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2261 lines (1816 loc) · 57.3 KB
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// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License.
#include "graphqlservice/GraphQLService.h"
#include "graphqlservice/internal/Grammar.h"
#include "Validation.h"
#include <algorithm>
#include <array>
#include <iostream>
namespace graphql::service {
void addErrorMessage(std::string&& message, response::Value& error)
{
error.emplace_back(std::string { strMessage }, response::Value(std::move(message)));
}
void addErrorLocation(const schema_location& location, response::Value& error)
{
if (location.line == 0)
{
return;
}
response::Value errorLocation(response::Type::Map);
errorLocation.reserve(2);
errorLocation.emplace_back(std::string { strLine },
response::Value(static_cast<int>(location.line)));
errorLocation.emplace_back(std::string { strColumn },
response::Value(static_cast<int>(location.column)));
response::Value errorLocations(response::Type::List);
errorLocations.reserve(1);
errorLocations.emplace_back(std::move(errorLocation));
error.emplace_back(std::string { strLocations }, std::move(errorLocations));
}
void addErrorPath(const error_path& path, response::Value& error)
{
if (path.empty())
{
return;
}
response::Value errorPath(response::Type::List);
errorPath.reserve(path.size());
for (const auto& segment : path)
{
if (std::holds_alternative<std::string_view>(segment))
{
errorPath.emplace_back(
response::Value { std::string { std::get<std::string_view>(segment) } });
}
else if (std::holds_alternative<size_t>(segment))
{
errorPath.emplace_back(response::Value(static_cast<int>(std::get<size_t>(segment))));
}
}
error.emplace_back(std::string { strPath }, std::move(errorPath));
}
error_path buildErrorPath(const std::optional<field_path>& path)
{
error_path result;
if (path)
{
std::list<std::reference_wrapper<const path_segment>> segments;
for (auto segment = std::make_optional(std::cref(*path)); segment;
segment = segment->get().parent)
{
segments.push_front(std::cref(segment->get().segment));
}
result.reserve(segments.size());
std::transform(segments.cbegin(),
segments.cend(),
std::back_inserter(result),
[](const auto& segment) noexcept {
return segment.get();
});
}
return result;
}
response::Value buildErrorValues(std::list<schema_error>&& structuredErrors)
{
response::Value errors(response::Type::List);
errors.reserve(structuredErrors.size());
for (auto& error : structuredErrors)
{
response::Value entry(response::Type::Map);
entry.reserve(3);
addErrorMessage(std::move(error.message), entry);
addErrorLocation(error.location, entry);
addErrorPath(error.path, entry);
errors.emplace_back(std::move(entry));
}
return errors;
}
schema_exception::schema_exception(std::list<schema_error>&& structuredErrors)
: _structuredErrors(std::move(structuredErrors))
{
}
schema_exception::schema_exception(std::vector<std::string>&& messages)
: schema_exception(convertMessages(std::move(messages)))
{
}
std::list<schema_error> schema_exception::convertMessages(
std::vector<std::string>&& messages) noexcept
{
std::list<schema_error> errors;
std::transform(messages.begin(),
messages.end(),
std::back_inserter(errors),
[](std::string& message) noexcept {
return schema_error { std::move(message) };
});
return errors;
}
const char* schema_exception::what() const noexcept
{
const char* message = nullptr;
if (!_structuredErrors.empty())
{
message = _structuredErrors.front().message.c_str();
}
return (message == nullptr) ? "Unknown schema error" : message;
}
std::list<schema_error> schema_exception::getStructuredErrors() noexcept
{
auto structuredErrors = std::move(_structuredErrors);
return structuredErrors;
}
response::Value schema_exception::getErrors()
{
return buildErrorValues(std::move(_structuredErrors));
}
void await_worker_thread::await_suspend(coro::coroutine_handle<> h) const
{
std::thread(
[](coro::coroutine_handle<>&& h) {
h.resume();
},
std::move(h))
.detach();
}
await_worker_queue::await_worker_queue()
: _startId { std::this_thread::get_id() }
, _worker { [this]() {
resumePending();
} }
{
}
await_worker_queue::~await_worker_queue()
{
std::unique_lock lock { _mutex };
_shutdown = true;
lock.unlock();
_cv.notify_one();
_worker.join();
}
bool await_worker_queue::await_ready() const
{
return std::this_thread::get_id() != _startId;
}
void await_worker_queue::await_suspend(coro::coroutine_handle<> h)
{
std::unique_lock lock { _mutex };
_pending.push_back(std::move(h));
lock.unlock();
_cv.notify_one();
}
void await_worker_queue::resumePending()
{
std::unique_lock lock { _mutex };
while (!_shutdown)
{
_cv.wait(lock, [this]() {
return _shutdown || !_pending.empty();
});
auto pending = std::move(_pending);
lock.unlock();
for (auto h : pending)
{
h.resume();
}
lock.lock();
}
}
// Default to immediate synchronous execution.
await_async::await_async()
: _pimpl { std::static_pointer_cast<const Concept>(
std::make_shared<Model<coro::suspend_never>>(std::make_shared<coro::suspend_never>())) }
{
}
// Implicitly convert a std::launch parameter used with std::async to an awaitable.
await_async::await_async(std::launch launch)
: _pimpl { ((launch & std::launch::async) == std::launch::async)
? std::static_pointer_cast<const Concept>(std::make_shared<Model<await_worker_thread>>(
std::make_shared<await_worker_thread>()))
: std::static_pointer_cast<const Concept>(std::make_shared<Model<coro::suspend_never>>(
std::make_shared<coro::suspend_never>())) }
{
}
bool await_async::await_ready() const
{
return _pimpl->await_ready();
}
void await_async::await_suspend(coro::coroutine_handle<> h) const
{
_pimpl->await_suspend(std::move(h));
}
void await_async::await_resume() const
{
_pimpl->await_resume();
}
FieldParams::FieldParams(SelectionSetParams&& selectionSetParams, Directives directives)
: SelectionSetParams(std::move(selectionSetParams))
, fieldDirectives(std::move(directives))
{
}
// ValueVisitor visits the AST and builds a response::Value representation of any value
// hardcoded or referencing a variable in an operation.
class ValueVisitor
{
public:
ValueVisitor(const response::Value& variables);
void visit(const peg::ast_node& value);
response::Value getValue();
private:
void visitVariable(const peg::ast_node& variable);
void visitIntValue(const peg::ast_node& intValue);
void visitFloatValue(const peg::ast_node& floatValue);
void visitStringValue(const peg::ast_node& stringValue);
void visitBooleanValue(const peg::ast_node& booleanValue);
void visitNullValue(const peg::ast_node& nullValue);
void visitEnumValue(const peg::ast_node& enumValue);
void visitListValue(const peg::ast_node& listValue);
void visitObjectValue(const peg::ast_node& objectValue);
const response::Value& _variables;
response::Value _value;
};
ValueVisitor::ValueVisitor(const response::Value& variables)
: _variables(variables)
{
}
response::Value ValueVisitor::getValue()
{
auto result = std::move(_value);
return result;
}
void ValueVisitor::visit(const peg::ast_node& value)
{
if (value.is_type<peg::variable_value>())
{
visitVariable(value);
}
else if (value.is_type<peg::integer_value>())
{
visitIntValue(value);
}
else if (value.is_type<peg::float_value>())
{
visitFloatValue(value);
}
else if (value.is_type<peg::string_value>())
{
visitStringValue(value);
}
else if (value.is_type<peg::true_keyword>() || value.is_type<peg::false_keyword>())
{
visitBooleanValue(value);
}
else if (value.is_type<peg::null_keyword>())
{
visitNullValue(value);
}
else if (value.is_type<peg::enum_value>())
{
visitEnumValue(value);
}
else if (value.is_type<peg::list_value>())
{
visitListValue(value);
}
else if (value.is_type<peg::object_value>())
{
visitObjectValue(value);
}
}
void ValueVisitor::visitVariable(const peg::ast_node& variable)
{
const auto name = variable.string_view().substr(1);
auto itr = _variables.find(name);
if (itr == _variables.get<response::MapType>().cend())
{
auto position = variable.begin();
std::ostringstream error;
error << "Unknown variable name: " << name;
throw schema_exception {
{ schema_error { error.str(), { position.line, position.column } } }
};
}
_value = response::Value(itr->second);
}
void ValueVisitor::visitIntValue(const peg::ast_node& intValue)
{
_value = response::Value(std::atoi(intValue.string().c_str()));
}
void ValueVisitor::visitFloatValue(const peg::ast_node& floatValue)
{
_value = response::Value(std::atof(floatValue.string().c_str()));
}
void ValueVisitor::visitStringValue(const peg::ast_node& stringValue)
{
_value = response::Value(std::string { stringValue.unescaped_view() }).from_input();
}
void ValueVisitor::visitBooleanValue(const peg::ast_node& booleanValue)
{
_value = response::Value(booleanValue.is_type<peg::true_keyword>());
}
void ValueVisitor::visitNullValue(const peg::ast_node& /*nullValue*/)
{
_value = {};
}
void ValueVisitor::visitEnumValue(const peg::ast_node& enumValue)
{
_value = response::Value(response::Type::EnumValue);
_value.set<std::string>(enumValue.string());
}
void ValueVisitor::visitListValue(const peg::ast_node& listValue)
{
_value = response::Value(response::Type::List);
_value.reserve(listValue.children.size());
ValueVisitor visitor(_variables);
for (const auto& child : listValue.children)
{
visitor.visit(*child);
_value.emplace_back(visitor.getValue());
}
}
void ValueVisitor::visitObjectValue(const peg::ast_node& objectValue)
{
_value = response::Value(response::Type::Map);
_value.reserve(objectValue.children.size());
ValueVisitor visitor(_variables);
for (const auto& field : objectValue.children)
{
visitor.visit(*field->children.back());
_value.emplace_back(field->children.front()->string(), visitor.getValue());
}
}
// DirectiveVisitor visits the AST and builds a 2-level map of directive names to argument
// name/value pairs.
class DirectiveVisitor
{
public:
explicit DirectiveVisitor(const response::Value& variables);
void visit(const peg::ast_node& directives);
bool shouldSkip() const;
Directives getDirectives();
private:
const response::Value& _variables;
Directives _directives;
};
DirectiveVisitor::DirectiveVisitor(const response::Value& variables)
: _variables(variables)
{
}
void DirectiveVisitor::visit(const peg::ast_node& directives)
{
Directives result;
for (const auto& directive : directives.children)
{
std::string_view directiveName;
peg::on_first_child<peg::directive_name>(*directive,
[&directiveName](const peg::ast_node& child) {
directiveName = child.string_view();
});
if (directiveName.empty())
{
continue;
}
response::Value directiveArguments(response::Type::Map);
peg::on_first_child<peg::arguments>(*directive,
[this, &directiveArguments](const peg::ast_node& child) {
ValueVisitor visitor(_variables);
for (auto& argument : child.children)
{
visitor.visit(*argument->children.back());
directiveArguments.emplace_back(argument->children.front()->string(),
visitor.getValue());
}
});
result.emplace_back(directiveName, std::move(directiveArguments));
}
_directives = std::move(result);
}
Directives DirectiveVisitor::getDirectives()
{
auto result = std::move(_directives);
return result;
}
bool DirectiveVisitor::shouldSkip() const
{
constexpr std::array<std::pair<bool, std::string_view>, 2> c_skippedDirectives = {
std::make_pair(true, R"gql(skip)gql"sv),
std::make_pair(false, R"gql(include)gql"sv),
};
for (const auto& entry : c_skippedDirectives)
{
const bool skip = entry.first;
auto itrDirective = std::find_if(_directives.cbegin(),
_directives.cend(),
[directiveName = entry.second](const auto& directive) noexcept {
return directive.first == directiveName;
});
if (itrDirective == _directives.end())
{
continue;
}
auto& arguments = itrDirective->second;
if (arguments.type() != response::Type::Map)
{
std::ostringstream error;
error << "Invalid arguments to directive: " << entry.second;
throw schema_exception { { error.str() } };
}
bool argumentTrue = false;
bool argumentFalse = false;
for (auto& argument : arguments)
{
if (argumentTrue || argumentFalse || argument.second.type() != response::Type::Boolean
|| argument.first != "if")
{
std::ostringstream error;
error << "Invalid argument to directive: " << entry.second
<< " name: " << argument.first;
throw schema_exception { { error.str() } };
}
argumentTrue = argument.second.get<bool>();
argumentFalse = !argumentTrue;
}
if (argumentTrue)
{
return skip;
}
else if (argumentFalse)
{
return !skip;
}
else
{
std::ostringstream error;
error << "Missing argument directive: " << entry.second << " name: if";
throw schema_exception { { error.str() } };
}
}
return false;
}
Fragment::Fragment(const peg::ast_node& fragmentDefinition, const response::Value& variables)
: _type(fragmentDefinition.children[1]->children.front()->string_view())
, _selection(*(fragmentDefinition.children.back()))
{
peg::on_first_child<peg::directives>(fragmentDefinition,
[this, &variables](const peg::ast_node& child) {
DirectiveVisitor directiveVisitor(variables);
directiveVisitor.visit(child);
_directives = directiveVisitor.getDirectives();
});
}
std::string_view Fragment::getType() const
{
return _type;
}
const peg::ast_node& Fragment::getSelection() const
{
return _selection.get();
}
const Directives& Fragment::getDirectives() const
{
return _directives;
}
ResolverParams::ResolverParams(const SelectionSetParams& selectionSetParams,
const peg::ast_node& field, std::string&& fieldName, response::Value arguments,
Directives fieldDirectives, const peg::ast_node* selection, const FragmentMap& fragments,
const response::Value& variables)
: SelectionSetParams(selectionSetParams)
, field(field)
, fieldName(std::move(fieldName))
, arguments(std::move(arguments))
, fieldDirectives(std::move(fieldDirectives))
, selection(selection)
, fragments(fragments)
, variables(variables)
{
}
schema_location ResolverParams::getLocation() const
{
auto position = field.begin();
return { position.line, position.column };
}
template <>
int Argument<int>::convert(const response::Value& value)
{
if (value.type() != response::Type::Int)
{
throw schema_exception { { "not an integer" } };
}
return value.get<int>();
}
template <>
double Argument<double>::convert(const response::Value& value)
{
if (value.type() != response::Type::Float && value.type() != response::Type::Int)
{
throw schema_exception { { "not a float" } };
}
return value.get<double>();
}
template <>
std::string Argument<std::string>::convert(const response::Value& value)
{
if (value.type() != response::Type::String)
{
throw schema_exception { { "not a string" } };
}
return value.get<std::string>();
}
template <>
bool Argument<bool>::convert(const response::Value& value)
{
if (value.type() != response::Type::Boolean)
{
throw schema_exception { { "not a boolean" } };
}
return value.get<bool>();
}
template <>
response::Value Argument<response::Value>::convert(const response::Value& value)
{
return response::Value(value);
}
template <>
response::IdType Argument<response::IdType>::convert(const response::Value& value)
{
if (!value.maybe_id())
{
throw schema_exception { { "not an ID" } };
}
return response::Value { value }.release<response::IdType>();
}
void blockSubFields(const ResolverParams& params)
{
// https://spec.graphql.org/October2021/#sec-Leaf-Field-Selections
if (params.selection != nullptr)
{
auto position = params.selection->begin();
std::ostringstream error;
error << "Field may not have sub-fields name: " << params.fieldName;
throw schema_exception { { schema_error { error.str(),
{ position.line, position.column },
buildErrorPath(params.errorPath) } } };
}
}
template <>
AwaitableResolver Result<int>::convert(AwaitableScalar<int> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<int>::resolve(std::move(result),
std::move(params),
[](int&& value, const ResolverParams&) {
return response::Value(value);
});
}
template <>
AwaitableResolver Result<double>::convert(AwaitableScalar<double> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<double>::resolve(std::move(result),
std::move(params),
[](double&& value, const ResolverParams&) {
return response::Value(value);
});
}
template <>
AwaitableResolver Result<std::string>::convert(
AwaitableScalar<std::string> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<std::string>::resolve(std::move(result),
std::move(params),
[](std::string&& value, const ResolverParams&) {
return response::Value(std::move(value));
});
}
template <>
AwaitableResolver Result<bool>::convert(AwaitableScalar<bool> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<bool>::resolve(std::move(result),
std::move(params),
[](bool&& value, const ResolverParams&) {
return response::Value(value);
});
}
template <>
AwaitableResolver Result<response::Value>::convert(
AwaitableScalar<response::Value> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<response::Value>::resolve(std::move(result),
std::move(params),
[](response::Value&& value, const ResolverParams&) {
return response::Value(std::move(value));
});
}
template <>
AwaitableResolver Result<response::IdType>::convert(
AwaitableScalar<response::IdType> result, ResolverParams params)
{
blockSubFields(params);
return ModifiedResult<response::IdType>::resolve(std::move(result),
std::move(params),
[](response::IdType&& value, const ResolverParams&) {
return response::Value(std::move(value));
});
}
void requireSubFields(const ResolverParams& params)
{
// https://spec.graphql.org/October2021/#sec-Leaf-Field-Selections
if (params.selection == nullptr)
{
auto position = params.field.begin();
std::ostringstream error;
error << "Field must have sub-fields name: " << params.fieldName;
throw schema_exception { { schema_error { error.str(),
{ position.line, position.column },
buildErrorPath(params.errorPath) } } };
}
}
template <>
AwaitableResolver Result<Object>::convert(
AwaitableObject<std::shared_ptr<const Object>> result, ResolverParams params)
{
requireSubFields(params);
co_await params.launch;
auto awaitedResult = co_await std::move(result);
if (!awaitedResult)
{
co_return ResolverResult {};
}
auto document = co_await awaitedResult->resolve(params,
*params.selection,
params.fragments,
params.variables);
co_return std::move(document);
}
template <>
void Result<int>::validateScalar(const response::Value& value)
{
if (value.type() != response::Type::Int)
{
throw schema_exception { { R"ex(not a valid Int value)ex" } };
}
}
template <>
void Result<double>::validateScalar(const response::Value& value)
{
if (value.type() != response::Type::Float)
{
throw schema_exception { { R"ex(not a valid Float value)ex" } };
}
}
template <>
void Result<std::string>::validateScalar(const response::Value& value)
{
if (value.type() != response::Type::String)
{
throw schema_exception { { R"ex(not a valid String value)ex" } };
}
}
template <>
void Result<bool>::validateScalar(const response::Value& value)
{
if (value.type() != response::Type::Boolean)
{
throw schema_exception { { R"ex(not a valid Boolean value)ex" } };
}
}
template <>
void Result<response::IdType>::validateScalar(const response::Value& value)
{
if (!value.maybe_id())
{
throw schema_exception { { R"ex(not a valid ID value)ex" } };
}
}
template <>
void Result<response::Value>::validateScalar(const response::Value&)
{
// Any response::Value is valid for a custom scalar type.
}
// SelectionVisitor visits the AST and resolves a field or fragment, unless it's skipped by
// a directive or type condition.
class SelectionVisitor
{
public:
explicit SelectionVisitor(const SelectionSetParams& selectionSetParams,
const FragmentMap& fragments, const response::Value& variables, const TypeNames& typeNames,
const ResolverMap& resolvers, size_t count);
void visit(const peg::ast_node& selection);
std::vector<std::pair<std::string_view, AwaitableResolver>> getValues();
private:
void visitField(const peg::ast_node& field);
void visitFragmentSpread(const peg::ast_node& fragmentSpread);
void visitInlineFragment(const peg::ast_node& inlineFragment);
const ResolverContext _resolverContext;
const std::shared_ptr<RequestState>& _state;
const Directives& _operationDirectives;
const std::optional<std::reference_wrapper<const field_path>> _path;
const await_async _launch;
const FragmentMap& _fragments;
const response::Value& _variables;
const TypeNames& _typeNames;
const ResolverMap& _resolvers;
std::shared_ptr<FragmentDefinitionDirectiveStack> _fragmentDefinitionDirectives;
std::shared_ptr<FragmentSpreadDirectiveStack> _fragmentSpreadDirectives;
std::shared_ptr<FragmentSpreadDirectiveStack> _inlineFragmentDirectives;
internal::string_view_set _names;
std::vector<std::pair<std::string_view, AwaitableResolver>> _values;
};
SelectionVisitor::SelectionVisitor(const SelectionSetParams& selectionSetParams,
const FragmentMap& fragments, const response::Value& variables, const TypeNames& typeNames,
const ResolverMap& resolvers, size_t count)
: _resolverContext(selectionSetParams.resolverContext)
, _state(selectionSetParams.state)
, _operationDirectives(selectionSetParams.operationDirectives)
, _path(selectionSetParams.errorPath
? std::make_optional(std::cref(*selectionSetParams.errorPath))
: std::nullopt)
, _launch(selectionSetParams.launch)
, _fragments(fragments)
, _variables(variables)
, _typeNames(typeNames)
, _resolvers(resolvers)
, _fragmentDefinitionDirectives { selectionSetParams.fragmentDefinitionDirectives }
, _fragmentSpreadDirectives { selectionSetParams.fragmentSpreadDirectives }
, _inlineFragmentDirectives { selectionSetParams.inlineFragmentDirectives }
{
static const Directives s_emptyFragmentDefinitionDirectives;
// Traversing a SelectionSet from an Object type field should start tracking new fragment
// directives. The outer fragment directives are still there in the FragmentSpreadDirectiveStack
// if the field accessors want to inspect them.
_fragmentDefinitionDirectives->push_front(std::cref(s_emptyFragmentDefinitionDirectives));
_fragmentSpreadDirectives->push_front({});
_inlineFragmentDirectives->push_front({});
_names.reserve(count);
_values.reserve(count);
}
std::vector<std::pair<std::string_view, AwaitableResolver>> SelectionVisitor::getValues()
{
auto values = std::move(_values);
return values;
}
void SelectionVisitor::visit(const peg::ast_node& selection)
{
if (selection.is_type<peg::field>())
{
visitField(selection);
}
else if (selection.is_type<peg::fragment_spread>())
{
visitFragmentSpread(selection);
}
else if (selection.is_type<peg::inline_fragment>())
{
visitInlineFragment(selection);
}
}
void SelectionVisitor::visitField(const peg::ast_node& field)
{
std::string_view name;
peg::on_first_child<peg::field_name>(field, [&name](const peg::ast_node& child) {
name = child.string_view();
});
std::string_view alias;
peg::on_first_child<peg::alias_name>(field, [&alias](const peg::ast_node& child) {
alias = child.string_view();
});
if (alias.empty())
{
alias = name;
}
if (!_names.emplace(alias).second)
{
// Skip resolving fields which map to the same response name as a field we've already
// resolved. Validation should handle merging multiple references to the same field or
// to compatible fields.
return;
}
const auto itrResolver = _resolvers.find(name);
if (itrResolver == _resolvers.end())
{
std::promise<ResolverResult> promise;
auto position = field.begin();
std::ostringstream error;
error << "Unknown field name: " << name;
promise.set_exception(
std::make_exception_ptr(schema_exception { { schema_error { error.str(),
{ position.line, position.column },
buildErrorPath(_path ? std::make_optional(_path->get()) : std::nullopt) } } }));
_values.push_back({ alias, promise.get_future() });
return;
}
DirectiveVisitor directiveVisitor(_variables);
peg::on_first_child<peg::directives>(field, [&directiveVisitor](const peg::ast_node& child) {
directiveVisitor.visit(child);
});