(Micro) Services dependencies and relations documentation - web-services

When you have so many services, let's say more than 50 services and you want to know the relation between services, for instance you want to know which services have hard dependency on each other and which have soft dependency on each other, meaning when a service goes down and doesn't function anymore which other services will not work.
Basically for providing a level of High availability and uptime (SLA) we also need this.
and also when a new person joins the team there should be some kind of documentation to see what services we have and how is the dependency tree.
what kind of relation they have ? just messaging through a message broker or direct requests ?
Are those services working in just test environment or prod environment ? or both ?
What tools and softwares are there to help us cover this.

I am just now also looking into this question. Especially modelling dependencies between services.
In my opinion you can go into two directions
Service Registry
Configuration Management DB
There are a lot of full blown Service Registries out there, which do are not only static documentation, but services als register themselves with the service registry and others can discover the service to user there automatically.
Eureka related to Netflix Open Source Stack (Netflix OSS)
Consul
Zookeeper
Etcd
For me the Service Registry option might be to complex and I am going into the the direction of a simple CMBD

Related

SaaS Multitenant Architecture

i just arrived on this architecture, am doing a lot of research and i understood how it work in general but it's all theorical.
I decided to separate each step for the development of this architecture to start implementing so i can understand better these steps.
The first that i wanted to learn was the tenant provisioning, i wanted to apply it on AWS to mirror a production software example.
So, starting on that the common AWS service that i see most people using is AWS Cognito, but it's not clear in my mind the steps of the implementation, like how should i get the tenant data to onboard him in my app? Assuming it's tier based.
Should i have one database to store all tenants data separate from the application database?
I want to use microservices on this one because i think is better to onboard the tenant with different tiers and much more benefits.
Which AWS services should i use to make this process work? I'm not really asking about the implementation itself but a path to understand which services to use and how it connects with each other.
I hope i was clear about my doubts, english is not my mother tongue, sorry about that!
You are thinking in the right direction. However, there are decisions you need to make before diving into any saas service stack. I would start with
Planning my infrastructure - how many tenants/group.
the kind of tenant onboarding system you want
How will tenants onboard their users and manage authorization/authentication
Multitenant architecture, which needs to account for several things at the least like - DB model, shared vs isolated, data privacy, design keeping in mind industry data security standards
what will be your tenant deployment model. Remember one of the disadvantages of multitenancy is also slow time to market.
Your API stack needs to account for which apis needs to be multitenant and which are generic product offerings.
operational tool to monitor app health, client analytics.
how will you meter and bill the client and other non-functional decisions.
AWS offers good documentation to get started here : https://aws.amazon.com/blogs/apn/building-a-multi-tenant-saas-solution-using-aws-serverless-services/

Devops project management board in Google Cloud platform

Does the Google Cloud platform has the project management board like azure DevOps. If so please someone can provide the details
Right now there is no such thing in GCP. There are other tools but nothing related to Project Management. I think becuase in general terms, this would not add much to what GCP offers:
Platform as a service (PaaS).
Functions as a service (FaaS).
Containers as a service (CaaS).
Infrastructure as a service (IaaS).
Storage Services, Databases.
BigData services, Machine Learning Services.
Anyway, if you have a general idea of how you would like to work and which products you think it could interact with, you can file a Feature Request on the Public Issue Tracker with as much as details as possible.
I found this post named Google Project Management Doesn’t Exist… Now What? which you might find interesting.
I also found this about G Suite tips for project management. The most relevant could be:
Create dynamic project plans and Gantt charts in Sheets to manage your projects, assignments, and deadlines. Team members across the globe can update their progress directly in the spreadsheet so it's always up to date.

Microservices service registry registration and discovery

Little domain presentation
I m actually having two microservices :
User - managing CRUD on users
Billings - managing CRUD on billings, with a "reference" on a user concerned by the billing
Explanation
I need, when a billing is called in a HTTP request, to send the fully billing object with the user loaded. In that case, and in this specifical case, I really need this.
In a first time, I looked around, and it seems that it was a good idea to use message queuing, for asynchronicity, and so the billing service can send on a queue :
"who's the user with the id 123456 ? I need to load it"
So my two services could exchange, without really knowing each other, or without knowing the "location" of each other.
Problems
My first question is, what is the aim of using a service registry in that case ? The message queuing is able to give us the information without knowing anything at all concerning the user service location no ?
When do we need to use a service registration :
In the case of Aggregator Pattern, with RESTFul API, we can navigate through hateoas links. In the case of Proxy pattern maybe ? When the microservices are interfaced by another service ?
Admitting now, that we use proxy pattern, with a "frontal service". In this case, it's okay for me to use a service registration. But it means that the front send service know the name of the userService and the billing service in the service registration ? Example :
Service User registers as "UserServiceOfHell:http://80.80.80.80/v1/"
on ZooKeeper
Service Billing registers as "BillingService:http://90.90.90.90/v4.3/"
The front end service needs to send some requests to the user and billing service, it implies that it needs to know that the user service is "UserServiceOfHell". Is this defined at the beginning of the project ?
Last question, can we use multiple microservices patterns in one microservices architecture or is this a bad practice ?
NB : Everything I ask is based on http://blog.arungupta.me/microservice-design-patterns/
A lot of good questions!
First of all, I want to answer your last question - multiple patterns are ok when you know what you're doing. It's fine to mix asynchronous queues, HTTP calls and even binary RPC - it depends on consistency, availability and performance requirements. Sometimes you can see a good fit for simple PubSub and sometimes you need to have distributed lock - microservices are different.
Your example is simple: two microservices need to exchange some information. You chose asynchronous queue - fine, in this case they don't really need to know about each other. Queues don't expect any discovery between consumers.
But we need service discovery in other cases! For example, backing services: databases, caches and actually queues as well. Without service discovery you probably hardcoded the URL to your queue, but if it goes down you have nothing. You need to have high availability - cluster of nodes replicating your queue, for example. When you add a new node or existing node crashed - you should not change anything, service discovery tool should understand that and update the registry.
Consul is a perfect modern service discovery tool, you can just use custom DNS name for accessing your backing services and Consul will perform constant health checks and keep your cluster healthy.
The same rule can be applied to microservices - when you have a cluster running service A and you need to access it from service B without any queues (for example, for HTTP call) you have to use service discovery to be sure that endpoint you use will bring you to the healthy node. So it's a perfect fit for Aggregator or Proxy patterns from the article you mentioned.
Probably the most confusion is caused by the fact that you see "hardcoded" URLs in Zookeeper. And you think that you need to manage that manually. Modern tools like Consul or etcd allows you to avoid that headache and just rely on them. It's actually also achievable with Zookeeper, but it'll require more time and resources to have similar setup.
PS: please remember about the most important rule in microservices - http://martinfowler.com/bliki/MonolithFirst.html

WSO2 / Mule vs OpenStack / CloudStack - what are the differences, similarities, benefits?

I've started my journey with cloud related technologies very recently. I'm trying to understand the basics as to be able to prepare the foundation for a basic cloud setup in my Internet of Things oriented company.
While browsing the Internet I've stumbled upon the following two groups of open source projects:
WSO2 / Mule / ...
OpenStack / CouldStack / Eucalyptus / ...
I'm trying to understand:
what kind of service do they offer? (IaaS, PaaS, SaaS, other?)
what are the differences between them?
what do they have in common?
how do the play with other cloud related technologies like Amazon AWS?
which one would you recommend to get some basic experience and for some early proof-of-concept? (I'm looking for the easiest option first)
Cloud stack and Open stack are open source softwares designed to manage, deploy virtual machines and networks which can deliver cloud services. Mainly these provide Infrastructure as a Service (IaaS). There are alot of comparisons on the internet on these two. So these softwares needs to be intalled on your hardware and maintain it and you provide a cloud service from it. When it comes Amazon AWS it is a readily available service where you don't do installations or maintain hardware, you just take service from them.
WSO2 and MuleSoft are different from above two and they are software platforms where several products(such as ESB). Both provide cloud platform facilities to deploye their products.
We cannot say which one to use but base on your requirements you may choose one or two (WSO2 products deployed on Amazon AWS or WSO2 products deployed on CloudStack VM's). Since you are willing to set up Internet of things, i think you may need to refer about products provided by above providers. Following source [1] will give you an idea about Iot platform setup by several free open source WSO2 products.
[1] http://wso2.com/landing/internet-of-things/

Identifying ASP.NET web service references

At my day job we have load balanced web servers which talk to load balanced app servers via web services (and lately WCF). At any given time, we have 4-6 different teams that have the ability to add new web sites or services or consume existing services. We probably have about 20-30 different web applications and corresponding services.
Unfortunately, given that we have no centralized control over this due to competing priorities, org structures, project timelines, financial buckets, etc., it is quite a mess. We have a variety of services that are reused, but a bunch that are specific to a front-end.
Ideally we would have better control over this situation, and we are trying to get control over it, but that is taking a while. One thing we would like to do is find out more about what all of the inter-relationships between web sites and the app servers.
I have used Reflector to find dependencies among assemblies, but would like to be able to see the traffic patterns between services.
What are the options for trying to map out web service relationships? For the most part, we are mainly talking about internal services (web to app, app to app, batch to app, etc.). Off the top of my head, I can think of two ways to approach it:
Analyze assemblies for any web references. The drawback here is that not everything is a web reference and I'm not sure how WCF connections are listed. However, this would at least be a start for finding 80% of the connections. Does anyone know of any tools that can do that analysis? Like I said, I've used Reflector for assembly references but can't find anything for web references.
Possibly tap into IIS and passively monitor the traffic coming in and out and somehow figure out what is being called and where from. We are looking at enterprise tools that could help but it would be a while before they are implemented (and cost a lot). But is there anything out there that could help out quickly and cheaply? One tool in particular (AmberPoint) can tap into IIS on the servers and monitor inbound and outbound traffic, adds a little special sauce and begin to build a map of the traffic. Very nice, but costs a bundle.
I know, I know, how the heck did you get into this mess in the first place? Beats me, just trying to help us get control of it and get out of it.
Thanks,
Matt
The easiest way is to look through the logs, but if that doesn't include the referrer than you may also want to monitor what is going out from your web to the app server. You can use tools like Wireshark or Microsoft Network Monitor to see this traffic.
The other "solution" and I use this loosely is to bind a specific web server to app server and then run through a bundle and see what it is hitting on the app server. You could probably do this in a test environment to lesson the effects on the users of the site.
You need a service registry (UDDI??)... If you had a means to catalog these services and their consumers, it would make this job of dependency discovery a lot easier. That is not an easy solution, though. It takes time and documentation to get a catalog in place.
I think the quickest solution would be to query your IIS logs and find source URLs which originate from your own servers. You would at least be able to track down which servers your consumers are coming from.
Also, if you already have some kind of authentication mechanism in place, you could trace who is using a particular service based on login.
You are right about AmberPoint. There are other tools that catalog the service traffic and provide reports showing what is happening to your services. Systinet, SOA Software and Actional also has a products similar to Amberpoint but Amberpoint has a free-ware version, I believe.