ooni-probe-cli/internal/experiment/webconnectivity/dnscache.go
Simone Basso 3b24b1196d
fix(webconnectivity@v0.5): fetch HTTP only using system-resolver addrs (#935)
While there, change the emoji logger to emit whitespace on info logs. This makes warnings stand out even more.

Closes https://github.com/ooni/probe/issues/2258
2022-09-05 13:33:59 +02:00

58 lines
1.3 KiB
Go

package webconnectivity
import "sync"
// DNSEntry is an entry in the DNS cache.
type DNSEntry struct {
// Addr is the cached address
Addr string
// Flags contains flags
Flags int64
}
const (
// DNSAddrFlagSystemResolver means we discovered this addr using the system resolver.
DNSAddrFlagSystemResolver = 1 << iota
// DNSAddrFlagUDP means we discovered this addr using the UDP resolver.
DNSAddrFlagUDP
// DNSAddrFlagHTTPS means we discovered this addr using the DNS-over-HTTPS resolver.
DNSAddrFlagHTTPS
)
// DNSCache wraps a model.Resolver to provide DNS caching.
//
// The zero value is invalid; please, use NewDNSCache to construct.
type DNSCache struct {
// mu provides mutual exclusion.
mu *sync.Mutex
// values contains already resolved values.
values map[string][]DNSEntry
}
// Get gets values from the cache
func (c *DNSCache) Get(domain string) ([]DNSEntry, bool) {
c.mu.Lock()
values, found := c.values[domain]
c.mu.Unlock()
return values, found
}
// Set inserts into the cache
func (c *DNSCache) Set(domain string, values []DNSEntry) {
c.mu.Lock()
c.values[domain] = values
c.mu.Unlock()
}
// NewDNSCache creates a new DNSCache instance.
func NewDNSCache() *DNSCache {
return &DNSCache{
mu: &sync.Mutex{},
values: map[string][]DNSEntry{},
}
}