jdel/go-syno

package syno // import jdel.org/go-syno/syno

import (
    "net/http"
    "os"
    "regexp"
    "strings"

    "github.com/PuerkitoBio/goquery"
    "github.com/robertkrimen/otto"
    log "github.com/sirupsen/logrus"
    yaml "gopkg.in/yaml.v2"
)

// Model represents a Synology model
type Model struct {
    Name    string `json:"name,omitempty"`
    CPU     string `json:"cpu,omitempty"`
    Cores   string `json:"cores,omitempty"`
    Threads string `json:"threads,omitempty"`
    FPU     string `json:"fpu,omitempty"`
    Arch    string `json:"arch,omitempty"`
    RAM     string `json:"ram,omitempty"`
}

// Models is a slice of Model
type Models []*Model

// Families contains families - arch mappings
var Families map[string][]string

func init() {
    // https://github.com/SynologyOpenSource/pkgscripts-ng/blob/master/include/pkg_util.sh#L107
    Families = make(map[string][]string)
    Families["x86_64"] = []string{"x86", "bromolow", "cedarview", "avoton", "braswell", "broadwell", "dockerx64", "kvmx64", "grantley", "denverton", "apollolake"}
    Families["i686"] = []string{"evansport"}
    Families["armv5"] = []string{"88f6281", "88f6282", "88f5281"}
    Families["armv7"] = []string{"alpine", "alpine4k", "ipq806x", "northstarplus"}
    Families["armv8"] = []string{"rtd1296"}
    Families["ppc"] = []string{"ppc854x", "ppc853x", "ppc824x", "powerpc", "qoriq"}
}

// GetModels returns Synology models from file or fall back to web craling
func GetModels(forceRefresh bool) (Models, error) {
    if modelsFileExists() && !forceRefresh {
        log.Debugf("Reading models from file %s", o.ModelsFile)
        return getModelsFromModelsFile()
    }
    log.Debugf("Fetching models from the internet")
    models, err := getModelsFromInternet()
    if len(models) != 0 && err == nil {
        models.SaveModelsFile()
    }
    return models, err
}

// FilterByName filters models by name
func (m Models) FilterByName(query string) Models {
    output := Models{}
    for _, synoModel := range m {
        if strings.Contains(strings.ToLower(synoModel.Name), strings.ToLower(query)) {
            output = append(output, synoModel)
        }
    }
    return output
}

// SaveModelsFile saves the model file to o.ModelsFile
func (m Models) SaveModelsFile() error {
    yamlModels, err := yaml.Marshal(m)
    if err != nil {
        return err
    }
    err = os.WriteFile(o.ModelsFile, yamlModels, 0755)
    if err != nil {
        return err
    }
    log.Debugf("Saved models to %s", o.ModelsFile)
    return nil
}

func modelsFileExists() bool {
    if _, err := os.Stat(o.ModelsFile); os.IsNotExist(err) {
        return false
    }
    return true
}

func getModelsFromModelsFile() (Models, error) {
    var models Models
    bytes, err := os.ReadFile(o.ModelsFile)
    if err != nil {
        return nil, err
    }

    if yaml.Unmarshal(bytes, &models); err != nil {
        return nil, err
    }
    return models, nil
}

// getModelsFromInternet fetches Synology models from
// The official Synology kb
func getModelsFromInternet() (Models, error) {
    resp, err := http.Get("https://kb.synology.com/en-me/DSM/tutorial/What_kind_of_CPU_does_my_NAS_have")
    if err != nil && resp != nil && resp.StatusCode != 200 && resp.StatusCode != 302 {
        return nil, err
    }

    doc, err := goquery.NewDocumentFromReader(resp.Body)
    if err != nil {
        return nil, err
    }

    // All the html we want is embedded in the last <script> tag
    var lastDeferedScript string
    doc.Find("script[defer]").Each(func(i int, s *goquery.Selection) {
        lastDeferedScript = s.Text()
    })

    // Extract the content capture group
    r := regexp.MustCompile(`"content":"(.*)","tags"`)
    match := r.FindStringSubmatch(lastDeferedScript)[1]

    // Let otto handle the double quoted JS from content
    vm := otto.New()
    inlineHtml, err := vm.Run(`"` + match + `"`)
    if err != nil {
        return nil, err
    }

    // New sub document to parse inline HTML
    subDoc, err := goquery.NewDocumentFromReader(strings.NewReader(inlineHtml.String()))
    if err != nil {
        return nil, err
    }

    var models Models

    subDoc.Find("tr").Each(func(i int, s *goquery.Selection) {
        tds := s.ChildrenFiltered("td")
        if tds.Size() == 7 {
            model := &Model{
                Name:    tds.Eq(0).Text(),
                CPU:     tds.Eq(1).Text(),
                Cores:   tds.Eq(2).Text(),
                Threads: tds.Eq(3).Text(),
                FPU:     tds.Eq(4).Text(),
                Arch:    tds.Eq(5).Text(),
                RAM:     tds.Eq(6).Text(),
            }
            models = append(models, model)
        }
    })
    return models, nil
}