quarkusio/quarkus · error · IllegalArgumentException

Only supported major versions are 0 and 1.

Error message

Only supported major versions are 0 and 1.

What it means

CloudEventBuilder.specVersion(String) validates the spec version string. Only major versions 0.x and 1.x are supported (per the CloudEvents spec); anything else (e.g. '2.0', 'abc', missing dot) throws IllegalArgumentException.

Source

Thrown at extensions/funqy/funqy-knative-events/runtime/src/main/java/io/quarkus/funqy/knative/events/CloudEventBuilder.java:26

    private String specVersion;
    private String id;
    private String type;
    private String source;
    private String subject;
    private OffsetDateTime time;
    private String dataSchema;
    private Map<String, String> extensions;

    private CloudEventBuilder() {
    }

    public static CloudEventBuilder create() {
        return new CloudEventBuilder();
    }

    public CloudEventBuilder specVersion(String specVersion) {
        if ((specVersion.charAt(0) != '0' && specVersion.charAt(0) != '1') || specVersion.charAt(1) != '.') {
            throw new IllegalArgumentException("Only supported major versions are 0 and 1.");
        }
        this.specVersion = specVersion;
        return this;
    }

    public CloudEventBuilder id(String id) {
        this.id = id;
        return this;
    }

    public CloudEventBuilder type(String type) {
        this.type = type;
        return this;
    }

    public CloudEventBuilder source(String source) {
        this.source = source;
        return this;

View on GitHub (pinned to e1c734241f)

Solutions

1. Use specVersion("1.0") (or "0.3" etc.) instead of the unsupported value.
2. Strip a leading 'v' prefix from the version string before passing it.
3. Upgrade the Quarkus Funqy extension if a newer CloudEvents spec version must be supported.
4. Validate/normalize incoming ce-specversion headers before dispatch.

Example fix

// before
CloudEventBuilder.create().specVersion("v1.0");
// after
CloudEventBuilder.create().specVersion("1.0");

boolean validSpecVersion(String v) { return v != null && v.length() >= 2 && (v.charAt(0)=='0'||v.charAt(0)=='1') && v.charAt(1)=='.'; }
if (!validSpecVersion(ver)) throw new IllegalArgumentException("Use 0.x or 1.x");

java.util.regex.Pattern CE_SPEC = Pattern.compile("^[01]\\.[0-9]+$");
boolean isSupportedSpec(String v) { return v != null && CE_SPEC.matcher(v).matches(); }

try { builder.specVersion(ver); } catch (IllegalArgumentException e) { log.warn("Unsupported ce-specversion: " + ver + ", defaulting to 1.0"); builder.specVersion("1.0"); }

When it happens

Trigger: Calling CloudEventBuilder.create().specVersion("...") with a string whose first char is not '0'/'1' or whose second char is not '.'; also triggered when an incoming Knative event header ce-specversion contains an unsupported value.

Common situations: Experimenting with a future CloudEvents spec version (e.g. 2.0), a typo like "1" or "v1.0", or an event source emitting an unsupported specversion header.

Related errors

• Don't know how to get event data (dataContentType: '%s', jav
• Cannot deserialize data for data-content-encoding: '${dataCo
• Don't know how to get event data (dataContentType: '%s', jav
• Function for trigger '${trigger}' has multiple matching invo
• When using CloudEvent<> generic parameter must be used.

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/464542db21e3f2d2. Report an issue: GitHub.