feat: conversion for gnmi fileds (#1079)

inputs/gnmi/gnmi.go

@@ -94,7 +94,8 @@ type Subscription struct {
 	// Mark this subscription as a tag-only lookup source, not emitting any metric
 	TagOnly bool `toml:"tag_only" deprecated:"1.25.0;2.0.0;please use 'tag_subscription's instead"`
 
-	DisableConcatenation bool `toml:"disable_concatenation"`
+	DisableConcatenation bool   `toml:"disable_concatenation"`
+	Conversion           string `toml:"conversion"`
 }
 
 // Tag Subscription for a gNMI client

inputs/gnmi/handler.go

@@ -261,19 +261,38 @@ func (h *handler) handleSubscribeResponseUpdate(slist *types.SampleList, respons
 		if strings.HasPrefix(name, inputName) {
 			prefix = ""
 		}
+		value := field.value
 		disableConcatenating := false
 		for _, sub := range h.subs {
-			if strings.HasSuffix(field.path.String(), sub.Path) {
+			base, _ := field.path.split()
+			if strings.HasSuffix(base, sub.Path) {
 				// field.path => origin:path
 				// sub.path => path
 				disableConcatenating = sub.DisableConcatenation
+				switch sub.Conversion {
+				case "ieeefloat32":
+					switch val := field.value.(type) {
+					case string:
+						v, err := string2float32(val)
+						if err != nil {
+						}
+
+						value = v
+					case []uint8:
+						v, err := bytes2float32(val)
+						if err != nil {
+
+						}
+						value = v
+					}
+				}
 			}
 		}
 		if !disableConcatenating {
 			name = name + "_" + key
 		}
 
-		sample := types.NewSample(prefix, name, field.value, tags).SetTime(timestamp)
+		sample := types.NewSample(prefix, name, value, tags).SetTime(timestamp)
 		slist.PushFront(sample)
 	}
 

inputs/gnmi/ieeefloat32.go

@@ -0,0 +1,39 @@
+package gnmi
+
+import (
+	"encoding/base64"
+	"encoding/binary"
+	"fmt"
+	"math"
+)
+
+func string2float32(base64Str string) (float32, error) {
+	// 解码Base64字符串
+	decodedBytes, err := base64.StdEncoding.DecodeString(base64Str)
+	if err != nil {
+		return 0.0, fmt.Errorf("base64 string %s decode error: %v", base64Str, err)
+	}
+
+	// 确保解码后的字节切片长度为4（32位）
+	if len(decodedBytes) != 4 {
+		return 0.0, fmt.Errorf("length after decoding is not 4 bytes, data type is not float32")
+	}
+
+	// 将字节切片转换为uint32
+	bits := binary.BigEndian.Uint32(decodedBytes)
+
+	// 将uint32转换为float32
+	return math.Float32frombits(bits), nil
+}
+
+func bytes2float32(bytes []uint8) (float32, error) {
+	if len(bytes) != 4 {
+		return 0.0, fmt.Errorf("length after decoding is not 4 bytes, data type is not float32")
+	}
+
+	// 将字节切片转换为uint32
+	bits := binary.BigEndian.Uint32(bytes)
+
+	// 将uint32转换为float32
+	return math.Float32frombits(bits), nil
+}