Mtr exporter

package main

import (
    "encoding/json"
    "log"
    "net/http"
    "os/exec"

    "github.com/gorilla/mux"
)

type MTRResult struct {
    // Define the structure to match MTR JSON output
}

func runMTR(target string) (string, error) {
    cmd := exec.Command("mtr", "--report", "--json", target)
    out, err := cmd.Output()
    if err != nil {
        return "", err
    }
    return string(out), nil
}

func probeHandler(w http.ResponseWriter, r *http.Request) {
    target := r.URL.Query().Get("target")
    if target == "" {
        target = "8.8.8.8"
    }

    result, err := runMTR(target)
    if err != nil {
        http.Error(w, err.Error(), http.StatusInternalServerError)
        return
    }

    w.Header().Set("Content-Type", "application/json")
    w.Write([]byte(result))
}

func main() {
    r := mux.NewRouter()
    r.HandleFunc("/probe", probeHandler).Methods("GET")
    http.Handle("/", r)
    log.Println("Starting server on :9115")
    log.Fatal(http.ListenAndServe(":9115", nil))
}

Dockerfile

# Start from the official Go image
FROM golang:1.18 as builder

# Set the Current Working Directory inside the container
WORKDIR /app

# Copy go.mod and go.sum files
COPY go.mod go.sum ./

# Download all dependencies. Dependencies will be cached if the go.mod and go.sum files are not changed
RUN go mod download

# Copy the source from the current directory to the Working Directory inside the container
COPY . .

# Build the Go app
RUN go build -o mtr_probe .

# Use a minimal image to run the application
FROM debian:bullseye-slim

# Install MTR
RUN apt-get update && apt-get install -y mtr-tiny

# Copy the pre-built binary file from the previous stage
COPY --from=builder /app/mtr_probe /usr/local/bin/mtr_probe

# Expose port 9115 to the outside world
EXPOSE 9115

# Command to run the executable
CMD ["mtr_probe"]

go.mod

module mtr_probe

go 1.18

require github.com/gorilla/mux v1.8.0

sh

# Build the Docker image
docker build -t mtr-probe .

# Run the Docker container
docker run -d -p 9115:9115 mtr-probe

scrape_configs:
  - job_name: 'blackbox'
    metrics_path: /probe
    params:
      module: [mtr]  # Look for an 'mtr' module in blackbox exporter config.
    static_configs:
      - targets:
        - 'example.com'
    relabel_configs:
      - source_labels: [__address__]
        target_label: __param_target
      - source_labels: [__param_target]
        target_label: instance
      - target_label: __address__
        replacement: 127.0.0.1:9115  # MTR prober address