Java HTTP Client is retrying POST requests on its own after 5 minutes

[Don-vip]

Just discovered ​this:

If a misbehaving remote host doesn't reply to a HTTP POST request within 5 minutes then HTTPClient will silently retry the POST. POST is non-idempotent, but in order to maintain backwards compatibility the sun.net.http.retryPost property was introduced, with a default value of "true": ​javabug:6382788

Indeed:
​https://github.com/unofficial-openjdk/openjdk/blob/2357b5fc925a96e53e6e9a84230be327424ad1ce/src/java.base/share/classes/sun/net/www/http/HttpClient.java#L167

String retryPost = props.getProperty("sun.net.http.retryPost");
if (retryPost != null) {
    retryPostProp = Boolean.parseBoolean(retryPost);
} else {
    retryPostProp = true;
}

We use POST for API diff upload and should make sure to disable this parameter to avoid an unwanted automatic retry.

[Don-vip]

In 15222/josm:

fix #17882 - Disable automatic HTTP POST retry after 5 minutes, see ​https://bugs.openjdk.java.net/browse/JDK-6382788