WARNING: DEPRECATED

I don’t use this anymore, and don’t plan on maintaining it. Please use at your own risk.

HTTP(S) client for PicoLisp

 

This library can be used to make HTTP and HTTPS requests in PicoLisp, with support for authentication.

Please read EXPLAIN.md to learn more about PicoLisp and this HTTPS library.

1. Requirements
2. Getting Started
3. Usage
4. Examples
5. Testing
6. Alternatives
7. Contributing
8. License

Requirements

• PicoLisp 64-bit v3.1.9+
• Tested up to PicoLisp v16.12
• Git
• UNIX/Linux development/build tools (gcc, make/gmake, etc..)
• OpenSSL

Getting Started

These FFI bindings require the Neon C library, compiled as a shared library.

1. Type make to pull and compile the Neon C Library.
2. Include https.l in your project (it loads ffi.l and internal.l).
3. Try the examples below

Linking and Paths

Once compiled, the shared library is symlinked as:

.lib/libneon.so -> .modules/neon/HEAD/src/.libs/libneon.so

The https.l file searches for .lib/libneon.so, relative to its current directory.

Updating

To keep everything updated, type:

git pull && make clean && make

Usage

Only the following functions are exported publicly, and namespaced with (symbols 'https) (or the prefix: https~):

• (uriparse Url) parses a sanitized URL into its separate parts
  • Url String: a URL string to be parsed (does not encode the URL)
• (req-get Url Headers Filename) performs an HTTP GET request
  • Url String: a URL string to make the HTTP request
  • Headers List (optional): a PicoLisp list of cons pairs containing HTTP headers
  • Filename String or Flag (optional): can be a full path to a filename to store the HTTP Body content, the flag T to generate a random filename and store in a tmp dir (~/.pil/tmp), or NIL to return the Body in the Response list
• (req-head Url Headers) performs an HTTP HEAD request
  • Url String: a URL string to make the HTTP request
  • Headers List (optional): a PicoLisp list of cons pairs containing HTTP headers
• (req-post Url Headers Filename Body) performs an HTTP POST request
  • Url String: a URL string to make the HTTP request
  • Headers List (optional): a PicoLisp list of cons pairs containing HTTP headers
  • Filename String or Flag (optional): can be a full path to a filename to store the HTTP Body content, the flag T to generate a random filename and store in a tmp dir (~/.pil/tmp), or NIL to return the Body in the Response list
  • Body String (optional): a string to be sent as part of the HTTP body. Make sure to set the proper Content-Type headers.
• (req-put Url Headers Filename Body): performs an idempotent HTTP PUT request (same as POST).
• (req-delete Url Headers Filename): performs an HTTP DELETE request
  • Url String: a URL string to make the HTTP request
  • Headers List (optional): a PicoLisp list of cons pairs containing HTTP headers
  • Filename String or Flag (optional): can be a full path to a filename to store the HTTP Body content, the flag T to generate a random filename and store in a tmp dir (~/.pil/tmp), or NIL to return the Body in the Response list
• (req Method Url Headers Filename Body): performs an HTTP requeste using the Method you provide. The arguments to req are the same as the convenience methods list above.

Note: These functions are not namespace local symbols, which means they would redefine symbols with the same name in the 'pico namespace

Notes

• A successful result will return a list. Failures return NIL or throw an 'InternalError.
• Arguments are not sanitized, validated, encoded or cleaned in any way. It’s up to you to perform those tasks before sending data to the public functions.
• Only three default headers are sent on each request. They can be overwritten to suit your needs:
  • Accept: */*
  • Accept-Charset: utf/8
  • User-Agent: picolisp-https
• The Host header and HTTP/1.1 strings are sent automatically by the native C library.

• Many authorization schemes are supported, but only Auth-Basic and Auth-Digest have been tested successfully. See more here.

Examples

(uriparse Url)

pil +

(load "https.l")

(symbols 'https)
(uriparse "http://user:pass@test.url:443/test/file.txt?question=answer#section")

-> ("http" "test.url" "user:pass" 443 "/test/file.txt" "question=answer" "section")

Error: (req-get Url Headers Filename)

Mistakes happen, and we’ve added a facility to catch errors when they do occur. Simply (catch 'InternalError and do what you want with it.

pil +

(load "https.l")

(symbols 'https)
(println
  (catch 'InternalError
    (req-get "https://test.url" NIL NIL) ) )

-> (HttpsError . "Could not resolve hostname `test.url': Host not found")

(req-get Url Headers Filename)

In this example, we try to fetch from a URL that doesn’t exist, and receive a response body stored in a temporary file, status code, headers, and other useful information.

pil +

(load "https.l")

(symbols 'https)
(pretty
  (req-get
    "https://google.com/404"
    '(("Referer" . "http://test.url") ("User-Agent" . "picolisp-https-example"))
    T ) )

-> ((("Filename" . "/home/aw/.pil/tmp/2363/dl-7d702f36-1.tmp") ("Filesize" . 1428))
   ("Version" . "HTTP/1.1")
   ("Code" . 404)
   ("Message" . "Not Found")
   ("Url" . "https://google.com/404")
   ("Headers" ("date" . "Mon, 16 Mar 2015 10:50:07 GMT") ("content-length" . "1428") ("server" . "GFE/2.0") ("content-type" . "text/html; charset=UTF-8")) )

(req-get Url Headers NIL)

Here we try to fetch from a URL which does exist, and receive the response body output.

pil +

(load "https.l")

(symbols 'https)
(pretty
  (req-get "http://software-lab.de/donate.html" NIL) )

-> (("Body" . "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN\" \"http://www.w3.org/TR/1998/REC-html40-19980424/loose.dtd\">^J<html lang=\"en\">^J<head>
^J<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\">^J<title>Donate to PicoLisp</title>^J<link rel=\"stylesheet\" href=\"doc/doc.css\" type=\"t
ext/css\">^J</head>^J<body bgcolor=\"#F0F8FF\">^J^J<div style=\"margin-top: 60px; text-align: center;\">^J   <h2>Donate to <a href=\"http://home.picolisp.com\">Pico
Lisp</a></h2>^J^J   If you want to support the development and maintenance of PicoLisp,<br>^J   you can donate <a href=\"http://bitcoin.org\">Bitcoins</a> to the ad
dress<br>^J   <br>^J   <strong>18hPeB7sEtwMvRVrBMmwhJ3hkFzFda2QHN</strong><br>^J   <br>^J   Please send a note to<br>^J   <strong>btc&lt;at&gt;software-lab.de</stro
ng><br>^J   if you like your name to be mentioned.<br>^J   <br>^J   Thank you for your support!^J</div>^J^J<div style=\"margin-top: 60px; text-align: center;\">^J  
 <h3>Thanks to all Donors:</h3>^J   Jon Kleiser<br>^J   Heow Goodman<br>^J</div>^J^J</body>^J</html>^J")
   ("Version" . "HTTP/1.1")
   ("Code" . 200)
   ("Message" . "OK")
   ("Url" . "http://software-lab.de/donate.html")
   ("Headers"
      ("last-modified" . "Thu, 30 Oct 2014 12:25:01 GMT")
      ("date" . "Mon, 16 Mar 2015 10:56:37 GMT")
      ("keep-alive" . "timeout=3, max=100")
      ("content-length" . "1016")
      ("connection" . "Keep-Alive")
      ("accept-ranges" . "bytes")
      ("etag" . "\"757d8-3f8-506a2f824b149\"")
      ("server" . "Apache/2.2.29 (Unix)")
      ("content-type" . "text/html") ) )

(req-head Url Headers)

An HTTP HEAD request never returns a body. You can see it in the result, the Body item has no cdr.

pil +

(load "https.l")

(symbols 'https)
(pretty (req-head "http://software-lab.de/COPYING" NIL))

-> (("Body")
   ("Version" . "HTTP/1.1")
   ("Code" . 200)
   ("Message" . "OK")
   ("Url" . "http://software-lab.de/COPYING")
   ("Headers"
      ("last-modified" . "Mon, 16 Mar 2015 08:40:12 GMT")
      ("date" . "Mon, 16 Mar 2015 10:57:57 GMT")
      ("keep-alive" . "timeout=3, max=100")
      ("content-length" . "1078")
      ("connection" . "Keep-Alive")
      ("accept-ranges" . "bytes")
      ("etag" . "\"4ba06-436-51163cc69f4fd\"")
      ("server" . "Apache/2.2.29 (Unix)")
      ("content-type" . "text/plain") ) )

(req-post Url Headers Filename Body)

Here we send an HTTP POST request with a JSON string (body), and receive the ok response body, along with some headers.

pil +

(load "https.l")

(symbols 'https)
(pretty
  (req-post
    "http://requestb.in/10l0pw01"
    '(("Content-Type" . "application/json"))
    NIL
    "{\"Hello\":\"World\"}" ) )

-> (("Body" . "ok")
   ("Version" . "HTTP/1.1")
   ("Code" . 200)
   ("Message" . "OK")
   ("Url" . "http://requestb.in/10l0pw01")
   ("Headers"
      ("via" . "1.1 vegur")
      ("date" . "Mon, 16 Mar 2015 11:04:05 GMT")
      ("content-length" . "2")
      ("connection" . "keep-alive")
      ("server" . "gunicorn/18.0")
      ("sponsored-by" . "https://www.runscope.com")
      ("content-type" . "text/html; charset=utf-8") ) )

(req-put) / (req-delete)

Pretty much the same as above.

(req Method Url Headers Filename Body)

In this example, we send a request with a custom HTTP method.

pil +

(load "https.l")

(symbols 'https)
(pretty (req "PICO" "https://encrypted.google.com/search?hl=en&q=recursion"))

-> (("Body" . "<!DOCTYPE html>^J<html lang=en>^J  <meta charset=utf-8>^J  <meta name=viewport content=\"initial-scale=1, minimum-scale=1, width=device-width\">^J  <tit
le>Error 405 (Method Not Allowed)!!1</title>^J  <style>^J    *{margin:0;padding:0}html,code{font:15px/22px arial,sans-serif}html{background:#fff;color:#222;padding:
15px}body{margin:7% auto 0;max-width:390px;min-height:180px;padding:30px 0 15px}* > body{background:url(//www.google.com/images/errors/robot.png) 100% 5px no-repeat
;padding-right:205px}p{margin:11px 0 22px;overflow:hidden}ins{color:#777;text-decoration:none}a img{border:0}@media screen and (max-width:772px){body{background:non
e;margin-top:0;max-width:none;padding-right:0}}#logo{background:url(//www.google.com/images/errors/logo_sm_2.png) no-repeat}@media only screen and (min-resolution:1
92dpi){#logo{background:url(//www.google.com/images/errors/logo_sm_2_hr.png) no-repeat 0% 0%/100% 100%;-moz-border-image:url(//www.google.com/images/errors/logo_sm_
2_hr.png) 0}}@media only screen and (-webkit-min-device-pixel-ratio:2){#logo{background:url(//www.google.com/images/errors/logo_sm_2_hr.png) no-repeat;-webkit-backg
round-size:100% 100%}}#logo{display:inline-block;height:55px;width:150px}^J  </style>^J  <a href=//www.google.com/><span id=logo aria-label=Google></span></a>^J  <p
><b>405.</b> <ins>Thatâs an error.</ins>^J  <p>The request method <code>PICO</code> is inappropriate for the URL <code>/search</code>.  <ins>Thatâs all we know.</in
s>^J")
   ("Version" . "HTTP/1.1")
   ("Code" . 405)
   ("Message" . "Method Not Allowed")
   ("Url" . "https://encrypted.google.com/search?hl=en&q=recursion")
   ("Headers" ("date" . "Mon, 16 Mar 2015 11:09:29 GMT") ("content-length" . "1459") ("alternate-protocol" . "443:quic,p=0.5") ("server" . "GFE/2.0") ("content-type
" . "text/html; charset=UTF-8")) )

Testing

This library now comes with full unit tests. To run the tests, type:

make check

Alternatives

The following are alternatives written in pure PicoLisp. They are limited by pipe/read syscalls and shell exec commands.

• HTTP request on Rosetta Code.
• HTTPS request on Rosetta Code.

Contributing

If you find any bugs or issues, please create an issue.

If you want to improve this library, please make a pull-request.

License

MIT License

Copyright (c) 2015 Alexander Williams, Unscramble license@unscramble.jp