ion-cli

This repository is home to the ion command line tool, which provides subcommands for working with the Ion data format.

Table of contents

• Examples
  • Viewing the contents of an Ion file
  • Converting between Ion formats
  • Converting between Ion and other formats with to and from
  • Analyzing binary Ion file encodings with inspect
• Installation
  • via brew
  • via cargo
  • Installing experimental subcommand for code generation
• Build Instructions
  • From source
  • Using Docker

Examples

These examples use the .ion file extension for text Ion and the .10n file extension for binary Ion. This is simply a convention; the tool does not evaluate the file extension.

Unless otherwise noted, these commands can accept any Ion format as input.

Viewing the contents of an Ion file

The ion cat command reads the contents of the specified files (or STDIN) sequentially and writes their content to STDOUT in the requested Ion format.

ion cat my_file.ion

You can use the --format/-f flag to specify the desired format. The supported formats are:

• pretty - Generously spaced, human-friendly text Ion. This is the default.
• text - Minimally spaced text Ion.
• lines - Text Ion that places each value on its own line.
• binary- Binary Ion

Converting between Ion formats

Convert Ion text (or JSON) to Ion binary:

ion cat --format binary my_text_file.ion -o my_binary_file.ion 

Convert Ion binary to generously-spaced, human-friendly text:

ion cat --format pretty my_binary_file.ion -o my_text_file.ion 

Convert Ion binary to minimally-spaced, compact text:

ion cat --format text my_binary_file.ion -o my_text_file.ion 

Converting between Ion and other formats with to and from

The to and from commands can convert Ion to and from other formats. Currently, JSON is supported.

Convert Ion to JSON:

ion to -X json my_file.10n

Convert JSON to Ion:

ion from -X json my_file.json

Analyzing binary Ion file encodings with inspect

The inspect command can display the hex bytes of a binary Ion file alongside the equivalent text Ion for easier analysis.

# Write some text Ion to a file
echo '{foo: null, bar: true, baz: [1, 2, 3]}' > my_file.ion

# Convert the text Ion to binary Ion
ion cat --format binary my_file.ion > my_file.10n

# Show the binary encoding alongside its equivalent text 
ion inspect my_file.10n

The --skip-bytes flag

To skip to a particular offset in the stream, you can use the --skip-bytes flag.

ion inspect --skip-bytes 30 my_file.10n

Notice that the text column adds comments indicating where data has been skipped. Also, if the requested index is nested inside one or more containers, the beginnings of those containers (along with their lengths and offsets) will still be included in the output.

The --limit-bytes flag

You can limit the amount of data that inspect displays by using the --limit-bytes flag:

ion inspect --skip-bytes 30 --limit-bytes 2 my_file.10n

Schema subcommands

All the subcommand to load or validate schema are under the schema subcommand.

To load a schema:

ion schema -X load --directory <DIRECTORY> --schema <SCHEMA_FILE> 

To validate an ion value against a schema type:

ion schema -X validate --directory <DIRECTORY> --schema <SCHEMA_FILE> --input <INPUT_FILE> --type <TYPE>

For more information on how to use the schema subcommands using CLI, run the following command:

ion schema help  

Installation

via brew

The easiest way to install the ion-cli is via Homebrew.

Once the brew command is available, run:

brew tap amazon-ion/ion-cli
brew install ion-cli

via cargo

The ion-cli can also be installed by using Rust's package manager, cargo. If you don't already have cargo, you can install it by visiting rustup.rs.

To install ion-cli, run the following command:

cargo install ion-cli

Installing experimental subcommand for code generation

If you are looking into accessing all features with brew (including experimental features, currently only includes generate subcommand) of ion-cli, run:

brew install ion-cli --HEAD

If you are looking into accessing all features with cargo (including experimental features) of ion-cli, run:

cargo install ion-cli --all-features

Then make sure that ~/.cargo/bin is on your $PATH. You can confirm that it has been installed successfully by running:

ion help

You should see output that resembles the following:

A collection of tools for working with Ion data.

Usage: ion [OPTIONS] <COMMAND>

Commands:
  cat        Prints all Ion input files to the specified output in the requested format.
  count      (UNSTABLE) Prints the number of top-level values found in the input stream.
  from       'from' is a namespace for commands that convert other data formats to Ion.
  generate   (UNSTABLE) Generates code using given schema file.
  head       Prints the specified number of top-level values in the input stream.
  inspect    Displays hex-encoded binary Ion alongside its equivalent text Ion.
                 Its output prioritizes human readability and is likely to change
                 between versions. Stable output for programmatic use cases is a
                 non-goal.
  primitive  (UNSTABLE) Prints the binary representation of an Ion encoding primitive.
  schema     The 'schema' command is a namespace for commands that are related to Ion Schema.
  symtab     'symtab' is a namespace for commands that operate on symbol tables
  to         'to' is a namespace for commands that convert Ion to another data format.
  help       Print this message or the help of the given subcommand(s)

Options:
  -h, --help      Print help
  -V, --version   Print version
  -X, --unstable  Opt in to using an unstable feature of Ion CLI.

Build instructions

From source

1. Clone the repository:

   git clone https://github.com/amzn/ion-cli.git
   

2. Step into the newly created directory:

   cd ion-cli
   

3. Install Rust/Cargo by visiting rustup.rs.

4. Build the ion tool:

   cargo install --path .
   

   This will put a copy of the ion executable in ~/.cargo/bin.

5. Confirm that ~/.cargo/bin is on your $PATH. rustup will probably take care of this for you.

6. Confirm that the executable is available by running:

   ion help
   

Using Docker

1. Install Docker (see OS specific instructions on the Docker website)
2. Clone the repository (recursive clone not necessary)

   git clone https://github.com/amzn/ion-cli.git
   

3. Step into the newly created directory

   cd ion-cli
   

4. Build and run the image

   # build the image
   docker build -t <IMAGE_NAME>:<TAG> .
   
   
   # run the CLI binary inside the Docker image
   docker run -it --rm [optional flags...] <IMAGE_NAME>:<TAG> ion <SUBCOMMAND>
   
   # examples:
   
   # build docker image with current release version
   docker build -t ion-cli:0.1.1 .
   
   # print the help message
   docker run -it --rm ion-cli:0.1.1 ion -V
   
   # mount current directory to /data volume and cat an ion file
   docker run -it --rm -v $PWD:/data ion-cli:0.1.1 ion cat /data/test.ion
   
   

Security

See CONTRIBUTING for more information.

License

This project is licensed under the Apache-2.0 License.