fix(model-loading): keep track of open GRPC Clients (#3377)

Due to a previous refactor we moved the client constructor tight to the
model address, however that was just a string which we would use to
build the client each time.

With this change we make the loader to return a *Model which carries a
constructor for the client and stores the client on the first
connection.

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

pkg/model/template.go

@@ -0,0 +1,52 @@
+package model
+
+import (
+	"fmt"
+
+	"github.com/mudler/LocalAI/pkg/functions"
+	"github.com/mudler/LocalAI/pkg/templates"
+)
+
+// Rather than pass an interface{} to the prompt template:
+// These are the definitions of all possible variables LocalAI will currently populate for use in a prompt template file
+// Please note: Not all of these are populated on every endpoint - your template should either be tested for each endpoint you map it to, or tolerant of zero values.
+type PromptTemplateData struct {
+	SystemPrompt         string
+	SuppressSystemPrompt bool // used by chat specifically to indicate that SystemPrompt above should be _ignored_
+	Input                string
+	Instruction          string
+	Functions            []functions.Function
+	MessageIndex         int
+}
+
+type ChatMessageTemplateData struct {
+	SystemPrompt string
+	Role         string
+	RoleName     string
+	FunctionName string
+	Content      string
+	MessageIndex int
+	Function     bool
+	FunctionCall interface{}
+	LastMessage  bool
+}
+
+const (
+	ChatPromptTemplate templates.TemplateType = iota
+	ChatMessageTemplate
+	CompletionPromptTemplate
+	EditPromptTemplate
+	FunctionsPromptTemplate
+)
+
+func (ml *ModelLoader) EvaluateTemplateForPrompt(templateType templates.TemplateType, templateName string, in PromptTemplateData) (string, error) {
+	// TODO: should this check be improved?
+	if templateType == ChatMessageTemplate {
+		return "", fmt.Errorf("invalid templateType: ChatMessage")
+	}
+	return ml.templates.EvaluateTemplate(templateType, templateName, in)
+}
+
+func (ml *ModelLoader) EvaluateTemplateForChatMessage(templateName string, messageData ChatMessageTemplateData) (string, error) {
+	return ml.templates.EvaluateTemplate(ChatMessageTemplate, templateName, messageData)
+}