feat(deploy-toolbar): improve error handling

* use endpoint url provided by client
* display user-friendly error messages
* do not throw error for response other than JSON

Closes #838

app/lib/createDeployer.js

@@ -8,55 +8,74 @@ function createDeployer({ fetch, fs, FormData }) {
   /**
    * Deploy diagram to the given endpoint URL.
    */
-  return function deploy(url, { deploymentName, tenantId, file = {} }, cb) {
+  return async function deploy(url, { deploymentName, tenantId, file = {} }, cb) {
 
-    // callback is optional
-    cb = cb || noop;
+    try {
+      // callback is optional
+      cb = cb || noop;
 
-    if (!deploymentName) {
-      return cb(
-        new Error(
-          'Failed to deploy process, deployment name must be provided.'
-        )
-      );
-    }
+      if (!deploymentName) {
+        throw new Error('Failed to deploy process, deployment name must be provided.');
+      }
 
-    if (!file.fileType || !file.name || !file.path) {
-      return cb(
-        new Error(
-          'Failed to deploy process, file name and path must be provided.'
-        )
-      );
-    }
+      if (!file.name || !file.path) {
+        throw new Error('Failed to deploy process, file name and path must be provided.');
+      }
 
-    if (!url) {
-      return cb(
-        new Error(
-          'Failed to deploy process, endpoint url must not be empty.'
-        )
-      );
-    }
+      if (!url) {
+        throw new Error('Failed to deploy process, endpoint url must not be empty.');
+      }
 
-    const form = new FormData();
+      const form = new FormData();
 
-    form.append('deployment-name', deploymentName);
+      form.append('deployment-name', deploymentName);
 
-    if (tenantId) {
-      form.append('tenant-id', tenantId);
-    }
+      if (tenantId) {
+        form.append('tenant-id', tenantId);
+      }
+
+      form.append(file.name, fs.createReadStream(file.path));
+
+      const serverResponse = await fetch(url, { method: 'POST', body: form });
+
+      if (!serverResponse.ok) {
+        const error = await getErrorFromResponse(serverResponse);
+        throw error;
+      }
+
+      let response;
 
-    form.append(file.name, fs.createReadStream(file.path));
+      try {
+        response = await serverResponse.json();
+      } catch (error) {
+        response = serverResponse.statusText;
+      }
+
+      return cb(null, response);
+    } catch (error) {
+      return cb(error);
+    }
 
-    fetch(url, { method: 'POST', body: form })
-      .then(res => res.json())
-      .then(json => cb(null, json))
-      .catch(function(error) {
-        cb(error);
-      });
   };
 }
 
 module.exports = createDeployer;
 
 
-function noop() { }
+// helpers //////
+function noop() { }
+
+
+async function getErrorFromResponse(response) {
+  const error = new Error();
+
+  try {
+    const body = await response.json();
+    error.message = body.message;
+  } catch (_) {
+    error.code = response.status;
+    error.message = response.statusText;
+  }
+
+  return error;
+}

app/lib/index.js

@@ -167,31 +167,7 @@ renderer.on('dialog:show', async function(options, done) {
 // deploying //////////
 // TODO: remove and add as plugin instead
 
-renderer.on('deploy', function(data, done) {
-  var workspaceConfig = config.get('workspace', { endpoints: [] });
-
-  var endpointUrl = (workspaceConfig.endpoints || [])[0];
-
-  if (!endpointUrl) {
-
-    let err = new Error('no deploy endpoint configured');
-
-    console.error('failed to deploy', err);
-    return done(err.message);
-  }
-
-  deploy(endpointUrl, data, function(err, result) {
-
-    if (err) {
-      console.error('failed to deploy', err);
-
-      return done(err.message);
-    }
-
-    done(null, result);
-  });
-
-});
+renderer.on('deploy', handleDeployment);
 
 // filesystem //////////
 
@@ -430,5 +406,20 @@ app.on('ready', function() {
 });
 
 
+function handleDeployment(data, done) {
+  const { endpointUrl } = data;
+
+  deploy(endpointUrl, data, function(error, result) {
+
+    if (error) {
+      console.error('failed to deploy', error);
+
+      return done(error);
+    }
+
+    done(null, result);
+  });
+}
+
 // expose app
 module.exports = app;

app/lib/util/renderer.js

@@ -5,7 +5,8 @@ var electron = require('electron'),
     app = electron.app;
 
 const {
-  assign
+  assign,
+  pick
 } = require('min-dash');
 
 
@@ -15,8 +16,9 @@ function on(event, callback, that) {
 
     function done(...doneArgs) {
       var actualArgs = doneArgs.map(function(e) {
+        // error.message and error.code are not enumerable
         if (e instanceof Error) {
-          return assign({}, e);
+          return assign({}, pick(e, [ 'message', 'code' ]), e);
         }
 
         return e;

app/test/helper/mock/fetch.js

@@ -2,6 +2,7 @@ var RESPONSE_OK = { mocked: true };
 
 module.exports = function(url, options) {
   return Promise.resolve({
+    ok: true,
     json: () => Promise.resolve(RESPONSE_OK)
   });
 };