diff --git a/README.md b/README.md index f6aa77b..31bc51c 100644 --- a/README.md +++ b/README.md @@ -1,12 +1,16 @@ # DIGITAL OCEAN DYNAMIC IP API CLIENT A simple script in Go language to automatically update Digital ocean DNS records if you have a dynamic IP. Since it can be compiled on any platform, you can use it along with raspberrypi etc. +To find your Dynamic IP, this program will call out to https://diagnostic.opendns.com/myip. + ## requirements Requires Git and Go for building. Requires that the record already exists in DigitalOcean's DNS so that it can be updated. (manually find your IP and add it to DO's DNS it will later be updated) +Requires a Digital Ocean API key that can be created at https://cloud.digitalocean.com/account/api/tokens. + ## Usage ```bash git clone https://github.com/anaganisk/digitalocean-dynamic-dns-ip.git @@ -16,6 +20,7 @@ create a file ".digitalocean-dynamic-ip.json"(dot prefix to hide the file) and p ```json { "apikey": "samplekeydasjkdhaskjdhrwofihsamplekey", + "doPageSize" : 20, "domains": [ { "domain": "example.com", @@ -31,18 +36,30 @@ create a file ".digitalocean-dynamic-ip.json"(dot prefix to hide the file) and p "records": [ { "name": "subdomainOrRecord2", - "type": "A" + "type": "A", + "TTL": 30 } ] } ] } ``` +The TTL can optionally be updated if passed in the configuration. Digital Ocean has a minimum TTL of 30 seconds. The `type` and the `name` must match existing records in the Digital Ocean DNS configuration. Only `types` of `A` and `AAAA` allowed at the moment. + +If you want to reduce the number of calls made to the digital ocean API and have more than 20 DNS records in your domain, you can adjust the `doPageSize` parameter. By default, Digital Ocean returns 20 records per page. + ```bash #run go build digitalocean-dynamic-ip.go ./digitalocean-dynamic-ip ``` + +Optionally, you can create the configuration file with any name wherever you want, and pass it as a command line argument: +````bash +#run +./digitalocean-dynamic-ip /path/tp/my/config.json +``` + You can either set this to run periodically with a cronjob or use your own method. ```bash # run crontab -e diff --git a/digitalocean-dynamic-ip.go b/digitalocean-dynamic-ip.go index 3df31c3..593b91e 100644 --- a/digitalocean-dynamic-ip.go +++ b/digitalocean-dynamic-ip.go @@ -3,9 +3,14 @@ package main import ( "bytes" "encoding/json" + "flag" + "fmt" "io/ioutil" "log" + "net" "net/http" + "net/url" + "os" "strconv" homedir "github.com/mitchellh/go-homedir" @@ -17,10 +22,13 @@ func checkError(err error) { } } +var config ClientConfig + // ClientConfig : configuration json type ClientConfig struct { - APIKey string `json:"apiKey"` - Domains []Domain `json:"domains"` + APIKey string `json:"apiKey"` + DOPageSize int `json:"doPageSize"` + Domains []Domain `json:"domains"` } // Domain : domains to be changed @@ -31,22 +39,56 @@ type Domain struct { // DNSRecord : Modifyiable DNS record type DNSRecord struct { - ID int64 `json:"id"` - Name string `json:"name"` - Data string `json:"data"` - Type string `json:"type"` + ID int64 `json:"id"` + Type string `json:"type"` + Name string `json:"name"` + Priority *int `json:"priority"` + Port *int `json:"port"` + Weight *int `json:"weight"` + TTL int `json:"ttl"` + Flags *uint8 `json:"flags"` + Tag *string `json:"tag"` + Data string `json:"data"` } // DOResponse : DigitalOcean DNS Records response. type DOResponse struct { DomainRecords []DNSRecord `json:"domain_records"` + Meta struct { + Total int `json:"total"` + } `json:"meta"` + Links struct { + Pages struct { + First string `json:"first"` + Previous string `json:"prev"` + Next string `json:"next"` + Last string `json:"last"` + } `json:"pages"` + } `json:"links"` } //GetConfig : get configuration file ~/.digitalocean-dynamic-ip.json func GetConfig() ClientConfig { - homeDirectory, err := homedir.Dir() - checkError(err) - getfile, err := ioutil.ReadFile(homeDirectory + "/.digitalocean-dynamic-ip.json") + cmdHelp := flag.Bool("h", false, "Show the help message") + cmdHelp2 := flag.Bool("help", false, "Show the help message") + flag.Parse() + + if *cmdHelp || *cmdHelp2 { + usage() + os.Exit(1) + } + + configFile := "" + if len(flag.Args()) == 0 { + var err error + configFile, err = homedir.Dir() + checkError(err) + configFile += "/.digitalocean-dynamic-ip.json" + } else { + configFile = flag.Args()[0] + } + + getfile, err := ioutil.ReadFile(configFile) checkError(err) var config ClientConfig json.Unmarshal(getfile, &config) @@ -54,6 +96,21 @@ func GetConfig() ClientConfig { return config } +func usage() { + os.Stdout.WriteString(fmt.Sprintf("To use this program you can specify the following command options:\n"+ + "-h | -help\n\tShow this help message\n"+ + "[config_file]\n\tlocation of the configuration file\n\n"+ + "If the [config_file] parameter is not passed, then the default\n"+ + "config location of ~/.digitalocean-dynamic-ip.json will be used.\n\n"+ + "example usages:\n\t%[1]s -help\n"+ + "\t%[1]s\n"+ + "\t%[1]s %[2]s\n"+ + "", + os.Args[0], + "/path/to/my/config.json", + )) +} + //CheckLocalIP : get current IP of server. func CheckLocalIP() string { currentIPRequest, err := http.Get("https://diagnostic.opendns.com/myip") @@ -65,18 +122,33 @@ func CheckLocalIP() string { } //GetDomainRecords : Get DNS records of current domain. -func GetDomainRecords(apiKey string, domain string) DOResponse { +func GetDomainRecords(domain string) []DNSRecord { + ret := make([]DNSRecord, 0) + var page DOResponse + pageParam := "" + // 20 is the default page size + if config.DOPageSize > 0 && config.DOPageSize != 20 { + pageParam = "?per_page=" + strconv.Itoa(config.DOPageSize) + } + for url := "https://api.digitalocean.com/v2/domains/" + url.PathEscape(domain) + "/records" + pageParam; url != ""; url = page.Links.Pages.Next { + page = getPage(url) + ret = append(ret, page.DomainRecords...) + } + return ret +} + +func getPage(url string) DOResponse { + log.Println(url) client := &http.Client{} - request, err := http.NewRequest("GET", - "https://api.digitalocean.com/v2/domains/"+domain+"/records", - nil) + request, err := http.NewRequest("GET", url, nil) checkError(err) request.Header.Add("Content-type", "Application/json") - request.Header.Add("Authorization", "Bearer "+apiKey) + request.Header.Add("Authorization", "Bearer "+config.APIKey) response, err := client.Do(request) checkError(err) defer response.Body.Close() body, err := ioutil.ReadAll(response.Body) + // log.Print(string(body)) var jsonDOResponse DOResponse e := json.Unmarshal(body, &jsonDOResponse) checkError(e) @@ -84,37 +156,84 @@ func GetDomainRecords(apiKey string, domain string) DOResponse { } // UpdateRecords : Update DNS records of domain -func UpdateRecords(apiKey string, domain string, currentIP string, currentRecords DOResponse, toUpdateRecords []DNSRecord) { - for _, currentRecord := range currentRecords.DomainRecords { - for _, toUpdateRecord := range toUpdateRecords { - if toUpdateRecord.Name == currentRecord.Name && toUpdateRecord.Type == currentRecord.Type && currentIP != currentRecord.Data { - update := []byte(`{"type":"` + toUpdateRecord.Type + `","data":"` + currentIP + `"}`) +func UpdateRecords(domain string, ip net.IP, toUpdateRecords []DNSRecord) { + currentIP := ip.String() + isIpv6 := ip.To4() == nil + if !isIpv6 { + // make sure we are using a v4 format + currentIP = ip.To4().String() + } + log.Printf("%s: %d to update\n", domain, len(toUpdateRecords)) + updated := 0 + doRecords := GetDomainRecords(domain) + // look for the item to update + if len(doRecords) < 1 { + log.Printf("%s: No DNS records found", domain) + return + } + log.Printf("%s: %d DNS records found", domain, len(doRecords)) + for _, toUpdateRecord := range toUpdateRecords { + if toUpdateRecord.Type != "A" && toUpdateRecord.Type != "AAAA" { + log.Fatalf("%s: Unsupported type (Only A and AAAA records supported) for updates %+v", domain, toUpdateRecord) + } + if isIpv6 && toUpdateRecord.Type == "A" { + log.Fatalf("%s: You are trying to update an IPV4 A record with an IPV6 address: new ip: %s, config: %+v", domain, currentIP, toUpdateRecord) + } + if !isIpv6 && toUpdateRecord.Type == "AAAA" { + log.Fatalf("%s: You are trying to update an IPV6 A record with an IPV4 address: new ip: %s, config: %+v", domain, currentIP, toUpdateRecord) + } + if toUpdateRecord.ID > 0 { + // update the record directly. skip the extra search + log.Fatalf("%s: Unable to directly update records yet. Record: %+v", domain, toUpdateRecord) + } + + log.Printf("%s: trying to update `%s` : `%s`", domain, toUpdateRecord.Type, toUpdateRecord.Name) + for _, doRecord := range doRecords { + //log.Printf("%s: checking `%s` : `%s`", domain, doRecord.Type, doRecord.Name) + if doRecord.Name == toUpdateRecord.Name && doRecord.Type == toUpdateRecord.Type { + if doRecord.Data == currentIP && (toUpdateRecord.TTL < 30 || doRecord.TTL == toUpdateRecord.TTL) { + log.Printf("%s: IP/TTL did not change %+v", domain, doRecord) + continue + } + log.Printf("%s: updating %+v", domain, doRecord) + // set the IP address + doRecord.Data = currentIP + if toUpdateRecord.TTL >= 30 && doRecord.TTL != toUpdateRecord.TTL { + doRecord.TTL = toUpdateRecord.TTL + } + update, err := json.Marshal(doRecord) + checkError(err) client := &http.Client{} request, err := http.NewRequest("PUT", - "https://api.digitalocean.com/v2/domains/"+domain+"/records/"+strconv.FormatInt(int64(currentRecord.ID), 10), + "https://api.digitalocean.com/v2/domains/"+url.PathEscape(domain)+"/records/"+strconv.FormatInt(int64(doRecord.ID), 10), bytes.NewBuffer(update)) checkError(err) request.Header.Set("Content-Type", "application/json") - request.Header.Add("Authorization", "Bearer "+apiKey) + request.Header.Add("Authorization", "Bearer "+config.APIKey) response, err := client.Do(request) checkError(err) defer response.Body.Close() body, err := ioutil.ReadAll(response.Body) - log.Printf("DO update response for %s: %s\n", currentRecord.Name, string(body)) + log.Printf("%s: DO update response for %s: %s\n", domain, doRecord.Name, string(body)) + updated++ } } + } + log.Printf("%s: %d of %d records updated\n", domain, updated, len(toUpdateRecords)) } func main() { - config := GetConfig() + config = GetConfig() currentIP := CheckLocalIP() - - for _, domains := range config.Domains { - domainName := domains.Domain - apiKey := config.APIKey - currentDomainRecords := GetDomainRecords(apiKey, domainName) - log.Println(domainName) - UpdateRecords(apiKey, domainName, currentIP, currentDomainRecords, domains.Records) + ip := net.ParseIP(currentIP) + if ip == nil { + log.Fatalf("current IP address `%s` is not a valid IP address", currentIP) + } + for _, domain := range config.Domains { + domainName := domain.Domain + log.Printf("%s: START\n", domainName) + UpdateRecords(domainName, ip, domain.Records) + log.Printf("%s: END\n", domainName) } } diff --git a/digitalocean-dynamic-ip.sample.json b/digitalocean-dynamic-ip.sample.json index f9fae24..5db66a9 100644 --- a/digitalocean-dynamic-ip.sample.json +++ b/digitalocean-dynamic-ip.sample.json @@ -1,5 +1,6 @@ { "apikey": "samplekeydasjkdhaskjdhrwofihsamplekey", + "doPageSize" : 20, "domains": [ { "domain": "example.com",