1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
#pragma once
#include <Compression/CompressionInfo.h>
#include <Compression/ICompressionCodec.h>
#include <DataTypes/IDataType.h>
#include <Parsers/IAST_fwd.h>
#include <Common/IFactoryWithAliases.h>
#include <functional>
#include <memory>
#include <optional>
#include <unordered_map>
namespace DB
{
static constexpr auto DEFAULT_CODEC_NAME = "Default";
class ICompressionCodec;
using CompressionCodecPtr = std::shared_ptr<ICompressionCodec>;
using CodecNameWithLevel = std::pair<String, std::optional<int>>;
/** Creates a codec object by name of compression algorithm family and parameters.
*/
class CompressionCodecFactory final : private boost::noncopyable
{
protected:
using Creator = std::function<CompressionCodecPtr(const ASTPtr & parameters)>;
using CreatorWithType = std::function<CompressionCodecPtr(const ASTPtr & parameters, const IDataType * column_type)>;
using SimpleCreator = std::function<CompressionCodecPtr()>;
using CompressionCodecsDictionary = std::unordered_map<String, CreatorWithType>;
using CompressionCodecsCodeDictionary = std::unordered_map<uint8_t, CreatorWithType>;
public:
static CompressionCodecFactory & instance();
/// Return default codec (currently LZ4)
CompressionCodecPtr getDefaultCodec() const;
/// Validate codecs AST specified by user and parses codecs description (substitute default parameters)
ASTPtr validateCodecAndGetPreprocessedAST(const ASTPtr & ast, const DataTypePtr & column_type, bool sanity_check, bool allow_experimental_codecs, bool enable_deflate_qpl_codec) const;
/// Validate codecs AST specified by user
void validateCodec(const String & family_name, std::optional<int> level, bool sanity_check, bool allow_experimental_codecs, bool enable_deflate_qpl_codec) const;
/// Get codec by AST and possible column_type. Some codecs can use
/// information about type to improve inner settings, but every codec should
/// be able to work without information about type. Also AST can contain
/// codec, which can be alias to current default codec, which can be changed
/// in runtime. If only_generic is true than method will filter all
/// isGenericCompression() == false codecs from result. If nothing found
/// will return codec NONE. It's useful for auxiliary parts of complex columns
/// like Nullable, Array and so on. If all codecs are non generic and
/// only_generic = true, than codec NONE will be returned.
CompressionCodecPtr get(const ASTPtr & ast, const IDataType * column_type, CompressionCodecPtr current_default = nullptr, bool only_generic = false) const;
/// Just wrapper for previous method.
CompressionCodecPtr get(const ASTPtr & ast, const DataTypePtr & column_type, CompressionCodecPtr current_default = nullptr, bool only_generic = false) const
{
return get(ast, column_type.get(), current_default, only_generic);
}
/// Get codec by method byte (no params available)
CompressionCodecPtr get(uint8_t byte_code) const;
/// For backward compatibility with config settings
CompressionCodecPtr get(const String & family_name, std::optional<int> level) const;
/// Register codec with parameters and column type
void registerCompressionCodecWithType(const String & family_name, std::optional<uint8_t> byte_code, CreatorWithType creator);
/// Register codec with parameters
void registerCompressionCodec(const String & family_name, std::optional<uint8_t> byte_code, Creator creator);
/// Register codec without parameters
void registerSimpleCompressionCodec(const String & family_name, std::optional<uint8_t> byte_code, SimpleCreator creator);
protected:
CompressionCodecPtr getImpl(const String & family_name, const ASTPtr & arguments, const IDataType * column_type) const;
private:
CompressionCodecsDictionary family_name_with_codec;
CompressionCodecsCodeDictionary family_code_with_codec;
CompressionCodecPtr default_codec;
CompressionCodecFactory();
};
}
|
