish_multitask(std::function<void(task_multi&)> callback) {
-        callback_finish_multitask = callback;
-    }
-
-    // Register the function to be called when all slots data is ready to be processed
-    void on_run_slots(std::function<void(void)> callback) {
-        callback_run_slots = callback;
-    }
-
-    // Call when the state of one slot is changed
-    void notify_slot_changed() {
-        // move deferred tasks back to main loop
-        std::unique_lock<std::mutex> lock(mutex_tasks);
-        for (auto & task : queue_tasks_deferred) {
-            queue_tasks.push_back(std::move(task));
-        }
-        queue_tasks_deferred.clear();
-    }
-
-    // end the start_loop routine
-    void terminate() {
-        {
-            std::unique_lock<std::mutex> lock(mutex_tasks);
-            running = false;
-        }
-        condition_tasks.notify_all();
-    }
-
-    /**
-     * Main loop consists of these steps:
-     * - Wait until a new task arrives
-     * - Process the task (i.e. maybe copy data into slot)
-     * - Check if multitask is finished
-     * - Run all slots
-     */
-    void start_loop() {
-        running = true;
-        while (true) {
-            LOG_VERBOSE("new task may arrive", {});
-            {
-                while (true)
-                {
-                    std::unique_lock<std::mutex> lock(mutex_tasks);
-                    if (queue_tasks.empty()) {
-                        lock.unlock();
-                        break;
-                    }
-                    task_server task = queue_tasks.front();
-                    queue_tasks.erase(queue_tasks.begin());
-                    lock.unlock();
-                    LOG_VERBOSE("callback_new_task", {{"task_id", task.id}});
-                    callback_new_task(task);
-                }
-                LOG_VERBOSE("update_multitasks", {});
-                // check if we have any finished multitasks
-                auto queue_iterator = queue_multitasks.begin();
-                while (queue_iterator != queue_multitasks.end())
-                {
-                    if (queue_iterator->subtasks_remaining.empty())
-                    {
-                        // all subtasks done == multitask is done
-                        task_multi current_multitask = *queue_iterator;
-                        callback_finish_multitask(current_multitask);
-                        // remove this multitask
-                        queue_iterator = queue_multitasks.erase(queue_iterator);
-                    }
-                    else
-                    {
-                        ++queue_iterator;
-                    }
-                }
-                // all tasks in the current loop is processed, slots data is now ready
-                LOG_VERBOSE("callback_run_slots", {});
-                callback_run_slots();
-            }
-            LOG_VERBOSE("wait for new task", {});
-            // wait for new task
-            {
-                std::unique_lock<std::mutex> lock(mutex_tasks);
-                if (queue_tasks.empty()) {
-                    if (!running) {
-                        LOG_VERBOSE("ending start_loop", {});
-                        return;
-                    }
-                    condition_tasks.wait(lock, [&]{
-                        return (!queue_tasks.empty() || !running);
-                    });
-                }
-            }
-        }
-    }
-
-    //
-    // functions to manage multitasks
-    //
-
-    // add a multitask by specifying the id of all subtask (subtask is a task_server)
-    void add_multitask(int multitask_id, std::vector<int>& sub_ids)
-    {
-        std::lock_guard<std::mutex> lock(mutex_tasks);
-        task_multi multi;
-        multi.id = multitask_id;
-        std::copy(sub_ids.begin(), sub_ids.end(), std::inserter(multi.subtasks_remaining, multi.subtasks_remaining.end()));
-        queue_multitasks.push_back(multi);
-    }
-
-    // updatethe remaining subtasks, while appending results to multitask
-    void update_multitask(int multitask_id, int subtask_id, task_result& result)
-    {
-        std::lock_guard<std::mutex> lock(mutex_tasks);
-        for (auto& multitask : queue_multitasks)
-        {
-            if (multitask.id == multitask_id)
-            {
-                multitask.subtasks_remaining.erase(subtask_id);
-                multitask.results.push_back(result);
-            }
-        }
-    }
-};
-
-struct llama_server_response {
-    typedef std::function<void(int, int, task_result&)> callback_multitask_t;
-    callback_multitask_t callback_update_multitask;
-    // for keeping track of all tasks waiting for the result
-    std::set<int> waiting_task_ids;
-    // the main result queue
-    std::vector<task_result> queue_results;
-    std::mutex mutex_results;
-    std::condition_variable condition_results;
-
-    // add the task_id to the list of tasks waiting for response
-    void add_waiting_task_id(int task_id) {
-        LOG_VERBOSE("waiting for task id", {{"task_id", task_id}});
-        std::unique_lock<std::mutex> lock(mutex_results);
-        waiting_task_ids.insert(task_id);
-    }
-
-    // when the request is finished, we can remove task associated with it
-    void remove_waiting_task_id(int task_id) {
-        LOG_VERBOSE("remove waiting for task id", {{"task_id", task_id}});
-        std::unique_lock<std::mutex> lock(mutex_results);
-        waiting_task_ids.erase(task_id);
-    }
-
-    // This function blocks the thread until there is a response for this task_id
-    task_result recv(int task_id) {
-        while (true)
-        {
-            std::unique_lock<std::mutex> lock(mutex_results);
-            condition_results.wait(lock, [&]{
-                return !queue_results.empty();
-            });
-
-            for (int i = 0; i < (int) queue_results.size(); i++)
-            {
-                if (queue_results[i].id == task_id)
-                {
-                    assert(queue_results[i].multitask_id == -1);
-                    task_result res = queue_results[i];
-                    queue_results.erase(queue_results.begin() + i);
-                    return res;
-                }
-            }
-        }
-
-        // should never reach here
-    }
-
-    // Register the function to update multitask
-    void on_multitask_update(callback_multitask_t callback) {
-        callback_update_multitask = callback;
-    }
-
-    // Send a new result to a waiting task_id
-    void send(task_result result) {
-        std::unique_lock<std::mutex> lock(mutex_results);
-        LOG_VERBOSE("send new result", {{"task_id", result.id}});
-        for (auto& task_id : waiting_task_ids) {
-            // LOG_TEE("waiting task id %i \n", task_id);
-            // for now, tasks that have associated parent multitasks just get erased once multitask picks up the result
-            if (result.multitask_id == task_id)
-            {
-                LOG_VERBOSE("callback_update_multitask", {{"task_id", task_id}});
-                callback_update_multitask(task_id, result.id, result);
-                continue;
-            }
-
-            if (result.id == task_id)
-            {
-                LOG_VERBOSE("queue_results.push_back", {{"task_id", task_id}});
-                queue_results.push_back(result);
-                condition_results.notify_all();
-                return;
-            }
-        }
-    }
-};
-
-//
 // base64 utils (TODO: move to common in the future)
 //
 
@@ -447,13 +143,11 @@ static const std::string base64_chars =
              "abcdefghijklmnopqrstuvwxyz"
              "0123456789+/";
 
-static inline bool is_base64(uint8_t c)
-{
+static inline bool is_base64(uint8_t c) {
     return (isalnum(c) || (c == '+') || (c == '/'));
 }
 
-static inline std::vector<uint8_t> base64_decode(const std::string & encoded_string)
-{
+static inline std::vector<uint8_t> base64_decode(const std::string & encoded_string) {
     int i = 0;
     int j = 0;
     int in_ = 0;
@@ -465,13 +159,10 @@ static inline std::vector<uint8_t> base64_decode(const std::string & encoded_str
 
     std::vector<uint8_t> ret;
 
-    while (in_len-- && (encoded_string[in_] != '=') && is_base64(encoded_string[in_]))
-    {
+    while (in_len-- && (encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
         char_array_4[i++] = encoded_string[in_]; in_++;
-        if (i == 4)
-        {
-            for (i = 0; i <4; i++)
-            {
+        if (i == 4) {
+            for (i = 0; i < 4; i++) {
                 char_array_4[i] = base64_chars.find(char_array_4[i]);
             }
 
@@ -479,23 +170,20 @@ static inline std::vector<uint8_t> base64_decode(const std::string & encoded_str
             char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
             char_array_3[2] = ((char_array_4[2] & 0x3) << 6) +   char_array_4[3];
 
-            for (i = 0; (i < 3); i++)
-            {
+            for (i = 0; (i < 3); i++) {
                 ret.push_back(char_array_3[i]);
             }
+
             i = 0;
         }
     }
 
-    if (i)
-    {
-        for (j = i; j <4; j++)
-        {
+    if (i) {
+        for (j = i; j < 4; j++) {
             char_array_4[j] = 0;
         }
 
-        for (j = 0; j <4; j++)
-        {
+        for (j = 0; j < 4; j++) {
             char_array_4[j] = base64_chars.find(char_array_4[j]);
         }
 
@@ -503,8 +191,7 @@ static inline std::vector<uint8_t> base64_decode(const std::string & encoded_str
         char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
         char_array_3[2] = ((char_array_4[2] & 0x3) << 6) +   char_array_4[3];
 
-        for (j = 0; (j < i - 1); j++)
-        {
+        for (j = 0; j < i - 1; j++) {
             ret.push_back(char_array_3[j]);
         }
     }
@@ -516,8 +203,7 @@ static inline std::vector<uint8_t> base64_decode(const std::string & encoded_str
 // random string / id
 //
 
-static std::string random_string()
-{
+static std::string random_string() {
     static const std::string str("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz");
 
     std::random_device rd;
@@ -532,10 +218,10 @@ static std::string random_string()
     return result;
 }
 
-static std::string gen_chatcmplid()
-{
+static std::string gen_chatcmplid() {
     std::stringstream chatcmplid;
     chatcmplid << "chatcmpl-" << random_string();
+
     return chatcmplid.str();
 }
 
@@ -543,91 +229,316 @@ static std::string gen_chatcmplid()
 // other common utils
 //
 
-static size_t common_part(const std::vector<llama_token> &a, const std::vector<llama_token> &b)
-{
+static size_t common_part(const std::vector<llama_token> & a, const std::vector<llama_token> & b) {
     size_t i;
-    for (i = 0; i < a.size() && i < b.size() && a[i] == b[i]; i++)
-    {
-    }
+    for (i = 0; i < a.size() && i < b.size() && a[i] == b[i]; i++) {}
+
     return i;
 }
 
-static bool ends_with(const std::string &str, const std::string &suffix)
-{
-    return str.size() >= suffix.size() &&
-           0 == str.compare(str.size() - suffix.size(), suffix.size(), suffix);
+static bool ends_with(const std::string & str, const std::string & suffix) {
+    return str.size() >= suffix.size() && 0 == str.compare(str.size() - suffix.size(), suffix.size(), suffix);
 }
 
-static size_t find_partial_stop_string(const std::string &stop,
-                                       const std::string &text)
-{
-    if (!text.empty() && !stop.empty())
-    {
+static size_t find_partial_stop_string(const std::string &stop, const std::string &text) {
+    if (!text.empty() && !stop.empty()) {
         const char text_last_char = text.back();
-        for (int64_t char_index = stop.size() - 1; char_index >= 0; char_index--)
-        {
-            if (stop[char_index] == text_last_char)
-            {
+        for (int64_t char_index = stop.size() - 1; char_index >= 0; char_index--) {
+            if (stop[char_index] == text_last_char) {
                 const std::string current_partial = stop.substr(0, char_index + 1);
-                if (ends_with(text, current_partial))
-                {
+                if (ends_with(text, current_partial)) {
                     return text.size() - char_index - 1;
                 }
             }
         }
     }
+
     return std::string::npos;
 }
 
 // TODO: reuse llama_detokenize
 template <class Iter>
-static std::string tokens_to_str(llama_context *ctx, Iter begin, Iter end)
-{
+static std::string tokens_to_str(llama_context * ctx, Iter begin, Iter end) {
     std::string ret;
-    for (; begin != end; ++begin)
-    {
+    for (; begin != end; ++begin) {
         ret += llama_token_to_piece(ctx, *begin);
     }
+
     return ret;
 }
 
 // format incomplete utf-8 multibyte character for output
-static std::string tokens_to_output_formatted_string(const llama_context *ctx, const llama_token token)
-{
+static std::string tokens_to_output_formatted_string(const llama_context * ctx, const llama_token token) {
     std::string out = token == -1 ? "" : llama_token_to_piece(ctx, token);
+
     // if the size is 1 and first bit is 1, meaning it's a partial character
     //   (size > 1 meaning it's already a known token)
-    if (out.size() == 1 && (out[0] & 0x80) == 0x80)
-    {
+    if (out.size() == 1 && (out[0] & 0x80) == 0x80) {
         std::stringstream ss;
         ss << std::hex << (out[0] & 0xff);
         std::string res(ss.str());
         out = "byte: \\x" + res;
     }
+
     return out;
 }
 
+struct completion_token_output {
+    llama_token tok;
+    std::string text_to_send;
+
+    struct token_prob {
+        llama_token tok;
+        float prob;
+    };
+
+    std::vector<token_prob> probs;
+};
+
 // convert a vector of completion_token_output to json
-static json probs_vector_to_json(const llama_context *ctx, const std::vector<completion_token_output> &probs)
-{
+static json probs_vector_to_json(const llama_context * ctx, const std::vector<completion_token_output> & probs) {
     json out = json::array();
-    for (const auto &prob : probs)
-    {
+
+    for (const auto & prob : probs) {
         json probs_for_token = json::array();
-        for (const auto &p : prob.probs)
-        {
-            std::string tok_str = tokens_to_output_formatted_string(ctx, p.tok);
-            probs_for_token.push_back(json
-            {
+
+        for (const auto & p : prob.probs) {
+            const std::string tok_str = tokens_to_output_formatted_string(ctx, p.tok);
+            probs_for_token.push_back(json {
                 {"tok_str", tok_str},
                 {"prob",    p.prob},
             });
         }
-        std::string tok_str = tokens_to_output_formatted_string(ctx, prob.tok);
-        out.push_back(json{
+
+        const std::string tok_str = tokens_to_output_formatted_string(ctx, prob.tok);
+        out.push_back(json {
             {"content", tok_str},
             {"probs",   probs_for_token},
         });
     }
+
     return out;
 }
+
+//
+// OAI utils
+//
+
+static json oaicompat_completion_params_parse(
+    const struct llama_model * model,
+    const json & body, /* openai api json semantics */
+    const std::string & chat_template) {
+    json llama_params;
+
+    llama_params["__oaicompat"] = true;
+
+    // Map OpenAI parameters to llama.cpp parameters
+    //
+    // For parameters that are defined by the OpenAI documentation (e.g.
+    // temperature), we explicitly specify OpenAI's intended default; we
+    // need to do that because sometimes OpenAI disagrees with llama.cpp
+    //
+    // https://platform.openai.com/docs/api-reference/chat/create
+    llama_sampling_params default_sparams;
+    llama_params["model"]             = json_value(body,   "model",             std::string("unknown"));
+    llama_params["prompt"]            = format_chat(model, chat_template,       body["messages"]);
+    llama_params["cache_prompt"]      = json_value(body,   "cache_prompt",      false);
+    llama_params["temperature"]       = json_value(body,   "temperature",       0.0);
+    llama_params["top_k"]             = json_value(body,   "top_k",             default_sparams.top_k);
+    llama_params["top_p"]             = json_value(body,   "top_p",             1.0);
+    llama_params["n_predict"]         = json_value(body,   "max_tokens",        -1);
+    llama_params["logit_bias"]        = json_value(body,   "logit_bias",        json::object());
+    llama_params["frequency_penalty"] = json_value(body,   "frequency_penalty", 0.0);
+    llama_params["presence_penalty"]  = json_value(body,   "presence_penalty",  0.0);
+    llama_params["seed"]              = json_value(body,   "seed",              LLAMA_DEFAULT_SEED);
+    llama_params["stream"]            = json_value(body,   "stream",            false);
+    llama_params["mirostat"]          = json_value(body,   "mirostat",          default_sparams.mirostat);
+    llama_params["mirostat_tau"]      = json_value(body,   "mirostat_tau",      default_sparams.mirostat_tau);
+    llama_params["mirostat_eta"]      = json_value(body,   "mirostat_eta",      default_sparams.mirostat_eta);
+    llama_params["penalize_nl"]       = json_value(body,   "penalize_nl",       default_sparams.penalize_nl);
+    llama_params["typical_p"]         = json_value(body,   "typical_p",         default_sparams.typical_p);
+    llama_params["repeat_last_n"]     = json_value(body,   "repeat_last_n",     default_sparams.penalty_last_n);
+    llama_params["ignore_eos"]        = json_value(body,   "ignore_eos",        false);
+    llama_params["tfs_z"]             = json_value(body,   "tfs_z",             default_sparams.tfs_z);
+
+    if (body.count("grammar") != 0) {
+        llama_params["grammar"] = json_value(body, "grammar", json::object());
+    }
+
+    // Handle 'stop' field
+    if (body.contains("stop") && body["stop"].is_string()) {
+        llama_params["stop"] = json::array({body["stop"].get<std::string>()});
+    } else {
+        llama_params["stop"] = json_value(body, "stop", json::array());
+    }
+
+    // Ensure there is ChatML-specific end sequence among stop words
+    llama_params["stop"].push_back("<|im_end|>");
+
+    return llama_params;
+}
+
+static json format_final_response_oaicompat(const json & request, json result, bool streaming = false) {
+    bool stopped_word        = result.count("stopped_word") != 0;
+    bool stopped_eos         = json_value(result, "stopped_eos", false);
+    int num_tokens_predicted = json_value(result, "tokens_predicted", 0);
+    int num_prompt_tokens    = json_value(result, "tokens_evaluated", 0);
+    std::string content      = json_value(result, "content", std::string(""));
+
+    std::string finish_reason = "length";
+    if (stopped_word || stopped_eos) {
+        finish_reason = "stop";
+    }
+
+    json choices =
+        streaming ? json::array({json{{"finish_reason", finish_reason},
+                                        {"index", 0},
+                                        {"delta", json::object()}}})
+                  : json::array({json{{"finish_reason", finish_reason},
+                                        {"index", 0},
+                                        {"message", json{{"content", content},
+                                                         {"role", "assistant"}}}}});
+
+    std::time_t t = std::time(0);
+
+    json res = json {
+        {"choices", choices},
+        {"created", t},
+        {"model",
+            json_value(request, "model", std::string(DEFAULT_OAICOMPAT_MODEL))},
+        {"object", streaming ? "chat.completion.chunk" : "chat.completion"},
+        {"usage", json {
+            {"completion_tokens", num_tokens_predicted},
+            {"prompt_tokens",     num_prompt_tokens},
+            {"total_tokens",      num_tokens_predicted + num_prompt_tokens}
+        }},
+        {"id", gen_chatcmplid()}
+    };
+
+    if (server_verbose) {
+        res["__verbose"] = result;
+    }
+
+    if (result.contains("completion_probabilities")) {
+        res["completion_probabilities"] = json_value(result, "completion_probabilities", json::array());
+    }
+
+    return res;
+}
+
+// return value is vector as there is one case where we might need to generate two responses
+static std::vector<json> format_partial_response_oaicompat(json result) {
+    if (!result.contains("model") || !result.contains("oaicompat_token_ctr")) {
+        return std::vector<json>({result});
+    }
+
+    bool first = json_value(result, "oaicompat_token_ctr", 0) == 0;
+    std::string modelname = json_value(result, "model", std::string(DEFAULT_OAICOMPAT_MODEL));
+
+    bool stopped_word   = json_value(result, "stopped_word",  false);
+    bool stopped_eos    = json_value(result, "stopped_eos",   false);
+    bool stopped_limit  = json_value(result, "stopped_limit", false);
+    std::string content = json_value(result, "content",       std::string(""));
+
+    std::string finish_reason;
+    if (stopped_word || stopped_eos) {
+        finish_reason = "stop";
+    }
+    if (stopped_limit) {
+        finish_reason = "length";
+    }
+
+    std::time_t t = std::time(0);
+
+    json choices;
+
+    if (!finish_reason.empty()) {
+        choices = json::array({json{{"finish_reason", finish_reason},
+                                    {"index", 0},
+                                    {"delta", json::object()}}});
+    } else {
+        if (first) {
+            if (content.empty()) {
+                choices = json::array({json{{"finish_reason", nullptr},
+                                            {"index", 0},
+                                            {"delta", json{{"role", "assistant"}}}}});
+            } else {
+                // We have to send this as two updates to conform to openai behavior
+                json initial_ret = json{{"choices", json::array({json{
+                                        {"finish_reason", nullptr},
+                                        {"index", 0},
+                                        {"delta", json{
+                                            {"role", "assistant"}
+                                        }}}})},
+                            {"created", t},
+                            {"id", gen_chatcmplid()},
+                            {"model", modelname},
+                            {"object", "chat.completion.chunk"}};
+
+                json second_ret = json{
+                            {"choices", json::array({json{{"finish_reason", nullptr},
+                                                            {"index", 0},
+                                                            {"delta", json{
+                                                            {"content", content}}}
+                                                            }})},
+                            {"created", t},
+                            {"id", gen_chatcmplid()},
+                            {"model", modelname},
+                            {"object", "chat.completion.chunk"}};
+
+                return std::vector<json>({initial_ret, second_ret});
+            }
+        } else {
+            // Some idiosyncrasy in task processing logic makes several trailing calls
+            // with empty content, we ignore these at the calee site.
+            if (content.empty()) {
+                return std::vector<json>({json::object()});
+            }
+
+            choices = json::array({json{
+                {"finish_reason", nullptr},
+                {"index", 0},
+                {"delta",
+                json{
+                    {"content", content},
+                }},
+            }});
+        }
+    }
+
+    json ret = json {
+        {"choices", choices},
+        {"created", t},
+        {"id",      gen_chatcmplid()},
+        {"model",   modelname},
+        {"object",  "chat.completion.chunk"}
+    };
+
+    return std::vector<json>({ret});
+}
+
+static json format_embeddings_response_oaicompat(const json & request, const json & embeddings) {
+    json res = json {
+        {"model", json_value(request, "model", std::string(DEFAULT_OAICOMPAT_MODEL))},
+        {"object", "list"},
+        {"usage", json {
+            {"prompt_tokens", 0},
+            {"total_tokens", 0}
+        }},
+        {"data", embeddings}
+    };
+
+    return res;
+}
+
+static json format_tokenizer_response(const std::vector<llama_token> & tokens) {
+    return json {
+        {"tokens", tokens}
+    };
+}
+
+static json format_detokenized_response(const std::string & content) {
+    return json {
+        {"content", content}
+    };
+}