Manually follow http redirect when needed

[pawoolley]

While trying to run the jenkinsfile-runner from the command line, without the extra -w option to point to a war file, I noticed that the app tried to download the latest jenkins.war but fails because the target url of http://updates.jenkins.io/download/war/2.277.4/jenkins.war redirects across schemes (http -> https) to https://get.jenkins.io/war-stable/2.277.4/jenkins.war. This jump of schemes is not handle automatically by Java's HttpURLConnection and must be dealt with manually.

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[oleg-nenashev]

Looks good. IIUC it will not follow multiple redirects

[pawoolley]

Looks good. IIUC it will not follow multiple redirects

If there were a chain of redirects that went http -> https -> http, then no, this change would not handle that, but it's good enough for the purposes of the http -> https change that happens when downloading the jenkins.war file. And it should be good enough for any redirects that happen where the http(s) scheme remains the same.

[pawoolley]

Btw, @oleg-nenashev, I don't have permissions to merge this now that it has all green ticks. Is that something you do, or someone can give me the permission to do?

[oleg-nenashev]

I will merge it. When do you need a release? This repo does not have CD at the moment?

[pawoolley]

I will merge it. When do you need a release? This repo does not have CD at the moment?

Ah, ok. I don't need a release any time soon. Was just curious as to what the process was.