CoopExecutor
in package
implements
ExecutorInterface
Cooperatively resolves hosts via the given base executor to ensure same query is not run concurrently
Wraps an existing ExecutorInterface to keep tracking of pending queries
and only starts a new query when the same query is not already pending. Once
the underlying query is fulfilled/rejected, it will forward its value to all
promises awaiting the same query.
This means it will not limit concurrency for queries that differ, for example when sending many queries for different host names or types.
This is useful because all executors are entirely async and as such allow you to execute any number of queries concurrently. You should probably limit the number of concurrent queries in your application or you're very likely going to face rate limitations and bans on the resolver end. For many common applications, you may want to avoid sending the same query multiple times when the first one is still pending, so you will likely want to use this in combination with some other executor like this:
$executor = new CoopExecutor(
new RetryExecutor(
new TimeoutExecutor(
new UdpTransportExecutor($nameserver),
3.0
)
)
);
Table of Contents
Interfaces
Properties
Methods
- __construct() : mixed
- query() : PromiseInterface<string|int, Message>
- Executes a query and will return a response message
- serializeQueryToIdentity() : mixed
Properties
$counts
private
mixed
$counts
= array()
$executor
private
mixed
$executor
$pending
private
mixed
$pending
= array()
Methods
__construct()
public
__construct(ExecutorInterface $base) : mixed
Parameters
- $base : ExecutorInterface
query()
Executes a query and will return a response message
public
query(Query $query) : PromiseInterface<string|int, Message>
It returns a Promise which either fulfills with a response
React\Dns\Model\Message on success or rejects with an Exception if
the query is not successful. A response message may indicate an error
condition in its rcode, but this is considered a valid response message.
$executor->query($query)->then(
function (React\Dns\Model\Message $response) {
// response message successfully received
var_dump($response->rcode, $response->answers);
},
function (Exception $error) {
// failed to query due to $error
}
);
The returned Promise MUST be implemented in such a way that it can be cancelled when it is still pending. Cancelling a pending promise MUST reject its value with an Exception. It SHOULD clean up any underlying resources and references as applicable.
$promise = $executor->query($query);
$promise->cancel();
Parameters
- $query : Query
Return values
PromiseInterface<string|int, Message> —resolves with response message on success or rejects with an Exception on error
serializeQueryToIdentity()
private
serializeQueryToIdentity(Query $query) : mixed
Parameters
- $query : Query