Refactor server dialogue validation for better unit testing.

Victoria & Joao @ Pivotal.

web/pgadmin/static/js/browser/server_groups/index.js

@@ -0,0 +1,10 @@
+/////////////////////////////////////////////////////////////
+//
+// pgAdmin 4 - PostgreSQL Tools
+//
+// Copyright (C) 2013 - 2018, The pgAdmin Development Team
+// This software is released under the PostgreSQL Licence
+//
+//////////////////////////////////////////////////////////////
+
+import 'servers';

web/pgadmin/static/js/browser/server_groups/servers/databases/index.js

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+/////////////////////////////////////////////////////////////
+//
+// pgAdmin 4 - PostgreSQL Tools
+//
+// Copyright (C) 2013 - 2018, The pgAdmin Development Team
+// This software is released under the PostgreSQL Licence
+//
+//////////////////////////////////////////////////////////////
+
+import 'external_tables';

web/pgadmin/static/js/browser/server_groups/servers/index.js

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+/////////////////////////////////////////////////////////////
+//
+// pgAdmin 4 - PostgreSQL Tools
+//
+// Copyright (C) 2013 - 2018, The pgAdmin Development Team
+// This software is released under the PostgreSQL Licence
+//
+//////////////////////////////////////////////////////////////
+
+import 'databases';
+import 'model_validation';

web/pgadmin/static/js/browser/server_groups/servers/model_validation.js

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+/////////////////////////////////////////////////////////////
+//
+// pgAdmin 4 - PostgreSQL Tools
+//
+// Copyright (C) 2013 - 2018, The pgAdmin Development Team
+// This software is released under the PostgreSQL Licence
+//
+//////////////////////////////////////////////////////////////
+
+import gettext from 'sources/gettext';
+import _ from 'underscore';
+import {Address4, Address6} from 'ip-address';
+
+export class ModelValidation {
+  constructor(model) {
+    this.err = {};
+    this.errmsg = '';
+    this.model = model;
+  }
+
+  validate() {
+    const serviceId = this.model.get('service');
+
+    if (!this.model.isNew() && 'id' in this.model.sessAttrs) {
+      this.err['id'] = gettext('The ID cannot be changed.');
+      this.errmsg = this.err['id'];
+    } else {
+      this.model.errorModel.unset('id');
+    }
+
+    this.checkForEmpty('name', gettext('Name must be specified.'));
+
+    if (ModelValidation.isEmptyString(serviceId)) {
+      this.checkHostAndHostAddress();
+
+      this.checkForEmpty('db', gettext('Maintenance database must be specified.'));
+    } else {
+      this.clearHostAddressAndDbErrors();
+    }
+
+    this.checkForEmpty('username', gettext('Username must be specified.'));
+    this.checkForEmpty('port', gettext('Port must be specified.'));
+
+    this.model.errorModel.set(this.err);
+
+    if (_.size(this.err)) {
+      return this.errmsg;
+    }
+
+    return null;
+  }
+
+  clearHostAddressAndDbErrors() {
+    _.each(['host', 'hostaddr', 'db'], (item) => {
+      this.model.errorModel.unset(item);
+    });
+  }
+
+  checkHostAndHostAddress() {
+    const translatedStr = gettext('Either Host name, Address or Service must ' +
+      'be specified.');
+    if (this.checkForEmpty('host', translatedStr) &&
+      this.checkForEmpty('hostaddr', translatedStr)) {
+      this.errmsg = this.errmsg || translatedStr;
+    } else {
+      this.errmsg = undefined;
+      delete this.err['host'];
+      delete this.err['hostaddr'];
+    }
+
+    this.checkForValidIp(this.model.get('hostaddr'),
+      gettext('Host address must be valid IPv4 or IPv6 address.'));
+  }
+
+  checkForValidIp(ipAddress, msg) {
+    if (ipAddress) {
+      const isIpv6Address = new Address6(ipAddress).isValid();
+      const isIpv4Address = new Address4(ipAddress).isValid();
+      if (!isIpv4Address && !isIpv6Address) {
+        this.err['hostaddr'] = msg;
+        this.errmsg = msg;
+      }
+    } else {
+      this.model.errorModel.unset('hostaddr');
+    }
+  }
+
+  checkForEmpty(id, msg) {
+    const value = this.model.get(id);
+
+    if (ModelValidation.isEmptyString(value)) {
+      this.err[id] = msg;
+      this.errmsg = this.errmsg || msg;
+      return true;
+    } else {
+      this.model.errorModel.unset(id);
+      return false;
+    }
+  }
+
+  static isEmptyString(string) {
+    return _.isUndefined(string) || _.isNull(string) || string.trim() === '';
+  }
+}