read runner parameter options from map

- read runner options from map to see what was specified explicitly and overwrite zero values

api/types.go

@@ -3,9 +3,12 @@ package api
 import (
 	"encoding/json"
 	"fmt"
+	"log"
 	"math"
 	"os"
+	"reflect"
 	"runtime"
+	"strings"
 	"time"
 )
 
@@ -34,7 +37,7 @@ type GenerateRequest struct {
 	Prompt  string `json:"prompt"`
 	Context []int  `json:"context,omitempty"`
 
-	Options `json:"options"`
+	Options map[string]interface{} `json:"options"`
 }
 
 type CreateRequest struct {
@@ -177,6 +180,81 @@ type Options struct {
 	NumThread int `json:"num_thread,omitempty"`
 }
 
+func (opts *Options) FromMap(m map[string]interface{}) error {
+	valueOpts := reflect.ValueOf(opts).Elem() // names of the fields in the options struct
+	typeOpts := reflect.TypeOf(opts).Elem()   // types of the fields in the options struct
+
+	// build map of json struct tags to their types
+	jsonOpts := make(map[string]reflect.StructField)
+	for _, field := range reflect.VisibleFields(typeOpts) {
+		jsonTag := strings.Split(field.Tag.Get("json"), ",")[0]
+		if jsonTag != "" {
+			jsonOpts[jsonTag] = field
+		}
+	}
+
+	for key, val := range m {
+		if opt, ok := jsonOpts[key]; ok {
+			field := valueOpts.FieldByName(opt.Name)
+			if field.IsValid() && field.CanSet() {
+				switch field.Kind() {
+				case reflect.Int:
+					// when JSON unmarshals numbers, it uses float64 by default, not int
+					val, ok := val.(float64)
+					if !ok {
+						log.Printf("could not convert model parmeter %v to int, skipped", key)
+						continue
+					}
+					field.SetInt(int64(val))
+				case reflect.Bool:
+					val, ok := val.(bool)
+					if !ok {
+						log.Printf("could not convert model parmeter %v to bool, skipped", key)
+						continue
+					}
+					field.SetBool(val)
+				case reflect.Float32:
+					// JSON unmarshals to float64
+					val, ok := val.(float64)
+					if !ok {
+						log.Printf("could not convert model parmeter %v to float32, skipped", key)
+						continue
+					}
+					field.SetFloat(val)
+				case reflect.String:
+					val, ok := val.(string)
+					if !ok {
+						log.Printf("could not convert model parmeter %v to string, skipped", key)
+						continue
+					}
+					field.SetString(val)
+				case reflect.Slice:
+					// JSON unmarshals to []interface{}, not []string
+					val, ok := val.([]interface{})
+					if !ok {
+						log.Printf("could not convert model parmeter %v to slice, skipped", key)
+						continue
+					}
+					// convert []interface{} to []string
+					slice := make([]string, len(val))
+					for i, item := range val {
+						str, ok := item.(string)
+						if !ok {
+							log.Printf("could not convert model parmeter %v to slice of strings, skipped", key)
+							continue
+						}
+						slice[i] = str
+					}
+					field.Set(reflect.ValueOf(slice))
+				default:
+					return fmt.Errorf("unknown type loading config params: %v", field.Kind())
+				}
+			}
+		}
+	}
+	return nil
+}
+
 func DefaultOptions() Options {
 	return Options{
 		Seed: -1,