Can a private Cardano network be created? - cardano

In Ethereum we can use geth to create a private network, for example by defining a genesis block with puppeth and then creating nodes.
Is there an equivalent of geth in Cardano and can we create private networks?

Don't know much about Ethereum but to set up private network for cardano you need "Cardano-sl". Do set it up on your local or VPS according to this instruction https://github.com/input-output-hk/cardano-sl/blob/develop/docs/how-to/build-cardano-sl-and-daedalus-from-source-code.md . After downloading and building binaries from either nix or stack mode you need to connect your node to mainnet or testnet as per your requirement follow this link for the same: https://github.com/input-output-hk/cardano-sl/blob/develop/docs/how-to/connect-to-cluster.md .
Now your node should start downloading blocks and it will take some time to complete sync. you can check synchronization progress by using simple curl command: curl -X GET https://localhost:8090/api/v1/node-info: also you need to provide certs with the request or can call with insecure option by proving -k option with the request, see API reference for complete info: https://cardanodocs.com/technical/wallet/api/v1/#
And once your node will be in sync, you can call APIs and create your wallet, accounts and do ADA transactions.
Although, I skipped some steps but i hope still it will help many to get going.

Related

Not able to deploy solana smart contract over devnet

I have followed below steps to deploy my smart contract over solana devnet but i am facing Blockhashed Expired: 5 retries remaining .
I have followed below steps to deploy my smart contract over solana devnet but i am facing Blockhashed Expired: 5 retries remaining .
solana-keygen new --outfile solana/my_wallet.json --force
solana config set --url devnet
solana airdrop 2 0xxx .... 0xxxx [and get sufficient balance upto 10 sol]
anchor build
solana address -k target/deploy/my-keypair.json
Copy programId and updated my Anchor.toml file as well as Lib.rs file [declare_id]
Set cluster and programs to devnet in Anchor.toml file
anchor build
I updated programId in idl file as well.
anchor deploy --provider.cluster devnet
How to resolve this issue?
this might be one issue
solana address -k target/deploy/my-keypair.json
file name should include your contract name. this is the syntax
yourContractName-keypair.json
you should also add this to anchor.toml
cluster = "devnet"
wallet = "./my_wallet.json"
It looks like you're using the Public RPC. One possible cause of this issue is that the public devnet RPC is overloaded.
You might want to try a private RPC. You can try using a service like Quicknode, which has private Solana devnet RPCs and a free tier you can use for this purpose.
Then, once you have the URL to your private node, you use:
solana config set --url https://quicknode.com.....{insertrestofurl}

Getting Started With PeerJS

I am trying the simplest example I can, pulled directly from their website. Here is my entire html file, with code taken exactly from https://peerjs.com/index.html:
<script src="https://unpkg.com/peerjs#1.3.1/dist/peerjs.min.js"></script>
<script>
var peer = new Peer();
var conn = peer.connect('another-peers-id');
// on open will be launch when you successfully connect to PeerServer
conn.on('open', function(){
// here you have conn.id
conn.send('hi!');
});
</script>
In Chrome and Edge I get this in the console:
peerjs.min.js:64 GET https://0.peerjs.com/peerjs/id?ts=15956160926060.016464029424720694 net::ERR_CONNECTION_REFUSED
In Firefox I get this:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://0.peerjs.com/peerjs/id?ts=15956162489620.8436734374800061. (Reason: CORS request did not succeed).
What am I doing wrong?
#reyad has requested "a full trace of requests and responses". Here's what I see in my network tab in Firefox:
And here's Chrome:
And a tiny bit more Chrome:
[Note: It would have been better if you could provide a full trace of requests and responses. This problem may occur for several reasons. I'll state two solutions. So, try those. If those doesn't work, provide full trace of requests and responses.]
1. First Solution:
Sometimes, this type of error occurs because of self-signed certificate. To solve this problem, open developer tools/options, then go to network tab. You'll see a list of requests. Select the request which was failed because of CORS(i.e. which gave you this Reason: CORS request did not succeed). Open it(i.e. click it). If your problem is related to cert you'll see the following error message:
AN ERROR OCCURED: SEC_ERROR_INADEQUATE_KEY_USAGE
To solve this problem, go to url that is the reason of this problem and accept the certificate manually.
2. Second solution:
Check the request(which is the reason of CORS) in the network tab of developers tools/options(same as described in 1. First Solution). You'll find a Transferred column. See, what's written in the Transferred column of the failed request. If it is written Blocked By Some Ad-Blocker, then disable the Ad-Blocker. Your request will work fine.
[P.S.]: These solutions are proposed on assumptions. Hope these works. If these two do not work, then please provide more info about requests and responses. And also check this.
3. Third and final solution:
[Note: This solution may not solve your problem directly, but it'll give you alternative solution and also insight about what your problem is and how to work around it]
Before reading the solution below, read this to understand how Access-Control-Allow-Origin works(it is the reason for CORS error).
Let me first explain how peerjs works:
PEERJS works based on PEER ID. So, you've to get some PEER ID either from the PEERJS CLOUD SERVER or you've to provide yourself one in the PEER CONSTRUCTOR i.e. new Peer("some-peer-id"). Peer id has to be unique, cause its necessary to detect all the users uniquely. And, peerjs uses this PEER ID to send and receive data from user to user.
Now, you should know that, you're using PEERJS CLOUD SERVER to get/generate unique peer id which is the default server PEERJS uses unless you specified some other server to use.
Now let me explain why you're facing this problem:
As you already know how CORS works, you may have already guessed, that https://unpkg.com/peerjs#1.3.1/dist/peerjs.min.js(the downloaded js file) is calling https://0.peerjs.com to retrieve/generate new unique PEER ID. But, this request by https://your.website.com does not have Access-Control-Allow-Origin access for some reason, it may also be a middleware problem. So, its difficult to tell where the problem is actually occuring. But one thing for sure, it's not your fault of writing code :D.
I hope all the concepts is clear to you I've stated above.
Now, to solutions:
Alternative-appraoch-1 (Using PEERJS CLOUD SERVER AND Your own provided id):
In this approach you've to generate your own unique PEER ID. So, "https://your.website.com" does not have to call "https://0.peerjs.com" for unique peer id. [Note: make your peer id large enough so that its always unique, at least 64 chars long]
In this way, you can avoid the CORS problem.
Update:
I just saw an new issue in github, which says the public peerjs cloud server is now unstable or does not work properly. It just gives error like: Firefox cannot establish a connection with the server at the address wss://0.peerjs.com/peerjs?key=peerjs&id=123222589562487856955685485555&token=ocyxworx62i and in Chrome: Error in connection establishment: net::ERR_CONNECTION_REFUSED. For details check here. So, its better, you use your own server(see the next approach).
Alternative-appraoch-2 (Using your own peerjs server):
You can host your own peerjs server instead of PEERJS CLOUD SERVER. In this way, you can allow access to anyone/any website you want. If you want know how to host a peerjs server, you may visit here.
[P.S.]: I have studied pearjs issues in github. After reading all those issues, it seems, it is better to use your own server rather than using pearjs cloud. There are a lot of various problems with each new release of peerjs. And mostly related with connection with peerjs cloud and also peerjs cloud is not stable I guess. They were hosting it in 0.peerjs.com:9000 before(not secure). But now in 0.peerjs.com:443.
I haven't use peerjs before nor set up peerjs server. If you want to set up one, I hope the community would be able help you on how to do that properly.
What I understand from your question is that there is an issue of (CORS => Cross-origin resource sharing ), Maybe what I am suggesting is not very intuitive.
First : download the "https://unpkg.com/peerjs#1.3.1/dist/peerjs.min.js" in your local directory . and then incklude the local javascript code to the html.
like: <script src="./peerjs.min.js"></script>
Second :
you are using var peer = new Peer();
but please provide an extra unique id from your side. for example, I just created a random id and provided it.
StackOverflow link: https://stackoverflow.com/questions/21216758/peerjs-set-your-own-peerid#:~:text=1%20Answer&text=Provide%20a%20peer%20id%20when,to%20under%20Create%20a%20peer.
var a_random_id = Math.random().toString(36).replace(/[^a-z]+/g, '').substr(2, 10);
var peer = new Peer(a_random_id, {key: 'myapikey'});
Third : the best option is to run PeerServer: A server for PeerJS of your own.
If you don't want to develop anything, just enter a few commands below.
Install the package globally:
$ npm install peer -g
Run the server:
$ peerjs --port 9000 --key peerjs --path /myapp
Started PeerServer on ::, port: 9000, path: /myapp (v. 0.3.2)
Check it: http://127.0.0.1:9000/myapp It should return JSON with name, description, and website fields.
details:https://github.com/peers/peerjs-server

Hyperledger Fabric CA - Storing the identity materials the correct way

Currently I have a VM running and installed the binaries needed for fabric-ca. I have a docker-compose file looking like this:
I have some questions regarding this:
the docker-compose file will create one container, if I want it for
more organizations, do I need to copy/paste this and change the port
number? (I don't want to use intermediate CAs).
When registering/enrolling an identity, it will override the default
materials because It will always put the materials from the new identity in /etc/hyperledger/fabric-ca-client. So when creating multiple
identities (orderer, peers, users etc..) how do I need to organize
them? What's the best practise?
In the image you can see that the server and clients are specified,
is this a good approach? Or should the client and the server be a
different container?
More than one CA in a Docker Compose file - you can look at the Build your first network tutorial in the Fabric Docs which has a 2 Org network and various configuration files including Docker Compose.
Combined client/server Container - This might be convenient for testing, but in a production scenario definitely not for Security and Operational Integrity reasons.
Overwriting Identities - the enroll command writes a tree of data to the location specified by the environment variable FABRIC_CA_CLIENT_HOME but you can use --home to redirect the tree to a different location:
fabric-ca-client enroll -u http://Jane:janepw#myca.example.com:7054 --home /home/test/Jane/

Google Vision API - tatusCode.RESOURCE_EXHAUSTED

I am new to the Google Vision API and I would like to conduct a label detection of approx. 10 images and I would like to run the vision quickstart.py file. However when I do this with only 3 images then it is successful. With more than 3 images I am getting the error message below. I know that I would need to change something at my setup, but I do not know what I should change.
Here is my error message:
google.gax.errors.RetryError: GaxError(Exception occurred in retry method
that was not classified as transient, caused by <_Rendezvous of RPC that
terminated with (StatusCode.RESOURCE_EXHAUSTED, Insufficient tokens for
quota 'DefaultGroup' and limit 'USER-100s' of service
'vision.googleapis.com' for consumer 'project_number: XXX'.)>)
Does anybody know what I need to do?
Any help would be much appreciated
Cheers,
Andi
I ran into the same problem and fixed it with these steps:
Make sure you have the Google Cloud SDK properly installed: https://cloud.google.com/vision/docs/reference/libraries
Setup a Service Account in the Google Cloud backend: https://developers.google.com/identity/protocols/OAuth2ServiceAccount#creatinganaccount
Create a Service Account Key and download it as a JSON file to a local folder. You need to keep the key private.
Export the filepath to the key-file as an environment variable: gcloud auth activate-service-account --key-file path/to/your/keyfile/here
Log out/in of the console.
Make sure, the environment variable is properly set with printenv
Try your py-script again...
Good luck...
Edit: In addition to the mentioned steps 1.-3. you can just do vision_client = vision.Client.from_service_account_json('/path/to/your/keyfile.json') in your script. No need for the env variable then.

Trouble adding a new service

I have followed the instructions at https://github.com/cloudfoundry/oss-docs/tree/master/vcap/adding_a_system_service and copied the echo service and created my new service. (That document is somewhat out-of-date in that "excluded components" no longer exists.
In any case, my service shows up as running with a gateway and a node when I look at 'vcap status' on the server. However, when I look at 'vmc services' from the client my service is not in the list. Where is this list maintained and why is my service not on the list?
Various services, including blob, filesystem, mongodb, etc, are shown on the 'vcm services' list even though they have never been included in my config. Where is this maintained and why are other services on this list?
The cloud_controller.log file shows a "Create service request:" for echo every minute. This service is not in my config file (it was once but it was removed and I repeated the deployment). What is prompting this request for a service that was not defined in the config?
The _gateway.log for my service shows the following:
INFO -- Sending info to cloud controller: ...api.vcap.me/services/v1/offerings
INFO -- Fetching handles from cloud controller .../offerings/.../handles
ERROR -- Failed registering with cloud controller, status=400
DEBUG -- [GaaS-Provisioner] Connected to node mbus..
ERROR -- Failed fetching handles, status=404
Why does my gateway fail to register with the cloud controller? I have found some reports that suggest that the problem is with domain name mapping. I have verified that the server can find itself:
$curl api.vcap.me
Welcome to VMware's Cloud Application Platform
What can I do to register my service?
You can also try asking your question on the vcap_dev google group.
https://groups.google.com/a/cloudfoundry.org/forum/?fromgroups#!forum/vcap-dev
They are focused in answering and discussing OSS subjects for Cloud Foundry!
If you follow the document correctly things should work just fine. I understand that the mechanism for maintaining the excluded list of components has changed and can be a point of confusion when following the steps mentioned in the article (just ignore that step totally).
ERROR -- Failed registering with cloud controller, status=400
Well this is a point of worry. I recently followed the article step by step and was able to add a new service.
Is the echo service showing up in vmc services?
Have you copied the the yml files for node and gateway at ./cloudfoundry/.deployments/devbox/config?
Are the tokens for your gateway unique? and matching in the two files? ./cloudfoundry/.deployments/devbox/config/cloud_controller.yml and ./cloudfoundry/.deployments/devbox/config/**_gateway.yml**
I would recommend that you first concentrate on getting the echo service to be listed in the vmc services output. Once done with this you should replicate the steps (with absolute care to modify things like the token) to get your custom service working.
Cheers,
Ankit
You should follow this guide
It work to me.
regards.