The bridge between traditional web data and blockchain smart contracts. Bring any API data onto the Flare network with cryptographic proof.
Think of FDC as a trusted messenger that can fetch data from any website or API and deliver it to your smart contracts with a cryptographic proof that the data is authentic.
It's like having a notary public for internet data - it verifies that the information came from the source you requested and hasn't been tampered with.
Imagine you want to build a DeFi app that uses stock prices from Yahoo Finance.
With FDC, you can tell it: "Go get me Apple's current stock price from Yahoo Finance" and it will bring back the price along with proof that it really came from Yahoo.
Your smart contract asks FDC to fetch specific data from a web API. You specify the URL, the data you want, and how to extract it.
FDC calls the API, gets the response, and creates a cryptographic proof (attestation) that proves the data came from that specific source at that specific time.
The data and its proof are delivered to your smart contract. Your contract can verify the proof to ensure the data is authentic before using it.
📊 FDC Data Flow Diagram
Connect to REST APIs, JSON endpoints, or common web services. Stock prices, weather data, sports scores, and more. If it is available online, FDC can bring it on chain in a trusted way.
Every piece of data comes with a verifiable attestation. This removes blind trust and makes it possible to prove that your data is authentic using mathematics.
Fetch updated information when your contract requires it. This keeps your smart contracts connected to data that changes often.
Pay only for the data you use. There is no need to run your own oracles or manage separate infrastructure for every data source.
Multiple independent attestation providers reduce the chance of failure. Your data remains reliable and available even if one provider has issues.
Simple integration into your smart contracts. Clear documentation and flexible options make it easy to start building with FDC.
Here's a basic example of how you might use FDC to get cryptocurrency prices from an external API:
Lines 1-8: We define the FDC interface so our contract knows how to talk to it
Lines 10-17: Our contract stores the FDC address and sets up the owner
Lines 19-26: We ask FDC to fetch Bitcoin price from CoinGecko API
Lines 29-33: FDC calls this function back with the verified price data
| Feature | Flare Data Connector | Traditional Oracles |
|---|---|---|
| Data Sources | Any web API or endpoint | Pre-defined data feeds only |
| Setup Time | Minutes to integrate new APIs | Days or weeks for new feeds |
| Cost | Pay-per-use model | Subscription fees |
| Flexibility | Full control over data parsing | Limited to provider's format |
| Verification | Cryptographic attestations | Trust in oracle provider |
An attestation provider is a trusted service on Flare that collects data from the real world or other blockchains, then sends that data on chain. It helps smart contracts use information outside their own network.
A cryptographic proof is a math based way to prove something is true without showing every detail. It keeps information secure and verifiable.
Some services only allow a limited number of requests within a short time. Sending too many requests may cause slow responses or temporary blocks. Always handle errors and add retries in your code.