Files
scylladb/cql3/functions/functions.hh
2015-01-14 17:12:08 +02:00

366 lines
14 KiB
C++

/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
/*
* Modified by Cloudius Systems
*
* Copyright 2015 Cloudius Systems
*/
#pragma once
#include "function.hh"
#include "aggregate_fcts.hh"
#include "time_uuid_fcts.hh"
#include "uuid_fcts.hh"
#include "bytes_conversion_fcts.hh"
#include "aggregate_fcts.hh"
#include "bytes_conversion_fcts.hh"
#include "cql3/assignment_testable.hh"
#include "cql3/cql3_type.hh"
#include <unordered_map>
namespace cql3 {
namespace functions {
#if 0
// We special case the token function because that's the only function whose argument types actually
// depend on the table on which the function is called. Because it's the sole exception, it's easier
// to handle it as a special case.
private static final FunctionName TOKEN_FUNCTION_NAME = FunctionName.nativeFunction("token");
#endif
class functions {
static thread_local std::unordered_multimap<function_name, shared_ptr<function>> _declared;
private:
static std::unordered_multimap<function_name, shared_ptr<function>> init() {
std::unordered_multimap<function_name, shared_ptr<function>> ret;
auto declare = [&ret] (shared_ptr<function> f) { ret.emplace(f->name(), std::move(f)); };
declare(aggregate_fcts::make_count_rows_function());
declare(time_uuid_fcts::make_now_fct());
declare(time_uuid_fcts::make_min_timeuuid_fct());
declare(time_uuid_fcts::make_max_timeuuid_fct());
declare(time_uuid_fcts::make_date_of_fct());
declare(time_uuid_fcts::make_unix_timestamp_of_fcf());
declare(make_uuid_fct());
for (auto&& type : native_cql3_type::values()) {
// Note: because text and varchar ends up being synonimous, our automatic makeToBlobFunction doesn't work
// for varchar, so we special case it below. We also skip blob for obvious reasons.
if (type == native_cql3_type::varchar || type == native_cql3_type::blob) {
continue;
}
declare(make_to_blob_function(type->get_type()));
declare(make_from_blob_function(type->get_type()));
}
declare(aggregate_fcts::make_count_function<int32_t>());
declare(aggregate_fcts::make_max_function<int32_t>());
declare(aggregate_fcts::make_min_function<int32_t>());
declare(aggregate_fcts::make_count_function<int64_t>());
declare(aggregate_fcts::make_max_function<int64_t>());
declare(aggregate_fcts::make_min_function<int64_t>());
//FIXME:
//declare(aggregate_fcts::make_count_function<bytes>());
//declare(aggregate_fcts::make_max_function<bytes>());
//declare(aggregate_fcts::make_min_function<bytes>());
// FIXME: more count/min/max
declare(make_varchar_as_blob_fct());
declare(make_blob_as_varchar_fct());
declare(aggregate_fcts::make_sum_function<int32_t>());
declare(aggregate_fcts::make_sum_function<int64_t>());
declare(aggregate_fcts::make_avg_function<int32_t>());
declare(aggregate_fcts::make_avg_function<int64_t>());
#if 0
declare(AggregateFcts.sumFunctionForFloat);
declare(AggregateFcts.sumFunctionForDouble);
declare(AggregateFcts.sumFunctionForDecimal);
declare(AggregateFcts.sumFunctionForVarint);
declare(AggregateFcts.avgFunctionForFloat);
declare(AggregateFcts.avgFunctionForDouble);
declare(AggregateFcts.avgFunctionForVarint);
declare(AggregateFcts.avgFunctionForDecimal);
#endif
// also needed for smp:
#if 0
MigrationManager.instance.register(new FunctionsMigrationListener());
#endif
return ret;
}
#if 0
public static ColumnSpecification makeArgSpec(String receiverKs, String receiverCf, Function fun, int i)
{
return new ColumnSpecification(receiverKs,
receiverCf,
new ColumnIdentifier("arg" + i + "(" + fun.name().toString().toLowerCase() + ")", true),
fun.argTypes().get(i));
}
#endif
static int get_overload_count(const function_name& name) {
return _declared.count(name);
}
static shared_ptr<function> get(const sstring& keyspace,
const function_name& name,
const std::vector<shared_ptr<assignment_testable>>& provided_args,
const sstring& receiver_ks,
const sstring& receiver_cf) {
#if 0
// later
if (name.has_keyspace()
? name.equals(TOKEN_FUNCTION_NAME)
: name.name.equals(TOKEN_FUNCTION_NAME.name))
return new TokenFct(Schema.instance.getCFMetaData(receiverKs, receiverCf));
List<Function> candidates;
if (!name.hasKeyspace())
{
// function name not fully qualified
candidates = new ArrayList<>();
// add 'SYSTEM' (native) candidates
candidates.addAll(declared.get(name.asNativeFunction()));
// add 'current keyspace' candidates
candidates.addAll(declared.get(new FunctionName(keyspace, name.name)));
}
else
// function name is fully qualified (keyspace + name)
candidates = declared.get(name);
if (candidates.isEmpty())
return null;
// Fast path if there is only one choice
if (candidates.size() == 1)
{
Function fun = candidates.get(0);
validateTypes(keyspace, fun, providedArgs, receiverKs, receiverCf);
return fun;
}
List<Function> compatibles = null;
for (Function toTest : candidates)
{
AssignmentTestable.TestResult r = matchAguments(keyspace, toTest, providedArgs, receiverKs, receiverCf);
switch (r)
{
case EXACT_MATCH:
// We always favor exact matches
return toTest;
case WEAKLY_ASSIGNABLE:
if (compatibles == null)
compatibles = new ArrayList<>();
compatibles.add(toTest);
break;
}
}
if (compatibles == null || compatibles.isEmpty())
throw new InvalidRequestException(String.format("Invalid call to function %s, none of its type signatures match (known type signatures: %s)",
name, toString(candidates)));
if (compatibles.size() > 1)
throw new InvalidRequestException(String.format("Ambiguous call to function %s (can be matched by following signatures: %s): use type casts to disambiguate",
name, toString(compatibles)));
return compatibles.get(0);
#endif
abort();
}
static std::vector<shared_ptr<function>> find(const function_name& name) {
auto range = _declared.equal_range(name);
std::vector<shared_ptr<function>> ret;
for (auto i = range.first; i != range.second; ++i) {
ret.push_back(i->second);
}
return ret;
}
static shared_ptr<function> find(const function_name& name, const std::vector<data_type>& arg_types) {
assert(name.has_keyspace()); // : "function name not fully qualified";
for (auto&& f : find(name)) {
if (type_equals(f->arg_types(), arg_types)) {
return f;
}
}
return {};
}
#if 0
// This method and matchArguments are somewhat duplicate, but this method allows us to provide more precise errors in the common
// case where there is no override for a given function. This is thus probably worth the minor code duplication.
private static void validateTypes(String keyspace,
Function fun,
List<? extends AssignmentTestable> providedArgs,
String receiverKs,
String receiverCf)
throws InvalidRequestException
{
if (providedArgs.size() != fun.argTypes().size())
throw new InvalidRequestException(String.format("Invalid number of arguments in call to function %s: %d required but %d provided", fun.name(), fun.argTypes().size(), providedArgs.size()));
for (int i = 0; i < providedArgs.size(); i++)
{
AssignmentTestable provided = providedArgs.get(i);
// If the concrete argument is a bind variables, it can have any type.
// We'll validate the actually provided value at execution time.
if (provided == null)
continue;
ColumnSpecification expected = makeArgSpec(receiverKs, receiverCf, fun, i);
if (!provided.testAssignment(keyspace, expected).isAssignable())
throw new InvalidRequestException(String.format("Type error: %s cannot be passed as argument %d of function %s of type %s", provided, i, fun.name(), expected.type.asCQL3Type()));
}
}
private static AssignmentTestable.TestResult matchAguments(String keyspace,
Function fun,
List<? extends AssignmentTestable> providedArgs,
String receiverKs,
String receiverCf)
{
if (providedArgs.size() != fun.argTypes().size())
return AssignmentTestable.TestResult.NOT_ASSIGNABLE;
// It's an exact match if all are exact match, but is not assignable as soon as any is non assignable.
AssignmentTestable.TestResult res = AssignmentTestable.TestResult.EXACT_MATCH;
for (int i = 0; i < providedArgs.size(); i++)
{
AssignmentTestable provided = providedArgs.get(i);
if (provided == null)
{
res = AssignmentTestable.TestResult.WEAKLY_ASSIGNABLE;
continue;
}
ColumnSpecification expected = makeArgSpec(receiverKs, receiverCf, fun, i);
AssignmentTestable.TestResult argRes = provided.testAssignment(keyspace, expected);
if (argRes == AssignmentTestable.TestResult.NOT_ASSIGNABLE)
return AssignmentTestable.TestResult.NOT_ASSIGNABLE;
if (argRes == AssignmentTestable.TestResult.WEAKLY_ASSIGNABLE)
res = AssignmentTestable.TestResult.WEAKLY_ASSIGNABLE;
}
return res;
}
private static String toString(List<Function> funs)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < funs.size(); i++)
{
if (i > 0) sb.append(", ");
sb.append(funs.get(i));
}
return sb.toString();
}
// This is *not* thread safe but is only called in SchemaTables that is synchronized.
public static void addFunction(AbstractFunction fun)
{
// We shouldn't get there unless that function don't exist
assert find(fun.name(), fun.argTypes()) == null;
declare(fun);
}
// Same remarks than for addFunction
public static void removeFunction(FunctionName name, List<AbstractType<?>> argsTypes)
{
Function old = find(name, argsTypes);
assert old != null && !old.isNative();
declared.remove(old.name(), old);
}
// Same remarks than for addFunction
public static void replaceFunction(AbstractFunction fun)
{
removeFunction(fun.name(), fun.argTypes());
addFunction(fun);
}
public static List<Function> getReferencesTo(Function old)
{
List<Function> references = new ArrayList<>();
for (Function function : declared.values())
if (function.hasReferenceTo(old))
references.add(function);
return references;
}
public static Collection<Function> all()
{
return declared.values();
}
public static boolean typeEquals(AbstractType<?> t1, AbstractType<?> t2)
{
return t1.asCQL3Type().toString().equals(t2.asCQL3Type().toString());
}
#endif
static bool type_equals(const std::vector<data_type>& t1, const std::vector<data_type>& t2) {
#if 0
if (t1.size() != t2.size())
return false;
for (int i = 0; i < t1.size(); i ++)
if (!typeEquals(t1.get(i), t2.get(i)))
return false;
return true;
#endif
abort();
}
#if 0
private static class FunctionsMigrationListener implements IMigrationListener
{
public void onCreateKeyspace(String ksName) { }
public void onCreateColumnFamily(String ksName, String cfName) { }
public void onCreateUserType(String ksName, String typeName) { }
public void onCreateFunction(String ksName, String functionName) { }
public void onCreateAggregate(String ksName, String aggregateName) { }
public void onUpdateKeyspace(String ksName) { }
public void onUpdateColumnFamily(String ksName, String cfName) { }
public void onUpdateUserType(String ksName, String typeName) {
for (Function function : all())
if (function instanceof UDFunction)
((UDFunction)function).userTypeUpdated(ksName, typeName);
}
public void onUpdateFunction(String ksName, String functionName) { }
public void onUpdateAggregate(String ksName, String aggregateName) { }
public void onDropKeyspace(String ksName) { }
public void onDropColumnFamily(String ksName, String cfName) { }
public void onDropUserType(String ksName, String typeName) { }
public void onDropFunction(String ksName, String functionName) { }
public void onDropAggregate(String ksName, String aggregateName) { }
}
#endif
};
}
}