path: root/cmd/puppeth/module_ethstats.go

// Copyright 2017 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

package main

import (
    "bytes"
    "fmt"
    "math/rand"
    "path/filepath"
    "strings"
    "text/template"

    "github.com/ethereum/go-ethereum/log"
)

// ethstatsDockerfile is the Dockerfile required to build an ethstats backend
// and associated monitoring site.
var ethstatsDockerfile = `
FROM mhart/alpine-node:latest

RUN \
  apk add --update git                                         && \
  git clone --depth=1 https://github.com/karalabe/eth-netstats && \
    apk del git && rm -rf /var/cache/apk/*                       && \
    \
  cd /eth-netstats && npm install && npm install -g grunt-cli && grunt

WORKDIR /eth-netstats
EXPOSE 3000

RUN echo 'module.exports = {trusted: [{{.Trusted}}], banned: []};' > lib/utils/config.js

CMD ["npm", "start"]
`

// ethstatsComposefile is the docker-compose.yml file required to deploy and
// maintain an ethstats monitoring site.
var ethstatsComposefile = `
version: '2'
services:
  ethstats:
    build: .
    image: {{.Network}}/ethstats{{if not .VHost}}
    ports:
      - "{{.Port}}:3000"{{end}}
    environment:
      - WS_SECRET={{.Secret}}{{if .VHost}}
      - VIRTUAL_HOST={{.VHost}}{{end}}
    restart: always
`

// deployEthstats deploys a new ethstats container to a remote machine via SSH,
// docker and docker-compose. If an instance with the specified network name
// already exists there, it will be overwritten!
func deployEthstats(client *sshClient, network string, port int, secret string, vhost string, trusted []string) ([]byte, error) {
    // Generate the content to upload to the server
    workdir := fmt.Sprintf("%d", rand.Int63())
    files := make(map[string][]byte)

    for i, address := range trusted {
        trusted[i] = fmt.Sprintf("\"%s\"", address)
    }

    dockerfile := new(bytes.Buffer)
    template.Must(template.New("").Parse(ethstatsDockerfile)).Execute(dockerfile, map[string]interface{}{
        "Trusted": strings.Join(trusted, ", "),
    })
    files[filepath.Join(workdir, "Dockerfile")] = dockerfile.Bytes()

    composefile := new(bytes.Buffer)
    template.Must(template.New("").Parse(ethstatsComposefile)).Execute(composefile, map[string]interface{}{
        "Network": network,
        "Port":    port,
        "Secret":  secret,
        "VHost":   vhost,
    })
    files[filepath.Join(workdir, "docker-compose.yaml")] = composefile.Bytes()

    // Upload the deployment files to the remote server (and clean up afterwards)
    if out, err := client.Upload(files); err != nil {
        return out, err
    }
    defer client.Run("rm -rf " + workdir)

    // Build and deploy the ethstats service
    return nil, client.Stream(fmt.Sprintf("cd %s && docker-compose -p %s up -d --build", workdir, network))
}

// ethstatsInfos is returned from an ethstats status check to allow reporting
// various configuration parameters.
type ethstatsInfos struct {
    host   string
    port   int
    secret string
    config string
}

// String implements the stringer interface.
func (info *ethstatsInfos) String() string {
    return fmt.Sprintf("host=%s, port=%d, secret=%s", info.host, info.port, info.secret)
}

// checkEthstats does a health-check against an ethstats server to verify whether
// it's running, and if yes, gathering a collection of useful infos about it.
func checkEthstats(client *sshClient, network string) (*ethstatsInfos, error) {
    // Inspect a possible ethstats container on the host
    infos, err := inspectContainer(client, fmt.Sprintf("%s_ethstats_1", network))
    if err != nil {
        return nil, err
    }
    if !infos.running {
        return nil, ErrServiceOffline
    }
    // Resolve the port from the host, or the reverse proxy
    port := infos.portmap["3000/tcp"]
    if port == 0 {
        if proxy, _ := checkNginx(client, network); proxy != nil {
            port = proxy.port
        }
    }
    if port == 0 {
        return nil, ErrNotExposed
    }
    // Resolve the host from the reverse-proxy and configure the connection string
    host := infos.envvars["VIRTUAL_HOST"]
    if host == "" {
        host = client.server
    }
    secret := infos.envvars["WS_SECRET"]
    config := fmt.Sprintf("%s@%s", secret, host)
    if port != 80 && port != 443 {
        config += fmt.Sprintf(":%d", port)
    }
    // Run a sanity check to see if the port is reachable
    if err = checkPort(host, port); err != nil {
        log.Warn("Ethstats service seems unreachable", "server", host, "port", port, "err", err)
    }
    // Container available, assemble and return the useful infos
    return &ethstatsInfos{
        host:   host,
        port:   port,
        secret: secret,
        config: config,
    }, nil
}