17 votes
Accepted

Garbage Collection

Each Tezos node maintains a representation of the current state of the ledger. That state includes things like the storage of each contract, the balance of different addresses, etc. The goal of the ...
Arthur B's user avatar
  • 4,599
7 votes

How is the hash code of blocks generated?

Take a byte representation of a particular block header: http://rpc.tzkt.io/mainnet/chains/main/blocks/head/header/raw. The format of the block header is described in the docs. Get a BLAKE2b (32bit) ...
Michael Zaikin's user avatar
6 votes
Accepted

Is it possible to 'destroy' a wallet?

I am talking from memory of the transition from proto 002 to proto 003 so hopefully I got it right. If you go on tzscan you will see that there is a counter for addresses https://tzscan.io/...
Ezy's user avatar
  • 6,064
5 votes
Accepted

How is chain_id computed?

The chain_id is computed from the genesis block hash as follows. First, in pseudocode: tezosB58CheckEncode('Net', firstFourBytes( blake2b(msg = tezosB58CheckDecode('B', genesisBlockHash), ...
Tom's user avatar
  • 2,506
5 votes

Can I know when a wallet was created?

My suggestion would be using tzscan API. For example checking all activations until you find a match something like this: index = 0 loop while true GET https://api1.tzscan.io/v1/operations?type=...
Rodrigo Quelhas's user avatar
4 votes
Accepted

Current level of block-chain

You can request the current head of your node using ./tezos-client rpc get /chains/main/blocks/head (and look for the level and hash information). Then, use your favorite block explorer to know the ...
vect0r's user avatar
  • 756
4 votes

What does it mean when someone double bakes or double endorse?

Double baking is the act of creating two blocks at the same level - this in effect creates a fork, where the next bakers can choose from multiple blocks. Endorsements help to improve the fitness of ...
Stephen Andrews's user avatar
4 votes
Accepted

Is Tezos formalized or is it defined by the behavior of a program?

The Tezos protocol is defined by its OCaml implementation. When amendment to the protocol are proposed, the delegates vote on hashes of amended implementations. That being said, some parts of the ...
Raphaël Cauderlier's user avatar
3 votes
Accepted

How do offchain views work and what guarantees do they provide?

You basically have no guarantee of synchronicity for several reasons. We’re talking about a blockchain with no instant finality (yet) so a transaction can be “reversed” in the (real world) future so ...
FFF's user avatar
  • 3,260
3 votes

Is Tezos blockchain vulnerable to "frontrunning"?

Choosing the order in which operations are applied is a privilege of the baker. So yes, frontrunning is possible on Tezos and can either be done by setting high fees (the default baker strategy is to ...
Raphaël Cauderlier's user avatar
3 votes

Is it possible to 'destroy' a wallet?

If there has been any transactions to or from any of these wallets they will be on the chain forever. You can "forget" them on your tezos node using: tezos-client forget address <name> -f The ...
asbjornenge's user avatar
  • 1,973
2 votes

Garbage Collection

If you are interested in a study on the impact of storage improvements, see here (there is also a link towards a storage-efficient tezos node).
lefessan's user avatar
  • 3,308
2 votes

How much percent of participants does tezos need to achieve consensus?

For the current consensus protocol, Emmy*, the attacker needs at least half of the total stake, since it's a Nakamoto-style algorithm (like Bitcoin and Ouroboros). For the consensus algorithm of the ...
Eugen's user avatar
  • 1,000
2 votes

Creation of a FA2 Token (Fungible) and not an NFT

FA2.0 standard doesn't describe how to distinguish NFT from non-NFT, so there is actually no way to precisely tell what your token is. TzKT uses heuristics to classify tokens. In particular, it ...
Groxan's user avatar
  • 2,731
1 vote
Accepted

Issue while generating NFT metadata

From what I see it's now working. It may take quite some time for IPFS nodes to synchronize and/or explorer to gather them. I suggest you to always test with tzcomet, that gives more info: https://...
Jordan_tez's user avatar
  • 1,065
1 vote
Accepted

Creation of a FA2 Token (Fungible) and not an NFT

There are two Token Standards on Tezos. FA1.2 and FA2. There is no separate standard for NFTs. So this is indeed correct, FA2 standard is an Multi-Asset Interface, also the NFT abbreviation stands for ...
David's user avatar
  • 82
1 vote
Accepted

Integrate a url in an NFT during the mint

The sp.string type cannot contain / and is not suited for URLs. Instead you can use the sp.bytes type. That said, the URL should probably be included in the metadata. So I suggest you not to modify ...
Jordan_tez's user avatar
  • 1,065
1 vote
Accepted

Generate Tezos Wallet and use it

You could use beacon wallets, like Kukai or Temple. This would be the safest way for your users. Nevertheless, Tezos Taquito Javascript library allows you to create wallets with what is known as "...
Luiz Milfont's user avatar
1 vote

Manipulable block hash by baker

blockhash can be manipulated by every single endorser. It should be avoided to be used as source of entropy.
Papers.ch's user avatar
1 vote
Accepted

Is it possible to create secure guessing game on chain?

You can use commit/reveal pattern, for turn based game it works well. Here a template in CameLIGO you would be able to adapt to your use case: https://github.com/ligolang/randomness-cameligo
Thomas's user avatar
  • 380
1 vote
Accepted

How to simply store signed, hashed data on Tezos blockchain?

You will store the information in a smart contract. (await <...>.send()).hash will give you the operation hash. In this example you can click Run code to obtain the operation hash.
Rodrigo Quelhas's user avatar
1 vote
Accepted

How to get all NFT(Non Fungible Token) which created on the specific smart contract of the Tezos blockchain?(getNftForContract)

take a look at https://github.com/teia-community/teia-docs/wiki/Tools-made-by-the-community#open-indexers You can also try https://api.tzkt.io/#tag/Tokens
catsoup's user avatar
  • 106
1 vote
Accepted

How to retrieve the transaction details using Operation Hash in Taquito

If you want to do it with Taquito, the confirmation method on the operation object returns a promise with different information like the block, the status, etc. You can also use confirmationObservable ...
Claude Barde's user avatar
1 vote

I cannot connect to my sandbox

The src/bin_node/tezos-sandboxed-node.sh script that launches a sandboxed node is meant to be used with the src/bin_client/tezos-init-sandboxed-client.sh one that sets some env variables and bash ...
Raphaël Cauderlier's user avatar
1 vote

Current level of block-chain

Here's my goto command. tezos-client rpc get /chains/main/blocks/head/ | jq -r '.header.level, .header.timestamp';date --iso-8601=seconds The output will look something like: 544640 2019-07-31T10:...
Richard Ayotte's user avatar
1 vote

Baking Tezos with Kiln: deviating BC source path

If you didn't figure this out: You can actually change the directory that kiln uses for the tezos node data. It's a bit odd that the symlinks break things, but you ought to be able to not need a ...
BenKolera's user avatar
1 vote

How is the hash code of blocks generated?

Part 1 of my question was answered by Michael. What about the second part? Well, I just had a look at it. What I did is: extract the full series of hash codes, from block 1 to the latest (VERY LONG). ...
luchonacho's user avatar

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