discv5/enr_tree.hpp

Namespaces

Name
discv5

Classes

	Name
struct	discv5::EnrTreeUrl Parsed EIP-1459 ENR-tree URL.
class	discv5::EnrTreeResolver Resolve EIP-1459 DNS discovery trees into ENR URI seed records.

Types

	Name
using std::function< std::vector< std::string >(const std::string &name)>	DnsTxtLookupFn DNS TXT lookup callback used by the ENR-tree resolver.

Types Documentation

using DnsTxtLookupFn

using discv5::DnsTxtLookupFn = std::function<std::vector<std::string>(const std::string& name)>;

DNS TXT lookup callback used by the ENR-tree resolver.

Source code

// Copyright 2026 Genius Ventures, Inc.
// SPDX-License-Identifier: MIT

#ifndef EVMRELAY_INCLUDE_DISCV5_ENR_TREE_HPP
#define EVMRELAY_INCLUDE_DISCV5_ENR_TREE_HPP

#include <functional>
#include <string>
#include <vector>

namespace discv5
{

struct EnrTreeUrl
{
    std::string public_key;
    std::string domain;
};

using DnsTxtLookupFn = std::function<std::vector<std::string>(const std::string& name)>;

class EnrTreeResolver
{
public:
    explicit EnrTreeResolver(DnsTxtLookupFn lookup = {}) noexcept;

    [[nodiscard]] static bool is_enr_tree_url(const std::string& value) noexcept;
    [[nodiscard]] static bool parse_url(const std::string& value, EnrTreeUrl& out) noexcept;
    [[nodiscard]] static std::vector<std::string> system_txt_lookup(const std::string& name) noexcept;

    [[nodiscard]] std::vector<std::string> resolve(
        const std::vector<std::string>& urls,
        size_t                          max_records = 128U) const noexcept;

private:
    [[nodiscard]] std::vector<std::string> resolve_url(
        const EnrTreeUrl& url,
        size_t            max_records) const noexcept;
    void resolve_entry(
        const std::string& domain,
        const std::string& label,
        size_t             max_records,
        std::vector<std::string>& out) const noexcept;

    DnsTxtLookupFn lookup_;
};

} // namespace discv5

#endif // EVMRELAY_INCLUDE_DISCV5_ENR_TREE_HPP

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Updated on 2026-06-05 at 17:22:19 -0700