I am having trouble understanding how to use a microservices model. The idea of a microservice is that I have multiple local servers, each serving a different port. Connecting to these local servers can be easily done locally (e.g., using an Express hosted website). But if I am using a frontend application, such as React, how am I supposed to call the different APIs.
The only solution I can seem to think is to create a subdomain per API, but this seems far-fetched and impractical since I would need to create a lot of entries inside the Names Server (e.g., Cloudflare).
If I am using an application like Apache or Nginx, is there a way to publicly access the APIs using a single domain? Or using subsubdomains such as api1.subdomain.domain.com, api2.subdomain.domain.com ... but without adding each of these subdomains to the name server?
An alternative I can think of is creating a public API whose job is to connect to local services, but this seems to defeat the purpose of microservices.
I can't find anything online and all tutorials always use localhost which does not work in production code.
Thanks in advance!
You should research API Gateways / Edge-Services.
Personally, I like hosting the containers for microservices in Kubernetes and forwarding all traffic to *.mydomain.tld to the kubernetes cluster and configuring the load balancing (in this case: which subdomain should be routed to which service) there.
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I'm trying to get a proof of concept going for a multi-tenancy containerized ASP.NET MVC application in Service Fabric. The idea is that each customer would get 1+ instances of the application spread across the cluster. One thing I'm having trouble getting mapped out is routing.
Each app would be partitioned similar to this SO answer. The plan so far is to have an external load balancer route each request to the SF Reverse Proxy service.
So for instance:
tenant1.myapp.com would get routed to the reverse proxy at <SF cluster node>:19081/myapp/tenant1 (19081 is the default port for SF Reverse Proxy), tenant2.myapp.com -> <SF Cluster Node>:19081/myapp/tenant2, etc and then the proxy would route it to the correct node:port where an instance of the application is listening.
Since each application has to be mapped to a different port, the plan is for SF to dynamically assign a port on creation of each app. This doesn't seem entirely scaleable since we could theoretically hit a port limit (~65k).
My questions then are, is this a valid/suggested approach? Are there better approaches? Are there things I'm missing/overlooking? I'm new to SF so any help/insight would be appreciated!
I don't think the Ephemeral Port Limit will be an issue for you, is likely that you will consume all server resources (CPU + Memory) even before you consume half of these ports.
To do what you need is possible, but it will require you to create a script or an application that will be responsible to create and manage configuration for the service instances deployed.
I would not use the built-in reverse proxy, it is very limited and for what you want will just add extra configuration with no benefit.
At moment I see traefik as the most suitable solution. Traefik enables you to route specific domains to specific services, and it is exactly what you want.
Because you will use multiple domains, it will require a dynamic configuration that is not provided out of the box, this is why I suggested you to create a separate application to deploy these instances. A very high level steps would be:
You define your service with the traefik default rules as shown here
From your application manager, you deploy a new named service of this service for the new tenant
After the instance is deployed you configure it to listen in a specific domain, setting the rule traefik.frontend.rule=Host:tenant1.myapp.com to the correct tenant name
You might have to add some extra configurations, but this will lead you to the right path.
Regarding the cluster architecture, you could do it in many ways, for starting, I would recommend you keep it simple, one FrontEnd node type containing the traefik services and another BackEnd node type for your services, from there you can decide how to plan the cluster properly, there is already many SO answers on how to define the cluster.
Please see more info on the following links:
https://blog.techfabric.io/using-traefik-reverse-proxy-for-securing-microservices-on-azure-service-fabric/
https://docs.traefik.io/configuration/backends/servicefabric/
Assuming you don't need an instance on every node, you can have up to (nodecount * 65K) services, which would make it scalable again.
Have a look at Azure API management and Traefik, which have some SF integration options. This works a lot nicer than the limited built-in reverse proxy. For example, they offer routing rules.
Maybe this is a really basic question, but how do you architect your system such that your single page application is hosted on premise with some hostname, say mydogs.com but you want to host your application services code in the cloud (as well as database). For example, let's say you spin up an Amazon EC2 Container Service using docker and it is running NodeJS server. The hostnames will all have ec2_some_id.amazon.com. What system sits in from of the Amazon EC2 instance where my angularjs app connects to? What architecture facilitate this type of app? Especially AWS based services.
One of the important aspects setting up the web application and the backend is to server it using a single domain avoiding cross origin requests (CORS). To do this, you can use AWS CloudFront as a proxy, where the routing happens based on URL paths.
For example, you can point the root domain to index.html while /api/* requests to the backend endpoint running in EC2. Sample diagram of the architecture is shown below.
Also its important for your angular application to have full url paths. One of the challenges having these are, for routes such as /home /about and etc., it will reload a page from the backend for that particular path. Since its a single page application you won't be having server pages for /home and /about & etc. This is where you can setup error pages in CloudFront so that, all the not found routes also can be forwarded to the index.html (Which serves the AngularJS app).
The only thing you need to care about is the CORS on whatever server you use to host your backend in AWS.
More Doc on CORS:
https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS
Hope it helps.
A good approach is to have two separated instances. It is, an instance to serve your API (Application Program Interface) and another one to serve your SPA (Single Page Application).
For the API server you may want more robust service because it's the one that will suffer the most receiving tons of requests from all client instances, so this one needs to have more performance, band, etc. In addition, you probably want your API server to be scalable when needed (depends on the load over it); maybe not, but is something to keep in mind if your application is supposed to grow fast. So you may invest a little bit more on this one.
The SPA server in the other hand, is the one that will only serve static resources (if you're not using server side rendering), so this one is supposed to be cheaper (if not free). Furthermore, all it does is to serve the application resources once and the application actually runs on client and most files will end up being cached by the browser. So you don't need to invest much on this one.
Anyhow, you question about which service will fit better for this type of application can't be answered because it doesn't define much about that you may find the one that sits for the requisites you want in terms of how your application will be consumed by the clients like: how many requests, downloads, or storage your app needs.
Amazon EC2 instance types
For an angular app that completely relies on external API to retrieve and store data, is NodeJS necessary for deployment? What are the other possible methods of deployment? Currently, I use it for local development and plan on using it in combination with Nginx for production. However, NodeJS is not doing anything except launching index.html. So should I remove NodeJS altogether and simply use Nginx alone?
One solution is to host it using any web host, they all equally host HTML only sites, and this solution is pretty inexpensive. Hosts like Hostgator, web.com etc., will allow you to upload the site via FTP.
A second choice is to host it using a web server (Nginx), but this is probably the most costly. You can host your own server in any cloud service (Amazon would be EC2 for instance) and then host your files there. This is probably not a good option for you. The only reason to use this type of solution is if you need the server to host code, so if you were using node to talk to a database for instance.
A 'pro' option may be to put them in S3 on AWS, and host it that way, it is pretty inexpensive.
Here is a link explaining how to host on Amazon - http://docs.aws.amazon.com/AmazonS3/latest/dev/WebsiteHosting.html
http://docs.aws.amazon.com/AmazonS3/latest/dev/website-hosting-custom-domain-walkthrough.html
We're developing a cloud based web application for customer management. One of the main goals i the capability to connect to different local applications on the customer endpoint.
As example, we don't want to have a customer database in out application, the customer should be able to search within his local ERP system right away.
What we need is not much. Only a client on the customers server with access to the local SQL server as well as the COM model.
But as webdevelopers and mainly going with PHP the question came up, what technology we should use?
I've got two approaches in mind:
NodeJS
Lightweight, Javascript and with the Express and winole32 extension we should have everything we need. But the deployment and installation as a service seems to be a bit wacky.
C# .Net Web API
Also a good approach I guess since the client servers are allways windows. But is there a way without IIS?
Or do you have something completely different in mind? It should be very fast and compact. So its basically just a RESTservice that can be deployed with ease.
Thanks for your inputs and thoughts.
C# .Net Web API Also a good approach I guess since the client servers are
allways windows. But is there a way without IIS
It is called OWIN and it is properly documented (web api self host is a good keyword) and works like a charm. Using that on various services to expose an API into the service.
Is it possible to create a google app engine program that would route http requests to a server on a local network?
What would be the best way to build a program like this?
I am trying to get away from buying a server from a hosting provider and simply use a local network server instead, and use google apps as a sort of proxy. The firewall would be configured to allow access to the server from the google app engine servers only.
If this has been done before in an open source project that would be excellent, but I have not been able to find one.
If all you want is a domain name that points to your dynamic IP address, you could give Dynamic DNS a try. It's designed for your use case, and you won't need to write any code; you just need either a router that supports it or a server with cron. There are lots of providers, but I've had good experiences with Dyn DNS, specifically their Remote Access plan.