Ion (serialization format)

Last updated
Ion
Filename extension
.ion
Internet media type application/ion
Developed byAmazon
Type of formatData interchange
Website amzn.github.io/ion-docs/

Ion is a data serialization language developed by Amazon. It may be represented by either a human-readable text form or a compact binary form. The text form is a superset of JSON; thus, any valid JSON document is also a valid Ion document.

Contents

Data types

As a superset of JSON, Ion includes the following data types

The nebulous JSON 'number' type is strictly defined in Ion to be one of

Ion adds these types:

Each Ion type supports a null variant, indicating a lack of value while maintaining a strict type (e.g., null.int, null.struct).

The Ion format permits attaching one or more annotations (i.e. a list of symbols) to any value. Such annotations may be used as metadata for otherwise opaque data (such as a blob).

Implementations

Examples

Sample document

Features seen in JavaScript and JSON5:

// Comments are allowed using the double forward slash {key:"value",// key here is a symbol, it can also be a string as in JSONnums:1_000_000,// equivalent to 1000000, use of underscores with numbers is more readable"A float":31415e-4,// key is a value that contains spaces }

Features unique to Ion:

{symbol:'a symbol',// symbols are interned Unicode strings"A null integer":null.int,annotated:age::35,// the symbol "age" is attached to the value "35" as an annotationlists:'hw grades'::[80,85,90],// any symbol can be used as an annotation many_annot:I::have::many::annotations::true,// annotations are not nested, but rather, a list of annotationssexp:(this(isa[valid]"Ion")last::value+42)// Ion S-expressions. 'this', 'is', 'a', 'valid', 'value', and '+' are symbols._value:{{OiBTIKUgTyAASb8=}},// blob value is represented as base64_value:{{"a b\0\xff"}}// clob value is represented as an ASCII string with C-style escapes// ^ repeated names (keys) are allowed but generate a warning for undefined behavior }

Uses

Tooling and extensions

References

  1. ↑ "We are the Amazon Managed Blockchain and Amazon QLDB Teams – Ask the AWS Experts – November 29 @ 3PM PST / 6PM EST". 28 November 2018.
  2. ↑ "Announcing PartiQL: One query language for all your data". August 2019.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.