From 4f5234be0378368e6af25925db46612838d25e58 Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Thu, 21 Nov 2019 20:36:20 +0100 Subject: substitute: Don't fetch /nix-cache-info. This avoids one GET request every time 'fetch-narinfos' is called. The file itself was essentially useless. * guix/scripts/substitute.scm (, download-cache-info): Remove. (%unreachable-hosts): New variable. (open-connection-for-uri/maybe): New procedure. (fetch-narinfos)[handle-narinfo-response]: Check whether NARINFO has its 'path' under (%store-prefix) and ignore it otherwise. Move 'update-progress!' call before 'if'. [do-fetch]: Remove 'port' parameter. Use 'open-connection-for-uri/maybe'. Remove call to 'download-cache-info'. --- guix/scripts/substitute.scm | 142 +++++++++++++++++++------------------------- 1 file changed, 61 insertions(+), 81 deletions(-) (limited to 'guix/scripts/substitute.scm') diff --git a/guix/scripts/substitute.scm b/guix/scripts/substitute.scm index dba08edf50..992b21d505 100755 --- a/guix/scripts/substitute.scm +++ b/guix/scripts/substitute.scm @@ -227,58 +227,6 @@ provide." (leave (G_ "unsupported substitute URI scheme: ~a~%") (uri->string uri))))) -(define-record-type - (%make-cache-info url store-directory wants-mass-query?) - cache-info? - (url cache-info-url) - (store-directory cache-info-store-directory) - (wants-mass-query? cache-info-wants-mass-query?)) - -(define (download-cache-info url) - "Download the information for the cache at URL. On success, return a - object and a port on which to send further HTTP requests. On -failure, return #f and #f." - (define uri - (string->uri (string-append url "/nix-cache-info"))) - - (define (read-cache-info port) - (alist->record (fields->alist port) - (cut %make-cache-info url <...>) - '("StoreDir" "WantMassQuery"))) - - (catch #t - (lambda () - (case (uri-scheme uri) - ((file) - (values (call-with-input-file (uri-path uri) - read-cache-info) - #f)) - ((http https) - (let ((port (guix:open-connection-for-uri - uri - #:verify-certificate? #f - #:timeout %fetch-timeout))) - (guard (c ((http-get-error? c) - (warning (G_ "while fetching '~a': ~a (~s)~%") - (uri->string (http-get-error-uri c)) - (http-get-error-code c) - (http-get-error-reason c)) - (close-connection port) - (warning (G_ "ignoring substitute server at '~s'~%") url) - (values #f #f))) - (values (read-cache-info (http-fetch uri - #:verify-certificate? #f - #:port port - #:keep-alive? #t)) - port)))))) - (lambda (key . args) - (case key - ((getaddrinfo-error system-error) - ;; Silently ignore the error: probably due to lack of network access. - (values #f #f)) - (else - (apply throw key args)))))) - (define-record-type (%make-narinfo path uri-base uris compressions file-sizes file-hashes @@ -628,6 +576,41 @@ if file doesn't exist, and the narinfo otherwise." #f (apply throw args))))) +(define %unreachable-hosts + ;; Set of names of unreachable hosts. + (make-hash-table)) + +(define* (open-connection-for-uri/maybe uri + #:key + (verify-certificate? #f) + (time %fetch-timeout)) + "Open a connection to URI and return a port to it, or, if connection failed, +print a warning and return #f." + (define host + (uri-host uri)) + + (catch #t + (lambda () + (guix:open-connection-for-uri uri + #:verify-certificate? verify-certificate? + #:timeout time)) + (match-lambda* + (('getaddrinfo-error error) + (unless (hash-ref %unreachable-hosts host) + (hash-set! %unreachable-hosts host #t) ;warn only once + (warning (G_ "~a: host not found: ~a~%") + host (gai-strerror error))) + #f) + (('system-error . args) + (unless (hash-ref %unreachable-hosts host) + (hash-set! %unreachable-hosts host #t) + (warning (G_ "~a: connection failed: ~a~%") host + (strerror + (system-error-errno `(system-error ,@args))))) + #f) + (args + (apply throw args))))) + (define (fetch-narinfos url paths) "Retrieve all the narinfos for PATHS from the cache at URL and return them." (define update-progress! @@ -657,13 +640,18 @@ if file doesn't exist, and the narinfo otherwise." (len (response-content-length response)) (cache (response-cache-control response)) (ttl (and cache (assoc-ref cache 'max-age)))) + (update-progress!) + ;; Make sure to read no more than LEN bytes since subsequent bytes may ;; belong to the next response. (if (= code 200) ; hit (let ((narinfo (read-narinfo port url #:size len))) - (cache-narinfo! url (narinfo-path narinfo) narinfo ttl) - (update-progress!) - (cons narinfo result)) + (if (string=? (dirname (narinfo-path narinfo)) + (%store-prefix)) + (begin + (cache-narinfo! url (narinfo-path narinfo) narinfo ttl) + (cons narinfo result)) + result)) (let* ((path (uri-path (request-uri request))) (hash-part (basename (string-drop-right path 8)))) ;drop ".narinfo" @@ -674,26 +662,28 @@ if file doesn't exist, and the narinfo otherwise." (if (= 404 code) ttl %narinfo-transient-error-ttl)) - (update-progress!) result)))) - (define (do-fetch uri port) + (define (do-fetch uri) (case (and=> uri uri-scheme) ((http https) (let ((requests (map (cut narinfo-request url <>) paths))) - (update-progress!) - - ;; Note: Do not check HTTPS server certificates to avoid depending on - ;; the X.509 PKI. We can do it because we authenticate narinfos, - ;; which provides a much stronger guarantee. - (let ((result (http-multiple-get uri - handle-narinfo-response '() - requests - #:verify-certificate? #f - #:port port))) - (close-connection port) - (newline (current-error-port)) - result))) + (match (open-connection-for-uri/maybe uri) + (#f + '()) + (port + (update-progress!) + ;; Note: Do not check HTTPS server certificates to avoid depending + ;; on the X.509 PKI. We can do it because we authenticate + ;; narinfos, which provides a much stronger guarantee. + (let ((result (http-multiple-get uri + handle-narinfo-response '() + requests + #:verify-certificate? #f + #:port port))) + (close-port port) + (newline (current-error-port)) + result))))) ((file #f) (let* ((base (string-append (uri-path uri) "/")) (files (map (compose (cut string-append base <> ".narinfo") @@ -704,17 +694,7 @@ if file doesn't exist, and the narinfo otherwise." (leave (G_ "~s: unsupported server URI scheme~%") (if uri (uri-scheme uri) url))))) - (let-values (((cache-info port) - (download-cache-info url))) - (and cache-info - (if (string=? (cache-info-store-directory cache-info) - (%store-prefix)) - (do-fetch (string->uri url) port) ;reuse PORT - (begin - (warning (G_ "'~a' uses different store '~a'; ignoring it~%") - url (cache-info-store-directory cache-info)) - (close-connection port) - #f))))) + (do-fetch (string->uri url))) (define (lookup-narinfos cache paths) "Return the narinfos for PATHS, invoking the server at CACHE when no -- cgit v1.2.3