return ErrInvalidToken
	}

	// Verify finally if signature is same.

	// Get canonical request.
	presignedCanonicalReq := getCanonicalRequest(extractedSignedHeaders, hashedPayload, encodedQuery, req.URL.Path, req.Method)

	// Get string to sign from canonical request.
	presignedStringToSign := getStringToSign(presignedCanonicalReq, t, pSignValues.Credential.getScope())

canonicalizing values (like "interning" or "hash-consing").

Any value of comparable type may be canonicalized with the new
`Make[T]` function, which produces a reference to a canonical copy of
the value in the form of a `Handle[T]`.
Two `Handle[T]` are equal if and only if the values used to produce the
handles are equal, allowing programs to deduplicate values and reduce
their memory footprint.

{{- if eq .Release.Namespace "istio-system"}}
        heritage: Tiller
        release: istio
        chart: gateways
{{- end }}
        service.istio.io/canonical-name: {{ $gateway.name }}
        service.istio.io/canonical-revision: {{ index $gateway.labels "app.kubernetes.io/version" | default (index $gateway.labels "version") | default .Values.revision | default "latest" | quote }}

import org.apache.maven.api.services.ModelBuilderRequest;
import org.apache.maven.api.services.ModelProblemCollector;

/**
 * Handles normalization of a model. In this context, normalization is the process of producing a canonical
 * representation for models that physically look different but are semantically equivalent.
 *
 */
public interface ModelNormalizer {

    /**

	stdPackages []string                     // names, omitting "unsafe", internal, and vendored packages
	importMap   map[string]map[string]string // importer dir -> import path -> canonical path
	importDir   map[string]string            // canonical import path -> dir

}

func NewWalker(context *build.Context, root string) *Walker {
	w := &Walker{
		context:  context,
		root:     root,
		features: map[string]bool{},

{{- if eq .Release.Namespace "istio-system"}}
        heritage: Tiller
        release: istio
        chart: gateways
{{- end }}
        service.istio.io/canonical-name: {{ $gateway.name }}
        service.istio.io/canonical-revision: {{ index $gateway.labels "app.kubernetes.io/version" | default (index $gateway.labels "version") | default .Values.revision | default "latest" | quote }}

	md := meshConfig.DefaultConfig.ProxyMetadata
	if md == nil {
		md = map[string]string{}
		meshConfig.DefaultConfig.ProxyMetadata = md
	}
	md["CANONICAL_SERVICE"], md["CANONICAL_REVISION"] = labels.CanonicalService(lbls, wg.Name)
	md["POD_NAMESPACE"] = wg.Namespace
	md["SERVICE_ACCOUNT"] = we.ServiceAccount
	md["TRUST_DOMAIN"] = meshConfig.TrustDomain

                return rx - lx;
            } else {
                return lx - rx;
            }
        };

        Map<String, Lifecycle> lifecyclesMap = lookupLifecycles();

        // ensure canonical order of standard lifecycles
        return lifecyclesMap.values().stream()
                .peek(l -> Objects.requireNonNull(l.getId(), "A lifecycle must have an id."))

	var condPassed bool

	// Iterate over policy conditions and check them against received form fields
	for _, policy := range postPolicyForm.Conditions.Policies {
		// Form fields names are in canonical format, convert conditions names
		// to canonical for simplification purpose, so `$key` will become `Key`
		formCanonicalName := http.CanonicalHeaderKey(strings.TrimPrefix(policy.Key, "$"))
		// Operator for the current policy condition

    checkNotNull(domain);
    if (isEmpty()) {
      return ImmutableSortedSet.of();
    }
    Range<C> span = span().canonical(domain);
    if (!span.hasLowerBound()) {
      // according to the spec of canonical, neither this ImmutableRangeSet nor
      // the range have a lower bound
      throw new IllegalArgumentException(