warp-wasm-json-toolkit
Version:
Warp implementation of wasm-json-toolkit
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# SYNOPSIS
[](https://www.npmjs.org/package/wasm-json-toolkit)
[](https://travis-ci.org/ewasm/wasm-json-toolkit)
[](https://coveralls.io/r/ewasm/wasm-json-toolkit)
[](https://github.com/feross/standard)
warp-wasm-json-toolkit is a fork of https://github.com/ewasm/wasm-json-toolkit which provides consistent API for Buffer object between server and client by using `safe-buffer` library for node and `buffer` for browser.
A small toolkit for converting wasm binaries into json and back.
# INSTALL
`npm install warp-wasm-json-toolkit`
# USAGE
```javascript
const fs = require('fs');
const wasm2json = require('warp-wasm-json-toolkit').wasm2json;
const wasm = fs.readFileSync('./test.wasm');
const json = wasm2json(wasm);
console.log(JSON.stringify(json, null, 2));
```
# CLI
Install `-g` global for cli usage.
`wasm2json [FILE]` given a file containing a wasm module produces a json representation
`json2wasm [FILE]` given a file containing a json representation produces a wasm module
# API
# wasm2json
converts a wasm binary into a json representation
**Parameters**
- `Buffer` - The Webassembly Binary
- `filter` - `Set` containing the name of sections to parse. If no filter is given all sections will be parsed
Returns **[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)**
# json2wasm
converts a json representation to a wasm binary
**Parameters**
- `Object`
Returns **[Buffer](https://nodejs.org/api/buffer.html)**
# text2json
converts text to json. The only text accepted is a simple list of opcode name and immediates
**Parameters**
- `String`
**Examples**
```javascript
const codeStr = `
i64.const 1
i64.const 2
i64.add
`;
const json = text2json(codeStr);
```
Returns **[Object](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object)**
# iterator
[iterator.js:12-58](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L12-L58 'Source code on GitHub')
The Module Iterator allows for iteration over a webassembly module's sections.
A section is wrapped in a section class. A section class instance allows you
append entries to a given section
**Examples**
```javascript
const it = new Iterator(wasm);
for (const section of it) {
console.log(section.type);
const json = section.toJSON();
}
```
## wasm
[iterator.js:26-32](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L26-L32 'Source code on GitHub')
if the orignal wasm module was modified then this will return the modified
wasm module
## iterator
[iterator.js:38-52](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L38-L52 'Source code on GitHub')
Iterates through the module's sections
return {Iterator.<Section>}
# Section
[iterator.js:64-110](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L64-L110 'Source code on GitHub')
The section class is always internal created by the Module class. And return
through the Module's iternator
## toJSON
[iterator.js:83-85](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L83-L85 'Source code on GitHub')
Parses the section and return the JSON repesentation of it
returns {Object}
## appendEntries
[iterator.js:92-109](https://github.com/ewasm/wasm-json-toolkit/blob/e9fdd9498451b39b84c1167e78dc4aad03b055bd/iterator.js#L92-L109 'Source code on GitHub')
Appends an array of entries to this section. NOTE: this will modify the
parent wasm module.
**Parameters**
- `entries` **Arrayy<[Buffer](https://nodejs.org/api/buffer.html)>**
## exammple json output
wast
```
(module
(func $addTwo (param i32 i32) (result i32)
(i32.add
(get_local 0)
(get_local 1)))
(export "addTwo" (func $addTwo)))
```
wasm
```
0x010661646454776f00000a09010700200020016a0b
```
json
```
[
{
"name": "preramble",
"magic": [0,97,115,109],
"version": [13,0,0,0]
},
{
"name": "type",
"entries": [
{
"form": "func",
"params": ["i32","i32"],
"return_type": "i32"
}
]
},
{
"name": "function",
"entries": [0]
},
{
"name": "export",
"entries": [
{
"field_str": "addTwo",
"kind": "Function",
"index": 0
}
]
},
{
"name": "code",
"entries": [
{
"locals": [],
"code": [
{
"name": "get_local",
"immediaties": "0"
},
{
"name": "get_local",
"immediaties": "1"
},
{
"return_type": "i32",
"name": "add"
},
{
"name": "end"
}
]
}
]
}
]
```
# LICENSE
[MPL-2.0][license]
[license]: https://tldrlegal.com/license/mozilla-public-license-2.0-(mpl-2)