rsonpath
– SIMD-powered JSONPath 🚀
Experimental JSONPath engine for querying massive streamed datasets.
Features
The rsonpath
crate provides a JSONPath parser and a query execution engine,
which utilizes SIMD instructions to provide massive throughput improvements over conventional engines.
Supported selectors
The project is actively developed and currently supports only a subset of the JSONPath query language.
Selector | Syntax | Supported | Since | |
---|---|---|---|---|
Root | $ |
✔️ | v0.1.0 | |
Dot | .<label> |
✔️ | v0.1.0 | |
Index (object member) | [<label>] |
✔️ | v0.1.0 | |
Index (array index) | [<index>] |
❌ | - | |
Descendant | .. |
✔️ | v0.1.0 | |
Child wildcard | .* , .[*] |
❌ | - | |
Descendant wildcard | ..* , ..[*] |
❌ | - | |
Slice | [<start>:<end>:<step>] |
❌ | - | |
List | [<sel1>, <sel2>, ..., <selN>] |
❌ | - | |
Filter | [?(<expr>)] |
❌ | - |
Installation
Easiest way to install is via cargo
.
This might fail with the following error:
Target architecture is not supported by SIMD features of this crate. Disable the default `simd` feature.
This means the SIMD features of the engine are not implemented for the machine's CPU.
You can still use rsonpath
, but the speed will be much more limited.
To install SIMD-less rsonpath
, run:
Alternatively, you can download the source code and manually run make install
.
Usage
To run a JSONPath query on a file execute:
If the file is omitted, the engine reads standard input.
For details, consult rsonpath --help
.
Results
The results are presented as an array of indices at which a colon of a matching record was found.
Alternatively, passing --result count
returns only the number of matches.
Engine
By default, the main SIMD engine is used. On machines not supporting SIMD, the recursive implementation
might be faster in some cases. To change the engine use --engine recursive
.
Build & test
Use the included Makefile
. It will automatically install Rust for you using the rustup
tool if it detects there is no Cargo in your environment.
Benchmarks
Benchmarks for rsonpath
are located in a separate repository,
included as a git submodule in this main repository.
Easiest way to run all the benchmarks is make bench
. For details, look at the README in the submodule.
Background
This project is the result of my thesis. You can read it for details on the theoretical background on the engine and details of its implementation.
Dependencies
Showing direct dependencies, for full graph see below.
rsonpath v0.1.2 (/home/mat/rsonpath/crates/rsonpath)
├── clap v4.0.25
├── color-eyre v0.6.2
├── eyre v0.6.8
├── log v0.4.17
├── rsonpath-lib v0.1.2
└── simple_logger v4.0.0
rsonpath-lib v0.1.2 (/home/mat/rsonpath/crates/rsonpath-lib)
├── aligners v0.0.10
├── cfg-if v1.0.0
├── log v0.4.17
├── memchr v2.5.0
├── nom v7.1.1
├── smallvec v1.10.0
├── thiserror v1.0.37
└── vector-map v1.0.1
Justification
-
clap
– standard crate to provide the CLI. -
color-eyre
,eyre
– more accessible error messages for the parser. -
log
,simple-logger
– diagnostic logs during compilation and execution. -
aligners
– SIMD operations require correct input data alignment, putting those requirements at type level makes our code more robust. -
cfg-if
– used to support SIMD and no-SIMD versions. -
memchr
– rapid, SIMDified substring search for fast-forwarding to labels. -
nom
– for parser implementation. -
smallvec
– crucial for small-stack performance. -
thiserror
– idiomaticError
implementations. -
vector_map
– used in the query compiler for measurably better performance.
Full dependency tree
rsonpath v0.1.2 (/home/mat/rsonpath/crates/rsonpath)
├── clap v4.0.25
│ ├── atty v0.2.14
│ │ └── libc v0.2.137
│ ├── bitflags v1.3.2
│ ├── clap_derive v4.0.21 (proc-macro)
│ │ ├── heck v0.4.0
│ │ ├── proc-macro-error v1.0.4
│ │ │ ├── proc-macro-error-attr v1.0.4 (proc-macro)
│ │ │ │ ├── proc-macro2 v1.0.47
│ │ │ │ │ └── unicode-ident v1.0.0
│ │ │ │ └── quote v1.0.18
│ │ │ │ └── proc-macro2 v1.0.47 (*)
│ │ │ ├── proc-macro2 v1.0.47 (*)
│ │ │ ├── quote v1.0.18 (*)
│ │ │ └── syn v1.0.75
│ │ │ ├── proc-macro2 v1.0.47 (*)
│ │ │ ├── quote v1.0.18 (*)
│ │ │ └── unicode-xid v0.2.2
│ │ ├── proc-macro2 v1.0.47 (*)
│ │ ├── quote v1.0.18 (*)
│ │ └── syn v1.0.75 (*)
│ ├── clap_lex v0.3.0
│ │ └── os_str_bytes v6.1.0
│ ├── once_cell v1.16.0
│ ├── strsim v0.10.0
│ ├── termcolor v1.1.3
│ └── terminal_size v0.2.2
│ └── rustix v0.35.13
│ ├── bitflags v1.3.2
│ ├── io-lifetimes v0.7.5
│ ├── libc v0.2.137
│ └── linux-raw-sys v0.0.46
├── color-eyre v0.6.2
│ ├── backtrace v0.3.65
│ │ ├── addr2line v0.17.0
│ │ │ └── gimli v0.26.1
│ │ ├── cfg-if v1.0.0
│ │ ├── libc v0.2.137
│ │ ├── miniz_oxide v0.5.1
│ │ │ └── adler v1.0.2
│ │ ├── object v0.28.3
│ │ │ └── memchr v2.5.0
│ │ └── rustc-demangle v0.1.21
│ ├── eyre v0.6.8
│ │ ├── indenter v0.3.3
│ │ └── once_cell v1.16.0
│ ├── indenter v0.3.3
│ ├── once_cell v1.16.0
│ └── owo-colors v3.3.0
├── eyre v0.6.8 (*)
├── log v0.4.17
│ └── cfg-if v1.0.0
├── rsonpath-lib v0.1.2 (/home/mat/rsonpath/crates/rsonpath-lib)
│ ├── aligners v0.0.10
│ │ ├── cfg-if v1.0.0
│ │ ├── lazy_static v1.4.0
│ │ └── page_size v0.4.2
│ │ └── libc v0.2.137
│ ├── cfg-if v1.0.0
│ ├── log v0.4.17 (*)
│ ├── memchr v2.5.0
│ ├── nom v7.1.1
│ │ ├── memchr v2.5.0
│ │ └── minimal-lexical v0.2.1
│ ├── smallvec v1.10.0
│ ├── thiserror v1.0.37
│ │ └── thiserror-impl v1.0.37 (proc-macro)
│ │ ├── proc-macro2 v1.0.47 (*)
│ │ ├── quote v1.0.18 (*)
│ │ └── syn v1.0.75 (*)
│ └── vector-map v1.0.1
│ ├── contracts v0.4.0 (proc-macro)
│ │ ├── proc-macro2 v1.0.47 (*)
│ │ ├── quote v1.0.18 (*)
│ │ └── syn v1.0.75 (*)
│ └── rand v0.7.3
│ ├── getrandom v0.1.16
│ │ ├── cfg-if v1.0.0
│ │ └── libc v0.2.137
│ ├── libc v0.2.137
│ ├── rand_chacha v0.2.2
│ │ ├── ppv-lite86 v0.2.16
│ │ └── rand_core v0.5.1
│ │ └── getrandom v0.1.16 (*)
│ └── rand_core v0.5.1 (*)
└── simple_logger v4.0.0
├── colored v2.0.0
│ ├── atty v0.2.14 (*)
│ └── lazy_static v1.4.0
├── log v0.4.17 (*)
└── time v0.3.17
├── itoa v1.0.2
├── libc v0.2.137
├── num_threads v0.1.6
├── time-core v0.1.0
└── time-macros v0.2.6 (proc-macro)
└── time-core v0.1.0