rest: bypass jq when it's convenient

Adding a custom parser for GPT-2 queries because it's easier this way.

plugins/rest/rest.go

@@ -28,6 +28,24 @@ type RestPlugin struct {
 	handlers bot.HandlerTable
 }
 
+type postProcessor func(interface{}) string
+
+var postProcessors = map[string]postProcessor{
+	"gpt2": func(input interface{}) string {
+		values := input.(map[string]interface{})
+		text := values["text"].(string)
+		lastStop := strings.LastIndexAny(text, ".!?")
+		if lastStop > 0 {
+			text = text[:lastStop+1]
+		}
+		eot := strings.LastIndex(text, "<|endoftext|>")
+		if eot > 0 {
+			text = text[:eot]
+		}
+		return text
+	},
+}
+
 func New(b bot.Bot) *RestPlugin {
 	p := &RestPlugin{
 		b:        b,
@@ -298,25 +316,29 @@ func (p *RestPlugin) mkHandler(w wire) bot.ResponseHandler {
 		var returnValues interface{}
 		json.Unmarshal(body, &returnValues)
 
-		query, err := gojq.Parse(w.ReturnField)
-		if err != nil {
-			msg := fmt.Sprintf("Wire handler did not find return value: %s => `%s`", w.URL, w.ReturnField)
-			p.b.Send(r.Conn, bot.Message, r.Msg.Channel, msg)
-			return true
-		}
-
 		var msg string
-		iter := query.Run(returnValues) // or query.RunWithContext
+		if pp, ok := postProcessors[w.ReturnField]; ok {
+			msg = pp(returnValues)
+		} else {
+			query, err := gojq.Parse(w.ReturnField)
+			if err != nil {
+				msg := fmt.Sprintf("Wire handler did not find return value: %s => `%s`", w.URL, w.ReturnField)
+				p.b.Send(r.Conn, bot.Message, r.Msg.Channel, msg)
+				return true
+			}
 
-		for {
+			iter := query.Run(returnValues) // or query.RunWithContext
-			v, ok := iter.Next()
+
-			if !ok {
+			for {
-				break
+				v, ok := iter.Next()
+				if !ok {
+					break
+				}
+				if err, ok := v.(error); ok {
+					return p.handleErr(err, r)
+				}
+				msg += fmt.Sprintf("%s\n", v)
 			}
-			if err, ok := v.(error); ok {
-				return p.handleErr(err, r)
-			}
-			msg += fmt.Sprintf("%s\n", v)
 		}
 
 		msg = strings.TrimSpace(msg)
@@ -327,7 +349,7 @@ func (p *RestPlugin) mkHandler(w wire) bot.ResponseHandler {
 
 func (p *RestPlugin) handleErr(err error, r bot.Request) bool {
 	if err != nil {
-		p.b.Send(r.Conn, bot.Message, r.Msg.Channel, "Error: %s", err)
+		p.b.Send(r.Conn, bot.Message, r.Msg.Channel, fmt.Sprintf("Error: %s", err))
 		return true
 	}
 	return false