Fix API errors when handling nil pointers to structs.

api/client.js

@@ -94,6 +94,79 @@ function connect(url, options={}, callback) {
 }
 
 
+/**
+  Connect to the Juju controller or model at the given URL and the authenticate
+  using the given credentials.
+
+  @param {String} url The WebSocket URL of the Juju controller or model.
+  @param {Object} credentials An object with the user and password fields for
+    userpass authentication or the macaroons field for bakery authentication.
+    If an empty object is provided a full bakery discharge will be attempted
+    for logging in with macaroons. Any necessary third party discharges are
+    performed using the bakery instance provided in the options (see below).
+  @param {Object} options Connections options, including:
+    - facades (default=[]): the list of facade classes to include in the API
+      connection object. Those classes are usually auto-generated and can be
+      found in the facades directory of the project. When multiple versions of
+      the same facade are included, the most recent version supported by the
+      server is made available as part of the connection object;
+    - debug (default=false): when enabled, all API messages are logged at debug
+      level;
+    - wsclass (default=W3C browser native WebSocket): the WebSocket class to use
+      for opening the connection and sending/receiving messages. Server side,
+      require('websocket').w3cwebsocket can be used safely, as it implements the
+      W3C browser native WebSocket API;
+    - bakery (default: null): the bakery client to use when macaroon discharges
+      are required, in the case an external user is used to connect to Juju;
+      see <https://www.npmjs.com/package/macaroon-bakery>;
+    - closeCallback: a callback to be called with the exit code when the
+      connection is closed.
+  @param {Function} callback Called when the login process completes, the
+    callback receives an error, a connection object and a logout function that
+    can be used to clos ethe connection. If there are no errors, the connection
+    can be used to send/receive messages to and from the Juju controller or
+    model, and to get access to the available facades (through conn.facades).
+    See the docstring for the Connection class for information on how to use
+    the connection instance. Redirection errors are automatically handled by
+    this function, so any error is a real connection problem.
+*/
+function connectAndLogin(url, credentials, options, callback) {
+  // Connect to Juju.
+  connect(url, options, (err, juju) => {
+    if (err) {
+      callback(err, null, null);
+      return;
+    }
+    // Authenticate.
+    juju.login(credentials, (err, conn) => {
+      if (!err) {
+        callback(null, conn, juju.logout.bind(juju));
+        return;
+      }
+      if (!juju.isRedirectionError(err)) {
+        callback(err, null, null);
+        return;
+      }
+      // Redirect to the real model.
+      juju.logout();
+      for (let i = 0; i < err.servers.length; i++) {
+        const srv = err.servers[i];
+        // TODO(frankban): we should really try to connect to all servers and
+        // just use the first connection available, without second guessing
+        // that the public hostname is reachable.
+        if (srv.type === 'hostname' && srv.scope === 'public') {
+          // This is a public server with a dns-name, connect to it.
+          connectAndLogin(srv.url(url), credentials, options, callback);
+          return;
+        }
+      }
+      callback(
+        new Error('cannot connect to model after redirection'), null, null);
+    });
+  });
+}
+
+
 /**
   A Juju API client allowing for logging in and get access to facades.
 
@@ -392,4 +465,4 @@ function uncapitalize(string) {
 }
 
 
-module.exports = {connect: connect};
+module.exports = {connect, connectAndLogin};

api/test-client.js

@@ -94,10 +94,16 @@ tap.test('connect', t => {
         t.equal(
           err.servers[0].url('srv1-uuid'),
           'wss://1.2.3.4:17070/model/srv1-uuid/api');
+        t.equal(
+          err.servers[0].url('wss://4.3.2.1:443/model/uuid-in-url/api'),
+          'wss://1.2.3.4:17070/model/uuid-in-url/api');
         t.equal(err.servers[1].value, 'example.com');
         t.equal(err.servers[1].port, 443);
         t.equal(err.servers[1].type, 'hostname');
         t.equal(err.servers[1].scope, 'global');
+        t.equal(
+          err.servers[1].url('ws://4.3.2.1:443/model/another/api'),
+          'wss://example.com:443/model/another/api');
         t.equal(
           err.servers[1].url('srv2-uuid'),
           'wss://example.com:443/model/srv2-uuid/api');
@@ -299,3 +305,123 @@ tap.test('connect', t => {
 
   t.end();
 });
+
+
+tap.test('connectAndLogin', t => {
+  let ws;
+  const url = 'wss://1.2.3.4';
+  const options = {
+    wsclass: helpers.makeWSClass(instance => {
+      ws = instance;
+    })
+  };
+
+  t.test('connect failure', t => {
+    const creds = {};
+    jujulib.connectAndLogin(url, creds, options, (err, conn, logout) => {
+      t.equal(err, 'cannot connect WebSocket: bad wolf');
+      t.equal(conn, null);
+      t.equal(logout, null);
+      t.end();
+    });
+    // Close the WebSocket connection.
+    ws.close('bad wolf');
+  });
+
+  t.test('login failure', t => {
+    const creds = {user: 'who', password: 'tardis'};
+    jujulib.connectAndLogin(url, creds, options, (err, conn, logout) => {
+      helpers.requestEqual(t, ws.lastRequest, {
+        type: 'Admin',
+        request: 'Login',
+        params: {'auth-tag': 'who', credentials: 'tardis', macaroons: []},
+        version: 3
+      });
+      t.equal(err, 'bad wolf');
+      t.equal(conn, null);
+      t.equal(logout, null);
+      t.end();
+    });
+    // Open the WebSocket connection.
+    ws.open();
+    // Reply to the login request.
+    ws.reply({error: 'bad wolf'});
+  });
+
+  t.test('login redirection error failure', t => {
+    const creds = {user: 'who', password: 'tardis'};
+    jujulib.connectAndLogin(url, creds, options, (err, conn, logout) => {
+      helpers.requestEqual(t, ws.lastRequest, {
+        type: 'Admin',
+        request: 'RedirectInfo',
+        params: {},
+        version: 3
+      });
+      t.equal(err, 'bad wolf');
+      t.equal(conn, null);
+      t.equal(logout, null);
+      t.end();
+    });
+    // Open the WebSocket connection.
+    ws.open();
+    // Reply to the login request.
+    ws.reply({error: 'redirection required'});
+    // Reply to the redirectInfo request.
+    ws.reply({error: 'bad wolf'});
+  });
+
+  t.test('login redirection error success', t => {
+    const creds = {user: 'who', password: 'tardis'};
+    jujulib.connectAndLogin(url, creds, options, (err, conn, logout) => {
+      t.equal(err, null);
+      t.notEqual(conn, null);
+      t.notEqual(logout, null);
+      logout();
+      // The WebSocket is now closed.
+      t.equal(ws.readyState, 3);
+      t.end();
+    });
+    // Open the WebSocket connection.
+    ws.open();
+    // Reply to the login request.
+    ws.reply({error: 'redirection required'});
+    // Reply to the redirectInfo request.
+    ws.reply({response: {
+      'ca-cert': 'mycert',
+      'servers': [[{
+        value: '1.2.3.4',
+        port: 17070,
+        type: 'ipv4',
+        scope: 'public'
+      }, {
+        value: 'example.com',
+        port: 443,
+        type: 'hostname',
+        scope: 'public'
+      }]]
+    }});
+    // Open the new WebSocket connection.
+    ws.open();
+    // Reply to the new login request.
+    ws.reply({});
+  });
+
+  t.test('login success', t => {
+    const creds = {user: 'who', password: 'tardis'};
+    jujulib.connectAndLogin(url, creds, options, (err, conn, logout) => {
+      t.equal(err, null);
+      t.notEqual(conn, null);
+      t.notEqual(logout, null);
+      logout();
+      // The WebSocket is now closed.
+      t.equal(ws.readyState, 3);
+      t.end();
+    });
+    // Open the WebSocket connection.
+    ws.open();
+    // Reply to the login request.
+    ws.reply({});
+  });
+
+  t.end();
+});

api/test-helpers.js

@@ -50,11 +50,15 @@ const loginResponse = {
     'model-access': 'admin'
   },
   facades: [{
+    name: 'AllModelWatcher', versions: [1]
+  }, {
     name: 'AllWatcher', versions: [0]
   }, {
     name: 'Application', versions: [7]
   }, {
     name: 'Client', versions: [2, 3]
+  }, {
+    name: 'Controller', versions: [3, 4, 5]
   }, {
     name: 'MyFacade', versions: [1, 7]
   }]
@@ -109,6 +113,7 @@ class WebSocket {
   }
 
   close(reason) {
+    this.readyState = 3;
     this.onclose({reason: reason});
   }