Open Event Server – Export Event as a Pentabarf XML File

FOSSASIA‘s Open Event Server is the REST API backend for the event management platform, Open Event. Here, the event organizers can create their events, add tickets for it and manage all aspects from the schedule to the speakers. Also, once he makes his event public, others can view it and buy tickets if interested.

To make event promotion easier, we also provide the event organizer to export his event as a Pentabarf XML file. Pentabarf XML is used to store events/conferences in a format which most of the scheduling applications can read and add that particular event/conference to the user’s schedule.

Server side – generating the Pentabarf XML file

Here we will be using the pentabarf package for Python for parsing and creating the file.

from pentabarf.Conference import Conference
from pentabarf.Day import Day
from pentabarf.Event import Event
from pentabarf.Person import Person
from pentabarf.Room import Room
  • We define a class PentabarfExporter which has a static method export(event_id).
  • Query the event using the event_id passed and start forming the event in the required format:
event = EventModel.query.get(event_id)
diff = (event.ends_at - event.starts_at)

conference = Conference(title=event.name, start=event.starts_at, end=event.ends_at,
                       days=diff.days if diff.days > 0 else 1,
                       day_change="00:00", timeslot_duration="00:15",
                       venue=event.location_name)
dates = (db.session.query(cast(Session.starts_at, DATE))
        .filter_by(event_id=event_id)
        .filter_by(state='accepted')
        .filter(Session.deleted_at.is_(None))
        .order_by(asc(Session.starts_at)).distinct().all())
  • We have queried for the dates of the event and saved it in dates.
  • We will now iterate over each date and query the microlocations who have a session on that particular date.
for date in dates:
   date = date[0]
   day = Day(date=date)
   microlocation_ids = list(db.session.query(Session.microlocation_id)
                            .filter(func.date(Session.starts_at) == date)
                            .filter_by(state='accepted')
                            .filter(Session.deleted_at.is_(None))
                            .order_by(asc(Session.microlocation_id)).distinct())
  • For each microlocation thus obtained, we will query for accepted sessions to be held at those microlocations.
  • We will also initialize a Room for each microlocation.
for microlocation_id in microlocation_ids:
   microlocation_id = microlocation_id[0]
   microlocation = Microlocation.query.get(microlocation_id)
   sessions = Session.query.filter_by(microlocation_id=microlocation_id) \
       .filter(func.date(Session.starts_at) == date) \
       .filter_by(state='accepted') \
       .filter(Session.deleted_at.is_(None)) \
       .order_by(asc(Session.starts_at)).all()

   room = Room(name=microlocation.name)
  • We will now iterate over the aabove-obtained sessions and instantiate an Event for each session.
  • Then we will iterate over all the speakers of that session and instantiate a Person for each speaker.
  • Finally, we will add that Event to the Room we created earlier.
for session in sessions:

   session_event = Event(id=session.id,
                         date=session.starts_at,
                         start=session.starts_at,
                         duration=str(session.ends_at - session.starts_at) + "00:00",
                         track=session.track.name,
                         abstract=session.short_abstract,
                         title=session.title,
                         type='Talk',
                         description=session.long_abstract,
                         conf_url=url_for('event_detail.display_event_detail_home',
                                          identifier=event.identifier),
                         full_conf_url=url_for('event_detail.display_event_detail_home',
                                               identifier=event.identifier, _external=True),
                         released="True" if event.schedule_published_on else "False")

   for speaker in session.speakers:
       person = Person(id=speaker.id, name=speaker.name)
       session_event.add_person(person)

   room.add_event(session_event)
  • Then we will add the room to the day and then add each day to the conference.
day.add_room(room)
conference.add_day(day)
  • Finally, we will call the generate method of the conference to generate the XML file. This can be directly written to the file.
return conference.generate("Generated by " + get_settings()['app_name'])

Obtaining the Pentabarf XML file:

Firstly, we have an API endpoint which starts the task on the server.

GET - /v1/events/{event_identifier}/export/pentabarf

Here, event_identifier is the unique ID of the event. This endpoint starts a celery task on the server to export the event as a Pentabarf XML file. It returns the task of the URL to get the status of the export task. A sample response is as follows:

{
  "task_url": "/v1/tasks/b7ca7088-876e-4c29-a0ee-b8029a64849a"
}

The user can go to the above-returned URL and check the status of his Celery task. If the task completed successfully he will get the download URL. The endpoint to check the status of the task is:

and the corresponding response from the server –

{
  "result": {
    "download_url": "/v1/events/1/exports/http://localhost/static/media/exports/1/zip/OGpMM0w2RH/event1.zip"
  },
  "state": "SUCCESS"
}

The file can be downloaded from the above-mentioned URL.

Hence, now the event can be added to any scheduling app which recognizes the Pentabarf XML format.

References

Open Event Server – Export Event as xCalendar File

FOSSASIA‘s Open Event Server is the REST API backend for the event management platform, Open Event. Here, the event organizers can create their events, add tickets for it and manage all aspects from the schedule to the speakers. Also, once he makes his event public, others can view it and buy tickets if interested.

To make event promotion easier, we also provide the event organizer to export his event as an xCalendar file. xCal is an XML representation of the iCalendar standard. xCal is not an alternative nor next generation of iCalendar. xCal represents iCalendar components, properties, and parameters as defined in iCalendar. This format was selected to ease its translation back to the iCalendar format using an XSLT transform.

Server side – generating the xCal file

Here we will be using the xml.etree.ElementTree package for Python for parsing and creating XML data.

from xml.etree.ElementTree import Element, SubElement, tostring
  • We define a class XCalExporter which has a static method export(event_id).
  • Query the event using the event_id passed and start forming the calendar:
event = Event.query.get(event_id)

tz = event.timezone or 'UTC'
tz = pytz.timezone(tz)

i_calendar_node = Element('iCalendar')
i_calendar_node.set('xmlns:xCal', 'urn:ietf:params:xml:ns:xcal')
v_calendar_node = SubElement(i_calendar_node, 'vcalendar')
version_node = SubElement(v_calendar_node, 'version')
version_node.text = '2.0'
prod_id_node = SubElement(v_calendar_node, 'prodid')
prod_id_node.text = '-//fossasia//open-event//EN'
cal_desc_node = SubElement(v_calendar_node, 'x-wr-caldesc')
cal_desc_node.text = "Schedule for sessions at " + event.name
cal_name_node = SubElement(v_calendar_node, 'x-wr-calname')
cal_name_node.text = event.name
  • We query for the accepted sessions of the event and store it in sessions
sessions = Session.query \
   .filter_by(event_id=event_id) \
   .filter_by(state='accepted') \
   .filter(Session.deleted_at.is_(None)) \
   .order_by(asc(Session.starts_at)).all()
  • We then iterate through all the sessions in sessions.
  • If it is a valid session, we instantiate a SubElement and store required details
v_event_node = SubElement(v_calendar_node, 'vevent')

method_node = SubElement(v_event_node, 'method')
method_node.text = 'PUBLISH'

uid_node = SubElement(v_event_node, 'uid')
uid_node.text = str(session.id) + "-" + event.identifier

dtstart_node = SubElement(v_event_node, 'dtstart')
dtstart_node.text = tz.localize(session.starts_at).isoformat()

…. So on
  • We then loop through all the speakers in that particular session and add it to the xCal calendar node object as well.
for speaker in session.speakers:
   attendee_node = SubElement(v_event_node, 'attendee')
   attendee_node.text = speaker.name
  • And finally, the string of the calendar node is returned. This is the xCalendar file contents. This can be directly written to a file.
return tostring(i_calendar_node)

Obtaining the xCal file:

Firstly, we have an API endpoint which starts the task on the server.

GET - /v1/events/{event_identifier}/export/xcal

Here, event_identifier is the unique ID of the event. This endpoint starts a celery task on the server to export the event as an xCal file. It returns the URL of the task to get the status of the export task. A sample response is as follows:

{
  "task_url": "/v1/tasks/b7ca7088-876e-4c29-a0ee-b8029a64849a"
}

The user can go to the above-returned URL and check the status of his Celery task. If the task completed successfully he will get the download URL. The endpoint to check the status of the task is:

and the corresponding response from the server –

{
  "result": {
    "download_url": "/v1/events/1/exports/http://localhost/static/media/exports/1/zip/OGpMM0w2RH/event1.zip"
  },
  "state": "SUCCESS"
}

The file can be downloaded from the above mentioned URL.

Hence, now the event can be added to any scheduling app which recognizes the xcs format.

References

Integrating Stripe OAuth in Open Event Frontend

Why is Stripe Oauth needed in frontend? Open event allows organizers to add tickets and accepts payments for tickets through various modes for example, Credit card, Debit card, Netbanking and offline payments. Stripe allows users to accept payments into their linked accounts on various online platforms after they provide client secret and publishable key. So to enable online payments in open event, organizers were required to authenticate their stripe account. This is done through Stripe OAuth.

Flow of OAuth

To allow organizers to link their stripe account admin has to enable stripe under payment gateway in admin settings. Admin provides his client ID and secret key. Admin also sets the redirect URL for his app on the stripe dashboard. After enabling these settings organizer will see an option to link their stripe account to open event when they are creating an event with paid tickets.

Here is what open event frontend does when we click connect to stripe button:

  1. Opens a popup to allow organizer to fill his stripe credentials and authorize open event app to access their secret and publishable key.
  2. Once the organizer fills his credentials and authorizes open event app, open event frontend fetches organizers auth code and saves it to server.
  3. Server on receiving auth code from frontend makes a request to stripe using the auth code to retrieve the publishable key and secret key.
  4. Once these are fetched server saves this information against the event so that all payments for that event can go to the linked stripe account.

Implementing the Frontend portion:

  • Choosing the library:

After looking at various libraries that support OAuth for Ember applications we decided to use Torii. Torii is the library that allows the addition of OAuth for various social apps such as Facebook, Google and Stripe too. It allows writing a custom provider for OAuth in case we do not want to use clients for which torii provides supports by default.

  • Implementing Stripe Provider:

Default provider for stripe given by torii fetched the client ID and redirect URL from environment.js file. But since in open event we have already saved client id of admin in our database so we will extend default stripe provider and modify its client Id so that it fetches client id from server. Code for extending default provider is given here:

import stripeConnect from 'torii/providers/stripe-connect';
import { alias } from '@ember/object/computed';
import { inject } from '@ember/service';
import { configurable } from 'torii/configuration';

function currentUrl() {
 let url = [window.location.protocol,
   '//',
   window.location.host].join('');
 if (url.substr(-1) !== '/') {
   url += '/';
 }
 return url;
}

export default stripeConnect.extend({

 settings: inject(),

 clientId: alias('settings.stripeClientId'),

 redirectUri: configurable('redirectUri', function() {
   return `${currentUrl()}torii/redirect.html`;
 })

});

 

We have fetched clientId from our settings service as alias(‘settings.stripeClientId’).

We have already defined settings in our services so we just need to inject the service here to be able to use it.

By default torii provides redirect url as {currentUrl}/torii/redirect.html. But in open event frontend we allow organizers to edit information on two routes and torii suggests in its docs to use {baseUrl}/torii/redirect.html as the redirect url to avoid potential vulnerability. So we also modified the default redirect url building method.

Saving information to server

Once we get the authorization token from stripe we send it to the server and save it to stripe-authorization model. The logic for the same is given below:

connectStripe() {
     this.get('data.event.stripeAuthorization.content') ? '' : this.set('data.event.stripeAuthorization', this.store.createRecord('stripe-authorization'));
     this.get('torii').open('stripe')
       .then(authorization => {
         this.set('data.event.stripeAuthorization.stripeAuthCode', authorization.authorizationCode);
       })
       .catch(error => {
         this.get('notify').error(this.get('l10n').t(`${error.message}. Please try again`));
       });
   },

 

This action gets called when we click on connect to stripe button. This action calls the stripe provider and opens a popup to enable the organizer to authenticate his stripe account.
Full code for this can be seen here.

In this way we connect the stripe service to open event to allow the organizer to receive payments for his events.

Resources
  • Stripe : Documentation on Stripe-Connect : Link
  • Torii: Library to implement Oauth. : Link
  • Implementation: Link to PR showing its implementation : Link

Open Event Server – Export Event as an iCalendar File

FOSSASIA‘s Open Event Server is the REST API backend for the event management platform, Open Event. Here, the event organizers can create their events, add tickets for it and manage all aspects from the schedule to the speakers. Also, once he makes his event public, others can view it and buy tickets if interested.

To make event promotion easier, we also provide the event organizer to export his event as an iCalendar file. Going by the Wikipedia definition, iCalendar is a computer file format which allows Internet users to send meeting requests and tasks to other Internet users by sharing or sending files in this format through various methods. The files usually have an extension of .ics. With supporting software, such as an email reader or calendar application, recipients of an iCalendar data file can respond to the sender easily or counter propose another meeting date/time. The file format is specified in a proposed internet standard (RFC 5545) for calendar data exchange.

Server side – generating the iCal file

Here we will be using the icalendar package for Python as the file writer.

from icalendar import Calendar, vCalAddress, vText
  • We define a class ICalExporter which has a static method export(event_id).
  • Query the event using the event_id passed and start forming the calendar:
event = EventModel.query.get(event_id)

cal = Calendar()
cal.add('prodid', '-//fossasia//open-event//EN')
cal.add('version', '2.0')
cal.add('x-wr-calname', event.name)
cal.add('x-wr-caldesc', "Schedule for sessions at " + event.name)
  • We query for the accepted sessions of the event and store it in sessions.
sessions = Session.query \
   .filter_by(event_id=event_id) \
   .filter_by(state='accepted') \
   .filter(Session.deleted_at.is_(None)) \
   .order_by(asc(Session.starts_at)).all()
  • We then iterate through all the sessions in sessions.
  • If it is a valid session, we instantiate an icalendar event and store required details.
event_component = icalendar.Event()
event_component.add('summary', session.title)
event_component.add('uid', str(session.id) + "-" + event.identifier)
event_component.add('geo', (event.latitude, event.longitude))
event_component.add('location', session.microlocation.name or '' + " " + event.location_name)
event_component.add('dtstart', tz.localize(session.starts_at))
event_component.add('dtend', tz.localize(session.ends_at))
event_component.add('email', event.email)
event_component.add('description', session.short_abstract)
event_component.add('url', url_for('event_detail.display_event_detail_home',
                                  identifier=event.identifier, _external=True))
  • We then loop through all the speakers in that particular session and add it to the iCal Event object as well.
for speaker in session.speakers:
   # Ref: http://icalendar.readthedocs.io/en/latest/usage.html#file-structure
   # can use speaker.email below but privacy reasons
   attendee = vCalAddress('MAILTO:' + event.email if event.email else '[email protected]')
   attendee.params['cn'] = vText(speaker.name)
   event_component.add('attendee', attendee)
  • This event_component is then added to the cal object that we created in the beginning.
cal.add_component(event_component)
  • And finally, the cal.to_ical() is returned. This is the iCalendar file contents. This can be directly written to a file.
return cal.to_ical()

Obtaining the iCal file:

Firstly, we have an API endpoint which starts the task on the server.

GET - /v1/events/{event_identifier}/export/ical

Here, event_identifier is the unique ID of the event. This endpoint starts a celery task on the server to export the event as an iCal file. It returns the task of the URL to get the status of the export task. A sample response is as follows:

{
  "task_url": "/v1/tasks/b7ca7088-876e-4c29-a0ee-b8029a64849a"
}

The user can go to the above returned URL and check the status of his Celery task. If the task completed successfully he will get the download URL. The endpoint to check the status of the task is:

and the corresponding response from the server –

{
  "result": {
    "download_url": "/v1/events/1/exports/http://localhost/static/media/exports/1/zip/OGpMM0w2RH/event1.zip"
  },
  "state": "SUCCESS"
}

The file can be downloaded from the above mentioned URL.

Hence, now the event can be added to any scheduling app which recognizes the ics format.

References

Open Event Frontend – Implement Access Event API via REST API

FOSSASIA‘s Open Event Frontend uses the Open Event Server as the REST API backend. The user can create an event using the Frontend. He can add sessions, tickets speakers etc. and all this updates the database tables in Open Event Server. The server provides certain endpoints for the user to access and/or update the information. It is important that the user is aware of the expected response from the server for his API request. Let’s see how this is displayed in the frontend.

In the event-view page of the frontend, which is accessible to the organizers, there is an Export tab, along with Overview, Tickets, Scheduler, Sessions, Speakers.

This tab has an Access Event Information via REST API section which displays the URL to be used by the user and the expected response. It looks as follows :

The user can choose between various options which he can include or exclude. The GET URL is modified accordingly and the appropriate response is shown to the user.

Example of this –

How is this implemented in Code?

We maintain two variables baseUrl and displayUrl to display the URL. baseUrl is the URL which is common in all requests, ie, till the include tag.

baseUrl: computed('eventId', function() {
 return `${`${ENV.APP.apiHost}/${ENV.APP.apiNamespace}/events/`}${this.get('eventId')}`;
})

displayUrl is the variable which stores the URL being displayed on the webpage. It is initialized to the same as baseUrl.

displayUrl: computed('eventId', function() {
 return `${`${ENV.APP.apiHost}/${ENV.APP.apiNamespace}/events/`}${this.get('eventId')}`;
})

To store the value of the toggle switches we use toggleSwitches as follows:

toggleSwitches: {
 sessions       : false,
 microlocations : false,
 tracks         : false,
 speakers       : false,
 sponsors       : false,
 tickets        : false
}

Whenever any of the switches are toggled, an action checkBox is called. This method updates the value of toggleSwitches, calls the method to update the displayUrl and make the corresponding API request to update the displayed response. The code looks like this :

makeRequest() {
 this.set('isLoading', true);
 this.get('loader')
   .load(this.get('displayUrl'), { isExternal: true })
   .then(json => {
     json = JSON.stringify(json, null, 2);
     this.set('json', htmlSafe(syntaxHighlight(json)));
   })
   .catch(() => {
     this.get('notify').error(this.get('l10n').t('Could not fetch from the server'));
     this.set('json', 'Could not fetch from the server');
   })
   .finally(() => {
     this.set('isLoading', false);
   });
},

buildDisplayUrl() {
 let newUrl = this.get('baseUrl');
 const include = [];

 for (const key in this.get('toggleSwitches')) {
   if (this.get('toggleSwitches').hasOwnProperty(key)) {
     this.get('toggleSwitches')[key] && include.push(key);
   }
 }

 this.set('displayUrl', buildUrl(newUrl, {
   include: include.length > 0 ? include : undefined
 }, true));
},

actions: {
 checkboxChange(data) {
   this.set(`toggleSwitches.${data}`, !this.get(`toggleSwitches.${data}`));
   this.buildDisplayUrl();
   this.makeRequest();
 }
}

The above code uses some utility methods such as buildUrl and this.get(‘loager’).load(). The complete codebase is available here -> Open Event Frontend Repository.

References

SUSI AI 5 Star Skill Rating System

For making a system more reliable and robust, continuous evaluation is quite important. So is in case of SUSI AI. User feedback is important to improve SUSI skills and create new ones. Previously we had only thumbs up / thumbs down as a feedback method, from the susi chat client. But now a 5 star rating system has been added to the SUSI Skill CMS so that users can rate a skill there. Before the implementation of API  let’s look how data is stored in SUSI AI Susi_server uses DAO in which skill rating is stored as JSONTray.

The server side implementation

A new java class has been created for the API, FiveStarRateSkillService.java.

public class FiveStarRateSkillService extends AbstractAPIHandler implements APIHandler {
    private static final long serialVersionUID =7947060716231250102L;
    @Override
    public BaseUserRole getMinimalBaseUserRole() {
        return BaseUserRole.USER;
    }
    @Override
    public JSONObject getDefaultPermissions(BaseUserRole baseUserRole) {
        return null;
    }
    @Override
    public String getAPIPath() {
        return "/cms/rateSkill.json";
    }
...
}

The getMinimalBaseRole method tells the minimum User role required to access this servlet it can also be ADMIN, USER or ANONYMOUS. In our case it is USER. A user needs to be logged in to rate a skill on a scale of 1-5 stars.  The API runs at “/cms/fiveStarRateSkill.json” endpoint.

Next, create serviceImpl method in the above class to handle the request from the client and respond to it.

  1. Fetch the required query parameters and store them in variables. They include skill model, group, language, skill name and starts that the user has given in the rating.

String skill_name = call.get("skill", null);
String skill_stars = call.get("stars", null);
  1. Then check if the skill exists. If not them throw an exception. Otherwise, increment the count of the corresponding rating. The rating object has keys as one_star, two_star, three_star, four_star and five_star that has the count of that star rating.       

if (skill_stars.equals("1")) {
    skillName.put("one_star", skillName.getInt("one_star") + 1 + "");
}
else if (skill_stars.equals("2")) {
    skillName.put("two_star", skillName.getInt("two_star") + 1 + "");
}
else if (skill_stars.equals("3")) {
    skillName.put("three_star", skillName.getInt("three_star") + 1 + "");
}
else if (skill_stars.equals("4")) {
    skillName.put("four_star", skillName.getInt("four_star") + 1 + "");
}
else if (skill_stars.equals("5")) {
    skillName.put("five_star", skillName.getInt("five_star") + 1 + "");
}
  1. Re-calculate the total rating done on that skill and its average rating and update the object. If the skill has not been already rated then create a new rating object and initialize it with the 0 star counts.

public JSONObject createRatingObject(String skill_stars) {
        JSONObject skillName = new JSONObject();
        JSONObject skillStars = new JSONObject();

        skillStars.put("one_star", 0);
        skillStars.put("two_star", 0);
        skillStars.put("three_star", 0);
        skillStars.put("four_star", 0);
        skillStars.put("five_star", 0);
        skillStars.put("avg_star", 0);
        skillStars.put("total_star", 0);

        skillName.put("stars", skillStars);
}

The complete FiveStarRateSkillService.java is available here : –

https://github.com/fossasia/susi_server/blob/development/src/ai/susi/server/api/cms/FiveStarRateSkillService.java

Rating a skill

Sample endpoint

https://api.susi.ai/cms/fiveStarRateSkill.json?model=general&group=Knowledge&language=en&skill=aboutsusi&stars=3&callback=p&_=1526813916145

This gives 3 star rating to the “aboutsusi” skill.

Parameters

  • Model
  • Group
  • Language
  • Skill
  • Stars

Response

{
  "ratings": {
    "one_star": 0,
    "four_star": 0,
    "five_star": 1,
    "total_star": 1,
    "three_star": 0,
    "avg_star": 5,
    "two_star": 0
  },
  "session": {"identity": {
    "type": "email",
    "name": "[email protected]",
    "anonymous": false
  }},
  "accepted": true,
  "message": "Skill ratings updated"
}

Getting the stats of Skill Ratings

Sample endpoint

http://127.0.0.1:4000/cms/getSkillRating.json?model=general&group=Knowledge&language=en&skill=aboutsusi&callback=p&_=1526813916145

This fetches the current ratings of the “aboutsusi” skill.

Parameters

  • Model
  • Group
  • Language
  • Skill

Response

{
    "session": {
        "identity": {
            "type": "host",
            "name": "172.68.144.159_81c88a10",
            "anonymous": true
        }
    },
    "skill_name": "aboutsusi",
    "accepted": true,
    "message": "Skill ratings fetched",
    "skill_rating": {
        "negative": "0",
        "positive": "0",
        "stars": {
            "one_star": 0,
            "four_star": 2,
            "five_star": 1,
            "total_star": 4,
            "three_star": 1,
            "avg_star": 4,
            "two_star": 0
        },
        "feedback_count": 3
    }
}

Conclusion

So this 5 star rating system will help in improving the SUSI skills. Also, it will help in making better decisions when we have multiple similar skills and we have to choose one to respond to the user query.

References

Adding “All” in Skill Categories

The SUSI SKill CMS has various filters to explore the skills of interest.  For example skill category and skill language. The skills are stored in the susi_skill_data Github repo in the following structure:

susi_skill_data/models/<model_name>/<group_name>/<language_name>/<skill_name>.txt

NOTE: group and category are same terms and can be used interchangeably

So when a category filter is applied the skills from the corresponding directory are returned.

susi_skill_data/models/<model_name>/<group_name>/<language_name>/<skill_name>.txt

But there’s no directory called “All”,  so how to get skills of all groups? For this, we need to loop through all the directories present in the model.

Server side implementation

Create a helper function that returns a list of all the folders present in a directory. The function accepts the parent directory name and an empty list. First, fetch all the items (files and folders) present in that directory and store them in an array. Then apply a filter over the array to check if the element is a directory and doesn’t start with a dot(.) i.e., it’s not hidden. Add the filtered array to the list.

private void listFoldersForFolder(final File folder, ArrayList<String> fileList) {
    File[] filesInFolder = folder.listFiles();
    if (filesInFolder != null) {
        Arrays.stream(filesInFolder)
                .filter(fileEntry -> fileEntry.isDirectory() && !fileEntry.getName().startsWith("."))
                .forEach(fileEntry -> fileList.add(fileEntry.getName() + ""));
    }
}

Fetch the group name form the request and add a check if the CMS is asking for all skill. Otherwise, return the skills of a particular group only.

String group_name = call.get("group", "Knowledge");
if (group_name.equals("All")) {
  // Return the list of all skills
} else {
  // Return the list of a skills in a particular group only
}

To fetch the list of all skills, call the listFoldersForFolders() function with the model name and an empty list as arguments. The function adds all the directories, present in that model directory, to folderList.

File allGroup = new File(String.valueOf(model));
ArrayList<String> folderList = new ArrayList<String>();
listFoldersForFolder(allGroup, folderList);

Then loop over all the groups present in the list to get all the skills present in that group. This process is the same as the existing process of getting skills of a particular category. Just keep adding the skill list to a global array.

CMS side implementation

The list of categories is first fetched from the API and then added to the dropdown menu. Since the API doesn’t return “All” in it, so we need to push it to the list manually.

groups.push(<MenuItem
                value="All"
                key="All"
                primaryText="All" />);

References

Adding System Image for Event Categories

The Open Event Server is using the JSON 1.0 Specification and build on top of Flask Rest Json API (for building Rest APIs) and Marshmallow (for Schema). In this blog, we will talk about how to add feature of System Image for Event Categories on Open Event Server. The focus is on Model updation, Schema updation and migrating the Database.

Model Updation

For adding System Image, we’ll update our Model EventTopic.

In this feature, we are providing rights to the Admin to add a system image for each Event Category so that if no image is given by a organizer of event on event creation then it will use the system image of that Event Category as event image by default.

Here we are adding a Column named system_image_url which is of type String. This value cannot be nullable and having a default value.

Migrating the Database

For the migrating the Database we will use simple commands.

This command runs migrations. If it cause problems naming Multiple Migration Head, then you need to run

This problem is caused when two developers push a migration file without merging two heads to achieve one head.

The above command will give us ids of two migration heads.

This command is merging two migration heads.

This command is upgrading the migrations.

Finally, we migrate the Database using above command.

Schema Updation

For the system image, we’ll update the Schema EventTopicSchema as follows

In this feature, to provide system image for each Event Category we’ll add a field named system_image_url in the Schema.

Here we are adding a field named system_image_url which is of marshmallow field type URL. This value cannot be none.

Validating the Event Image and using System Image by default

In this step, we’ll check if a event image is provided by organizer. If that is not provided then we’ll use system image of Event Category as Event Image.

Here, we will first take the event topic of event as added by the organizer. Then we will fetch the the database row in Event Topic model which has id == event_topic_id . Then we will return the system image url of that event topic to the event image.

So we saw how we could provide a default image for any event.

Resources

Adding Event Roles concerning a User on Open Event Server

The Open Event Server enables organizers to manage events from concerts to conferences and meetups. It offers features for events with several tracks and venues. Event managers can create invitation forms for speakers and build schedules in a drag and drop interface. The event information is stored in a database. The system provides API endpoints to fetch the data, and to modify and update it. The Open Event Server is based on JSON 1.0 Specification and hence build on top of Flask Rest Json API (for building Rest APIs) and Marshmallow (for Schema).

In this blog, we will talk about how to add different events role concerning a user on Open Event Server. The focus is on its model and Schema updation.

Model Updation

For the User Table, we’ll update our User Model as follows:

Now, let’s try to understand these hybrid properties.

In this feature, we are providing Admin the rights to see whether a user is acting as a organizer, co-organizer, track_organizer, moderator, attendee and registrar of any of the event or not. Here, _is_role method is used to check whether an user plays a event role like organizer, co-organizer, track_organizer, moderator, attendee and registrar or not. This is done by querying the record from UserEventsRole model. If the record is present then the returned value is True otherwise False.

Schema Updation

For the User Model, we’ll update our Schema as follows

Now, let’s try to understand this Schema.

Since all the properties will return either True or false so these all properties are set to Boolean in Schema. Here dump_only means, we will return this property in the Schema.

So, we saw how User Model and Schema is updated to show events role concerning a user on Open Event Server.

Resources