I’ve finally solved a vexing problem that has been affecting version checks for my software.<\/p>\n
Basically, checking for updates inside of XRay<\/a> and Zingg!<\/a> asks my webserver for a .plist file which contains the latest versions of everything, along with a brief message. On the server, however, this is actually a PHP script which also stores the user’s system version – which is appended to the URL – into a small database.<\/p>\n Since I changed over to DreamHost<\/a>, my server has been set to gzip everything it sends if the receiver is capable of decoding gzipped files. However, for some time – not sure when that changed – this has messed up my version checking, and users would get a “website was unreachable” error. I did get some reports about this every couple of months, but always had attributed it to a network glitch somewhere… until I tried it myself and got consistent errors.<\/p>\n I read the .plist file directly using +[NSDictionary dictionaryWithContentsOfURL:]. Some combination of Cocoa, php and server parameters now causes the result to be gzipped, and NSDictionary doesn’t understand that format. Anyway, once I figured it out, I had to find a way to turn gzipping off for this particular file only, as I can’t change all the old software versions that are out there.<\/p>\n So, for now, adding this statement at the front of the php part of the file solved it:<\/p>\n Strangely enough, rfc2616<\/a> says:<\/p>\n The Internet Assigned Numbers Authority (IANA) acts as a registry for content-coding value tokens. Initially, the registry contains the following tokens:<\/p>\n gzip…<\/p>\n compress…<\/p>\n deflate…<\/p>\n identity The default (identity) encoding; the use of no transformation whatsoever. This content-coding is used only in the Accept- Encoding header, and SHOULD NOT be used in the Content-Encoding header.<\/p><\/blockquote>\n …and that’s it. No “UTF-8” is mentioned, so why is it working now? I tried “identity” (before seeing the SHOULD NOT comment) and it had no effect at all. I suppose I should try to debug this on my local server adn see where the problem lies, but time is short…<\/p>\n I don’t plan to use this method in XRay II, so it’s not urgent. I’ll probably use Andy Matuschak<\/a>‘s Sparkle<\/a>, of which I’ve had good references.<\/p>\n","protected":false},"excerpt":{"rendered":" I’ve finally solved a vexing problem that has been affecting version checks for my software. Basically, checking for updates inside of XRay and Zingg! asks my webserver for a .plist file which contains the latest versions of everything, along with a brief message. On the server, however, this is actually a PHP script which also […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4,19],"tags":[29,30],"class_list":["post-1720","post","type-post","status-publish","format-standard","hentry","category-dev","category-software","tag-xray","tag-zingg"],"featured_image_src":null,"author_info":{"display_name":"Rainer Brockerhoff","author_link":"https:\/\/brockerhoff.net\/blog\/author\/rbrockerhoff\/"},"jetpack_featured_media_url":"","jetpack_shortlink":"https:\/\/wp.me\/p1q3Zc-rK","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/posts\/1720","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/comments?post=1720"}],"version-history":[{"count":0,"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/posts\/1720\/revisions"}],"wp:attachment":[{"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/media?parent=1720"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/categories?post=1720"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/brockerhoff.net\/blog\/wp-json\/wp\/v2\/tags?post=1720"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}header('Content-Encoding: UTF-8');<\/code><\/pre>\n