Add a JSONSchema format or override an existing one #

JSON Schema object definition may have a “format” field, that specifies the semantic of the data. Along with the “type” field, it defines the data type more precisely. All formats supported by go-asyncapi out-of-the-box listed in features page.

Unknown JSONSchema formats, that are not built-in nor added as described below, are ignored.

The following example shows how to add a new custom format long for integer type.

For that define two following templates and put them to any file, say my_templates/long_integer.tmpl:

{{ define "code/lang/typeFormat/integer/long/definition" -}}
    int64
{{- end }}

{{ define "code/lang/typeFormat/integer/long/usage" -}}
    int64
{{- end }}

Then specify the template directory when generating the code:

go-asyncapi code --template-dir my_templates my_asyncapi.yml

Now, the following JSON Schema object will be rendered as int64 type in Go code:

type: integer
format: long

In most cases, it’s sufficient to leave the “usage” and “definition” templates identical, but sometimes you may want to make them different. For example, the format foobar of type object here is represented as a struct:

{{ define "code/lang/typeFormat/object/foobar/definition" -}}
    type {{goID .}} struct {
        Field1 string `json:"field1"`
        Field2 int    `json:"field2"`
    }
{{- end }}

{{ define "code/lang/typeFormat/object/foobar/usage" -}}
    {{ goPkg . }}{{ goID . }}
{{- end }}

Learn more about definition and usage code in templating guide.