dexador

2017-01-24

Dexador

Build Status Coverage Status

Dexador is yet another HTTP client for Common Lisp with neat APIs and connection-pooling.

Warning

This software is still BETA quality. The APIs will be likely to change.

Differences from Drakma

  • Fast, particularly when requesting to the same host (See Benchmark)
  • Neat APIs
  • Signal a condition when HTTP request failed

See also a presentation given at Lisp Meetup #31.

Usage

(dex:get "http://lisp.org/")

(dex:post "https://example.com/login"
          :content '(("name" . "fukamachi") ("password" . "1ispa1ien")))

Posting a form-data

You can specify a form-data at :content in an association list. The data will be sent in application/x-www-form-urlencoded format.

(dex:post "http://example.com/entry/create"
          :content '(("title" . "The Truth About Lisp")
                     ("body" . "In which the truth about lisp is revealed, and some alternatives are enumerated.")))

Auto-detects Multipart

If the association list contains a pathname, the data will be sent as multipart/form-data.

(dex:post "http://example.com/entry/create"
          :content '(("photo" . #P"images/2015030201.jpg")))

Following redirects (GET or HEAD)

If the server reports that the requested page has moved to a different location (indicated with a Location header and a 3XX response code), Dexador will redo the request on the new place, the fourth return value shows.

(dex:head "http://lisp.org")
;=> ""
;   200
;   #<HASH-TABLE :TEST EQUAL :COUNT 7 {100D2A47A3}>
;   #<QURI.URI.HTTP:URI-HTTP http://lisp.org/index.html>
;   NIL

You can limit the count of redirection by specifying :max-redirects with an integer. The default value is 5.

Using cookies

Dexador adopts cl-cookie for its cookie management. All functions takes a cookie-jar instance at :cookie-jar.

(defvar *cookie-jar* (cl-cookie:make-cookie-jar))

(dex:head "https://mixi.jp" :cookie-jar *cookie-jar* :verbose t)
;-> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   HEAD / HTTP/1.1
;   User-Agent: Dexador/0.1 (SBCL 1.2.9); Darwin; 14.1.0
;   Host: mixi.jp
;   Accept: */*
;   
;   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
;   HTTP/1.1 200 OK
;   Date: Tue, 10 Mar 2015 10:16:29 GMT
;   Server: Apache
;   X-Dealer: 152151
;   X-XRDS-Location: https://mixi.jp/xrds.pl
;   Cache-Control: no-cache
;   Pragma: no-cache
;   Vary: User-Agent
;   Content-Type: text/html; charset=EUC-JP
;   Set-Cookie: _auid=9d47ca5a00ce4980c41511beb2626fd4; domain=.mixi.jp; path=/; expires=Thu, 09-Mar-2017 10:16:29 GMT
;   Set-Cookie: _lcp=8ee4121c9866435007fff2c90dc31a4d; domain=.mixi.jp; expires=Wed, 11-Mar-2015 10:16:29 GMT
;   X-Content-Type-Options: nosniff
;   
;   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

;; Again
(dex:head "https://mixi.jp" :cookie-jar *cookie-jar* :verbose t)
;-> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   HEAD / HTTP/1.1
;   User-Agent: Dexador/0.1 (SBCL 1.2.9); Darwin; 14.1.0
;   Host: mixi.jp
;   Accept: */*
;   Cookie: _auid=b878756ed71a0ed5bcf527e324c78f8c; _lcp=8ee4121c9866435007fff2c90dc31a4d
;   
;   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
;   HTTP/1.1 200 OK
;   Date: Tue, 10 Mar 2015 10:16:59 GMT
;   Server: Apache
;   X-Dealer: 152146
;   X-XRDS-Location: https://mixi.jp/xrds.pl
;   Cache-Control: no-cache
;   Pragma: no-cache
;   Vary: User-Agent
;   Content-Type: text/html; charset=EUC-JP
;   Set-Cookie: _auid=b878756ed71a0ed5bcf527e324c78f8c; domain=.mixi.jp; path=/; expires=Thu, 09-Mar-2017 10:16:59 GMT
;   Set-Cookie: _lcp=8ee4121c9866435007fff2c90dc31a4d; domain=.mixi.jp; expires=Wed, 11-Mar-2015 10:16:59 GMT
;   X-Content-Type-Options: nosniff
;   
;   <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

Basic Authorization

(dex:head "http://www.hatena.ne.jp/" :basic-auth '("nitro_idiot" . "password") :verbose t)
;-> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   HEAD / HTTP/1.1
;   User-Agent: Dexador/0.1 (SBCL 1.2.9); Darwin; 14.1.0
;   Host: www.hatena.ne.jp
;   Accept: */*
;   Authorization: Basic bml0cm9faWRpb3Q6cGFzc3dvcmQ=
;   
;   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Faking a User-Agent header

You can overwrite the default User-Agent header by simply specifying "User-Agent" in :headers.

(dex:head "http://www.sbcl.org/" :verbose t)
;-> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   HEAD / HTTP/1.1
;   User-Agent: Dexador/0.1 (SBCL 1.2.6); Darwin; 14.1.0
;   Host: www.sbcl.org
;   Accept: */*
;   
;   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

(dex:head "http://www.sbcl.org/"
          :headers '(("User-Agent" . "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_2) AppleWebKit/600.3.18 (KHTML, like Gecko) Version/8.0.3 Safari/600.3.18"))
          :verbose t)
;-> >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
;   HEAD / HTTP/1.1
;   User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_2) AppleWebKit/600.3.18 (KHTML, like Gecko) Version/8.0.3 Safari/600.3.18
;   Host: www.sbcl.org
;   Accept: */*
;   
;   >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Reusing a connection

Dexador reuses a connection by default. As it skips a TCP handshake, it would be much faster when you send requests to the same host continuously.

Handling unexpected HTTP status code

Dexador singals a condition http-request-failed when the server returned 4xx or 5xx status code.

;; Handles 400 bad request
(handler-case (dex:get "http://lisp.org")
  (dex:http-request-bad-request ()
    ;; Runs when 400 bad request returned
    )
  (dex:http-request-failed (e)
    ;; For other 4xx or 5xx
    (format *error-output* "The server returned ~D" (dex:response-status e))))

;; Ignore 404 Not Found and continue
(handler-bind ((dex:http-request-not-found #'dex:ignore-and-continue))
  (dex:get "http://lisp.org"))

;; Retry
(handler-bind ((dex:http-request-failed #'dex:retry-request))
  (dex:get "http://lisp.org"))

;; Retry 5 times
(handler-bind ((dex:http-request-failed (dex:retry-request 5 :interval 3)))
  (dex:get "http://lisp.org"))

Proxy

You can connect via proxy.

(dex:get "http://lisp.org/" :proxy "http://proxy.yourcompany.com:8080/")

Functions

All functions take similar arguments.

  • uri (string or quri:uri)
  • method (keyword)
  • The HTTP request method: :GET, :HEAD, :OPTIONS, :PUT, :POST, or :DELETE. The default is :GET.
  • version (number)
  • The version of the HTTP protocol: typically 1.0 or 1.1. The default is 1.1.
  • content (string, alist or pathname)
  • The body of the request.
  • headers (alist)
  • The headers of the request. If the value of a pair is NIL, the header won't be sent. You can overwrite the default headers (Host, User-Agent and Accept) by this with the same header name.
  • basic-auth (cons of username and password)
  • Username and password for basic authorization. This is a cons having username at car and password at cdr. (e.g. '("foo" . "bar"))
  • cookie-jar (cookie-jar of cl-cookie)
  • A cookie jar object.
  • timeout (fixnum)
  • The seconds to timeout of the HTTP connection. The default is 10, the value of *default-timeout*.
  • keep-alive (boolean)
  • A flag if the connection keep connected even after the HTTP request. The default is NIL.
  • use-connection-pool (boolean)
  • A flag if use a connection pool.
  • max-redirects (fixnum)
  • The limit of redirections. The default is 5. If the redirection exceeds the limit, functions return the last response (not raise a condition).
  • force-binary (boolean)
  • A flag for suppressing auto-decoding of the response body.
  • want-stream (boolean)
  • A flag to get the response body as a stream.
  • ssl-key-file, ssl-cert-file, ssl-key-password
  • for HTTPS connection
  • stream
  • The stream to write an HTTP request. This is the way to reuse a connection and commonly used with :keep-alive T.
  • verbose (boolean)
  • This option is for debugging. If this is T, it dumps the HTTP request headers.
  • proxy (string)
  • for use proxy.

[Function] request

(dex:request uri &key method version content headers basic-auth cookie-jar timeout
                   (keep-alive t) (use-connection-pool t) (max-redirects 5)
                   ssl-key-file ssl-cert-file ssl-key-password
                   stream verbose force-binary want-stream proxy)
;=> body
;   status
;   response-headers
;   uri
;   stream

Send an HTTP request to uri.

The body is an octet vector or a string if the Content-Type is text/*. If you always want it to return an octet vector, specify :force-binary as T.

The status is an integer which represents HTTP status code.

The response-headers is a hash table which represents HTTP response headers. Note that all hash keys are downcased like "content-type". If there's duplicate HTTP headers, those values are concatenated with a comma.

The uri is a QURI object which represents the last URI Dexador requested.

The stream is a usocket stream to communicate with the HTTP server if the connection is still alive and can be reused. This value may be NIL if :keep-alive is NIL or the server closed the connection with Connection: close header.

This function signals http-request-failed when the HTTP status code is 4xx or 5xx.

[Function] get

(dex:get uri &key version headers basic-auth cookie-jar keep-alive timeout max-redirects force-binary want-stream
               ssl-key-file ssl-cert-file ssl-key-password
               stream verbose proxy)

[Function] post

(dex:post uri &key version headers content cookie-jar keep-alive timeout force-binary want-stream
                ssl-key-file ssl-cert-file ssl-key-password
                stream verbose proxy)

[Function] head

(dex:head uri &key version headers cookie-jar timeout max-redirects
                ssl-key-file ssl-cert-file ssl-key-password
                stream verbose proxy)

[Function] put

(dex:put uri &key version headers content cookie-jar keep-alive timeout force-binary want-stream
               ssl-key-file ssl-cert-file ssl-key-password
               stream verbose proxy)

[Function] delete

(dex:delete uri &key version headers cookie-jar keep-alive timeout force-binary want-stream
                  ssl-key-file ssl-cert-file ssl-key-password
                  stream verbose proxy)

[Function] fetch

Send a GET request to URI and write the response body to the DESTINATION.

(dex:fetch uri destination &key if-exists verbose proxy)

Benchmark

Benchmark graph

Benchmark graph

  • Server
  • Sakura VPS 1GB
  • nginx 1.2.7, KeepAlive On
  • Client
  • MacBook Pro OS X Yosemite (CPU: 3GHz Intel Core i7, Memory: 8GB)
  • SBCL 1.2.9
  • Downloads an HTML file (181 bytes).

Drakma

(time (dotimes (i 30) (drakma:http-request "http://files.8arrow.org/181B.html")))
Evaluation took:
  1.012 seconds of real time
  0.174742 seconds of total run time (0.148141 user, 0.026601 system)
  17.29% CPU
  1,683 forms interpreted
  500 lambdas converted
  3,027,928,949 processor cycles
  29,416,656 bytes consed

Dexador

(time (dotimes (i 30) (dex:get "http://files.8arrow.org/181B.html")))
Evaluation took:
  0.499 seconds of real time
  0.028057 seconds of total run time (0.019234 user, 0.008823 system)
  5.61% CPU
  56 forms interpreted
  16 lambdas converted
  1,494,851,690 processor cycles
  1,472,992 bytes consed

See Also

Author

  • Eitaro Fukamachi (e.arrows@gmail.com)

Copyright (c) 2015 Eitaro Fukamachi (e.arrows@gmail.com)

License

Licensed under the MIT License.

Author
Eitaro Fukamachi
License
MIT
Categories
http client, library