resource = new TripalWebServiceResource($base_path); // Intialize the private members variables. $this->path = array(); $this->params = array(); $this->base_path = $base_path; $this->documentation = array(); $this->addDocClass(array( "id" => "http://www.w3.org/ns/hydra/core#Resource", "term" => 'hydra:Resource', "title" => "Resource", 'subClassOf' => NULL, )); } // -------------------------------------------------------------------------- // OVERRIDEABLE FUNCTIONS // -------------------------------------------------------------------------- /** * Responds to the request argument provided to the service. * * This function should be implemented by a TripalWebService child class. * */ public function handleRequest() { // TODO: make sure the $this->path and $this->params are set before // continuing. } // -------------------------------------------------------------------------- // CLASS FUNCTIONS -- DO NOT OVERRIDE // -------------------------------------------------------------------------- /** * Sets the URL path for the resource being called. * * @param $path * An array containing the elements of the URL path. Each level of the * URL appears in a separate element of the array. The service type and * version are automatically removed from the array. For example, a * URL of the type http://localhost/web-services/content/v0.1/Gene/sequence * will result in a $path array containing the following: * @code * array( * 'Gene', * 'sequence', * ); * @endcode * * @param unknown $path */ public function setPath($path) { $this->path = $path; } /** * Sets the parameters for the resource. * * @param $params * The set of paramters provided to the sesrvice. These are the values * that would occur in a URL after the question mark in an HTTP GET or * the data items of an HTTP POST. */ public function setParams($params) { $this->params = $params; } /** * Retrieves the version number for this web service. * * Each web service must have version number built into the name of the * class. The version number appears at the end of the class name, begins * with a lower-case 'v' and is followed by two numbers (major and minor) that * are separated by an underscore. This function identifies the version * from the class name and returns it here in a human-readable format. * * @param $sanitize * Set to TRUE to convert the period to underscore. * * @return * The version number for this web service. */ public function getVersion($sanitize = FALSE) { $class = get_class($this); $major_version = ''; $minor_version = ''; if (preg_match('/v(\d+)_(\d+)$/', $class, $matches)) { $major_version = $matches[1]; $minor_version = $matches[2]; if ($sanitize) { return 'v' . $major_version . '_' . $minor_version; } return 'v' . $major_version . '.' . $minor_version; } return ''; } /** * Retrieves the context section of the response. * * The JSON-LD response constists of two sections the '@context' section * and the data section. This function only returns the context section * of the response. * * @return * An associative array containing the context section of the response. */ public function getContext() { return $this->resource->getContext(); } /** * Returns the full web service response. * * The response includes both the @context and data sections of the * JSON-LD response. * * @return * An associative array containing that can be converted to JSON. */ public function getResponse() { $class = get_called_class(); $context_filename = $class::$type . '.' . $this->getVersion(TRUE); foreach ($this->path as $element) { $context_filename .= '.' . $element; } $context_filename .= '.json'; $context_filename = strtolower($context_filename); $context_dir = 'public://tripal/ws/context'; $context_file_path = $context_dir . '/' . $context_filename; // Make sure the user directory exists if (!file_prepare_directory($context_dir, FILE_CREATE_DIRECTORY)) { throw new Exception('Could not access the tripal/ws/context directory on the server for storing web services context files.'); } $context = $this->resource ? $this->resource->getContext() : array(); $context = array( '@context' => $context ); $cfh = fopen($context_file_path, "w"); if (flock($cfh, LOCK_EX)) { fwrite($cfh, json_encode($context)); flock($cfh, LOCK_UN); fclose($cfh); } else { throw new Exception(t('Error locking file: @file.', array('@file' => $context_file_path))); } $fid = db_select('file_managed', 'fm') ->fields('fm', array('fid')) ->condition('uri', $context_file_path) ->execute() ->fetchField(); // Save the context file so Drupal can manage it and remove the file later. if (!$fid) { $context_file = new stdClass(); $context_file->uri = $context_file_path; $context_file->filename = $context_filename; $context_file->filemime = 'application/ld+json'; $context_file->uid = 0; file_save($context_file); } $type = $this->resource ? $this->resource->getType() : 'unknown'; $json_ld = array( '@context' => file_create_url($context_file_path), '@id' => '', '@type' => $type, ); $data = $this->getData(); return array_merge($json_ld, $data); } /** * Retrieves the service URL for this service. */ public function getServicePath() { $class = get_class($this); $version = $this->getVersion(); $type = $class::$type; return $this->base_path . '/' . $type . '/' . $version; } /** * Retrieves the data section of the response. * * The JSON-LD response constists of two sections the '@context' section * and the data section. This function only returns the data section * of the response. * * @return * An associative array containing the data section of the response. */ public function getData() { if ($this->resource) { return $this->resource->getData(); } return array(); } /** * Sets the resource to be returned by this web service. * * @param $resource. * An implementation of a TripalWebServiceResource. */ public function setResource($resource) { // Make sure the $servcie provides is a TripalWebServcie class. if (!is_a($resource, 'TripalWebServiceResource')) { throw new Exception("Cannot add a new resource to this web service as it is not a TripalWebServiceResource."); } $this->resource = $resource; } /** * Set an error for the service. * * @param $message * The error message to report. */ public function setError($message) { $this->resource = new TripalWebServiceResource($this->base_path); $this->resource->setID('error'); $this->resource->addContextItem('error', 'rdfs:error'); $this->resource->setType('error'); $this->resource->addProperty('error', $message); } /** * Retrieves an array contining the supported classes. * * Supported classe are resources provided by this web services and the * operations supported by those classes. * * @return * An array of TripalWebServiceResource objects that follow the Hydra * documentation for documenting supported classes. */ public function getDocumentation() { return $this->documentation; } /** * Defines an entity class for the web services. * * A class defines a resource including information about its properties * and the actions that can be performed. Each class as a unique @id, * title, type and description. The $details parameter is used to provide * this information. Additionally, a resource may support Create, Read * Update and Delete (CRUD) operations. Those are defined using the * $ops argument. Finally, resources may have properties (or fields). These * properties should be defined using the $props arugment. * * @param $details. * An array of key/value pairs providing the details for the class. Valid * keys include: * - id: The unique IRI for this class. * - term: the accession for the term for this class. * - title: The title for the resource that this Class represents. * - description: (Optional). A description of the resource. * - subClassOf: (Optional). If this class is a subclass of another * class then the value should be the @id of the parent class. This * defaults to hydra:Resource. If no subClass is desired, set it * to NULL. * - type: (Optional). Indicates the type of class. Defaults to * hydra:Class * @param $ops * If the resource supports CRUD functionality then those functions should * be defined using this argument. This is an associative array with * the following keys: GET, POST, PUT, DELETE. These keys, if provided, * indicate that a resource of this type can be retrieved (GET), * created (POST), updated (PUT) or deleted (DELETE). The value for each * key should be an associative array that supports the following keys: * = type: the @id that determines the type of operation. This type * should be specific to the resource, and it need not be a term * from a real vocabulary. Use the '_:' prefix for the term. For * example, for an 'Event' resource with a GET method, an appropriate * type would be '_:event_retrieve'. * - label: A label that describes the operation in the * context of the resource. * - description: A description for the operation. Can be set to NULL * for no description. * - expects: The information expected by the Web API. * - returns: The @id of a Class that will be returned by * the operation. Set to NULL if there is no return value. * - statusCodes: An array of status codes that could be returned when * an error occurs. Each element of the array is an associative * array with two key/value pairs: 'code' and 'description'. Set the * 'code' to be the HTTP code that can be returned on error and the * 'description' to an error message appropriate for the error. For * example an HTTP 404 error means "Not Found". You can sepecify this * code and provide a description appropriate for the method and * class. * @param $props. * Defines the list of properties that the resource provides. This is an * array of properties where each property is an associative array * containing the following keys: * - type: The @id of the type of property. Alternatively, this can * be an instance of a TripalWebServiceResource when the property * must support operations such as a property of type hydra:Link. * - title: (Optional). The human-readable title of this property. If * this key is absent then the title will be set to the term's title. * - description: (Optional). A short description of this property. If * this key is absent then the description will be set to the term's * description. * - required: Set to TRUE to indicate if this property is a required * field when creating a new resource. * - readable: Set to TRUE to indicate that the client can retrieve the * property's value? * altered by an update. * - writeable: Set to TRUE if the client can alter the value of the * property. * - domain: the @id of the rdfs:domain. * - range: the @id of the rdfs:range. */ protected function addDocClass($details = array(), $ops = array(), $props = array()) { $supported_class = new TripalWebServiceResource($this->getServicePath()); // Add the context which all classes will need $supported_class->addContextItem('description', 'rdfs:comment'); $supported_class->addContextItem('subClassOf', 'hydra:subClassOf'); $supported_class->addContextItem('description', 'rdfs:comment'); $supported_class->addContextItem('label', 'rdfs:label'); // Set the Class ID. $class_id = $details['id']; $accession = $details['term']; if ($accession != $class_id) { $supported_class->addContextItem($accession, $class_id); } $supported_class->setID($accession); // Set the class Type. if (array_key_exists('type', $details)) { $supported_class->setType($details['type']); } else { $supported_class->setType('hydra:Class'); } // Set title and description. $supported_class->addProperty('hydra:title', $details['title']); $supported_class->addProperty('hydra:description', array_key_exists('description', $details) ? $details['description'] : NULL); // Set the sub class. if (array_key_exists('subClassOf', $details)) { if ($details['subClassOf']) { $supported_class->addProperty('subClassOf', $details['subClassOf']); } } else { $supported_class->addProperty('subClassOf', 'hydra:Resource'); } // Now add the supported operations. $class_ops = array(); foreach ($ops as $op => $op_details) { $class_ops[] = $this->generateDocClassOp($supported_class, $op, $op_details); } $supported_class->addContextItem('supportedOperation', 'hydra:supportedOperation'); $supported_class->addProperty('supportedOperation', $class_ops); // Now add in the supported proprerties. $class_props = array(); foreach ($props as $prop) { $class_props[] = $this->generateDocClassProp($supported_class, $prop); } $supported_class->addContextItem('supportedProperty', 'hydra:supportedProperty'); $supported_class->addProperty('supportedProperty', $class_props); $this->documentation[] = $supported_class; } /** * A helper function for the addClass() function for generating a property. */ private function generateDocClassProp($supported_class, $prop) { $supported_class->addContextItem('property', array( "@id" => "hydra:property", "@type" => "@id" )); $supported_class->addContextItem('domain', array( "@id" => "rdfs:domain", "@type" => "@id" )); $supported_class->addContextItem('range', array( "@id" => "rdfs:range", "@type" => "@id" )); $supported_class->addContextItem('readable', 'hydra:readable'); $supported_class->addContextItem('writeable', 'hydra:writeable'); $supported_class->addContextItem('required', 'hydra:required'); $supported_class->addContextItem('tripal_formatters', 'tripal:tripal_formatters'); $class_prop = array( 'property' => $prop['type'], 'hydra:title' => $prop['title'], 'hydra:description' => array_key_exists('description', $prop) ? $prop['description'] : NULL, 'required' => array_key_exists('required', $prop) ? $prop['required'] : NULL, 'readable' => array_key_exists('readonly', $prop) ? $prop['readonly'] : NULL, 'writeable' => array_key_exists('writeonly', $prop) ? $prop['writeonly'] : NULL, ); if (array_key_exists('domain', $prop)) { $class_prop['domain'] = $prop['domain']; } if (array_key_exists('range', $prop)) { $class_prop['range'] = $prop['range']; } if (array_key_exists('operations', $prop)) { $class_prop['supportedOperation'] = array(); foreach ($prop['operations'] as $op => $op_details) { $class_prop['supportedOperation'][] = $this->generateOp($supported_class, $op, $op_details); } } if (array_key_exists('tripal_formatters', $prop)) { $class_prop['tripal_formatters'] = array_keys($prop['tripal_formatters']); } return $class_prop; } /** * A helper function for the addClass() function for generating an operation. */ private function generateDocClassOp($supported_class, $op, $op_details) { if ($op != 'GET' and $op != 'PUT' and $op != 'DELETE' and $op != 'POST') { throw new Exception(t('The method, @method, provided to the TripalWebService::addClass function is not an oppropriate operations.', array('@method' => $op))); } if (!array_key_exists('type', $op_details)) { throw new Exception(t('Please provide a type in the operations array passed to the TripalWebService::addClass() function: @details', array('@details' => print_r($op_details, TRUE)))); } if (!array_key_exists('label', $op_details)) { throw new Exception(t('Please provide a label in the operations array passed to the TripalWebService::addClass() function: @details', array('@details' => print_r($op_details, TRUE)))); } $class_op = new TripalWebServiceResource($this->base_path); $class_op->setID($op_details['type']); switch($op) { case 'GET': $class_op->setType('hydra:Operation'); break; case 'POST': $class_op->setType('http://schema.org/AddAction'); break; case 'DELETE': $class_op->setType('http://schema.org/DeleteAction'); break; case 'PUT': $class_op->setType('http://schema.org/UpdateAction'); break; } $class_op->addContextItem('method', 'hydra:method'); $class_op->addContextItem('label', 'rdfs:label'); $class_op->addContextItem('description', 'rdfs:comment'); $class_op->addContextItem('expects', array( "@id" => "hydra:expects", "@type" => "@id" )); $class_op->addContextItem('returns', array( "@id" => "hydra:returns", "@type" => "@id" )); $class_op->addContextItem('statusCodes', 'hydra:statusCodes'); $class_op->addContextItem('code', 'hydra:statusCode'); $class_op->addProperty('method', $op); $class_op->addProperty('label', array_key_exists('label', $op_details) ? $op_details['label'] : 'Retrieves an instance of this resource'); $class_op->addProperty('description', array_key_exists('description', $op_details) ? $op_details['description'] : NULL); $status_codes = array_key_exists('statusCodes', $op_details) ? $op_details['statusCodes'] : array(); foreach ($status_codes as $code) { if (array_key_exists('code', $code) and array_key_exists('description', $code)) { $class_op->addProperty('statusCodes', $code); } else { throw new Exception(t('The status code provided to TripalWebService::addClass function is improperly formatted @code.', array('@code' => print_r($code, TRUE)))); } } if (count($status_codes) == 0) { $class_op->addProperty('statusCodes', array()); } $class_op->addProperty('expects', array_key_exists('expects', $op_details) ? $op_details['expects'] : NULL); $class_op->addProperty('returns', array_key_exists('returns', $op_details) ? $op_details['returns'] : ' "http://www.w3.org/2002/07/owl#Nothing",'); return $class_op; } /** * Converts a term array into an value appropriate for an @id or @type. * * @param $term * The term array. * @param $santize * An array of keywords indicating how to santize the key. By default, * no sanitizing occurs. The two valid types are 'lowercase', and 'spacing' * where 'lowercase' converts the term name to all lowercase and * 'spacing' replaces any spaces with underscores. * * @return * The id (the term name but with spaces replaced with underscores). */ protected function getContextTerm($term, $sanitize = array()) { if (!$term) { $backtrace = debug_backtrace(); throw new Exception('getContextTerm: Please provide a non NUll or non empty $term.'); } if (!$term['name']) { throw new Exception('getContextTerm: The provided term does not have a name: ' . print_r($term, TRUE)); } $key = $term['name']; $key_adj = $key; if (in_array('spacing', $sanitize)) { $key_adj = preg_replace('/ /', '_', $key_adj); } if (in_array('lowercase', $sanitize)) { $key_adj = strtolower($key_adj); } return $key_adj; } /** * Adds a term to the '@context' section for a given resource. * * @param $resource * A TripalWebServiceResource instance. * @param $term * The term array. * @param $santize * An array of keywords indicating how to santize the key. By default, * no sanitizing occurs. The two valid types are 'lowercase', and 'spacing' * where 'lowercase' converts the term name to all lowercase and * 'spacing' replaces any spaces with underscores. * @return * The id (the term name but with spaces replaced with underscores). */ protected function addContextTerm($resource, $term, $sanitize = array()) { if (!is_a($resource, 'TripalWebServiceResource')) { throw new Exception('addContextTerm: Please provide a $resource of type TripalWebServiceResource.'); } if (!$term) { $backtrace = debug_backtrace(); throw new Exception('addContextTerm: Please provide a non NUll or non empty $term.'); } if (!$term['name']) { throw new Exception('addContextTerm: The provided term does not have a name: ' . print_r($term, TRUE)); } // Make sure the vocab is present $vocab = $term['vocabulary']; $this->addContextVocab($resource, $vocab); // Sanitize the term key $key_adj = $this->getContextTerm($term, $sanitize); // Create the compact IRI $compact_iri = $vocab['short_name'] . ':' . $term['accession']; // If the full naming is indicated in the service parameters then // set the full name of the keys to include the vocab short name. if (array_key_exists('full_keys', $this->params)) { //$key_adj = $vocab['short_name'] . ':' . $key_adj; } $iri = $term['url']; $resource->addContextItem($key_adj, $compact_iri); $resource->addContextItem($compact_iri, $iri); return $key_adj; } /** * Adds a vocabulary to the '@context' section for a given resource. * * @param $resource * A TripalWebServiceResource instance. * @param $vocab * The vocabulary array. */ protected function addContextVocab($resource, $vocab) { if (!is_a($resource, 'TripalWebServiceResource')) { throw new Exception('addContextVocab: Please provide a $resource of type TripalWebServiceResource.'); } $key = $vocab['short_name']; // The URL here should be the URL prefix not the database home // page. But unfortunately, the URL prefix can't be guaranteed to be // a true prefix. Not all databases place by the rules. For this reason, // we can never use JSON-LD compact IRIs. :-( $iri = $vocab['sw_url']; $resource->addContextItem($key, $iri); } /** * Adds a key/value property to the given resource. * * @param $resource * A TripalWebServiceResource instance. * @param $term * The term array for the key. * @param $value * The value to add. * @param $santize * An array of keywords indicating how to santize the key. By default, * no sanitizing occurs. The two valid types are 'lowercase', and 'spacing' * where 'lowercase' converts the term name to all lowercase and * 'spacing' replaces any spaces with underscores. * @return $key * The key (the term name but with spaces replaced with underscores). */ public function addResourceProperty($resource, $term, $value, $sanitize = array()) { if (!is_a($resource, 'TripalWebServiceResource')) { throw new Exception('addProperty: Please provide a $resource of type TripalWebServiceResource.'); } // First add the term $key = $this->addContextTerm($resource, $term, $sanitize); // Then add the property. $resource->addProperty($key, $value); } /** * Sets the type for the given resource. * * The type exist in the context of the web service. * * @param $resource * A TripalWebServiceResource instance. * @param $type * The type * @param $santize * An array of keywords indicating how to santize the key. By default, * no sanitizing occurs. The two valid types are 'lowercase', and 'spacing' * where 'lowercase' converts the term name to all lowercase and * 'spacing' replaces any spaces with underscores. */ public function setResourceType($resource, $term, $sanitize = array('spacing')) { if (!is_a($resource, 'TripalWebServiceResource')) { throw new Exception('addProperty: Please provide a $resource of type TripalWebServiceResource.'); } // First add the term $key = $this->addContextTerm($resource, $term, $sanitize); // Then set the type $resource->setType($key); } }