guix-play/guix/scripts/publish.scm
Ludovic Courtès 089b167812
publish: Do not compress already-compressed files.
* guix/scripts/publish.scm (narinfo-string): Force %NO-COMPRESSION when
STORE-PATH matches 'compressed-file?'.
* guix/utils.scm (compressed-file?): New procedure.
* tests/publish.scm ("/*.narinfo for a compressed file"): New test.
2016-08-01 17:58:56 +02:00

590 lines
23 KiB
Scheme
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2015 David Thompson <davet@gnu.org>
;;; Copyright © 2015, 2016 Ludovic Courtès <ludo@gnu.org>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; GNU Guix is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
(define-module (guix scripts publish)
#:use-module ((system repl server) #:prefix repl:)
#:use-module (ice-9 binary-ports)
#:use-module (ice-9 format)
#:use-module (ice-9 match)
#:use-module (ice-9 regex)
#:use-module (rnrs io ports)
#:use-module (rnrs bytevectors)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-2)
#:use-module (srfi srfi-9)
#:use-module (srfi srfi-9 gnu)
#:use-module (srfi srfi-19)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-34)
#:use-module (srfi srfi-37)
#:use-module (web http)
#:use-module (web request)
#:use-module (web response)
#:use-module (web server)
#:use-module (web uri)
#:use-module (guix base32)
#:use-module (guix base64)
#:use-module (guix config)
#:use-module (guix derivations)
#:use-module (guix hash)
#:use-module (guix pki)
#:use-module (guix pk-crypto)
#:use-module (guix store)
#:use-module (guix serialization)
#:use-module (guix zlib)
#:use-module (guix ui)
#:use-module (guix scripts)
#:use-module ((guix utils) #:select (compressed-file?))
#:use-module ((guix build utils) #:select (dump-port))
#:export (guix-publish))
(define (show-help)
(format #t (_ "Usage: guix publish [OPTION]...
Publish ~a over HTTP.\n") %store-directory)
(display (_ "
-p, --port=PORT listen on PORT"))
(display (_ "
--listen=HOST listen on the network interface for HOST"))
(display (_ "
-u, --user=USER change privileges to USER as soon as possible"))
(display (_ "
-C, --compression[=LEVEL]
compress archives at LEVEL"))
(display (_ "
--ttl=TTL announce narinfos can be cached for TTL seconds"))
(display (_ "
-r, --repl[=PORT] spawn REPL server on PORT"))
(newline)
(display (_ "
-h, --help display this help and exit"))
(display (_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
(define (getaddrinfo* host)
"Like 'getaddrinfo', but properly report errors."
(catch 'getaddrinfo-error
(lambda ()
(getaddrinfo host))
(lambda (key error)
(leave (_ "lookup of host '~a' failed: ~a~%")
host (gai-strerror error)))))
;; Nar compression parameters.
(define-record-type <compression>
(compression type level)
compression?
(type compression-type)
(level compression-level))
(define %no-compression
(compression 'none 0))
(define %default-gzip-compression
;; Since we compress on the fly, default to fast compression.
(compression 'gzip 3))
(define %options
(list (option '(#\h "help") #f #f
(lambda _
(show-help)
(exit 0)))
(option '(#\V "version") #f #f
(lambda _
(show-version-and-exit "guix publish")))
(option '(#\u "user") #t #f
(lambda (opt name arg result)
(alist-cons 'user arg result)))
(option '(#\p "port") #t #f
(lambda (opt name arg result)
(alist-cons 'port (string->number* arg) result)))
(option '("listen") #t #f
(lambda (opt name arg result)
(match (getaddrinfo* arg)
((info _ ...)
(alist-cons 'address (addrinfo:addr info)
result))
(()
(leave (_ "lookup of host '~a' returned nothing")
name)))))
(option '(#\C "compression") #f #t
(lambda (opt name arg result)
(match (if arg (string->number* arg) 3)
(0
(alist-cons 'compression %no-compression result))
(level
(if (zlib-available?)
(alist-cons 'compression
(compression 'gzip level)
result)
(begin
(warning (_ "zlib support is missing; \
compression disabled~%"))
result))))))
(option '("ttl") #t #f
(lambda (opt name arg result)
(let ((duration (string->duration arg)))
(unless duration
(leave (_ "~a: invalid duration~%") arg))
(alist-cons 'narinfo-ttl (time-second duration)
result))))
(option '(#\r "repl") #f #t
(lambda (opt name arg result)
;; If port unspecified, use default Guile REPL port.
(let ((port (and arg (string->number* arg))))
(alist-cons 'repl (or port 37146) result))))))
(define %default-options
`((port . 8080)
;; Default to fast & low compression.
(compression . ,(if (zlib-available?)
%default-gzip-compression
%no-compression))
(address . ,(make-socket-address AF_INET INADDR_ANY 0))
(repl . #f)))
(define (lazy-read-file-sexp file)
"Return a promise to read the canonical sexp from FILE."
(delay
(call-with-input-file file
(compose string->canonical-sexp
get-string-all))))
(define %private-key
(lazy-read-file-sexp %private-key-file))
(define %public-key
(lazy-read-file-sexp %public-key-file))
(define %nix-cache-info
`(("StoreDir" . ,%store-directory)
("WantMassQuery" . 0)
("Priority" . 100)))
(define (load-derivation file)
"Read the derivation from FILE."
(call-with-input-file file read-derivation))
(define (signed-string s)
"Sign the hash of the string S with the daemon's key."
(let* ((public-key (force %public-key))
(hash (bytevector->hash-data (sha256 (string->utf8 s))
#:key-type (key-type public-key))))
(signature-sexp hash (force %private-key) public-key)))
(define base64-encode-string
(compose base64-encode string->utf8))
(define* (narinfo-string store store-path key
#:key (compression %no-compression))
"Generate a narinfo key/value string for STORE-PATH; an exception is raised
if STORE-PATH is invalid. Produce a URL that corresponds to COMPRESSION. The
narinfo is signed with KEY."
(let* ((path-info (query-path-info store store-path))
(compression (if (compressed-file? store-path)
%no-compression
compression))
(url (encode-and-join-uri-path
`("nar"
,@(match compression
(($ <compression> 'none)
'())
(($ <compression> type)
(list (symbol->string type))))
,(basename store-path))))
(hash (bytevector->nix-base32-string
(path-info-hash path-info)))
(size (path-info-nar-size path-info))
(references (string-join
(map basename (path-info-references path-info))
" "))
(deriver (path-info-deriver path-info))
(base-info (format #f
"\
StorePath: ~a
URL: ~a
Compression: ~a
NarHash: sha256:~a
NarSize: ~d
References: ~a~%"
store-path url
(compression-type compression)
hash size references))
;; Do not render a "Deriver" or "System" line if we are rendering
;; info for a derivation.
(info (if (not deriver)
base-info
(catch 'system-error
(lambda ()
(let ((drv (load-derivation deriver)))
(format #f "~aSystem: ~a~%Deriver: ~a~%"
base-info (derivation-system drv)
(basename deriver))))
(lambda args
;; DERIVER might be missing, but that's fine:
;; it's only used for <substitutable> where it's
;; optional. 'System' is currently unused.
(if (= ENOENT (system-error-errno args))
base-info
(apply throw args))))))
(signature (base64-encode-string
(canonical-sexp->string (signed-string info)))))
(format #f "~aSignature: 1;~a;~a~%" info (gethostname) signature)))
(define (not-found request)
"Render 404 response for REQUEST."
(values (build-response #:code 404)
(string-append "Resource not found: "
(uri-path (request-uri request)))))
(define (render-nix-cache-info)
"Render server information."
(values '((content-type . (text/plain)))
(lambda (port)
(for-each (match-lambda
((key . value)
(format port "~a: ~a~%" key value)))
%nix-cache-info))))
(define* (render-narinfo store request hash
#:key ttl (compression %no-compression))
"Render metadata for the store path corresponding to HASH. If TTL is true,
advertise it as the maximum validity period (in seconds) via the
'Cache-Control' header. This allows 'guix substitute' to cache it for an
appropriate duration."
(let ((store-path (hash-part->path store hash)))
(if (string-null? store-path)
(not-found request)
(values `((content-type . (application/x-nix-narinfo))
,@(if ttl
`((cache-control (max-age . ,ttl)))
'()))
(cut display
(narinfo-string store store-path (force %private-key)
#:compression compression)
<>)))))
;; XXX: Declare the 'Guix-Compression' HTTP header, which is in fact for
;; internal consumption: it allows us to pass the compression info to
;; 'http-write', as part of the workaround to <http://bugs.gnu.org/21093>.
(declare-header! "Guix-Nar-Compression"
(lambda (str)
(match (call-with-input-string str read)
(('compression type level)
(compression type level))))
compression?
(lambda (compression port)
(match compression
(($ <compression> type level)
(write `(compression ,type ,level) port)))))
(define* (render-nar store request store-item
#:key (compression %no-compression))
"Render archive of the store path corresponding to STORE-ITEM."
(let ((store-path (string-append %store-directory "/" store-item)))
;; The ISO-8859-1 charset *must* be used otherwise HTTP clients will
;; interpret the byte stream as UTF-8 and arbitrarily change invalid byte
;; sequences.
(if (valid-path? store store-path)
(values `((content-type . (application/x-nix-archive
(charset . "ISO-8859-1")))
(guix-nar-compression . ,compression))
;; XXX: We're not returning the actual contents, deferring
;; instead to 'http-write'. This is a hack to work around
;; <http://bugs.gnu.org/21093>.
store-path)
(not-found request))))
(define (render-content-addressed-file store request
name algo hash)
"Return the content of the result of the fixed-output derivation NAME that
has the given HASH of type ALGO."
;; TODO: Support other hash algorithms.
(if (and (eq? algo 'sha256) (= 32 (bytevector-length hash)))
(let ((item (fixed-output-path name hash
#:hash-algo algo
#:recursive? #f)))
(if (valid-path? store item)
(values `((content-type . (application/octet-stream
(charset . "ISO-8859-1"))))
;; XXX: We're not returning the actual contents, deferring
;; instead to 'http-write'. This is a hack to work around
;; <http://bugs.gnu.org/21093>.
item)
(not-found request)))
(not-found request)))
(define extract-narinfo-hash
(let ((regexp (make-regexp "^([a-df-np-sv-z0-9]{32}).narinfo$")))
(lambda (str)
"Return the hash within the narinfo resource string STR, or false if STR
is invalid."
(and=> (regexp-exec regexp str)
(cut match:substring <> 1)))))
(define (get-request? request)
"Return #t if REQUEST uses the GET method."
(eq? (request-method request) 'GET))
(define (request-path-components request)
"Split the URI path of REQUEST into a list of component strings. For
example: \"/foo/bar\" yields '(\"foo\" \"bar\")."
(split-and-decode-uri-path (uri-path (request-uri request))))
;;;
;;; Server.
;;;
(define %http-write
(@@ (web server http) http-write))
(define (sans-content-length response)
"Return RESPONSE without its 'content-length' header."
(set-field response (response-headers)
(alist-delete 'content-length
(response-headers response)
eq?)))
(define-syntax-rule (swallow-EPIPE exp ...)
"Swallow EPIPE errors raised by EXP..."
(catch 'system-error
(lambda ()
exp ...)
(lambda args
(if (= EPIPE (system-error-errno args))
(values)
(apply throw args)))))
(define-syntax-rule (swallow-zlib-error exp ...)
"Swallow 'zlib-error' exceptions raised by EXP..."
(catch 'zlib-error
(lambda ()
exp ...)
(const #f)))
(define (nar-response-port response)
"Return a port on which to write the body of RESPONSE, the response of a
/nar request, according to COMPRESSION."
(match (assoc-ref (response-headers response) 'guix-nar-compression)
(($ <compression> 'gzip level)
;; Note: We cannot used chunked encoding here because
;; 'make-gzip-output-port' wants a file port.
(make-gzip-output-port (response-port response)
#:level level
#:buffer-size (* 64 1024)))
(($ <compression> 'none)
(response-port response))
(#f
(response-port response))))
(define (http-write server client response body)
"Write RESPONSE and BODY to CLIENT, possibly in a separate thread to avoid
blocking."
(match (response-content-type response)
(('application/x-nix-archive . _)
;; Sending the the whole archive can take time so do it in a separate
;; thread so that the main thread can keep working in the meantime.
(call-with-new-thread
(lambda ()
(let* ((response (write-response (sans-content-length response)
client))
(port (begin
(force-output client)
(nar-response-port response))))
;; XXX: Given our ugly workaround for <http://bugs.gnu.org/21093> in
;; 'render-nar', BODY here is just the file name of the store item.
;; We call 'write-file' from here because we know that's the only
;; way to avoid building the whole nar in memory, which could
;; quickly become a real problem. As a bonus, we even do
;; sendfile(2) directly from the store files to the socket.
(swallow-zlib-error
(swallow-EPIPE
(write-file (utf8->string body) port)))
(swallow-zlib-error
(close-port port))
(values)))))
(('application/octet-stream . _)
;; Send a raw file in a separate thread.
(call-with-new-thread
(lambda ()
(catch 'system-error
(lambda ()
(call-with-input-file (utf8->string body)
(lambda (input)
(let* ((size (stat:size (stat input)))
(headers (alist-cons 'content-length size
(alist-delete 'content-length
(response-headers response)
eq?)))
(response (write-response (set-field response
(response-headers)
headers)
client))
(output (response-port response)))
(dump-port input output)
(close-port output)
(values)))))
(lambda args
;; If the file was GC'd behind our back, that's fine. Likewise if
;; the client closes the connection.
(unless (memv (system-error-errno args)
(list ENOENT EPIPE ECONNRESET))
(apply throw args))
(values))))))
(_
;; Handle other responses sequentially.
(%http-write server client response body))))
(define-server-impl concurrent-http-server
;; A variant of Guile's built-in HTTP server that offloads possibly long
;; responses to a different thread.
(@@ (web server http) http-open)
(@@ (web server http) http-read)
http-write
(@@ (web server http) http-close))
(define* (make-request-handler store
#:key
narinfo-ttl
(compression %no-compression))
(lambda (request body)
(format #t "~a ~a~%"
(request-method request)
(uri-path (request-uri request)))
(if (get-request? request) ;reject POST, PUT, etc.
(match (request-path-components request)
;; /nix-cache-info
(("nix-cache-info")
(render-nix-cache-info))
;; /<hash>.narinfo
(((= extract-narinfo-hash (? string? hash)))
;; TODO: Register roots for HASH that will somehow remain for
;; NARINFO-TTL.
(render-narinfo store request hash
#:ttl narinfo-ttl
#:compression compression))
;; Use different URLs depending on the compression type. This
;; guarantees that /nar URLs remain valid even when 'guix publish'
;; is restarted with different compression parameters.
;; /nar/<store-item>
(("nar" store-item)
(render-nar store request store-item
#:compression %no-compression))
;; /nar/gzip/<store-item>
(("nar" "gzip" store-item)
(if (zlib-available?)
(render-nar store request store-item
#:compression
(match compression
(($ <compression> 'gzip)
compression)
(_
%default-gzip-compression)))
(not-found request)))
;; /nar/file/NAME/sha256/HASH
(("file" name "sha256" hash)
(guard (c ((invalid-base32-character? c)
(not-found request)))
(let ((hash (nix-base32-string->bytevector hash)))
(render-content-addressed-file store request
name 'sha256 hash))))
(_ (not-found request)))
(not-found request))))
(define* (run-publish-server socket store
#:key (compression %no-compression) narinfo-ttl)
(run-server (make-request-handler store
#:narinfo-ttl narinfo-ttl
#:compression compression)
concurrent-http-server
`(#:socket ,socket)))
(define (open-server-socket address)
"Return a TCP socket bound to ADDRESS, a socket address."
(let ((sock (socket (sockaddr:fam address) SOCK_STREAM 0)))
(setsockopt sock SOL_SOCKET SO_REUSEADDR 1)
(bind sock address)
sock))
(define (gather-user-privileges user)
"Switch to the identity of USER, a user name."
(catch 'misc-error
(lambda ()
(let ((user (getpw user)))
(setgroups #())
(setgid (passwd:gid user))
(setuid (passwd:uid user))))
(lambda (key proc message args . rest)
(leave (_ "user '~a' not found: ~a~%")
user (apply format #f message args)))))
;;;
;;; Entry point.
;;;
(define (guix-publish . args)
(with-error-handling
(let* ((opts (args-fold* args %options
(lambda (opt name arg result)
(leave (_ "~A: unrecognized option~%") name))
(lambda (arg result)
(leave (_ "~A: extraneous argument~%") arg))
%default-options))
(user (assoc-ref opts 'user))
(port (assoc-ref opts 'port))
(ttl (assoc-ref opts 'narinfo-ttl))
(compression (assoc-ref opts 'compression))
(address (let ((addr (assoc-ref opts 'address)))
(make-socket-address (sockaddr:fam addr)
(sockaddr:addr addr)
port)))
(socket (open-server-socket address))
(repl-port (assoc-ref opts 'repl)))
;; Read the key right away so that (1) we fail early on if we can't
;; access them, and (2) we can then drop privileges.
(force %private-key)
(force %public-key)
(when user
;; Now that we've read the key material and opened the socket, we can
;; drop privileges.
(gather-user-privileges user))
(when (zero? (getuid))
(warning (_ "server running as root; \
consider using the '--user' option!~%")))
(format #t (_ "publishing ~a on ~a, port ~d~%")
%store-directory
(inet-ntop (sockaddr:fam address) (sockaddr:addr address))
(sockaddr:port address))
(when repl-port
(repl:spawn-server (repl:make-tcp-server-socket #:port repl-port)))
(with-store store
(run-publish-server socket store
#:compression compression
#:narinfo-ttl ttl)))))