Developing Dapp in Hyperledger Fabric - hyperledger-fabric

I'm trying to develop a Dapp using Hyperledger Fabric on Mac. However, I can't find any recent tutorials online in developing a Dapp in Hyperledger Fabric. In setting up the development environment, I tried following Fabric's official documentation but I struggled through it and encountered a lot of errors. Can you suggest documentations or tutorials for developing Dapp in Hyperledger Fabric?

The fabcar example (APIs and chaincode) is very basic and good to start with. It has few APIs to interact with the chaincode. All you have to do is create a frontend and connect these APIs with the frontend.
One more example is this.

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Where to start with Hyperledger Fabric Development?

I am pretty new to Hyperledger fabric and try to understand what all topics I need to learn so that I am able to create one full application.
Like for Ethereum , I followed below steps.
1. Setup Ethereum development environment.
2. Used the solidity language to develop the smart contract and used remix as beginner to create smart contract.
3. Use of Truffle Framework for development, testing etc.
4. deploy the smart contract to blockchain either from remix or using truffle framework.
5. Use Web3 to access that smart contract function deployed on blockchain from front end.
Please help me with me similar steps for Hyperledger Fabric.
I heard about lot of terms like composer, modeling language, ACL, Scripts files under that. I also heard about Go language and SDK there.
My understanding is that, first of all Hyperledger Fabric need to be setup on the local system that I am able to do and next step is do the development of DAPP.
One option to that development is by using Hyperledger composer but I dont see use of Go language there. So I wanted to know if composer if the only option to do the development or we have any other way.
Hyperledger Composer is a tool, that simplifies application development on top of the Hyperledger Fabric blockchain infrastructure.
If you are interested in the blockchain infrastructure, start with the Fabric tutorials.
If you are interested in blockchain applications, start with the Composer tutorials.
The Fabric tutorials includes the development in to way:
You can use either Go language to write chain code or you can use composer language.
You can try both.
There is also Fabric Java SDK available for building Java client applications that interact with the blockchain.
I advise you at first to deploy a first hyperledger network in localhost (use docker-compose). You can help yourself with the fabric-sample https://github.com/hyperledger/fabric-samples.
You must understand the mechanisms of transactions (proposal, endorsement etc.) the roles of each component.
After that learning to deploy a chaincode, learn the development of GO chaincodes linked to hyperledger fabric.
Then you can approach the hyperledger SDK (NodeJS or Java).
Start with Hyperledger Composer, its a hyperledger fabric building tool: (https://hyperledger.github.io/composer/latest/introduction/introduction.html)
Composer allows you to experiment and play around with Hyperledger Fabric Blockchain through an online web interface. No need to jump into core building blocks when using Composer. The language used is mostly javascript / yml based so its easy to pick up.
Next step is to work directly with Hyperledger Fabric. But by the time you would have gone through Composer that will be your decision.
About the languages used, Hyperledger Fabric blockchain can be setup using GO, Node or Java.
as a start you can try hyperledger composer which is tool made to accelerate the implementation of your blockchain application smart contracts, ACL to your participant so to understand whats going on pleas follow the documentation in the following link
and you will find this online composer playground very helpful to get your hands on implementation and test your application flow then you can export your application file as .bna file and deploy it on your hyperledger fabric framework.
after that you have to install the prerequisites for hyperledger localy which you can find in the following link
after that you have to decide the type of fabric your going to use will it be single organization fabric which will use solo messaging server to handle synchronization between order peer and your peer.However, you can use multi organization fabric to be your framework which rely upon kafka and zookeeper to manage state between your multi orders and deploy your application.However, you can find node fabric SDK to manage your hyperledger fabric.

Has anyone tried Service Discovery, with Hyperledger Composer "fabric-dev-servers"?

Using BYFN I was able to fetch the Anchor Peers using Discovery Services.
Now I am trying use the same for Hyperledger Composer "fabric-dev-servers" network but getting null.
Has anyone tried it and can provide the changes that might be needed?
Thanks in Advance!
The fabric-dev-servers package is meant as a simple development fabric so that developers using composer can get up and running with a real fabric.
If you need discovery then it would make sense to stick with BYFN as the fabric you want to develop against, or to look at the various hyperledger fabric resources and build a fabric to your requirements.

do I need to use fabric sdk if am using hyperledger composer

I am using hyperledger composer for transaction invocation and all the stuffs related to resource(participants, assets etc) manipulation. I have generated the server using composer-rest-server, and also generated the angular frontend using yeoman generator.
This makes me to ask what is the use of fabric sdk? Will I need it in the above mentioned scenario?
Please clarify, thanks.
There are two ways to write chaincode in Hyperledger Fabric,
1) Using GoLang
2) Using NodeJS
In order to connect Hyperledger Fabric and Invoke chaincode transaction. You will require SDK. Based on your application technology stack, You can either use Fabric NodeJS SDK, Fabric Java SDK and Fabric Python SDK.
On other hand; Hyperledger composer is different way of writing chaincode, which is guide of framework which can help you to accelerate your chaincode development. If you have developed business network using composer, then you can either use "composer rest server" or "composer-admin" and "composer-client" node module. You dont need to use any SDK in order to interact with Business network deployed on hyperledger fabric. Kindly refer following diagram for more clarity.

If I have existing nodejs web app how can i configure it with hyperledger?

As hyperledger is an enterprise blockchain solution so it does not make any sense to create a complete application from scratch, are there any resources available to explore integrating hyperledger with existing applications(specifically MEAN application)?
There are two options for integrating Hyperledger Fabric with the MEAN stack:
1) The Fabric Node SDK: https://fabric-sdk-node.github.io
2) If the Hyperledger Fabric smart contracts are built with Hyperledger Composer, Composer generates a REST API which can then be easily integrated with existing MEAN applications

creating business network in composer to fabric

If we can build a business network in composer playground online(or) locally and then deploy network in fabric, make a REST call from an angular app (user facing) to connect to blockchain.
Do I still need to learn about the fabric implementation or its infrastructure, When composer has provided me with necessary toolings to work with blockchain.
What am I missing in this ?
ps:I am still in the early phase of learning hyperledger and so not very clear as to use which and when.
Composer just provide necessary tools to work with blockchain.
But if you want to build your own blockchain network, You need to learn about fabric.
In composer guide, it mainly showed two fabric networks: One organization Hyperledger Fabric and Two organizations Hyperledger Fabric.
Let's say if you want to add one more organization or add one more peer node for each organization. You can't implement the requirements just utilize composer.
I'm also quite new to this. So if I understand well your answer lissdy, if I follow the developer tutorial (https://hyperledger.github.io/composer/tutorials/developer-tutorial.html) my network will be deployed but with only one peer ? And I need to use fabric to go further ?

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