Re: prefetch proxy

[Jim Jagielski]

Here is the method for the Jenkins CLI that causes all the sadness.
The major section is this:

        con.getOutputStream().close();
        input = con.getInputStream();
        // make sure we hit the right URL
        if(con.getHeaderField("Hudson-Duplex")==null)
            throw new IOException(target+" doesn't look like Jenkins");

        // client->server uses chunked encoded POST for unlimited capacity. 
        con = (HttpURLConnection) target.openConnection();
        con.setDoOutput(true); // request POST
        con.setRequestMethod("POST");
        con.setChunkedStreamingMode(0);
        con.setRequestProperty("Content-type","application/octet-stream");
        con.addRequestProperty("Session", uuid.toString());
        con.addRequestProperty("Side","upload");

It is this second POST which causes the 400 error and the prefetch
to bail out...

    public FullDuplexHttpStream(URL target) throws IOException {
        this.target = target;

        String authorization = null;
        if (target.getUserInfo() != null) {
                authorization = new String(new 
Base64().encodeBase64(target.getUserInfo().getBytes()));
        }

        CrumbData crumbData = new CrumbData();

        UUID uuid = UUID.randomUUID(); // so that the server can correlate 
those two connections

        // server->client
        HttpURLConnection con = (HttpURLConnection) target.openConnection();
        con.setDoOutput(true); // request POST to avoid caching
        con.setRequestMethod("POST");
        con.addRequestProperty("Session", uuid.toString());
        con.addRequestProperty("Side","download");
        if (authorization != null) {
            con.addRequestProperty("Authorization", "Basic " + authorization);
        }
        if(crumbData.isValid) {
            con.addRequestProperty(crumbData.crumbName, crumbData.crumb);
        }
        con.getOutputStream().close();
        input = con.getInputStream();
        // make sure we hit the right URL
        if(con.getHeaderField("Hudson-Duplex")==null)
            throw new IOException(target+" doesn't look like Jenkins");

        // client->server uses chunked encoded POST for unlimited capacity. 
        con = (HttpURLConnection) target.openConnection();
        con.setDoOutput(true); // request POST
        con.setRequestMethod("POST");
        con.setChunkedStreamingMode(0);
        con.setRequestProperty("Content-type","application/octet-stream");
        con.addRequestProperty("Session", uuid.toString());
        con.addRequestProperty("Side","upload");
        if (authorization != null) {
                con.addRequestProperty ("Authorization", "Basic " + 
authorization);
        }

        if(crumbData.isValid) {
            con.addRequestProperty(crumbData.crumbName, crumbData.crumb);
        }
        output = con.getOutputStream();
    }