Assume there are two services,
Product Service
Coupon service
Coupon is tagged against the product. And when the coupon is changed for any product there is an API call from product service to the coupon service which calculates the coupon discount and sends back to the product service. And product service maintains that cache. However, To calculate the discount, coupon service need the product information such as product category, SKU type etc. and discount varies based on that so there is again an API call to the product service making it cyclic call. There are a couple of solutions,
maintain product cache at the coupon service. - This is an overhead as we need to maintain the cache on every product field update and this is not the solution we are looking for.
When product service makes an API call to the coupon service, send all the fields it needs - There is tight coupling in this approach.
What is the correct way to solve this problem?
If you have decided that you need 2 different services for this, I would agree that a cyclical dependency is kind of bad and worth trying to remove.
However, I don't really see it being needed here. I think the "coupon" service needs to be aware of the "product" service, but not vice versa.
The issue you are having though is that your coupon service needs to respond to a change that's happening on the product service. Right now you solved this by having the product service send a message to the coupon service.
Some possibilities to fix this include:
Have the coupon service occasionally poll for updates.
Deploy a pub-sub system. Make a 'product change' something you can subscribe to and have the coupon subscribe to that.
I would suggest a third option though. It sounds to me that a 'coupon change' as a concept should not at all exist in the product service. Why does it? It sounds like you actually might have 3 different services:
Product information
Coupon information
Cart
Related
I am looking for a job as a system analyst and in interviews I come across tasks like this.
Imagine that you are working on a credit scoring system that decides whether a user is creditworthy. The user fills an application form and receives notification (say, in SMS) with the scoring result. Apart from the data provided by the user the system utilizes their credit bureau information.
What questions will you ask to clarify the task and what microservices will you propose to create for this system?
It is obvious that the solution I propose is too simple or not enough detailed, so I will be most grateful for the help.
I usually suggest that there will be 4 microsevices:
Service requesting information about the user from the bank database;
Service requesting credit bureau information;
Service performing scoring;
Service sending notifications.
Some questions that come to mind about clarify the task. Would be...
What is the intended use of the credit scoring system? Is it intended to be used by a financial institution to decide whether to grant a loan, or is it intended for some other purpose?
Who will be responsible for maintaining and updating the system? Will there be a dedicated team of developers and analysts working on the system, or will it be the responsibility of a single individual or department?
What data sources will be used to generate the credit scores? Will the system rely solely on information from the user's credit bureau, or will it also incorporate data from other sources, such as bank account information or employment history?
How will the system handle users who do not have a credit bureau file? Will there be a process in place to handle these cases, or will the system simply reject these users?
Based on the information, I came up with the same microservices as you.
A user data service that stores and manages information about users, including their personal and financial information.
A credit scoring service that calculates credit scores based on the data provided by the user and other sources.
A notification service that sends SMS messages to users with their credit scores and any other relevant information.
A data integration service that manages the flow of data between the different microservices and external data sources.
This is just one possible solution, and the specific services involved would be dependent on finding out more information on the business requirements.
I am building some e-commerce functionality into my application, and I only want the client to be able to leave a review for a product if they've bought it. In addition, akin to Amazon, I would also like the front-end "You purchased this item" message to state the date of the purchase as well as its corresponding order ID.
What would be the best way to implement this check on the backend? I am using mongoDB with mongoose and I currently have a User, Product and Order models which may be of use.
Any help is appreciated, thanks! 🙂
I asked this question directly to the Google Analytics community with absolutely no answer.
The question is as follow:
I have a AI based site, which give a customer a specific aid to select the right product he/she want to buy. The front ed application is React/js based.
My site is usually a small icon on a merchant site, and the user, while he/she is navigating the merchant site, can decide to recall clicking on a specific icon.
Then my site opens and help the user to select the right product(s) belonging to the merchant site. The product are choosen and then clicked to be added to the merchant cart.
Of course, there is a written agreement between the merchant and I to be signed, and some changes to the merchant site to incorporate my clickable icon: I'd like to pass a piece of code to the merchant including the icon and all the code needed to implement this kind of application.
So, given that the merchant call my site passing a specific transaction related token and the customer info (if any) when the user click on my icon, how can I:
directly add one or more items into the merchant cart
track the action made by the user after he/she leave me site and return to the merchant one to conclude the journey with a payment, so I can later invoice the merchant for the right commission
track if the user remove some (or all the) item from the cart, so I have less to nothing commissions to invoice.
I tried to follow the instruction given by google, but they are a mess, and I wasn't able to reach any conclusion.
Any help will be really appreciated.
Adding items to the merchant's cart is possible using some live API that the client would extend, but the easiest way to do it would be just using the window.postMessage(). So, I would suggest having your button implemented as a simple iframe. That will make it possible for you to send messages to the parent page from that button. The parent page, however, has to be ready to listen to those messages and add to cart whatever ids you specify. So the client devs will have to do some implementation for this to work.
Well, no, this is a bit too much to ask for. You can ask the merchant to share that data with you so that you could improve your algos (tune them for the client) and, therefore, improve the merchant's conversion rates (which is a win-win scenario), but the merchant would have to actively either implement parallel tracking to your instance of analytics (install your pixel, if you're willing to develop one), or share their own data with you.
That's what a lot of very similar services do. Let's say, Facebook. Facebook sells traffic. When you buy traffic, you generally don't want to pay for irrelevant/badly converting tracking, so you're implementing so-called facebook pixel. Facebook doesn't do this implementation. Client's developers/implementation experts implement it and trigger various events through it, making it send signals to the FB endoint, indicating which client this is from, for which campaign, what the action is page load, purchase, add to cart... Just take a quick glance at FB documentation: https://www.facebook.com/business/help/402791146561655?id=1205376682832142
Facebook is just an example. There are many-many services that do similar pixels. It may be not about selling traffic, it may be about adjusting site look and feel based on AI, or generating discounts and customizing conversion funnels, or even simpler stuff like feedback chat performance and suggestions modules. All these and more exist as third parties and pretty much all of the established ones use pixels for tracking.
If you don't want to spend time at the moment to make your own tracking logic, then implementing a parallel GA tracking will be a pain for you (for your clients, actually). Instead, it would be easier to enrich their data with your products. Let's say, have them implement a product-level custom dimension that would "paint" products added to cart by you and share the data with you.
Note that a client who goes for it must be a very loyal client since analytics data is normally treated as sensitive and is not readily shared with third parties, not mentioning the implementation of a custom dimension (or the using the expensive product parameters) just for a third party to count their conversions. Yes, it has to be a good friend that allows this.
Finally, you could ask them installing your GTM instance or giving you access to theirs, but that would effectively give you the power to execute arbitrary code on any of their page. I would never give a third party that power.
Tl;Dr: I would suggest making your own very simple pixel. Even though it sounds now like a lot of work, it will worth it if the project itself has real potential to be useful for ecommerce.
Exactly the same as 2.
I'm trying to make an app that sells a service, for which users pay based on the amount of time they've used it for, so I don't have a physical shipping address involved.
I want to be able to allow my users to save and then reference saved cards in future transactions. I know the way Stripe tracks a specific customer is through a customer_id, but I'm not sure how to attach a card to a specific customer_id and then reference it in future.
Also, I'm a little confused on the use of ephemeral_keys. Some Stripe tutorials talk about needing these on the server side, and some don't mention them at all, and that leaves me very confused.
This one talks about ephemeral_keys while creating a paymentIntent: https://stripe.com/docs/mobile/ios/basic#
And this one doesn't: https://stripe.com/docs/payments/integration-builder
Any help would be greatly appreciated! Please let me know if you need any more information from me.
PS: If you could also point me to some of the relevant View Controllers Stripe uses to save new cards and display saved cards, I'd be more than grateful!
The flow on https://stripe.com/docs/mobile/ios/basic includes the Customer for your payment context, which will cause the created PaymentMethod to be attached to that Customer. You can verify this after the initial payment by retrieving the PaymentMethod on your backend with your secret key and checking its customer field [0].
If you have a PaymentMethod and want to attach it to a Customer, you'd use the API on the backend [1].
You can retrieve a list of the Customer's existing PaymentMethods via the API [2] on the backed as well (again, with your secret key). Then you can pass a list of their id's and some identifying feature (last 4 digits, as an example) to your app in order to display and let the customer select the one they want to use. Then you take that PaymentMethod's 'id' and use it to create the new payment.
Ephemeral keys are usually only used with the iOS (or Android) SDK's, so when you're using the backend of your integration (i.e. the part that is running on a server somewhere and not distributed with your app) you generally don't need to worry about them.
[0] https://stripe.com/docs/api/payment_methods/retrieve
[1] https://stripe.com/docs/api/payment_methods/attach
[2] https://stripe.com/docs/api/payment_methods/list
I am writing a custom Fiori to access sales data from an SAP ERP backend system using a Gateway.
The use case is "customer logs in launchpad, opens Fiori app and sees all his/hers sales items based on the customer id". The customer id is stored in kna1-kunnr and has to be included in a select on the vbak table in SAP. Nothing fancy.
Now I ask myself: how do I get the customer id / kunnr? What do I get at all from the currently logged in user? When debugging my Gateway project code, is it actually the name stored in sy-uname or can I get something better?
How should I continue to get the customer id / kunnr? Are there some function modules like GET_CUSTOMER_ID_OF_USER to call in the SAP ERP?
Or are the actually other / better ways to get the sales documets for one user?
Update
Thank you for your answers so far. I am going to check the default Fiori implementations to get some inside. But, since we are already here, I want to specify my question a little bit more:
Giving I create an OData model in my Component.js like that:
var oModel = new sap.ui.model.odata.ODataModel("[...]/sap/opu/odata/sap/Z_MYODATA_SRV/",
false, "user", "password" );
user and password are supposed to be the ones currently entered as user credentials in the Fiori Launchpad. How can I access those? Are there some SAPUI5 api like getCurrentUser or getCurrentSession ? Do I actually have to do this user check?
You are correct that to identify all of the sales orders for a customer you need to read them from VBAK (or use BAPI_SALESORDER_GETLIST, etc).
The relationship between logged in user and customer is not something that's the same in every SAP ECC system. You may find that the logged in user is the same as the customer number, but with a prefix - for example, logged in user C12345678 for customer 0012345678. Or there may be some other type of relationship that's store in a custom field on the customer master itself. The best option is to check with the person responsible for the configuration in Sales and Distribution. Only then can you know how to determine the customer for a logged in customer user.
Answering your question
Now I ask myself: how do I get the customer id / kunnr? What do I get at all from the currently logged in user?
It is done on backend with standard customizing, not via OData methods like you intend to do it.
Mikael gave you the rough idea, but didn't finished it so I will give a more comprehensive answer.
We need to differentiate between front-end and back-end authorizations, for Fiori app functioning you need to types of roles/authorizations:
The SAP Fiori roles that define which Fiori apps are displayed to the user
Launchpad authorizations
General OData authorizations
Trusted RFC back-end connectivity authorizations
Back-end authorizations and roles which contain authorizations to display the related business data
This concept is depicted on this figure:
The assignment of the front-end is described here and is out of scope now. Now we are focusing on bullet 2.
Every Fiori app has its role model and one should follow the implementation given in app description. Let's consider how it is done based on Sales Order creation app (F0018) sample:
OData service that returns business-data is SRA017_SALESORDER_CREATE_SRV, so to run it one needs frontend role SAP_SD_BCR_FIELDSALESREP_X1 and backend role SAP_SD_SO_CRE_APP
Also app description give us the following prerequisits:
Before implementing the Create Sales Order app, you must ensure the following:
That an employee master record is created with the following attributes:
If you have implemented SAP ERP HCM and maintained employees in the HCM personnel records, ensure that the employee personnel record has the infotype Communication, with a subtype of System User Name (SY-UNAME) (Infotype 0105, Subtype 0001).
If you have not implemented SAP ERP HCM, implement the Sales and Distribution configuration around Use Sales Employees with HR (Tcode: PULT). This IMG setting copies the appropriate HCM tables from the 000 Client and allows the setup of the employee record with the Infotype Communication and a Subtype of System User Name (SY-UNAME) (Infotype 0105, Subtype 0001).
It associates the USERID of the employee with the personnel number assigned as a partner function sales employee in the customer master.
After implementing the above customer SAP user id will be bound to his employee ID (PERNR), and his employee ID consequently will be bound to partner function in XD02.
And that's not all, what comes next?
THe following order parameters should be maintained in in SIMGH tcode in order customer to see his orders and can create the new ones.
Call transaction SIMGH to open the Create Sales Orders node and configure user information in Customizing activity Define Configuration Parameters using the parameters listed below. For more information, see the documentation available for the Customizing activity.
Document Type (DOCTYPE)
By default, the app uses the standard order document type (technical key TA resp. OR). Changing this to something other than a sales order may significantly impact the functionality of the application.
Order Period (ORDPERIOD)
This defines how many days into the past sales orders are retrieved. The suggested value is 30 days.
Search Period (SEAPERIOD)
This defines how many days into the past a search must look for sales orders that match the search criteria. The suggested value is 90 days.
Ship To Party (SHIP_TO/PARTNER_ROLE)
This defines which partner role in the customer master is used for the ship-to party. The suggested value is WE.
Forwarding Agent (FORWARDING_AGENT/PARTNER_ROLE)
This defines which partner role in the customer master is used for the forwarding agent. The suggested value is SP.
and even that's not all
App description gives the following BADIs to implement in order to enable such linking
Implement the following BAdIs:
Customer Association to Employee
You can use this BAdI to associate employees with specific customers.
Only after all the above steps the customer will be able to order and/or view his sales items.
The moral: always check the app description thoroughly because the role model varies per-app.
Have a look at the standard Fiori applications. For example, in Create Sales Order, there is a BADI provided to implement the relation you are looking for (but for an employee to a customer). In the standard setup, the partner functions of the customer master is used to map what customers are visible to an employee.
Most likely, you have a similar setup already in place if your customers actually have user accounts in your system. If could be as a parameter of the user or as a (custom?) partner role.
http://help.sap.com/saphelp_fiorierpx1_100/helpdata/en/6d/135652f9c21457e10000000a445394/content.htm