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IPFS (the InterPlanetary File System) is a new hypermedia distribution protocol, addressed by content and identities. IPFS enables the creation of completely distributed applications. It aims to make the web faster, safer, and more open.

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How to add/create a folder to IPFS via API? [closed]

So my question is pretty straight forward, I have been digging on the web to find an answer for this but there is nothing helpful really. Just for the sake of context, I am building a file upload/...
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2answers
51 views

How do I update data for project using blockchain (Ethereum)?

I am very new to creating blockchain dapps, so some guidance would be appreciated. I am conceptualizing how to approach creating a private blockchain so that users can communicate about the status of ...
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1answer
62 views

IPFS file download

I wanted to check that is there any way i can download the IPFS file without running the local demon. I am working on a Dapp where i will be uploading the files over IPFS and sending the link of it to ...
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1answer
25 views

How to encrypt file before storing into IPFS network in Javascript? [closed]

I want to encrypt file before storing into IPFS network so that only person who is uploading a file should be able to decrypt.
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1answer
43 views

Ipfs.files.add promise throws error [closed]

I'm trying to upload a simple image file to IPFS using ipfs.files.add(). However, I can't seem to figure out why the promise throws an error. Here's the code: $(function() { $(window).load(...
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1answer
25 views

IPFS Config on windows 10

I'm trying to execute these commands on windows 10 ./ipfs config --json API.HTTPHeaders.Access-Control-Allow-Origin '["*"]' ./ipfs config --json API.HTTPHeaders.Access-Control-Allow-Methods "[\"PUT\",...
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1answer
38 views

DApp using IPFS Ganache and MetaMask

I am following a tutorial (hosted by dappuniversity) on youtube regarding DApps using IPFS. I have done exactly everything as mentioned in the tutorial but i get this errors: GET https://ipfs.io/ipfs/...
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1answer
30 views

How can I connect my static page (Dapp) to my ipfs node?

The very naive way I'm going about it is: const node = new Ipfs({ host: "xxx.ip.address.xxx"}); When I save an image from the static page, it does give me an ipfs hash back and save it to the local ...
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21 views

IPFS in android using java

need pro help over here. I have an android project that use IPFS (InterPlanetary File System) to transfer few files and get the keys to store. I been searched in various online pages and read lots of ...
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1answer
137 views

How long do my files stay on IPFS when I upload it?

I'm trying to grasp the concept of how IPFS works. Say if I upload 1GB of data to IPFS. How long does it stay there? Or do I have to leave my computer on at all times for the file to be live on the ...
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2answers
135 views

Upload file to IPFS from HTML page

I am trying to upload the file to IPFS from HTML page and below is my code but I am getting below error. Uncaught ReferenceError: Buffer is not defined I have imported below statements <script ...
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3answers
127 views

RE-Encrypt file in IPFS

If I have an encrypted file in IPFS with a symmetric key that I share, can I after that decrypt and re-encrypt that file with a different key in order to revoke access?
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1answer
25 views

How to generate thumbnails from IPFS URL?

I am trying to design a dapp which displays files uploaded to IPFS by a user. On my web page, I wish to display thumbnails of all the files uploaded by him. For this, I designed below mentioned EJS ...
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2answers
52 views

Decentralized dapp music player using smart contracts on ethereum?

Has anyone made a decentralized music player on ethereum using smart contracts? Say if I wanted to upload a mp3 file to IFPS and everytime someone plays the midi file the smart contract will deduct ....
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1answer
27 views

How to pass and store more than 16 arguments in a contract [duplicate]

I'm trying to create a contract which stores simple user profile information like name, email, age, address, etc (all string/bytes type) and I've come across the size restriction issue when passing ...
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2answers
197 views

MongoDB vs Ethereum Swarm

I am designing a DAPP. I have two options available for storage MongoDB OR Ethereum swarm(OR IPFS). As MongoDB also replicates data to multiple shards fault tolerance is available in MongoDB. What ...
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1answer
46 views

What would an Etheruem-like blockchain look like if each block were just an IPFS hash?

I see a lot of people tout the enormous benefits of using IPFS as a store of data. Meanwhile, the Ethereum blockchain is over 1TB in size, with quesitonable need to keep the earlier blocks. In ...
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0answers
66 views

Oraclize and IPFS integration through Nucypher

I am trying to build a blockchain which will store the data in IPFS, but it will be private (and encrypted) but the user can share this data by using Nucypher. But I need my smart contracts to access ...
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1answer
135 views

Storing data on IPFS using KMS and ethereum

I am trying to build a blockchain on ethereum but keeping the data related to blocks in some distributed file storage system like IPFS or Storj and storing the hash of data in blocks. But we need our ...
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0answers
45 views

Evaluation of DApp (Smart Contract) storage concept with IPFS

i hope you can help me improve or validate my storage concept. I am glad for each suggestion. Since this is my first DApp, i might not consider all possible options for my problem. To understand the ...
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1answer
167 views

Transaction's data vs Smart contract's data

with reference to this question. Store specific data related to users I wanted to ask is there any difference between transaction's data and smart contract's data? how is transaction's data is ...
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1answer
67 views

Does Swarm caches blocks like IPFS do?

When we retrieve a file through IPFS, it caches the file in IPFS' repository. Later when we want to fetch the same file or its updated version, only block that contains the changed character will be ...
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1answer
70 views

A byte array with super large size : is this practical in Solidity?

I want to store cells of an Excel file with 94 rows and 104 columns (it means 9776 cells!) in a byte array as follows : I define my array as follows : struct StateStruct { bytes32 ...
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2answers
211 views

How to store hash of an Excel file in Blockchain? [closed]

I'm sorry if this question does not seem to be logic. I want to store hash of an Excel file in Blockchain by following function : //byte fileHash; event LogsetFileHash(byte _hashValue); ...
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1answer
181 views

Can IPFS protect privacy? [closed]

I understand IPFS is public by design but can a record be placed in IPFS which is accessible only by the owners? Or accessible and readable (but excluding encryption solutions). Edit - This site has ...
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1answer
147 views

How to display a list of ERC721 items starting from a pubblic address

I'd like to understand more about this ERC721 non-fungible tokens. I bought some cryptokitties (non 721), some art on KnownOrigin and now I want to display them in a web page. For Cryptokitties I'm ...
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1answer
506 views

Is it possible to derive public key from ETH address?

Goal (not asking XY question): send ETH to an address web3.js script monitoring it and acting upon transaction if msg.value > 0.1 ether then... ...encrypt a file with the public key of the msg....
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0answers
50 views

couldn't connect node ec2 (private blockchain)

I build private blockchain on ec2 and I use public ip (http) to connect to my website (web3) when I test web on localhost. it can connect to private blockchain but if I test website from ipfs (https). ...
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3answers
654 views

How long does Infura store a file on IPFS?

You can send files to Infura's IPFS servers but I don't know about the limits. How long is it stored for? What's the size limit?
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2answers
271 views

how ipfs work in ethereum blockchain [closed]

currently i am learning ipfs and ethereum based blockchain technology,I wanted to know can we store data on ethereum blockchain and yes then how. and also wanted to know how exactly ipfs work for ...
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2answers
472 views

Store and retrieve data of MongoDb documents using hash which is stored in blockchain

Blockchain can not store and shall not be used to store all the data of users. There are 2 reasons for that - 1) To store data in blockchain requires gas price (transaction cost) 2) Since all blocks ...
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1answer
40 views

Documenting an DApp components

I am new to building decentralized applications and i am trying to document the process of building an DApp. Waht are the components as well as installations that are needed to build An Dapp ? (if is ...
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1answer
77 views

Organize storage of JSON array

I'm developing a Dapp based on Ethereum and I'm facing a problem that I don't know how to properly solve. I need to store a very big JSON array composed by more or less 10k object where each object ...
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4answers
187 views

Accessing DAPPs through HTTP

The blockchain is all about serverless and removing the third party. But I saw many DAPPs accessible through HTTP. Isn't this breaking the serverless concept? I read in a lot of places that IPFS aims ...
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1answer
102 views

How fast and scalable is a Dapp build on ethereum?

I am a beginner to Dapps on ethereum and smart contracts but I wanted to ask three questions on building on top of ethereum. Firstly, how fast would an Dapp with a token will the transactions per ...
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1answer
80 views

What is the right way to access DAAPs?

I am a newbie and I am a bit confused about the deploying process of the DAPPs, I have some unclear points Can I access DAPPs outside Mist browser? Can I access them using Chrome for example? ...
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2answers
119 views

Ethereum vs InterPlanetary

I've been reading about Ethereum and it's fundamentals for a while now. I wonder what is difference between Ethereum and InterPlanetary File System ?
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1answer
111 views

IPFS hash algorithm

How actually is an IPFS hash (ipfs add) is generated? I'm looking for step by step operations done on input(bytes/string) to get output(in this case IPFSHash)
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1answer
83 views

Using web3.js to do base58 (ipfs) encoding and decoding?

Is it possible to use the web3.js libary to do base58 encoding and decoding? It seems that web3.js includes the bignumber library, but I'm unsure as to whether this can handle the base58 encoding ...
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3answers
531 views

Does it cost gas to access data stored on the IPFS with a smart contract?

I want to store about 4MB of data on the IPFS. I then want to create a smart contract that can access the data or a subset of the data on the IPFS. I know that data already stored on the Ethereum ...
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5answers
513 views

IPFS conditional access control through ethereum smart contracts

This question is about combining IPFS with Ethereum smart contracts to check conditions and encryption to restrict access. One-on-one file sharing with a known recipient is not an issue. The 'sender' ...
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1answer
42 views

Query multiple derived contracts from contract factory

Say a contract factory is used to spawn multiple child contracts, each with associated data within them. The contract factor stores all addresses of the derived contracts along with a unique name of ...
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1answer
114 views

IPFS code needing extra JS Scripts with Solidity

So I created a truffle folder for solidity, wrote down the basic test.js and ipfsContract.sol needed (Creating a form in IPFS for users to enter data). HOWEVER, on doing truffle test I get 0 passing ...
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0answers
83 views

I get some “POST 404 (Not Found)” when I deploy the IPFS webui in production

I followed all the guidelines to deploy property this helpful tool. When I make it in my local machine, all works fine. But when I try to deploy the same in a production server, it shows me some 404 ...
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0answers
55 views

Restrict participation in ipfs network

Is it possible to restrict new nodes from accessing the IPFS network? Something like requiring a certain identification from each new node before it can be added to the private network.
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4answers
329 views

Would it make sense to use a SQL database to store the data of a Dapp?

Let's say that I want to develop a Dapp and I need to store different information about the users. This information must not be public as not all the users are allowed to see all the information ...
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1answer
159 views

Where do you save the application data of a Dapp?

Let's say that I want to implement a Dapp similar to Facebook. Each user has its own profile, pictures and information. Usually you would use a database to store all this data. This guarantees that ...
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1answer
143 views

No output when writing data to IPFS and storing its hash through Solidity

So I am using truffle. Following from Creating a form in IPFS for users to enter data [check the code in answer], doing some changes: Contract name - IpfsContract.sol test.js uses the following JSON ...
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1answer
340 views

Merkle Tree in IPFS

How is Merkle Tree(DAG) exactly related to IPFS? I observe that unlike Blockchain, IPFS doesn't require level wise hashing. How all data is hashed in IPFS?
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1answer
771 views

Creating a form in IPFS for users to enter data

I wanted to create a website and upload it onto the IPFS for users to upload data (like their picture, name etc.). But how exactly can I capture all details user upload, get the IPFS Hash produced ...