Hawkin
/
arangodb
mirror of https://gitee.com/bigwinds/arangodb
1
0
Fork 0
Code Issues Projects Releases Wiki Activity
arangodb/arangod/RestHandler/RestCursorHandler.cpp

970 lines
33 KiB
C++
Raw Blame History

////////////////////////////////////////////////////////////////////////////////
/// @brief cursor request handler
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
/// @author Copyright 2014, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2010-2014, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "RestCursorHandler.h"
#include "Aql/Query.h"
#include "Aql/QueryRegistry.h"
#include "Basics/Exceptions.h"
#include "Basics/json.h"
#include "Basics/MutexLocker.h"
#include "Basics/ScopeGuard.h"
#include "Utils/Cursor.h"
#include "Utils/CursorRepository.h"
#include "V8Server/ApplicationV8.h"
using namespace triagens::arango;
using namespace triagens::rest;
// -----------------------------------------------------------------------------
// --SECTION-- constructors and destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief constructor
////////////////////////////////////////////////////////////////////////////////
RestCursorHandler::RestCursorHandler (HttpRequest* request,
std::pair<triagens::arango::ApplicationV8*, triagens::aql::QueryRegistry*>* pair)
: RestVocbaseBaseHandler(request),
_applicationV8(pair->first),
_queryRegistry(pair->second),
_queryLock(),
_query(nullptr),
_queryKilled(false) {
}
// -----------------------------------------------------------------------------
// --SECTION-- Handler methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// {@inheritDoc}
////////////////////////////////////////////////////////////////////////////////
HttpHandler::status_t RestCursorHandler::execute () {
// extract the sub-request type
HttpRequest::HttpRequestType type = _request->requestType();
if (type == HttpRequest::HTTP_REQUEST_POST) {
createCursor();
return status_t(HANDLER_DONE);
}
if (type == HttpRequest::HTTP_REQUEST_PUT) {
modifyCursor();
return status_t(HANDLER_DONE);
}
if (type == HttpRequest::HTTP_REQUEST_DELETE) {
deleteCursor();
return status_t(HANDLER_DONE);
}
generateError(HttpResponse::METHOD_NOT_ALLOWED, TRI_ERROR_HTTP_METHOD_NOT_ALLOWED);
return status_t(HANDLER_DONE);
}
////////////////////////////////////////////////////////////////////////////////
/// {@inheritDoc}
////////////////////////////////////////////////////////////////////////////////
bool RestCursorHandler::cancel (bool running) {
if (running) {
cancelQuery();
return true;
}
generateCanceled();
return true;
}
// -----------------------------------------------------------------------------
// --SECTION-- private methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief register the currently running query
////////////////////////////////////////////////////////////////////////////////
void RestCursorHandler::registerQuery (triagens::aql::Query* query) {
MUTEX_LOCKER(_queryLock);
TRI_ASSERT(_query == nullptr);
_query = query;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief unregister the currently running query
////////////////////////////////////////////////////////////////////////////////
void RestCursorHandler::unregisterQuery () {
MUTEX_LOCKER(_queryLock);
_query = nullptr;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief cancel the currently running query
////////////////////////////////////////////////////////////////////////////////
bool RestCursorHandler::cancelQuery () {
MUTEX_LOCKER(_queryLock);
if (_query != nullptr) {
_query->killed(true);
_queryKilled = true;
return true;
}
return false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief whether or not the query was cancelled
////////////////////////////////////////////////////////////////////////////////
bool RestCursorHandler::wasCancelled () {
MUTEX_LOCKER(_queryLock);
return _queryKilled;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief build options for the query as JSON
////////////////////////////////////////////////////////////////////////////////
triagens::basics::Json RestCursorHandler::buildOptions (TRI_json_t const* json) {
auto getAttribute = [&json] (char const* name) {
return TRI_LookupObjectJson(json, name);
};
triagens::basics::Json options(triagens::basics::Json::Object, 3);
auto attribute = getAttribute("count");
options.set("count", triagens::basics::Json(TRI_IsBooleanJson(attribute) ? attribute->_value._boolean : false));
attribute = getAttribute("batchSize");
options.set("batchSize", triagens::basics::Json(TRI_IsNumberJson(attribute) ? attribute->_value._number : 1000.0));
if (TRI_IsNumberJson(attribute) && static_cast<size_t>(attribute->_value._number) == 0) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_TYPE_ERROR, "expecting non-zero value for <batchSize>");
}
attribute = getAttribute("options");
if (TRI_IsObjectJson(attribute)) {
size_t const n = TRI_LengthVector(&attribute->_value._objects);
for (size_t i = 0; i < n; i += 2) {
auto key = static_cast<TRI_json_t const*>(TRI_AtVector(&attribute->_value._objects, i));
auto value = static_cast<TRI_json_t const*>(TRI_AtVector(&attribute->_value._objects, i + 1));
if (! TRI_IsStringJson(key) || value == nullptr) {
continue;
}
auto keyName = key->_value._string.data;
if (strcmp(keyName, "count") != 0 &&
strcmp(keyName, "batchSize") != 0) {
options.set(keyName, triagens::basics::Json(
TRI_UNKNOWN_MEM_ZONE,
TRI_CopyJson(TRI_UNKNOWN_MEM_ZONE, value),
triagens::basics::Json::NOFREE
));
}
}
}
if (! options.has("ttl")) {
attribute = getAttribute("ttl");
options.set("ttl", triagens::basics::Json(TRI_IsNumberJson(attribute) ? attribute->_value._number : 30.0));
}
return options;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief builds the "extra" attribute values from the result.
/// note that the "extra" object will take ownership from the result for
/// several values
////////////////////////////////////////////////////////////////////////////////
triagens::basics::Json RestCursorHandler::buildExtra (triagens::aql::QueryResult& queryResult) {
// build "extra" attribute
triagens::basics::Json extra(triagens::basics::Json::Object);
if (queryResult.stats != nullptr) {
extra.set("stats", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.stats, triagens::basics::Json::AUTOFREE));
queryResult.stats = nullptr;
}
if (queryResult.profile != nullptr) {
extra.set("profile", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.profile, triagens::basics::Json::AUTOFREE));
queryResult.profile = nullptr;
}
if (queryResult.warnings == nullptr) {
extra.set("warnings", triagens::basics::Json(triagens::basics::Json::Array));
}
else {
extra.set("warnings", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.warnings, triagens::basics::Json::AUTOFREE));
queryResult.warnings = nullptr;
}
return extra;
}
////////////////////////////////////////////////////////////////////////////////
/// @startDocuBlock JSF_post_api_cursor
/// @brief create a cursor and return the first results
///
/// @RESTHEADER{POST /_api/cursor, Create cursor}
///
/// @RESTBODYPARAM{query,json,required}
/// A JSON object describing the query and query parameters.
///
/// @RESTDESCRIPTION
/// The query details include the query string plus optional query options and
/// bind parameters. These values need to be passed in a JSON representation in
/// the body of the POST request.
///
/// The following attributes can be used inside the JSON object:
///
/// - *query*: contains the query string to be executed (mandatory)
///
/// - *count*: boolean flag that indicates whether the number of documents
/// in the result set should be returned in the "count" attribute of the result (optional).
/// Calculating the "count" attribute might in the future have a performance
/// impact for some queries so this option is turned off by default, and "count"
/// is only returned when requested.
///
/// - *batchSize*: maximum number of result documents to be transferred from
/// the server to the client in one roundtrip (optional). If this attribute is
/// not set, a server-controlled default value will be used.
///
/// - *ttl*: an optional time-to-live for the cursor (in seconds). The cursor will be
/// removed on the server automatically after the specified amount of time. This
/// is useful to ensure garbage collection of cursors that are not fully fetched
/// by clients. If not set, a server-defined value will be used.
///
/// - *bindVars*: key/value list of bind parameters (optional).
///
/// - *options*: key/value list of extra options for the query (optional).
///
/// The following options are supported at the moment:
///
/// - *fullCount*: if set to *true* and the query contains a *LIMIT* clause, then the
/// result will contain an extra attribute *extra* with a sub-attribute *fullCount*.
/// This sub-attribute will contain the number of documents in the result before the
/// last LIMIT in the query was applied. It can be used to count the number of documents that
/// match certain filter criteria, but only return a subset of them, in one go.
/// It is thus similar to MySQL's *SQL_CALC_FOUND_ROWS* hint. Note that setting the option
/// will disable a few LIMIT optimizations and may lead to more documents being processed,
/// and thus make queries run longer. Note that the *fullCount* sub-attribute will only
/// be present in the result if the query has a LIMIT clause and the LIMIT clause is
/// actually used in the query.
///
/// - *maxPlans*: limits the maximum number of plans that are created by the AQL
/// query optimizer.
///
/// - *optimizer.rules*: a list of to-be-included or to-be-excluded optimizer rules
/// can be put into this attribute, telling the optimizer to include or exclude
/// specific rules. To disable a rule, prefix its name with a `-`, to enable a rule, prefix it
/// with a `+`. There is also a pseudo-rule `all`, which will match all optimizer rules.
///
/// If the result set can be created by the server, the server will respond with
/// *HTTP 201*. The body of the response will contain a JSON object with the
/// result set.
///
/// The returned JSON object has the following properties:
///
/// - *error*: boolean flag to indicate that an error occurred (*false*
/// in this case)
///
/// - *code*: the HTTP status code
///
/// - *result*: an array of result documents (might be empty if query has no results)
///
/// - *hasMore*: a boolean indicator whether there are more results
/// available for the cursor on the server
///
/// - *count*: the total number of result documents available (only
/// available if the query was executed with the *count* attribute set)
///
/// - *id*: id of temporary cursor created on the server (optional, see above)
///
/// - *extra*: an optional JSON object with extra information about the query result.
/// For data-modification queries, the *extra* attribute will contain the number
/// of modified documents and the number of documents that could not be modified
/// due to an error (if *ignoreErrors* query option is specified)
///
/// If the JSON representation is malformed or the query specification is
/// missing from the request, the server will respond with *HTTP 400*.
///
/// The body of the response will contain a JSON object with additional error
/// details. The object has the following attributes:
///
/// - *error*: boolean flag to indicate that an error occurred (*true* in this case)
///
/// - *code*: the HTTP status code
///
/// - *errorNum*: the server error number
///
/// - *errorMessage*: a descriptive error message
///
/// If the query specification is complete, the server will process the query. If an
/// error occurs during query processing, the server will respond with *HTTP 400*.
/// Again, the body of the response will contain details about the error.
///
/// A list of query errors can be found (../ArangoErrors/README.md) here.
///
/// @RESTRETURNCODES
///
/// @RESTRETURNCODE{201}
/// is returned if the result set can be created by the server.
///
/// @RESTRETURNCODE{400}
/// is returned if the JSON representation is malformed or the query specification is
/// missing from the request.
///
/// @RESTRETURNCODE{404}
/// The server will respond with *HTTP 404* in case a non-existing collection is
/// accessed in the query.
///
/// @RESTRETURNCODE{405}
/// The server will respond with *HTTP 405* if an unsupported HTTP method is used.
///
/// @EXAMPLES
///
/// Executes a query and extract the result in a single go:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorCreateCursorForLimitReturnSingle}
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({"hello1":"world1"});
/// db.products.save({"hello2":"world1"});
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR p IN products LIMIT 2 RETURN p",
/// count: true,
/// batchSize: 2
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Executes a query and extracts part of the result:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorCreateCursorForLimitReturn}
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({"hello1":"world1"});
/// db.products.save({"hello2":"world1"});
/// db.products.save({"hello3":"world1"});
/// db.products.save({"hello4":"world1"});
/// db.products.save({"hello5":"world1"});
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR p IN products LIMIT 5 RETURN p",
/// count: true,
/// batchSize: 2
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Using query option "fullCount":
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorCreateCursorOption}
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR i IN 1..1000 FILTER i > 500 LIMIT 10 RETURN i",
/// count: true,
/// options: {
/// fullCount: true
/// }
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Enabling and disabling optimizer rules:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorOptimizerRules}
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR i IN 1..10 LET a = 1 LET b = 2 FILTER a + b == 3 RETURN i",
/// count: true,
/// options: {
/// maxPlans: 1,
/// optimizer: {
/// rules: [ "-all", "+remove-unnecessary-filters" ]
/// }
/// }
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Executes a data-modification query and retrieves the number of
/// modified documents:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorDeleteQuery}
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({"hello1":"world1"});
/// db.products.save({"hello2":"world1"});
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR p IN products REMOVE p IN products"
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
/// assert(JSON.parse(response.body).extra.stats.writesExecuted === 2);
/// assert(JSON.parse(response.body).extra.stats.writesIgnored === 0);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Executes a data-modification query with option *ignoreErrors*:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorDeleteIgnore}
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({ _key: "foo" });
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "REMOVE 'bar' IN products OPTIONS { ignoreErrors: true }"
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 201);
/// assert(JSON.parse(response.body).extra.stats.writesExecuted === 0);
/// assert(JSON.parse(response.body).extra.stats.writesIgnored === 1);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Bad queries:
///
/// Missing body:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorCreateCursorMissingBody}
/// var url = "/_api/cursor";
///
/// var response = logCurlRequest('POST', url, '');
///
/// assert(response.code === 400);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Unknown collection:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorCreateCursorUnknownCollection}
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR u IN unknowncoll LIMIT 2 RETURN u",
/// count: true,
/// batchSize: 2
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 404);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Executes a data-modification query that attempts to remove a non-existing
/// document:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorDeleteQueryFail}
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({ _key: "bar" });
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "REMOVE 'foo' IN products"
/// };
///
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// assert(response.code === 404);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// @endDocuBlock
////////////////////////////////////////////////////////////////////////////////
void RestCursorHandler::createCursor () {
std::vector<std::string> const& suffix = _request->suffix();
if (suffix.size() != 0) {
generateError(HttpResponse::BAD,
TRI_ERROR_HTTP_BAD_PARAMETER,
"expecting POST /_api/cursor");
return;
}
try {
std::unique_ptr<TRI_json_t> json(parseJsonBody());
if (json.get() == nullptr) {
return;
}
if (! TRI_IsObjectJson(json.get())) {
generateError(HttpResponse::BAD, TRI_ERROR_QUERY_EMPTY);
return;
}
auto const* queryString = TRI_LookupObjectJson(json.get(), "query");
if (! TRI_IsStringJson(queryString)) {
generateError(HttpResponse::BAD, TRI_ERROR_QUERY_EMPTY);
return;
}
auto const* bindVars = TRI_LookupObjectJson(json.get(), "bindVars");
if (bindVars != nullptr) {
if (! TRI_IsObjectJson(bindVars) &&
! TRI_IsNullJson(bindVars)) {
generateError(HttpResponse::BAD, TRI_ERROR_TYPE_ERROR, "expecting object for <bindVars>");
return;
}
}
auto options = buildOptions(json.get());
triagens::aql::Query query(_applicationV8,
false,
_vocbase,
queryString->_value._string.data,
static_cast<size_t>(queryString->_value._string.length - 1),
(bindVars != nullptr ? TRI_CopyJson(TRI_UNKNOWN_MEM_ZONE, bindVars) : nullptr),
TRI_CopyJson(TRI_UNKNOWN_MEM_ZONE, options.json()),
triagens::aql::PART_MAIN);
registerQuery(&query);
auto queryResult = query.execute(_queryRegistry);
unregisterQuery();
if (queryResult.code != TRI_ERROR_NO_ERROR) {
if (queryResult.code == TRI_ERROR_REQUEST_CANCELED ||
(queryResult.code == TRI_ERROR_QUERY_KILLED && wasCancelled())) {
THROW_ARANGO_EXCEPTION(TRI_ERROR_REQUEST_CANCELED);
}
THROW_ARANGO_EXCEPTION_MESSAGE(queryResult.code, queryResult.details);
}
TRI_ASSERT(TRI_IsArrayJson(queryResult.json));
{
_response = createResponse(HttpResponse::CREATED);
_response->setContentType("application/json; charset=utf-8");
// build "extra" attribute
triagens::basics::Json extra(triagens::basics::Json::Object, 3);
if (queryResult.stats != nullptr) {
extra.set("stats", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.stats, triagens::basics::Json::AUTOFREE));
queryResult.stats = nullptr;
}
if (queryResult.profile != nullptr) {
extra.set("profile", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.profile, triagens::basics::Json::AUTOFREE));
queryResult.profile = nullptr;
}
if (queryResult.warnings == nullptr) {
extra.set("warnings", triagens::basics::Json(triagens::basics::Json::Array));
}
else {
extra.set("warnings", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.warnings, triagens::basics::Json::AUTOFREE));
queryResult.warnings = nullptr;
}
size_t batchSize = triagens::basics::JsonHelper::getNumericValue<size_t>(options.json(), "batchSize", 1000);
size_t const n = TRI_LengthArrayJson(queryResult.json);
if (n <= batchSize) {
// result is smaller than batchSize and will be returned directly. no need to create a cursor
triagens::basics::Json result(triagens::basics::Json::Object, 6);
result.set("result", triagens::basics::Json(TRI_UNKNOWN_MEM_ZONE, queryResult.json, triagens::basics::Json::AUTOFREE));
queryResult.json = nullptr;
result.set("hasMore", triagens::basics::Json(false));
if (triagens::basics::JsonHelper::getBooleanValue(options.json(), "count", false)) {
result.set("count", triagens::basics::Json(static_cast<double>(n)));
}
result.set("extra", extra);
result.set("error", triagens::basics::Json(false));
result.set("code", triagens::basics::Json(static_cast<double>(_response->responseCode())));
result.dump(_response->body());
return;
}
// result is bigger than batchSize, and a cursor will be created
auto cursors = static_cast<triagens::arango::CursorRepository*>(_vocbase->_cursorRepository);
TRI_ASSERT(cursors != nullptr);
double ttl = triagens::basics::JsonHelper::getNumericValue<double>(options.json(), "ttl", 30);
bool count = triagens::basics::JsonHelper::getBooleanValue(options.json(), "count", false);
// steal the query JSON, cursor will take over the ownership
auto j = queryResult.json;
triagens::arango::JsonCursor* cursor = cursors->createFromJson(j, batchSize, extra.steal(), ttl, count);
queryResult.json = nullptr;
try {
_response->body().appendChar('{');
cursor->dump(_response->body());
_response->body().appendText(",\"error\":false,\"code\":");
_response->body().appendInteger(static_cast<uint32_t>(_response->responseCode()));
_response->body().appendChar('}');
cursors->release(cursor);
}
catch (...) {
cursors->release(cursor);
throw;
}
}
}
catch (triagens::basics::Exception const& ex) {
unregisterQuery();
generateError(HttpResponse::responseCode(ex.code()), ex.code(), ex.what());
}
catch (...) {
unregisterQuery();
generateError(HttpResponse::SERVER_ERROR, TRI_ERROR_INTERNAL);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @startDocuBlock JSF_post_api_cursor_identifier
/// @brief return the next results from an existing cursor
///
/// @RESTHEADER{PUT /_api/cursor/{cursor-identifier}, Read next batch from cursor}
///
/// @RESTURLPARAMETERS
///
/// @RESTURLPARAM{cursor-identifier,string,required}
/// The name of the cursor
///
/// @RESTDESCRIPTION
///
/// If the cursor is still alive, returns an object with the following
/// attributes:
///
/// - *id*: the *cursor-identifier*
/// - *result*: a list of documents for the current batch
/// - *hasMore*: *false* if this was the last batch
/// - *count*: if present the total number of elements
///
/// Note that even if *hasMore* returns *true*, the next call might
/// still return no documents. If, however, *hasMore* is *false*, then
/// the cursor is exhausted. Once the *hasMore* attribute has a value of
/// *false*, the client can stop.
///
/// @RESTRETURNCODES
///
/// @RESTRETURNCODE{200}
/// The server will respond with *HTTP 200* in case of success.
///
/// @RESTRETURNCODE{400}
/// If the cursor identifier is omitted, the server will respond with *HTTP 404*.
///
/// @RESTRETURNCODE{404}
/// If no cursor with the specified identifier can be found, the server will respond
/// with *HTTP 404*.
///
/// @EXAMPLES
///
/// Valid request for next batch:
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorForLimitReturnCont}
/// var url = "/_api/cursor";
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({"hello1":"world1"});
/// db.products.save({"hello2":"world1"});
/// db.products.save({"hello3":"world1"});
/// db.products.save({"hello4":"world1"});
/// db.products.save({"hello5":"world1"});
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR p IN products LIMIT 5 RETURN p",
/// count: true,
/// batchSize: 2
/// };
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
///
/// var body = response.body.replace(/\\/g, '');
/// var _id = JSON.parse(body).id;
/// response = logCurlRequest('PUT', url + '/' + _id, '');
/// assert(response.code === 200);
///
/// logJsonResponse(response);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Missing identifier
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorMissingCursorIdentifier}
/// var url = "/_api/cursor";
///
/// var response = logCurlRequest('PUT', url, '');
///
/// assert(response.code === 400);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
///
/// Unknown identifier
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorInvalidCursorIdentifier}
/// var url = "/_api/cursor/123123";
///
/// var response = logCurlRequest('PUT', url, '');
///
/// assert(response.code === 404);
///
/// logJsonResponse(response);
/// @END_EXAMPLE_ARANGOSH_RUN
/// @endDocuBlock
////////////////////////////////////////////////////////////////////////////////
void RestCursorHandler::modifyCursor () {
std::vector<std::string> const& suffix = _request->suffix();
if (suffix.size() != 1) {
generateError(HttpResponse::BAD,
TRI_ERROR_HTTP_BAD_PARAMETER,
"expecting PUT /_api/cursor/<cursor-id>");
return;
}
std::string const& id = suffix[0];
auto cursors = static_cast<triagens::arango::CursorRepository*>(_vocbase->_cursorRepository);
TRI_ASSERT(cursors != nullptr);
auto cursorId = static_cast<triagens::arango::CursorId>(triagens::basics::StringUtils::uint64(id));
bool busy;
auto cursor = cursors->find(cursorId, busy);
if (cursor == nullptr) {
if (busy) {
generateError(HttpResponse::responseCode(TRI_ERROR_CURSOR_BUSY), TRI_ERROR_CURSOR_BUSY);
}
else {
generateError(HttpResponse::responseCode(TRI_ERROR_CURSOR_NOT_FOUND), TRI_ERROR_CURSOR_NOT_FOUND);
}
return;
}
try {
_response = createResponse(HttpResponse::OK);
_response->setContentType("application/json; charset=utf-8");
_response->body().appendChar('{');
cursor->dump(_response->body());
_response->body().appendText(",\"error\":false,\"code\":");
_response->body().appendInteger(static_cast<uint32_t>(_response->responseCode()));
_response->body().appendChar('}');
cursors->release(cursor);
}
catch (triagens::basics::Exception const& ex) {
cursors->release(cursor);
generateError(HttpResponse::responseCode(ex.code()), ex.code(), ex.what());
}
catch (...) {
cursors->release(cursor);
generateError(HttpResponse::SERVER_ERROR, TRI_ERROR_INTERNAL);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @startDocuBlock JSF_post_api_cursor_delete
/// @brief dispose an existing cursor
///
/// @RESTHEADER{DELETE /_api/cursor/{cursor-identifier}, Delete cursor}
///
/// @RESTURLPARAMETERS
///
/// @RESTURLPARAM{cursor-identifier,string,required}
/// The id of the cursor
///
/// @RESTDESCRIPTION
/// Deletes the cursor and frees the resources associated with it.
///
/// The cursor will automatically be destroyed on the server when the client has
/// retrieved all documents from it. The client can also explicitly destroy the
/// cursor at any earlier time using an HTTP DELETE request. The cursor id must
/// be included as part of the URL.
///
/// Note: the server will also destroy abandoned cursors automatically after a
/// certain server-controlled timeout to avoid resource leakage.
///
/// @RESTRETURNCODES
///
/// @RESTRETURNCODE{202}
/// is returned if the server is aware of the cursor.
///
/// @RESTRETURNCODE{404}
/// is returned if the server is not aware of the cursor. It is also
/// returned if a cursor is used after it has been destroyed.
///
/// @EXAMPLES
///
/// @EXAMPLE_ARANGOSH_RUN{RestCursorDelete}
/// var url = "/_api/cursor";
/// var cn = "products";
/// db._drop(cn);
/// db._create(cn);
///
/// db.products.save({"hello1":"world1"});
/// db.products.save({"hello2":"world1"});
/// db.products.save({"hello3":"world1"});
/// db.products.save({"hello4":"world1"});
/// db.products.save({"hello5":"world1"});
///
/// var url = "/_api/cursor";
/// var body = {
/// query: "FOR p IN products LIMIT 5 RETURN p",
/// count: true,
/// batchSize: 2
/// };
/// var response = logCurlRequest('POST', url, JSON.stringify(body));
/// logJsonResponse(response);
/// var body = response.body.replace(/\\/g, '');
/// var _id = JSON.parse(body).id;
/// response = logCurlRequest('DELETE', url + '/' + _id);
///
/// assert(response.code === 202);
/// ~ db._drop(cn);
/// @END_EXAMPLE_ARANGOSH_RUN
/// @endDocuBlock
////////////////////////////////////////////////////////////////////////////////
void RestCursorHandler::deleteCursor () {
std::vector<std::string> const& suffix = _request->suffix();
if (suffix.size() != 1) {
generateError(HttpResponse::BAD,
TRI_ERROR_HTTP_BAD_PARAMETER,
"expecting DELETE /_api/cursor/<cursor-id>");
return;
}
std::string const& id = suffix[0];
auto cursors = static_cast<triagens::arango::CursorRepository*>(_vocbase->_cursorRepository);
TRI_ASSERT(cursors != nullptr);
auto cursorId = static_cast<triagens::arango::CursorId>(triagens::basics::StringUtils::uint64(id));
bool found = cursors->remove(cursorId);
if (! found) {
generateError(HttpResponse::NOT_FOUND, TRI_ERROR_CURSOR_NOT_FOUND);
return;
}
_response = createResponse(HttpResponse::ACCEPTED);
_response->setContentType("application/json; charset=utf-8");
triagens::basics::Json json(triagens::basics::Json::Object);
json.set("id", triagens::basics::Json(id)); // id as a string!
json.set("error", triagens::basics::Json(false));
json.set("code", triagens::basics::Json(static_cast<double>(_response->responseCode())));
json.dump(_response->body());
}
// -----------------------------------------------------------------------------
// --SECTION-- END-OF-FILE
// -----------------------------------------------------------------------------
// Local Variables:
// mode: outline-minor
// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @page\\|// --SECTION--\\|/// @\\}"
// End:
Reference in New Issue View Git Blame Copy Permalink