verifyByHash

Signature

TypeScript

const matches = await fidemark.verifyByHash(contentHash, options);

Python

matches = fidemark.verify_by_hash(content_hash, options)

Go

matches, err := client.VerifyByHash(ctx, contentHash, opts)

Returns an array of attestations, sorted newest-first.

Why this exists

verify(uid) answers “what does this attestation say?”. verifyByHash(hash) answers “who has attested this content?”, useful when:

• A platform wants to surface every signature on a piece of media.
• A creator wants to find duplicate or competing claims on their work.
• An indexer needs to enumerate attestations for batch processing.

Implementation

By default the SDK queries the resolver’s HumanAttestation and AIAttestation events filtered by the indexed contentHash topic. Both events index the hash, so the lookup is cheap on local + Sepolia. On busy mainnet RPCs the full-deployment-range eth_getLogs can be slow or rate-limited; in that case configure an EAS GraphQL indexer instead.

Indexer modes

All three SDKs accept the same trio of modes:

Mode	Behaviour
events	Default. Scan the resolver logs via the configured RPC.
graphql	Query an EAS GraphQL endpoint and surface errors directly. Requires a URL or client.
auto	Query the indexer first; fall through to the event scan on any error. Picked automatically when you pass a URL or client.

TypeScript

const fidemark = new Fidemark({
  network: "base",
  privateKey: process.env.PRIVATE_KEY,
  indexer: "auto",
  indexerUrl: "https://base.easscan.org/graphql",
});

Python

fidemark = Fidemark(
    network=get_network("base"),
    private_key=os.environ["PRIVATE_KEY"],
    indexer="auto",
    indexer_url="https://base.easscan.org/graphql",
)

Go

client, err := fidemark.New(fidemark.Config{
    Network:    network,
    PrivateKey: os.Getenv("PRIVATE_KEY"),
    Indexer:    fidemark.IndexerAuto,
    IndexerURL: "https://base.easscan.org/graphql",
})

You can also inject a custom client (e.g. with auth headers, custom timeouts, or to mock GraphQL in tests) via indexerClient / indexer_client / IndexerClient.

Options

TypeScript

{
  type?: "human" | "ai",   // restrict to one schema; default: both
  fromBlock?: number,      // start of scan; defaults to network.deployBlock
  toBlock?: number | "latest",
}

Python

VerifyByHashOptions(
    type="human" | "ai" | None,
    from_block=None,
    to_block=None,  # int or "latest"
)

Go

fidemark.VerifyByHashOptions{
    Type:      fidemark.SchemaHuman, // or SchemaAI, or "" for both
    FromBlock: 0,                    // 0 -> network.DeployBlock
    ToBlock:   0,                    // 0 -> latest
}

Example

Complete, copy-pasteable runnable. Read-only call: no signer required. See Configuration for every constructor option.

TypeScript

import { Fidemark, getNetwork, hashContent } from "@fidemark/sdk";

const fidemark = new Fidemark({ network: getNetwork("base-sepolia") });

const hash = hashContent(myArticle);
const matches = await fidemark.verifyByHash(hash, { type: "human" });

console.log(`${matches.length} human attestations on this article.`);

Python

from fidemark import Fidemark, VerifyByHashOptions, get_network, hash_content

fidemark = Fidemark(network=get_network("base-sepolia"))

hash_ = hash_content(my_article)
matches = fidemark.verify_by_hash(hash_, VerifyByHashOptions(type="human"))
print(f"{len(matches)} human attestations on this article.")

Go

import (
    "context"
    "log"

    "github.com/fidemark/sdk-go/fidemark"
)

network, _ := fidemark.GetNetwork("base-sepolia")
client, err := fidemark.New(fidemark.Config{Network: network})
if err != nil { log.Fatal(err) }

hash := fidemark.HashContent([]byte(myArticle))
matches, err := client.VerifyByHash(context.Background(), hash, fidemark.VerifyByHashOptions{
    Type: fidemark.SchemaHuman,
})
log.Printf("%d human attestations on this article.", len(matches))