REST API for purging tweets (digitalmethodsinitiative#205)

REST API for purging tweets, thanks to @hoylen

analysis/common/functions.php

@@ -4,16 +4,21 @@
 
 db_connect($hostname, $dbuser, $dbpass, $database);
 
+$datasets = get_all_datasets();
+
 // catch parameters
 if (isset($_GET['dataset']) && !empty($_GET['dataset']))
     $dataset = urldecode($_GET['dataset']);
-else {
+else if (count($datasets) != 0) {
+    // Default to earliest created not-deleted query bin
     $sql = "SELECT querybin FROM tcat_query_bins ORDER BY id LIMIT 1";
     $rec = mysql_query($sql);
     if ($res = mysql_fetch_assoc($rec))
         $dataset = $res['querybin'];
+} else {
+    $dataset = NULL; // No query bins exist
 }
-$datasets = get_all_datasets();
+
 if (isset($_GET['query']) && !empty($_GET['query']))
     $query = urldecode($_GET['query']);
 else
@@ -818,6 +823,7 @@ function get_all_datasets() {
     $dbh = pdo_connect();
     $rec = $dbh->prepare("SELECT id, querybin, type, active, comments FROM tcat_query_bins WHERE access = " . TCAT_QUERYBIN_ACCESS_OK . " OR access = " . TCAT_QUERYBIN_ACCESS_READONLY . " ORDER BY LOWER(querybin)");
     $datasets = array();
+    try {
     if ($rec->execute() && $rec->rowCount() > 0) {
         while ($res = $rec->fetch()) {
             $row = array();
@@ -853,6 +859,16 @@ function get_all_datasets() {
             $datasets[$row['bin']] = $row;
         }
     }
+
+    } catch (PDOException $e) {
+        if ($e->errorInfo[0] == '42S02') {
+            // Base table or view not found
+            // Tables not yet created: just return empty $datasets
+        } else {
+            throw $e;
+        }
+    }
+
     return $datasets;
 }
 

api/api.css

@@ -0,0 +1,112 @@
+/* TCAT API */
+
+/* COMMON */
+
+body {
+    font-family: sans-serif;
+    font-size: 12px;
+}
+
+h1 {
+    float: left;
+    margin: 0;
+    padding: 1em 0 1ex 0;
+
+    font-size: 150%;
+}
+h2 { font-size: 130%; }
+h3 { font-size: 115%; }
+
+
+
+/* ids */
+
+#content {
+    max-width: 1000px;
+    padding: 1ex 0 1ex 0;
+}
+
+/* Top links */
+
+#if_links {
+    float: right;
+    margin: 2ex 0 1ex 0;
+}
+
+#if_links a {
+    display: inline-block;
+    margin-left: 1em;
+    text-decoration: none;
+    color: #000;
+}
+#if_links a:before { content: "» "; }
+#if_links a:hover { text-decoration: underline; }
+
+/* Breadcrumb navigation */
+
+ul.breadcrumbs {
+    display: block;
+    clear: both;
+    margin: 0;
+    padding: 1ex 0 1ex 0;
+}
+
+ul.breadcrumbs > li {
+    display: inline-block;
+    color: #999;
+}
+ul.breadcrumbs > li:first-child:before { content: ""; }
+ul.breadcrumbs > li:before { content: " » "; }
+
+ul.breadcrumbs > li > a {
+    display: inline-block;
+    color: #999;
+    text-decoration: none;
+}
+ul.breadcrumbs > li > a:hover {
+    color: #000;
+    text-decoration: underline;
+}
+
+/* Main contents of page */
+
+div#content { clear: both; }
+
+/* Tables */
+
+table {
+    border-collapse: collapse;
+}
+th {
+    padding-right: 0.5em;
+    text-align: right;
+}
+th:after {
+    content: ":";
+}
+td { padding: 0.5ex; }
+
+/* SPECIFIC */
+
+/* Text input fields on querybin tweet view page */
+
+input#startdate, input#enddate {
+    min-width: 16em; /* to accommodate "YYYY-MM-DD HH:MM:SS +hh:mm" */
+}
+#export-tweets-form {
+    float: left;
+    margin-top: 2ex;
+}
+#purge-tweets-form {
+    float: right;
+    margin-top: 2ex;
+    text-align: center;
+}
+
+#purge-time-warning {
+    clear: both;
+    padding: 1ex 0;
+    text-align: right;
+    color: #666;
+}
+/* EOF */

api/index.php

@@ -0,0 +1,24 @@
+<?php
+require_once __DIR__ . '/lib/common.php';
+require_once __DIR__ . '/lib/http_util.php';
+
+switch (choose_mediatype(['text/html'])) {
+    case 'text/html':
+        html_begin("API", []);
+        echo <<<END
+
+            <ul>
+              <li><a href="querybin.php">List query bins</a></li>
+            </ul>
+
+END;
+        echo "<p>Version: ", API_VERSION, "</p>\n";
+        html_end();
+        break;
+    default:
+        echo "DMI-TCAT API (version: ", API_VERSION, ")\n";
+        echo "  Running this script from the command line does nothing useful!\n";
+        echo "  Run \"php querybin.php --help\" instead.\n";
+        exit(1);
+        break;
+}

api/lib/common.php

@@ -0,0 +1,36 @@
+<?php
+// Common code that is loaded by all the API PHP scripts.
+
+define('API_VERSION', '1.0');
+
+// Speed multiplier for estimating purge times.
+//
+// Set this to a number greater than 1.0 for slower machines.
+// Set this to a number less than 1.0 for faster machines.
+
+define('PURGE_TIME_FACTOR', 1.0);
+
+// Default timezone
+//
+// Set this to a string indicating the timezone to use for displaying
+// times and for parsing strings (when no explicit timezone is in the
+// string).
+//
+// Valid values can be found at: <http://php.net/manual/timezones.php>
+//
+// Strings of the form "+HH:MM" DO NOT WORK correctly. if you must
+// specify an offset, try the values under the "Other" section of the
+// above page. Note: those values are incomplete and the sign is
+// reversed (e.g. for UTC+10, the name is "Etc/GMT-10"). PHP!
+//
+// If not set (or set to NULL), times will be displayed in UTC and strings
+// being parsed must explicitly include a timezone.
+//
+// Examples:
+//   $api_timezone = date_default_timezone_get(); // PHP's default
+//   $api_timezone = 'UTC';
+//   $api_timezone = 'Europe/Amsterdam';
+//   $api_timezone = 'Australia/Brisbane';
+
+$api_timezone = NULL;
+