Just getting started with Vonk server.
I'm curious to know, under what circumstances do we need to persist FHIR resources in FHIR Server's storage?
You persist the resources in a storage when you want to be able to retrieve and/or use the data later.
It is up to you whether you do that with Vonk as a generic server - i.e. Vonk with its own storage, or with Vonk as a Facade to your back-end storage system. That greatly depends on use case, access to and availability of back-end systems, and design of the architecture, etc.
Related
I started reading microservices architecture and got confused with one below point.
Each service should have a separate database.
Does each service mean a single web(rest) api having its own database?
For example if I take motor insurance claim operation as a business scenario where I modelled business domain services in 3 part Insurance claim services , partner (automobile service providers) services and customer services.
Insurance claim settlement operation in claim api will require other information like incident , survey done by an inspector, policy detail , documents etc.
Now I can create 5 web(rest) api in Insurance claim services and will store its data in common db and other services like partner and customer service will have their own web apis and db
What is correct ?
All web api (claimAPI, PolicyAPI, IncidentAPI, SurveyAPI and DocumentAPI) in claim insurance services should have their own db or they can keep data in single data base ?
Thanks.
To follow microservice best practice, it is correct that they should each have their own database and be exposed solely by APIs. This is because every service in your architecture should be independent and de-coupled from other services. If 2+ services share a database, then there may arise problems in operation or upgrade.
One big issue with a shared database is each service would need to trust that another service doesn't modify it's information. But since they all have access to the same database, one of the others could in fact modify the underlying data and make things unstable or insecure.
Further, with 2+ services relying on a shared database, then you're forced to use the exact same database/version with all. You lose the freedom to independently use MySQL for one and MongoDB for another. Even if the same tool is used for all, when you do maintenance or migration on one you're forced to do it for the rest. All this adds up to some coupled services that make them harder to maintain and scale.
you can have common database for all microservices, it is one of the microservices patterns:
https://microservices.io/patterns/data/shared-database.html
https://docs.aws.amazon.com/prescriptive-guidance/latest/modernization-data-persistence/shared-database.html
check those links to see advantages and disadvantages of this approach.
I have an EMR system its develop using java & oracle database now I want to integrate FHIR server in my system environment and want to share my EMR data to another system. I want to use the HAPI library to integrate FHIR in my system. But I am some confusion about implementation process flow like as different between FHIR client & FHIR server, how to map EMR data to FHIR Resource for mapping data is there any tools? what is the architecture tire? Is FHIR Client and FHIR Server has stayed in the same tire?
A client is a system that invokes operations (search, read, create, update, delete, etc.) on a server. A server is a system that controls data for one or more resources and can respond to operation invocations from an authorized client. If you're using HAPI, you'll need to write code to map between your internal data model and the FHIR objects that will be used to exchange your data with other FHIR systems.
I need quick help regarding Identity server.
There is a client requirement to not allow any public hosted application to directly talk to the database. In Identity server's case, the Identity server will be hosted publicly for token endpoint, and it queries the database for operational data (went for Db approach with reference tokens because IDsrv will be on NLB). Is there any workaround for this? or is this standard practice?
Thanks
If you don't want IdentityServer to talk directly to the database, you will need to implement & register custom implementations of ICorsPolicyService, IAuthorizationCodeStore, IClientStore, IConsentStore, IRefreshTokenStore, IScopeStore, and ITokenHandleStore, that call off to some an external app that can talk to the database.
Normal operating procedure is to have IdentityServer talk directly to the database. I don't see much merit in separating the two.
FYI: You don't need to use reference tokens if you are using load balancing. Check out the deployment docs.
Does Serverless Framework support the ability to deploy the same API to multiple cloud providers (AWS, Azure and IBM) and route requests to each provider based on traditional load balancer methods (i.e. round robin or latency)?
Does Serverless Framework support this function directly?
Does Serverless integrate with global load balancers (e.g. dyn or neustar)?
Does Serverless Framework support the ability to deploy the same API to multiple cloud providers (AWS, Azure and IBM)
Just use 3 different serverless.yml files and deploy each function 3 times.
and route requests to each provider based on traditional load balancer methods (i.e. round robin or latency)?
No, there is no such support for multi-cloud load balancing
The Serverless concept is based on trust: you trust that your Cloud provider will be able to handle your traffic with proper scalability and availability. There is no multi-cloud model, a single Cloud provider must be able to satisfy your needs. To achieve this, they must implement a proper load-balacing schema internally.
If you don't trust on your Cloud provider, you are not thinking in a serverless way. Serverless means that you should not worry about the infra the supports your app.
However, you can implement a sort of multi-cloud load balancing
When you specify a serverless.yml file, you must say which provider (AWS, Azure, IBM) will create those resources. Multi-cloud means that you need one serverless.yml file per each Cloud, but the source code (functions) can be the same. When you deploy the same function to 3 different providers, you will receive 3 different endpoints to access them.
Now, which machine will execute the Load Balance? If you don't trust that a single Cloud provides enough availability, how will you define who will serve the Load Balance feature?
The only solution that I see is to implement this load-balacing in your frontend code. Your app would know the 3 different endpoints and randomize the requests. If one request returns an error, the endpoint would be marked as unhealthy. You could also determine the latency for each endpoint and select a preferred provider. All of this in the client code.
However, don't follow this path. Choose just one provider for production code. The SLA (service level agreement) usually provides a high availability. If it's not enough, you should still stick with just one provider and have in hand some scripts to easily migrate to another cloud in case of a mass outage of your preferred provider.
I have some hardware devices that send some data that need to be stored on the cloud server and also I need to do some real time processing on them.
The data they send need to be preserved for months in some custom binary files. These files related to each device can grow in size up to 10GB over time.
There will client programs (mobile / web) that will be looking at the processed data at real time.
My prefered choice of language is C/C++/C#, since there is time sensitive number crunching involved.
Goal is write scalable application that can have thousands of such devices monitored on the cloud.
Do I have to upfront write the code for running on the cloud ( undestand Azure / amazon EC2) ? Can I write multi threaded desktop application and later migrate to cloud ?
I have used Message passing interface (MPI) in the past for clusters. Can I still use MPI ?
If I use microsoft azure API can I still host my software on Amazon cloud ?
For mobile devices to talk to the server, I understand that I need to have a webservice running. how can I convert a desktop program writeen in C++ / C# to act as a web service talking to client?
Are there any 3rd part frame works or tools taht can help me with my work ?
With most cloud compute services you can deploy an off-the-shelf server and install your own software on it. So, yes, you can write and test you application locally then migrate to the cloud once you get all the bugs worked out. Here are the available EC2 server configurations.
I have not tried MPI but you should be able to run just about anything you want on the servers in the cloud. However, Amazon does offer the Simple Queue Service which provides message passing in the cloud. Your software does not need to run in the cloud to use this service.
I have not used Azure. I doubt there are any restrictions regarding which external servers you use for storage and/or compute. However, keeping your cloud storage and compute resources within a single provider will reduce costs, improve performance and provide you with a unified management interface and billing system.
Web servers are fairly simple things. See this post. That took me about 10 seconds to find.
There is plenty of third party software out there. Figure out what you need in more detail and ask more specific questions