feat: /api/v0/dns

Author: hacdias

.gitignore

@@ -40,3 +40,4 @@ test/test-data/go-ipfs-repo/LOG.old
 
 # while testing npm5
 package-lock.json
+yarn.lock

package.json

@@ -11,6 +11,7 @@
     "./src/core/runtime/config-nodejs.json": "./src/core/runtime/config-browser.json",
     "./src/core/runtime/libp2p-nodejs.js": "./src/core/runtime/libp2p-browser.js",
     "./src/core/runtime/repo-nodejs.js": "./src/core/runtime/repo-browser.js",
+    "./src/core/runtime/dns-nodejs.js": "./src/core/runtime/dns-browser.js",
     "./test/utils/create-repo-nodejs.js": "./test/utils/create-repo-browser.js",
     "stream": "readable-stream"
   },

src/cli/commands/dns.js

@@ -0,0 +1,24 @@
+'use strict'
+const print = require('../utils').print
+
+module.exports = {
+  command: 'dns <domain>',
+
+  describe: 'Resolve DNS links',
+
+  builder: {
+    format: {
+      type: 'string'
+    }
+  },
+
+  handler (argv) {
+    argv.ipfs.dns(argv['domain'], (err, path) => {
+      if (err) {
+        throw err
+      }
+
+      print(path)
+    })
+  }
+}

src/core/components/dns.js

@@ -0,0 +1,20 @@
+'use strict'
+
+// dns-nodejs gets replaced by dns-browser when webpacked/browserified
+const dns = require('../runtime/dns-nodejs')
+const promisify = require('promisify-es6')
+
+module.exports = () => {
+  return promisify((domain, opts, callback) => {
+    if (typeof domain !== 'string') {
+      return callback(new Error('Invalid arguments, domain must be a string'))
+    }
+
+    if (typeof opts === 'function') {
+      callback = opts
+      opts = {}
+    }
+
+    dns(domain, opts, callback)
+  })
+}

src/core/components/index.js

@@ -20,3 +20,4 @@ exports.files = require('./files')
 exports.bitswap = require('./bitswap')
 exports.pubsub = require('./pubsub')
 exports.dht = require('./dht')
+exports.dns = require('./dns')

src/core/index.js

@@ -94,6 +94,7 @@ class IPFS extends EventEmitter {
     this.ping = components.ping(this)
     this.pubsub = components.pubsub(this)
     this.dht = components.dht(this)
+    this.dns = components.dns(this)
 
     if (this._options.EXPERIMENTAL.pubsub) {
       this.log('EXPERIMENTAL pubsub is enabled')

src/core/runtime/dns-browser.js

@@ -0,0 +1,25 @@
+'use strict'
+
+module.exports = (domain, opts, callback) => {
+  domain = encodeURIComponent(domain)
+  let url = `https://ipfs.io/api/v0/dns?arg=${domain}`
+
+  for (const prop in opts) {
+    url += `&${prop}=${opts[prop]}`
+  }
+
+  window.fetch(url, {mode: 'cors'})
+    .then((response) => {
+      return response.json()
+    })
+    .then((response) => {
+      if (response.Path) {
+        return callback(null, response.Path)
+      } else {
+        return callback(new Error(response.Message))
+      }
+    })
+    .catch((error) => {
+      callback(error)
+    })
+}

src/core/runtime/dns-nodejs.js

@@ -0,0 +1,21 @@
+'use strict'
+
+const dns = require('dns')
+
+module.exports = (domain, opts, callback) => {
+  dns.resolveTxt(domain, (err, records) => {
+    if (err) {
+      return callback(err, null)
+    }
+
+    // TODO: implement recursive option
+
+    for (const record of records) {
+      if (record[0].startsWith('dnslink=')) {
+        return callback(null, record[0].substr(8, record[0].length - 1))
+      }
+    }
+
+    callback(new Error('domain does not have a txt dnslink entry'))
+  })
+}

src/http/api/resources/dns.js

@@ -0,0 +1,24 @@
+'use strict'
+
+const boom = require('boom')
+
+exports = module.exports
+
+exports.get = (request, reply) => {
+  if (!request.query.arg) {
+    return reply({
+      Message: "Argument 'domain' is required",
+      Code: 0
+    }).code(400).takeover()
+  }
+
+  request.server.app.ipfs.dns(request.query.arg, (err, path) => {
+    if (err) {
+      return reply(boom.badRequest(err))
+    }
+
+    return reply({
+      Path: path
+    })
+  })
+}

src/http/api/resources/index.js

@@ -12,3 +12,4 @@ exports.bitswap = require('./bitswap')
 exports.file = require('./file')
 exports.files = require('./files')
 exports.pubsub = require('./pubsub')
+exports.dns = require('./dns')