How can we handle Callback URL redirection in FD serverless app?

App Platform
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21

Hi Saif, we checked with third party team and they have said that they are following RFC 6749 protocol and authorization code in grant type.

22

@rohan15 Thank you for patiently working through this problem.

I strongly feel it would help if we see a brief description of the problem you are trying to solve. Perhaps what you are trying to do is not the right way to achieve it on our platform. We can help you choose the right solution and then work toward solving issues with implementing the same.

Could you please describe in brief what you are actually trying to do in this app? Feel free to leave out details that might be business-specific - but we would want to understand what the app needs to do in terms of acting on events and what kind of authentication is expected by the endpoints you are hitting.

23

Hi Satwik, what we are trying to do is build an FD serverless app which calls a SMS sending API which requires Oauth2 authentication to be accessed. The process is given below:

  1. On ticket creation event, FD serverless app to make a call to authorization API and be redirected to a callbackurl with authorization code.
  2. Take authorization code and make a call to Token Generation URL.
  3. Use this token and call the actual API for sending SMS.

As suggested by Saif, we have made use of FD’s platform feature for using Oauth2:

  1. We have registered the callbackURL as http://localhost:10001/auth/callback on the third party’s portal.
  2. We have created a serverless app and have created oauth_config.json file in the app’s config/ folder.
  3. We have whitelisted the API endpoint in Manifest File.
  4. We have run fdk run on command prompt.
  5. We have invoked the SMS sending API from server.js file by using $request.post.

The issue we are facing now, is that in requets_token we are not getting the value of the token.code in our server.js file. Some of the error screenshots can be screen if you see the previous posts.

We are getting null in the token in FD app. Therefore, we have scheduled a call with Saif tomorrow to debug this issue, as we had discussed this usecase with him previously on the portal.

Basically we want to know if any additional configuration/code has to be written for getting the token?

1 Like
24

Hi Saif, Raghu,

Thanks a lot for your time. We will check with our team regarding the payload and confirm to you guys on the developer forum on what we plan to do.
One more thing, I wanted to confirm with you. Suppose we manage to get the token in access_token variable, your FD platform itself will re-use the same token until it gets expired and then generate a new one from token url?
If not, any feature on FD for this as well? The thirdparty token is valid for around 1 hour. After that a new one is required to be generated…so can this also be handled in the FD app platform through some configuration?

25

Yes, @rohan15.

Platform it self will refresh the access_token with the help of referesh token.

26

Summary for this thread followers

Rohan is trying to implement a OAuth mechanism with a 3rd OAuth service. On the way he discovered that he doesn’t have to implement OAuth exchange himself but freshworks platform provides OAuth 2 capabilities.

  • However, upon following to leverage this feature, Rohan found that platform is not able to fetch access_token sent by 3rd party provider.
  • We got on a call and found out that the payload being sent by the 3rd party has property naming it accessToken instead of access_token as per official standard response structure.

Rohan is trying to find a workaround to solve this problem. One of the options to consider is to use a Middleware that can translate to the standard response structure for our platform begin OAuth cycle.

2 Likes
27

Hi Saif/Team,

With reference to our last post, the third party is trying to we will provide a new oAuth endpoint with below request/response.

Could you please help to confirm the same today, so that we can ask them to go ahead?

{
“status”: “approved”,
“access_token”: “Cd0Vh5g44IuRqBGdrrOh0”,
“refresh_token”: “muFpsulLCzAB4HyfnYwAIfroN”,
“expires_in”: “2399”,
“scope”: “”,
“token_type”: “BearerToken”
}

Request will be same like before:
POST /oauth/v1/token HTTP/1.1
Content-Type: application/x-www-form-urlencoded
Cache-Control: no-cache
grant_type=authorization_code&client_id=SpxYtZAMgUfD1XjTmHmZ1yzZf91xuKp8&client_secret=NyzsTWj5lHXctxwz&code=xhFSO5kM

28

The structure adheres to RFC standards. This should be fine @rohan15.

29

Hi Saif/Team,

The third party had deployed the Oauth endpoint with the RFC protocol standards. We tested it and our serverless app is now able to do the Oauth2 authentication and get the access_token for calling the SMS API.
Could you please help to clarify the below 3 points as well:

  1. Yesterday night we had initiated the request and access_token was generated. Today when we hit the request for the first time, we got “Token Expired” from third party. It was only after we deleted the .fdk file , the access_token got replaced. Will we need to delete .fdk folder everytime in FD test environment? When we deploy in FD production , how will this run ? Will it be handled automatically or manual intervention be required? As per the last document shared, the authorization_code from url redirection is for 1 time use only.

  2. Secondly, after token is being substituted, and Third Party API is being called, the SMS is being sent as expected by third party. Third party is returning JSON response body as well , however what we can understand from below logs is that at FD side it’s being treated as an error response because it can’t find “Application/json” (A capital). Any workaround for this at FD side to show it as SUCCESS?

    FDK 3468: (proxy.js) Proxy came back with error as null, body as {“id”:“631021001”,“type”:“TEXT”,“status”:“SUCCESS”,“sentTime”:“2020-05-15T12:55:56+06
    :30”,“content”:
    FDK 3468: (proxy.js) Looking for “Application/json” in application/json,application/xml,text/html,text/xml,application/jsonp,text/plain,application/ja
    vascript,application/vnd.api+json
    error { status: 415,
    headers: {},
    response: ‘Unsupported content type’,
    errorSource: ‘APP’,
    attempts: 1 }
    FDK 3468: (coverage-util.js) Writing coverage.

  3. Do you have any concept in FD serverless app for an external property file that can be updated on runtime? Basically we would like to keep the SMS texts in a property file such that the text can be changed whenever required without redeploying the application.

30

Hi Saif, Team,

Would like to add 1 more question in addition to the above 3:
Currently this servless app is being invoked onTicket creation event only. If we want this single serverless app to be invoked onTicketCreation, onTicketClose and onTicketUpdate events how would we need to modify our server.js so that it can be invoked on all 3 events. Could you please provide some samples for the same?

31

Hello @rohan15,

  1. Yes, for the app in production the exchange of token is automatically handled by the platform itself.
  2. Since you functionality of app: sending SMS is being achieved, does this error message obstruct you from the your app running in any way? Meanwhile, I will find out if there’s any thing that we can do on our end.
  3. Did you get a chance to checkout out External events feature? What you are trying to achieve is seems to be a bit close to it.
32

Hi Saif/Team,

Please find below comments:

  1. Therefore, it means , in TND, we will basically need to delete the .fdk folder everytime the token has expired right, as token referesh didn’t happen here? In production this will be handled automatically.
  2. Yes, please help to check if the error message could be resolved. Functionality is being achieved but it would be great if we could get this marked as SUCCESS in the logs.
  3. Just wanted to confirm, if we want the serverless app to be invoked on both onTicketCreation and onTicketClose, is External events feature the recommended way or can we add this event somehow directly in our server.js? Could you explain briefly how we can add these 2 events-ticket create and ticket close in the same app such that for onticketcreate FUNCTION 1 is called and for onTicetClose FUNCTION2 is called in the same app?
    4.Also could you please suggest regarding the below as well:
    Do you have any concept in FD serverless app for an external property file that can be updated on runtime? Basically we would like to keep the SMS texts in a property file such that the text can be changed whenever required without redeploying the application.
33

You can do same function declaration and definition out the exports block and make a function call inside the any product event that you want. I hope that should help you solve the problem.

34
  1. Yes. Incase, the access token expires, the CLI will automatically, try to refresh using refresh tokens. In the production this mechanism is handled automatically.
  2. I will get in touch with some of our platform engineers find help and keep you posted.
  3. In your case, if you want same functionality to be triggered, please follow this method.
  4. External events feature actually gets you a webhook. Where required functionality will get executed which is defined under onExternalEventHandler is triggered. What you can do, is to send a POST req to the generated webhook URL with the message and can leverage iparams functionatlity to set the required message to send SMS.
35

Thanks Saif/Team.

We will check the above information and try to implement the same.

Could you guys also let us know that in the PAYLOAD for onTicketCreation and OnTicketClose, which parameters do we refer to for getting the ticket id number ,ticket creation date and expected resolution date? Actually, we need to send this information in our SMS.

36

Hi Team,

Please help to provide the above details regarding ticket details from onTicketCreate and onTicketClose payload. Thanks

37

Kindly refer to the developer docs for payload reference -> Freshdesk Product Events

38

Thanks Hemchander for the information.

Hi Saif/Team,

Could you please check with platform engineers today on the below point and let us know the update?
If they could include the header mentioned?

39

Yes, I’ve checked with the team. Unfortunately, we won’t be able to makes changes on our platform. The solution goes as discussed before to write a middleware or changes within 3rd party response following RFC standards.

40

Ok Saif, we will need to discuss with our team once regarding this.

Need some more info:

  1. Is there any utility in FD which can convert string text to UTF-16 Hexa String (unicode). We are able to send English texts in SMS but for sending SMS in English and Burmese languages, we need to convert it to unicode. Here ticketid will be passed dyanmically in the SMS. Please suggest if there is any feature we can use.
  2. Also, we would now have to gradually deploy this in FD production. Could you guys please share the related links for:
    a.) Deployment on production.
    b.) Removing and adding another version of the build.
    c.) Authorizing app on production. In testing environment, we were able to find the authorize button on test console. Where would we find this option in production