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Working on a collectible card game based on ERC721 with the metadata extension. When a person "collects" a warrior, it is successfully "minted" to the owner and the tokenURI is successfully set to the path of the json file with the metadata (name, description, image path) in it. My question is how do I now get that metadata (especially the image) so I can show it on my website? I have a page that displays the warriors the person has collected. On that page I'm successfully getting the info for the warrior structs and painting to the page. Here's that code I have in my app.js file: function getWarriorsByOwner(owner) { return new Promise(function (resolve, reject) { App.contracts.WarriorFactory.deployed().then(function(instance){ instance.getWarriorsByOwner.call(owner) .then(function(warriors){ resolve(warriors); }); }); }); } function displayWarriors(ids) { $("#warriors").empty(); for (id of ids) { // Look up warrior details from our contract. Returns a `warrior` object getWarriorDetails(id.toNumber()) .then(function(warrior) { // Using ES6's "template literals" to inject variables into the HTML. // Append each one to our #warriors div $("#warriors").append(`<div class="col-md-4"> <div class="card mb-4 shadow-sm"> <img class="card-img-top" src="" alt="Card image cap"> <div class="card-body"> <h5 class="card-title card-name">${warrior[0].toString()}</h5> <strong>Attack</strong>: ${warrior[1].toString()}<br/> <strong>Defend</strong>: ${warrior[2].toString()}<br/> <strong>Strategy</strong>: ${warrior[3].toString()} <strong>Cards Issued</strong>: ${warrior[4].toString()} <strong>Total Cards</strong>: ${warrior[5].toString()} </div> </div> </div>`); }); } } So, if a person owns warrior 0 in the warriors array, I get all the attributes for that warrior. If I call tokenURI(0) I also see the correct path to the json file with the rest of the info in it that I don't keep on chain. What would I need to add to also read the correct json file and set the image source here in the above: <img class="card-img-top" src="" alt="Card image cap"> I'm very new to this which means I know just enough to be tempted to do very stupid things, the above may be an awesome example of just that. Any advice? Thanks, Kevin
Posted by Kevin 26 days ago
somehow my metadata is not showing up and i don't know why: https://opensea.io/assets/0xa87a42351e2ad8c613370f4ef506d2d1d8b1e4f0/1 the tokenURI: https://von-aesch.com/tokenURI.php?colors=VA_DIAMONDS-E2635C-E2635C-BCD78D-BCD78D-BCD78D-BCD78D-E2635C-E2635C-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D-BCD78D how can i debug the metadata? is there an opensea parser to validate it?
Posted by KM about a month ago
Hi! Like it talks about in this thread https://github.com/ipfs/ipfs/issues/181 what are the chances of OpenSea supporting generic IPFS URLs of the format fs:/ipfs/<hash> or /ipfs/<hash> in the tokenURI calls of our ERC721 contracts?
Posted by Wil Bown about a month ago
Any good starting points for where to learn how to generate/create the metadata json objects for the tokenURI to point to? I know that if I have a dapp at http://mycardgame.com and a tokenId of 6 that it would point to something like http://mycardgame.com/cards/6 . What I need help learning is how do I create that json for card 6 when the token is minted? I suspect that I may not even know enough about that to have even asked the question the right way...
Posted by Kevin Phillips 3 months ago
Complete newbie here so this is probably a dumb question. If I'm building a card game and the "characters" have different starting level, attack, etc. attributes, and I want the characters to be able to "level up", would it be feasible to store those in the metadata json file for the character? I've messed around with solidity a bit and have been able to change attributes for a character that I store in a struct, but am wondering if the json for a character could also be updated by javascript or something of that nature. Seems if you could do that it would keep transactions on the blockchain down (saving gas). Thanks in advance for any advice. Kevin
Posted by Kevin Phillips 3 months ago
Hello, I am working on adding the metadata of a token, should I use setTokenURI function from the contract? I tried several times of putting json data using it, but it does not work, it seems that I need to put a url in stead of actual json data. May I know if I need to host a website that shows the json data and then use the function in the format of setTokenURI(ID, "http://xxx.com/") please? If it works like this, what happened if the website is down? Thanks!
Posted by Jack 4 months ago
I'm testing my NFT at your platform, but there is on issue - unicode symbol not showing correctly. for example the name of the contract: https://rinkeby.opensea.io/assets/0x85e3dcfa057acfc072234de9a33c15194304c37b/1 your system shows: "â CRYPTOHEROES GAME â" but it should be "⚔ CRYPTOHEROES GAME ⚔" Can you fix it?
Posted by Mikhail Semenkin 4 months ago
Hi, this is the error that shows the Pragma Editor with the Deploy option after paste the codeof CryptoPuff Sample Contract= :2:1: ParserError: Source "openzeppelin-solidity/contracts/token/ERC721/ERC721Token.sol" not found: File not supplied initially. import 'openzeppelin-solidity/contracts/token/ERC721/ERC721Token.sol'; ^--------------------------------------------------------------------^ How can solve this? Thanks
Posted by capir 4 months ago
Hi, I looked at your FAQ page, and have a couple of questions. 1. What do you typically suggest for creating meta data file automatically when minting? Do we need to handle this inside the solidity contract (I assume not?) or make a hook to an external script that writes the metadata to a file while minting (and thus creating a new collectible image)? 2. For contract redeployment from v1 to v2, for instance, how can we easily move all v1's minted token data to v2? Moving all these v1 transactions to v2 causes additional gas, correct? Is it suggested to just read the token data from v1 and just import to v2 or?!? Any suggestions are welcome! Thank you for previous responses!
Posted by Mark 5 months ago
Hi, I was reading through your page here: https://docs.opensea.io/docs/4-auctioning-an-item Is it possible to auction an item using the sample contract you have on this page? https://docs.opensea.io/docs/1-structuring-your-smart-contract I initially thought I would have to have the solidity code to take care of "auctioning" piece, but the above sample code doesn't appear to have the auctioning details in the solidity code. Is this auctioning automatically taken care of by the Opensea platform itself? Ultimately, I am asking if I can just take your sample code, deploy it on testnet, pull it into opensea, and make auctioning work with the sample code without me coding the auctioning piece. Thank you!
Posted by Mark 6 months ago
Hello, I am currently developing a smart contract that will create ERC721 tokens. I am interested in using your auction features in the future and currently adding a metadata contract. I looked up your documentation on adding metadata at https://docs.opensea.io/docs/2-adding-metadata. Everything in the documentation is pretty clear but I don't understand this portion "external_url": "https://cryptopuff.io/3". We are building a single page application (SPA) that by nature does not have unique URLs. If my metadata wont include an external URL would that be an issue? My metadata will include a link to the image of the token. Thank you for your time, Oleg Mitrakhovich
Posted by Oleg Mitrakhovich 6 months ago
I am a bit confused on the actual image creation. In the guide to add metadata, the reference to an image was: https://storage.googleapis.com/opensea-prod.appspot.com/puffs/3.png Does this mean we need to have the images stored somewhere else to point to in advance, and then create a metadata pointing to it? This would also mean I would need to have a separate mechanism to create images and upload to the image host location prior to creating metadata? Or is this automated as part of the Opensea implementation? Thank you.
Posted by Mark 6 months ago
Hi - I'm trying to deploy the crypto puff tutorial using pragma. Is there full implementation (including the inheritance of 10 sub contracts ; basic.sol/safemath.sol erc165 etc etc) or am I missing something? Not finding open zeppelin easy here!... Thanks
Posted by tom alcott 7 months ago
Once a test contract is deployed with Truffle on Rinkeby, how do you run this scripts/mint.js to actually mint? Is this run under truffle with truffle exec with proper environmental variable set (like one for CONTRACT_ADDRESS, etc) or just run it in command prompt with node? I get this error: truffle exec ./scripts/mint.js --network rinkeby Using network 'rinkeby'. TypeError: fn is not a function at /usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-require/require.js:128:1 at /usr/local/lib/node_modules/truffle/build/webpack:/~/truffle-require/require.js:101:1 at FSReqWrap.readFileAfterClose [as oncomplete] (fs.js:442:3)
Posted by M 7 months ago
Hi, I asked same question here for the rinkeby test net token. I deployed same in main net, but it still does not get listed automatically. https://opensea.io/category/digitalartchain Can you please fix this as well? Also can you tell me what is the right path to fix this? I guess every time asking here is not good solution for you. Thank you in advance!
Posted by Maki Ooki 10 months ago
Hi I'm Maki, ethereum based dApps developer in Japan. I want to put my Dapp on Open Sea My Dapp enable user upload image and create ERC721 token which can be used in Dapp I tested in rinkby network: https://rinkeby.opensea.io/assets/digitalartchaintoken DigitalArtChainToken | OpenSea But this is not getting updated when user create new token. Is it possible to have page which is updated frequently? One more question , can I use my contract auction logic? I have logic to make benefit for publisher of digital Art.
Posted by Maki Ooki 10 months ago