Creating new config to set Title of Loklak Webpages

For a Search Engine and Progressive Web Application (PWA) like Loklak, it is important to change the title of each web page with the appropriate query term or configuration of the current active page (A great title can result in higher click-throughs and more traffic to the site, and hence its followed by search engines like Google). For solving this problem, I am writing this blog post which creates a new configuration to change the title dynamically across the whole project by using just one Action thereby maximizing reusability of the code and minimizing duplication.

Create Action for title

We would need to create a new separate title action following the architecture in loklak.

Create a new title.ts file under Actions with the following code:

import { Action } from ‘@ngrx/store’;
export const ActionTypes = {
    SET_TITLE: ‘[Title] SET TITLE’
};
export class SetTitleAction implements Action {
    type = ActionTypes.SET_TITLE;
    constructor (public payload: string) { }
}
export type Actions
    = SetTitleAction;

Create reducer for title

For accessing the current title of the webpage, it is important to create a reducer function for the title following the pattern in loklak.

import * as titleAction from ‘../actions/title’;
export interface State {
	title: string;
}

export const initialState: State = {
	title: '',
};

export function reducer(state: State =
	initialState, action: titleAction.Actions):
	State {
	switch (action.type) {
		case titleAction.ActionTypes.SET_TITLE:
		{
			const titleObt: string =
				action.payload;
			return Object.assign({}, state,
			{
				title: titleObt
			});
		}
		default: {
			return state;
		}
	}
}
export const getTitle =
	(state: State) => state.title;

Create selector and add reducer function to root reducer

The title can be accessed from the current state from store when it would be added to the root state and reducer. Firstly import the title reducer created above and define the title property in root reducer and create a selector for the same.

import * as fromTitle from ‘./title’;
export interface State {
	
	title: fromTitle.State;
}

export const reducers: ActionReducerMap<State> = {
	
	title: fromTitle.reducer
};

export const getTitleState = (state: State) => state.title;

export const getTitle = createSelector(getTitleState,
   fromTitle.getTitle);

Create Effect to change actual title

Now comes the actual part which controls the changing of webpage title using ‘Title’ property of Platform-Browser. Create a new title.effects.ts file under effects using pattern in loklak.

import { Injectable } from ‘@angular/core’;
import { Title } from ‘@angular/platform-browser’;
import { Effect, Actions, ofType }
	from ‘@ngrx/effects’;
import { Observable } from ‘rxjs’;
import { map } from ‘rxjs/operators’;
import * as titleAction from ‘../actions/title’;

@Injectable()
export class SetTitleEffects {

	@Effect({ dispatch: false })
	resetTitle$: Observable<void> = this.actions$
		.pipe(
			ofType(
				titleAction.ActionTypes
					.SET_TITLE
			),
			map((action) => {
			const title =
		action[‘payload’];
			this.titleService
		.setTitle(title);
			})
		);

	constructor(
		private actions$: Actions,
		private titleService: Title
	) { }
}

 

Here the ‘payload’ actually contains the query searched by the user, which will be used update the title.

Note: Before adding a new Effect, the old Effect needs to be removed.

After creating the Effect, add it into app.module.ts and export it in the index.ts.

import {
	
	SetTitleEffects
} from ‘./effects’;

EffectsModule.forRoot([
	
	SetTitleEffects
])

How to set title using this configuration?

Now comes the interesting part. It becomes very easy to set title from any service or component by following the procedure given below.

  • Import the created title action.

import * as titleAction from ‘../actions/title’;

 

  • Set the required title by dispatching the SetTitleAction.
this.store.dispatch(new titleAction
	.SetTitleAction(‘Loklak Search’));

 

You’re all set now! The title has been changed to ‘Loklak Search’ which is what we expect.

Resources

Dispatching a search action to get result for a query in Loklak Search

For a new comer in Loklak, it’s not really easy to understand the complete codebase to just get results for a query without explicitly using navigation route i.e. ‘/search’. In order to help newcomers to easily understand a simple way to get results for a query in the codebase, I am writing this blog post.

Setting up a query

A sample searchQuery will be created of type Query. And following discussion will provide a way to get the results for a sample query – ‘from:Fossasia’ (Last 30 days tweets from FOSSASIA).

searchQuery: Query = {
    displayString: ‘from:FOSSASIA,
    queryString: ‘from:FOSSASIA’,
    routerString: ‘from:FOSSASIA’,
    filter: { video: false, image: false },
    location: null,
    timeBound: { since: null, until: null },
    from: true
}

 

Process discussed here can be used to get results in any class file within Loklak Search.

Using necessary imports

First step would be to add all necessary imports.

import { OnInit } from ‘@angular/core’;
import { Store } from ‘@ngrx/store’;
import { Observable } from ‘rxjs/Observable’;
import * as fromRoot from ‘../../reducers’;
import { Query } from ‘../../models/query’;
import * as searchAction from ‘../../actions/api’;
import { ApiResponseResult } from ‘../../models/api-response’;

 

Note: No need to import OnInit, if the class already implements it (OnInit is one of the Angular’s Lifecycle Hooks which controls the changes when the component containing it gets loaded initially).

The Query is used to define the type of searchQuery variable created above. And ApiResponseResult is the type of result which will be obtained on searching the searchQuery.

Declaring response variables and store object

Next step would be to declare the variables with the type of response and create store object of type Store with the current State of the application.

public isSearching$: Observable<boolean>;
public apiResponseResults$: Observable<ApiResponseResult[]>;
constructor(
    private store: Store<fromRoot.State>
) { }

 

isSearching$ holds an Observable which can be subscribed to get a boolean value which states the current status of searching of query. apiResponseResults$ holds the actual response of query.

Dispatching a SearchAction

The most crucial part comes here to dispatch a SearchAction with the created searchQuery as payload. A new method would be created with void as return type to dispatch the SearchAction.

private queryFromURL(): void {
    this.store.dispatch(
        new searchAction.SearchAction(this.searchQuery)
    );
}

Selecting and storing results from store

A new method would be created to store the current searching status along with the response of input query in isSearching$ and apiResponseResults$ respectively. Now the selector for the reducer function corresponding to the search and api response entities would be called.

private getDataFromStore(): void {
    this.isSearching$ = 
        this.store.select(fromRoot.getSearchLoading);
    this.apiResponseResults$ =   
        this.store.select(
            fromRoot.getApiResponseEntities
    );
}

Dispatching and Selecting on view Init

create ngOnInit() method, If you have not already done and call the respective dispatching and select method inside it respectively.

ngOnInit() {
    this.queryFromURL();
    this.getDataFromStore();
}

How should one test the results?

Call these lines inside any method and look for the results on browser console window.

console.log(this.isSearching$);
console.log(this.apiResponseResults$);

Resources

How to Store Mobile Settings in the Server from SUSI Web Chat Settings Page

While we are adding new features and capabilities to SUSI Web Chat application, we wanted to provide settings changing capability to SUSI users. SUSI team decided to maintain a settings page to give that capability to users.

This is how it’s interface looks like now.

In this blog post I’m going to add another setting category to our setting page. This one is for  saving mobile phone number and dial code in the server.

UI Development:

First we need to  add new category to settings page and it should be invisible when user is not logged in. Anonymous users should not get mobile phone category in settings page.

     let menuItems = cookies.get('loggedIn') ?
            <div>
                <div className="settings-list">
                    <Menu
                        onItemTouchTap={this.loadSettings}
                        selectedMenuItemStyle={blueThemeColor}
                        style={{ width: '100%' }}
                        value={this.state.selectedSetting}
                    >
                       <MenuItem value='Mobile' className="setting-item" leftIcon={<MobileIcon />}>Mobile<ChevronRight className="right-chevron" /></MenuItem>
                        <hr className="break-line" />
                    </Menu>
                </div>
            </div>

 

Next we have to show settings UI when user clicks on the category name.

 if (this.state.selectedSetting === 'Mobile' && cookies.get('loggedIn')) {}
                currentSetting = (
  <Translate text="Country/region : " />
                            <DropDownMenu maxHeight={300}
               value={this.state.countryCode?this.state.countryCode:'US'}

 

Show US if the state does not deines the country code

                                onChange={this.handleCountryChange}>
                                {countries}
                            </DropDownMenu>
<Translate text="Phone number : " />
                            <TextField name="selectedCountry"
                            disabled={true}
                            value={countryData.countries[this.state.countryCode?this.state.countryCode:'US'].countryCallingCodes[0] }
                         	/>
                            <TextField name="serverUrl"
                                onChange={this.handleTelephoneNoChange}
                                value={this.state.phoneNo }
 />
)}

 

Then we need to get list of country names and country dial codes to show in the above drop down. We used country-data node module for that.

To install country-data module use this  command.

npm install --save country-data

 

We have used it in the settings page as below.

import countryData from 'country-data';
    	countryData.countries.all.sort(function(a, b) {
            if(a.name < b.name){ return -1};
            if(a.name > b.name){ return 1};
            return 0;
        });
        let countries = countryData.countries.all.map((country, i) => {
         	return (<MenuItem value={countryData.countries.all[i].alpha2} key={i} primaryText={ countryData.countries.all[i].name+' '+ countryData.countries.all[i].countryCallingCodes[0] } />);
        });

 

First we sort the country data list from it’s name. After that we made a list of “”s from this list of data.
Then we have to check whether the user changed or added the phone number and region (dial code).
It handles by this function mentioned above. ( onChange={this.handleCountryChange}> and
onChange={this.handleTelephoneNoChange} )

    handleCountryChange = (event, index, value) => {
        this.setState({'countryCode': value });
    }

 

Then we have to get the phone number using below function.

    handleTelephoneNoChange = (event, value) => {
        this.setState({'phoneNo': value});
    }

 

Next we have to update the function that triggers when user clicks the save button.

    handleSubmit = () => {
        let newCountryCode = !this.state.countryCode?
        this.intialSettings.countryCode:this.state.countryCode;
        let newCountryDialCode = !this.state.countryDialCode?
        this.intialSettings.countryDialCode:this.state.countryDialCode;
        let newPhoneNo = this.state.phoneNo;
        let vals = {
            countryCode: newCountryCode,
            countryDialCode: newCountryDialCode,
            phoneNo: newPhoneNo
}
let settings = Object.assign({}, vals);
cookies.set('settings', settings);
 this.implementSettings(vals);
 }

 

This code snippet stores Country Code, Country Dial code and phone no in the server.
Now we have to update the Store. Here we are going to change UserPreferencesStore “UserPreferencesStore” .
First we have to setup default values for things we are going to store.

let _defaults = {
	  CountryCode: 'US',
   	  CountryDialCode: '+1',
   	  PhoneNo: ''
}

 

Finally we have to update the dispatchToken to change and get these new data

UserPreferencesStore.dispatchToken = ChatAppDispatcher.register(action => {
   switch (action.type) {
       case ActionTypes.SETTINGS_CHANGED: {
           let settings = action.settings;
           if(settings.hasOwnProperty('theme')){
                   _defaults.Theme = settings.theme;
           }
           if(settings.hasOwnProperty('countryDialCode')){
               _defaults.countryDialCode = settings.countryDialCode;
           }
           if(settings.hasOwnProperty('phoneNo')){
               _defaults.phoneNo = settings.phoneNo;
           }
           if(settings.hasOwnProperty('countryCode')){
               _defaults.countryCode = settings.countryCode;
           }
           UserPreferencesStore.emitChange();
           break;
}
}

 

Finally application is ready to store and update Mobile phone number and region code in the server.

Resources:

Store User’s Personal Information with SUSI

In this blog, I discuss how SUSI.AI stores personal information of it’s users. This personal information is mostly about usernames/links to different websites like LinkedIn, GitHub, Facebook, Google/Gmail etc. To store such details, we have a dedicated API. Endpoint is :

https://api.susi.ai/aaa/storePersonalInfo.json

In this API/Servlet, storing the details and getting the details, both the aspects are covered. At the time of making the API call, user has an option either to ask the server for a list of available store names along with their values or request the server to store the value for a particular store name. If a store name already exists and a client makes a call with new/updated value, The servlet will update the value for that particular store name.

The reason you are looking at minimal user role as USER is quite obvious, i.e. these details correspond to a particular user. Hence neither we want someone writing such information anonymously nor we want this information to be visible to anonymous user until allowed by the user.

In the next steps, we start evaluating the API call made by the client. We look at the combination of the parameters present in the request. If the request is to fetch list of available stores, server first checks if Accounting object even has a JSONObject for “stores” or not. If not found, it sends an error message “No personal information is added yet.” and error code 420. Prior to all these steps, server first generates an accounting object for the user. If found, details are encoded as JSONObject’s parameter. Look at the code below to understand things fairly.

Accounting accounting = DAO.getAccounting(authorization.getIdentity());
        if(post.get("fetchDetails", false)) {
            if(accounting.getJSON().has("stores")){
                JSONObject jsonObject = accounting.getJSON().getJSONObject("stores");
                json.put("stores", jsonObject);
                json.put("accepted", true);
                json.put("message", "details fetched successfully.");
                return new ServiceResponse(json);
            } else {
                throw new APIException(420, "No personal information is added yet.");
            }
        }

If the request was not to fetch the list of available stores, It means client wants server to save a new field or update a previous value for that of a store name. A combination of If-else evaluates whether the call even contains required parameters.

if (post.get(“storeName”, null) == null) {
throw new APIException(422, “Bad store name encountered!”);
}

String storeName = post.get(“storeName”, null);
if (post.get(“value”, null) == null) {
throw new APIException(422, “Bad store name value encountered!”);
}

If request contains all the required data, then store name & value are extracted as key-value pair from the request.

In the next steps, since the server is expected to store list of the store names for a particular user, First the identity is gathered from the already present authorization object in “serviceImpl” method. If the server finds a “null” identity, It throws an error with error code 400 and error message “Specified User Setting not found, ensure you are logged in”.

Else, server first checks if a JSONObject with key “stores” exists or not. If not, It will create an object and will put the key value pair in the new JSONObject. Otherwise it would anyways do so.

Since these details are for a particular account (i.e. for a particular user), these are placed in the Accounting.json file. For better knowledge, Look at the code snippet below.

if (accounting.getJSON().has("stores")) {
                accounting.getJSON().getJSONObject("stores").put(storeName, value);
            } else {
                JSONObject jsonObject = new JSONObject(true);
                jsonObject.put(storeName, value);
                accounting.getJSON().put("stores", jsonObject);
            }

            json.put("accepted", true);
            json.put("message", "You successfully updated your account information!");
            return new ServiceResponse(json);

Additional Resources :

Fixing Infinite Scroll Feature for Susper using Angular

In Susper, we faced a unique problem. Every time the image tab was opened, and the user scrolled through the images, all the other tabs in the search engine, such as All, Videos etc, would stop working. They would continue to display image results as shown:

Since this problem occurred only when the infinite scroll action was called in the image tab, I diagnosed that the problem probably was in the url parameters being set.

The url parameters were set in the onScroll() function as shown:

onScroll () {
let urldata = Object.assign({}, this.searchdata);
this.getPresentPage(1);
this.resultDisplay = ‘images’;
urldata.start = (this.startindex) + urldata.rows;
urldata.fq = ‘url_file_ext_s:(png+OR+jpeg+OR+jpg+OR+gif)’;
urldata.resultDisplay = this.resultDisplay;
urldata.append = true;
urldata.nopagechange = true;
this.store.dispatch(new queryactions.QueryServerAction(urldata));
};

The parameters append and nopagechange were to ensure that the images are displayed in the same page, one after the other.
To solve this bug I first displayed the query call each time a tab is clicked on the web console.
Here I noticed that for the tab videos, nopagechange and append attributes still persisted, and had not been reset. The start offset had not been set to 0 either.
So adding these few lines before making a query call from any tab, would solve the problem.

urldata.start = 0;
urldata.nopagechange = false;
urldata.append = false;

Now the object is displayed as follows:

Now videos are displayed in the videos tab, text in the text tab and so on.
Please refer to results.component.ts for the entire code.

References:

  1. On how to dispatch queries to the store: https://gist.github.com/btroncone/a6e4347326749f938510
  2. Tutorial on the ngrx suite:http://bodiddlie.github.io/ng-2-toh-with-ngrx-suite/

How to Store and Retrieve User Settings from SUSI Server in SUSI iOS

Any user using the SUSI iOS client can set preferences like enabling or disabling the hot word recognition or enabling input from the microphone. These settings need to be stored, in order to be used across all platforms such as web, Android or iOS. Now, in order to store these settings and maintain a synchronization between all the clients, we make use of the SUSI server. The server provides an endpoint to retrieve these settings when the user logs in.

First, we will focus on storing settings on the server followed by retrieving settings from the server. The endpoint to store settings is as follows:

http://api.susi.ai/aaa/changeUserSettings.json?key=key&value=value&access_token=ACCESS_TOKEN

This takes the key value pair for storing a settings and an access token to identify the user as parameters in the GET request. Let’s start by creating the method that takes input the params, calls the API to store settings and returns a status specifying if the executed successfully or not.

 let url = getApiUrl(UserDefaults.standard.object(forKey: ControllerConstants.UserDefaultsKeys.ipAddress) as! String, Methods.UserSettings)

        _ = makeRequest(url, .get, [:], parameters: params, completion: { (results, message) in
            if let _ = message {
                completion(false, ResponseMessages.ServerError)
            } else if let results = results {
                guard let response = results as? [String : AnyObject] else {
                    completion(false, ResponseMessages.ServerError)
                    return
                }
                if let accepted = response[ControllerConstants.accepted] as? Bool, let message = response[Client.UserKeys.Message] as? String {
                    if accepted {
                        completion(true, message)
                        return
                    }
                    completion(false, message)
                    return
                }
            }
        })

Let’s understand this function line by line. First we generate the URL by supplying the server address and the method. Then, we pass the URL and the params in the `makeRequest` method which has a completion handler returning a results object and an error object. Inside the completion handler, check for any error, if it exists mark the request completed with an error else check for the results object to be a dictionary and a key `accepted`, if this key is `true` our request executed successfully and we mark the request to be executed successfully and finally return the method. After making this method, it needs to be called in the view controller, we do so by the following code.

Client.sharedInstance.changeUserSettings(params) { (_, message) in
  DispatchQueue.global().async {
    self.view.makeToast(message)
  }
}

The code above takes input params containing the user token and key-value pair for the setting that needs to be stored. This request runs on a background thread and displays a toast message with the result of the request.

Now that the settings have been stored on the server, we need to retrieve these settings every time the user logs in the app. Below is the endpoint for the same:

http://api.susi.ai/aaa/listUserSettings.json?access_token=ACCESS_TOKEN

This endpoint accepts the user token which is generated when the user logs in which is used to uniquely identify the user and his/her settings are returned. Let’s create the method that would call this endpoint and parse and save the settings data in the iOS app’s User Defaults.

if let _ = message {
  completion(false, ResponseMessages.ServerError)
} else if let results = results {
  guard let response = results as? [String : AnyObject] else {
    completion(false, ResponseMessages.ServerError)
    return
  }
  guard let settings = 
response[ControllerConstants.Settings.settings.lowercased()] as? [String:String] else {
    completion(false, ResponseMessages.ServerError)
    return
  }
  for (key, value) in settings {
    if value.toBool() != nil {
      UserDefaults.standard.set(value.toBool()!, forKey: key)
    } else {
      UserDefaults.standard.set(value, forKey: key)
    }
  }
  completion(true, response[Client.UserKeys.Message] as? String ?? "error")
}

Here, the creation of the URL is same as we created above the only difference being the method passed. We parse the settings key value into a dictionary followed by a loop which loop’s through all the keys and stores the value in the User Defaults for that key. We simply call this method just after user log in as follows:

Client.sharedInstance.fetchUserSettings(params as [String : AnyObject]) { (success, message) in
  DispatchQueue.global().async {
    print("User settings fetch status: \(success) : \(message)")
  }
}

That’s all for this tutorial where we learned how to store and retrieve settings on the SUSI Server.

References