adds findDOHEndpoint() for given zone to JS API

golang/sig0/doh.go

@@ -64,6 +64,7 @@ func FindDOHEndpoint(name string) (*url.URL, error) {
  return nil, fmt.Errorf("findDOHEndpoint: no answer section for %s", lookup)
  }
 
+ // TODO deal with more than one SVCB "_dns." + name in RRSet
  first := answer.Answer[0]
  svcb, ok := first.(*dns.SVCB)
  if !ok {

golang/wasm/pure.js

@@ -184,3 +184,30 @@ function getKeysForDomain() {
 
  return
 }
+
+// findDOHEndpoint()
+// for a given domain, find DOH Endpoint URL for update returned as string
+//
+async function findDOHEndpoint() {
+ var dohDomain = document.getElementById("doh-for-domain").value
+ if (! dohDomain.endsWith('.')) {
+ dohDomain = dohDomain + '.'
+ }
+
+ const div = document.getElementById("domain-doh-endpoint")
+ if (div.children.length > 0) {
+ div.removeChild(div.children[0])
+ }
+
+ const ul = document.createElement("ul")
+
+ const dohEndpoint = window.goFuncs.findDOHEndpoint
+ k = await dohEndpoint(dohDomain)
+ const li = document.createElement("li")
+ li.innerHTML = k
+ ul.appendChild(li)
+
+ div.appendChild(ul)
+
+ return
+}

golang/wasm/wasm_exec.html

@@ -24,6 +24,12 @@ <h3>Search Keystore for Key to sign update for a given Subdomain</h3>
  <button onclick="getKeysForDomain()">Find key in keystore</button>
  <div id="domain-key"></div>
  </p>
+ <h3>Find DOH Endpoint for a given Subdomain</h3>
+ <p>
+ <input type="text" id="doh-for-domain" placeholder="mythingymajig.zenr.io">
+ <button onclick="findDOHEndpoint()">Find DOH endpoint</button>
+ <div id="domain-doh-endpoint"></div>
+ </p>
  <h3>Import Key pair files from filesystem into Browser Keystore</h3>
  <p>
  <input type="file" id="input-key" accept=".key"/>

golang/wasm/wrapper_js.go

@@ -25,6 +25,7 @@ func main() {
  goFuncs.Set("newKeyRequest", js.FuncOf(newKeyRequest))
  goFuncs.Set("newUpdater", js.FuncOf(newUpdater))
  goFuncs.Set("checkKeyStatus", js.FuncOf(checkKeyStatus))
+ goFuncs.Set("findDOHEndpoint", js.FuncOf(findDOHEndpoint))
 
  // cant let main return
  forever := make(chan bool)
@@ -208,6 +209,34 @@ func checkKeyStatus(_ js.Value, args []js.Value) any {
  return promiseConstructor.New(handler)
 }
 
+func findDOHEndpoint(_ js.Value, args []js.Value) any {
+ if len(args) != 1 {
+ return "expected 1 argument: domainName"
+ }
+ dohDomain := args[0].String()
+
+ handler := js.FuncOf(func(this js.Value, args []js.Value) interface{} {
+ resolve := args[0]
+ reject := args[1]
+
+ go func() {
+ // Note sig0.FindDOHEnpoint returns single cooked value from first SVCB RR resolved
+ dohUrl, err := sig0.FindDOHEndpoint(dohDomain)
+ if err != nil {
+ reject.Invoke(jsErr(err))
+ return
+ }
+ resolve.Invoke(dohUrl.String())
+ }()
+
+ return nil
+ })
+
+ promiseConstructor := js.Global().Get("Promise")
+ return promiseConstructor.New(handler)
+
+}
+
 // create a keypair and request a key
 // arguments: the name to request
 // returns nill or an error string