www.webdeveloper.com
Results 1 to 5 of 5

Thread: Cannot get data from REST URL

  1. #1
    Join Date
    Sep 2010
    Posts
    3

    Cannot get data from REST URL

    I thought this would be easy. The United States Geological Survey (USGS) now has a way of getting stream flow data from a REST URL. There are different parameters that can be passed, based on which river gauge is desired, which parameter (ie: water temp, water level), and how many days requested. Below is one such URL:

    http://waterservices.usgs.gov/WOF/In...060&period=P1D

    If you access this URL directly in a browser, you get XML data. I thought this would be easy to get through some simple Javascript. Here is my code:

    Code:
    var xmlhttp = null;
    if (window.XMLHttpRequest) {
      xmlhttp = new XMLHttpRequest();
      if ( typeof xmlhttp.overrideMimeType != 'undefined') {
        xmlhttp.overrideMimeType('text/xml');
      }
    } else if (window.ActiveXObject) {
      xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
    } else {
      alert('Perhaps your browser does not support xmlhttprequests?');
    }
    url="http://waterservices.usgs.gov/WOF/InstantaneousValues?location=06306300&variable=00060&period=P1D";
    xmlhttp.open('GET', url, false);
    xmlhttp.send(null);
    xmlhttp.onreadystatechange = function() {
      if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
        // do something with the results
        alert("4 or 200");
      } else {
        // wait for the call to complete
         alert("NOT 4 or 200");
      }
    };
    
    var myObj = eval ( xmlhttp.responseText );
    I'm using Firefox/Firebug. I step through the code and see that I'm getting a "301" error. I never saw this before. I looked it up and find that it is:

    301 Moved Permanently
    The full error in Firebug:

    uncaught exception: [Exception... "Component returned failure code: 0x80004005 (NS_ERROR_FAILURE) [nsIXMLHttpRequest.send]" nsresult: "0x80004005 (NS_ERROR_FAILURE)" location: "JS frame :: http://localhost:8080/RiverStatuses/js/index.js :: anonymous :: line 64" data: no]
    So, I'm confused.

    I also tried dojox's window.name method. That was an adventure. I did what the example told me to do...assigning the call to "deferred". I did get the return XML, but the only way I could see it was to assign it to a DIV. I found no way to assign it to a variable for later processing.

    Thanks for any advice/help!

    Ed

  2. #2
    Join Date
    Sep 2010
    Posts
    3
    Wow, no one?

  3. #3
    Join Date
    Apr 2003
    Location
    Netherlands
    Posts
    21,654
    Try loading to your server first
    Code:
    <?php
    $url="http://waterservices.usgs.gov/WOF/InstantaneousValues?location=06306300&variable=00060&period=P1D";
    $data = file_get_contents($url);
    $file= fopen("myFile.xml", "w");
    fwrite($file, $data);
    fclose($file);
    ?>
    At least 98% of internet users' DNA is identical to that of chimpanzees

  4. #4
    Join Date
    Sep 2010
    Posts
    3
    Thanks for the reply.

    So, I can't do it strictly in Javascript? ..and process the return w/o writing it to a file?

  5. #5
    Join Date
    Apr 2003
    Location
    Netherlands
    Posts
    21,654
    It does appear to be blocked to the open method.
    At least 98% of internet users' DNA is identical to that of chimpanzees

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
HTML5 Development Center

"

"

X vBulletin 4.2.2 Debug Information

  • Page Generation 0.44348 seconds
  • Memory Usage 2,877KB
  • Queries Executed 15 (?)
More Information
Template Usage (34):
  • (1)SHOWTHREAD
  • (1)ad_footer_end
  • (1)ad_footer_start
  • (1)ad_global_above_footer
  • (1)ad_global_below_navbar
  • (1)ad_global_header1
  • (1)ad_global_header2
  • (1)ad_navbar_below
  • (1)ad_showthread_firstpost_sig
  • (1)ad_showthread_firstpost_start
  • (1)ad_thread_first_post_content
  • (1)ad_thread_last_post_content
  • (2)bbcode_code
  • (2)bbcode_quote
  • (1)footer
  • (1)forumjump
  • (1)forumrules
  • (1)gobutton
  • (1)header
  • (1)headinclude
  • (1)headinclude_bottom
  • (5)memberaction_dropdown
  • (1)navbar
  • (4)navbar_link
  • (1)navbar_moderation
  • (1)navbar_noticebit
  • (1)navbar_tabs
  • (2)option
  • (5)postbit
  • (5)postbit_onlinestatus
  • (5)postbit_wrapper
  • (1)spacer_close
  • (1)spacer_open
  • (1)tagbit_wrapper 

Phrase Groups Available (6):
  • global
  • inlinemod
  • postbit
  • posting
  • reputationlevel
  • showthread
Included Files (26):
  • ./showthread.php
  • ./global.php
  • ./includes/class_bootstrap.php
  • ./includes/init.php
  • ./includes/class_core.php
  • ./includes/config.php
  • ./includes/functions.php
  • ./includes/functions_navigation.php
  • ./includes/class_friendly_url.php
  • ./includes/class_hook.php
  • ./includes/class_bootstrap_framework.php
  • ./vb/vb.php
  • ./vb/phrase.php
  • ./includes/functions_facebook.php
  • ./includes/functions_calendar.php
  • ./includes/functions_bigthree.php
  • ./includes/class_postbit.php
  • ./includes/class_bbcode.php
  • ./includes/functions_reputation.php
  • ./includes/functions_notice.php
  • ./packages/vbattach/attach.php
  • ./vb/types.php
  • ./vb/cache.php
  • ./vb/cache/db.php
  • ./vb/cache/observer/db.php
  • ./vb/cache/observer.php 

Hooks Called (70):
  • init_startup
  • friendlyurl_resolve_class
  • init_startup_session_setup_start
  • database_pre_fetch_array
  • database_post_fetch_array
  • init_startup_session_setup_complete
  • global_bootstrap_init_start
  • global_bootstrap_init_complete
  • cache_permissions
  • fetch_threadinfo_query
  • fetch_threadinfo
  • fetch_foruminfo
  • load_show_variables
  • load_forum_show_variables
  • global_state_check
  • global_bootstrap_complete
  • global_start
  • style_fetch
  • global_setup_complete
  • showthread_start
  • showthread_getinfo
  • strip_bbcode
  • friendlyurl_clean_fragment
  • friendlyurl_geturl
  • forumjump
  • cache_templates
  • cache_templates_process
  • template_register_var
  • template_render_output
  • fetch_template_start
  • fetch_template_complete
  • parse_templates
  • fetch_musername
  • notices_check_start
  • notices_noticebit
  • process_templates_complete
  • friendlyurl_redirect_canonical
  • showthread_post_start
  • showthread_query_postids
  • showthread_query
  • bbcode_fetch_tags
  • bbcode_create
  • showthread_postbit_create
  • postbit_factory
  • postbit_display_start
  • postbit_imicons
  • bbcode_parse_start
  • bbcode_parse_complete_precache
  • bbcode_parse_complete
  • postbit_display_complete
  • memberaction_dropdown
  • tag_fetchbit_complete
  • forumrules
  • navbits
  • navbits_complete
  • build_navigation_data
  • build_navigation_array
  • check_navigation_permission
  • process_navigation_links_start
  • process_navigation_links_complete
  • set_navigation_menu_element
  • build_navigation_menudata
  • build_navigation_listdata
  • build_navigation_list
  • set_navigation_tab_main
  • set_navigation_tab_fallback
  • navigation_tab_complete
  • fb_like_button
  • showthread_complete
  • page_templates