curlconverter

Transpile curl commands into Python, JavaScript, Java, C#, PHP, Go, Dart, R, Ruby, Rust, MATLAB, Elixir, CFML, Ansible or JSON.

Try it on curlconverter.com or from the command line as a drop-in replacement for curl:

$ curlconverter --data "hello=world" example.com
import requests

data = {
    'hello': 'world',
}

response = requests.post('http://example.com', data=data)

Features:

• Knows about all of curl's 300 or so arguments, including deleted ones, but most are ignored
• Supports multiple short arguments passed as one, for example -OvXPOST instead of -O -v -X POST
• Converts JSON to native objects
• Understands most Bash syntax
  • ANSI-C quoted strings (which "Copy as cURL" can output)
  • Piped file or input (such as heredocs)
  • Generated code reads environment variables and runs subcommands at runtime
  • Ignores comments
  • Reports syntax errors
• Warns about issues with the conversion

Python-only features (mostly):

• --data @filename generates code that reads from that file
• --data @- generates code that reads from stdin (or piped file/input)

Limitations:

• Only HTTP is supported
• Code generators for other languages are less thorough than the Python generator
• By default, curl doesn't follow redirects or decompress gzip-compressed responses but the generated code will do whatever the default is for that runtime, to keep it simpler. For example Python's Requests library follows redirects by default, so unless you explicitly set the redirect policy with -L/--location/--no-location, the resulting code will not do what curl would do if the server responds with a redirect
• the contents of shell variables can usually arbitrarily change how the command would be parsed at runtime. For example, in a command like curl example.com?foo=bar&baz=$VAR, if $VAR contains = or & characters or percent encoded characters, that could make the generated code wrong. The code assumes that environment variables don't contain significant characters
• only simple subcommands such as curl $(echo example.com) work, more complicated subcommands (such as nested commands or subcommands that redirect the output) won't generate valid code
• and much more

Install

Install the command line tool with

npm install --global curlconverter

Install the JavaScript library for use in your own projects with

npm install curlconverter

curlconverter requires Node 14+.

Usage

Usage from the command line

The command line tool is a drop-in replacement for curl. Take any curl command, change "curl" to "curlconverter" and it will print code instead of making the request

$ curlconverter example.com
import requests

response = requests.get('http://example.com')

or you can pass - to tell it to read the curl command from stdin

$ echo 'curl example.com' | curlconverter -
import requests

response = requests.get('http://example.com')

You can choose the output language by passing --language <language>. The options are

• ansible
• cfml
• csharp
• dart
• elixir
• go
• java
• javascript, node, node-axios, node-got, node-request
• json
• matlab
• php, php-request
• python (the default)
• r
• ruby
• rust

Usage as a library

The JavaScript API is a bunch of functions that can take either a string of Bash code or an array of already-parsed arguments (like process.argv) and return a string with the resulting program:

import * as curlconverter from 'curlconverter';

curlconverter.toPython('curl example.com');
curlconverter.toPython(['curl', 'example.com']);
// "import requests\n\nresponse = requests.get('http://example.com')\n"

Note: add "type": "module" to your package.json for the import statement above to work.

There's a corresponding set of functions that also return an array of warnings if there are any issues with the conversion:

curlconverter.toPythonWarn('curl ftp://example.com');
curlconverter.toPythonWarn(['curl', 'ftp://example.com']);
// [
//   "import requests\n\nresponse = requests.get('ftp://example.com')\n",
//   [ [ 'bad-scheme', 'Protocol "ftp" not supported' ] ]
// ]

If you want to host curlconverter yourself and use it in the browser, it needs two WASM files to work, tree-sitter.wasm and tree-sitter-bash.wasm, which it will request from the root directory of your web server. If you are hosting a static website and using Webpack, you need to copy these files from the node_modules/ directory to your server's root directory in order to serve them. You can look at the webpack.config.js for curlconverter.com to see how this is done. You will also need to set {module: {experiments: {topLevelAwait: true}}} in your webpack.config.js.

Usage in VS Code

There's a VS Code extension that adds a "Paste cURL as <language>" option to the right-click menu: https://marketplace.visualstudio.com/items?itemName=curlconverter.curlconverter. It has to use an old version of curlconverter, so it doesn't support the same languages, curl arguments or Bash syntax as the current version.

Contributing

See CONTRIBUTING.md

License

MIT © Nick Carneiro