Bumblebee
  • Member for 4 years, 10 months
  • Last seen more than a month ago
Truffle Migrate doesn't work: Error: No network specified. Cannot determine current network
13 votes

I had the same problem with truffle 4.0.1. After some investigation and advise from the truffle team I figured out that truffle 4.0.x has a new option. If you run truffle develop you don't need ...

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What data should we maintain in blockchain?
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6 votes

In general the blockchain is not meant to to save a lot of data. Data storage in ethereum is quite expensive. One approach would be to save a hash of the data in the blockchain and store the actual ...

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Is the address used to deploy contracts in JS tests in truffle always accounts[0]
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5 votes

Yes that is the case. accounts[0] is the default. If you like to test to call a function form an another account you can pass {from: accounts[1]} as the last parameter of your function. If you would ...

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Change truffle develop port
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3 votes

You could also add another network to your truffle.js file. Something like this: networks: { development: { host: "localhost", port: 9545, network_id: "*" // match ...

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Truffle vs Meteor
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3 votes

Meteor and Truffle are two different frameworks. As you already experienced Meteor is a javascript framework to design single page web applications. Truffle can be used to devlop and test smart ...

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How to build an API that communicate with Smart contract Event?
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2 votes

You would want to use the web3 module. The installation via npm works like this npm install -g web3 Make sure that you install web3 1.0 There is one thing you have be careful about if you want to ...

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What were the first 5 technical steps in launching Ethereum?
2 votes

It depends a little bit of what you want to do with ethereum. If you want to get started with ethereum you have to install different tools. Install geth. geth is the the command line interface for ...

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Which contract(s) are exceeding block gas limit? (truffle.js)
2 votes

I run into the same problem with truffle 4.0.1. After some investigation and advise from the truffle team I tried it with truffle develop and everything worked fine again. If you use truffle develop ...

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How can I add some balance to the address in private blockchain testnet?
2 votes

You can run the command: miner.start() In the geth console. This will start mining and add ether to your default account.

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Getting notified after receiving tokens
1 votes

One way would be to use events in the smart contract which receives the the ETH or Tokens. When the function in the contract, which will receive the ETH or tokens, will be called an event can be ...

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Web3js - "The returned value is not a convertible string"
1 votes

web3 cannot handle strings which will be returned from a solidity function. You have to return a bytes32 value. I recommend that you store your values (latitude, longitude etc) as bytes32 values and ...

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Permissioned blockchain for company
1 votes

Have a look at https://www.jpmorgan.com/global/Quorum Quorum is a Enterprise-ready distributed ledger and smart contract platform which is based on ethereum. Quorum has some additional features like. ...

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Safe to assume that Ethereum transactions are as fast as a client-server architecure and SQL database?
1 votes

I'm not quite sure whether ethereum is the best choice for this kind of application There are projects out there which were developed for internet of things. You should have a look at https://iota.org

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unable to use testrpc with ethereum wallet
1 votes

If you are working with truffle you could also use truffle develop instead of testrpc. You can start a truffle develop console with truffle develop. Inside the truffle develop console you can deploy ...

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HelloWorld contract using truffle v3.2.1
1 votes

In order to make life a little bit easier you can also do it like this: First you can assign the contract to variable: truffle(development)> HelloWorld.deployed().then(function(instance){...

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Private testnet transaction submitted but not executed
1 votes

That is the result of: eth.getTransactionReceipt("0xf6d91e281de023f09169ce4576a45428a0171b40b285a01660e6ae3a23151d33")` { blockHash: "...

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Quorum: Can't Connect To Nodes From External Sources
0 votes

You have to find out the ip addresses of the virtual machines. Let's suppose the ip of the virtual machine you want to connect to is 172.13.0.3. Then you can connect to the node with geth attach http:/...

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Final year Project using Block-Chain technology
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0 votes

In general you have basically endless possibilities where you can use block-chain applications. Check this website: https://blockgeeks.com/guides/blockchain-applications/ Maybe you can get some ideas ...

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Connecting to an ethereum node from meteor server side
0 votes

I had the same problem and finally found the solution. I followed this guide and it worked. https://github.com/ethereum/wiki/wiki/JavaScript-API#usage Web3 has to be decleared like this: var Web3 = ...

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Truffle sample Dapp doesn't show Metacoin balance when Metamask is active
0 votes

Another possibility would be to start testrpc with the -m and the -u options. The -m option requires a string of the words you got when you first installed the Metamsk. The -u option unlocks the ...

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How to delete contract records in mist wallet
0 votes

In your Ethereum Walltet click on contracts and then click on the contract you want to delete. When the contract is displayed move your mouse pointer on the contract name. Then you will see a trash ...

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An online voting system using blockchain technology
0 votes

This might be a good starting point: https://solidity.readthedocs.io/en/develop/solidity-by-example.html#voting

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