Examples with ITemplateContext org.thymeleaf.context.ITemplateContext used on opensource projects

Example 1 with ITemplateContext

use of org.thymeleaf.context.ITemplateContext in project thymeleaf by thymeleaf.

the class MessageExpression method executeMessageExpression.

static Object executeMessageExpression(final IExpressionContext context, final MessageExpression expression, final StandardExpressionExecutionContext expContext) {
    if (logger.isTraceEnabled()) {
        logger.trace("[THYMELEAF][{}] Evaluating message: \"{}\"", TemplateEngine.threadIndex(), expression.getStringRepresentation());
    }
    if (!(context instanceof ITemplateContext)) {
        throw new TemplateProcessingException("Cannot evaluate expression \"" + expression + "\". Message externalization expressions " + "can only be evaluated in a template-processing environment (as a part of an in-template expression) " + "where processing context is an implementation of " + ITemplateContext.class.getClass() + ", which it isn't (" + context.getClass().getName() + ")");
    }
    final ITemplateContext templateContext = (ITemplateContext) context;
    final IStandardExpression baseExpression = expression.getBase();
    Object messageKey = baseExpression.execute(templateContext, expContext);
    messageKey = LiteralValue.unwrap(messageKey);
    if (messageKey != null && !(messageKey instanceof String)) {
        messageKey = messageKey.toString();
    }
    if (StringUtils.isEmptyOrWhitespace((String) messageKey)) {
        throw new TemplateProcessingException("Message key for message resolution must be a non-null and non-empty String");
    }
    final Object[] messageParameters;
    if (expression.hasParameters()) {
        final ExpressionSequence parameterExpressionSequence = expression.getParameters();
        final List<IStandardExpression> parameterExpressionValues = parameterExpressionSequence.getExpressions();
        final int parameterExpressionValuesLen = parameterExpressionValues.size();
        messageParameters = new Object[parameterExpressionValuesLen];
        for (int i = 0; i < parameterExpressionValuesLen; i++) {
            final IStandardExpression parameterExpression = parameterExpressionValues.get(i);
            final Object result = parameterExpression.execute(templateContext, expContext);
            messageParameters[i] = LiteralValue.unwrap(result);
        }
    } else {
        messageParameters = NO_PARAMETERS;
    }
    // Note message expressions will always return an absent representation if message does not exist
    return templateContext.getMessage(null, (String) messageKey, messageParameters, true);
}

Example 2 with ITemplateContext

use of org.thymeleaf.context.ITemplateContext in project thymeleaf by thymeleaf.

the class LinkExpression method executeLinkExpression.

static Object executeLinkExpression(final IExpressionContext context, final LinkExpression expression) {
    if (logger.isTraceEnabled()) {
        logger.trace("[THYMELEAF][{}] Evaluating link: \"{}\"", TemplateEngine.threadIndex(), expression.getStringRepresentation());
    }
    if (!(context instanceof ITemplateContext)) {
        throw new TemplateProcessingException("Cannot evaluate expression \"" + expression + "\". Link expressions " + "can only be evaluated in a template-processing environment (as a part of an in-template expression) " + "where processing context is an implementation of " + ITemplateContext.class.getClass() + ", which it isn't (" + context.getClass().getName() + ")");
    }
    final ITemplateContext templateContext = (ITemplateContext) context;
    final IStandardExpression baseExpression = expression.getBase();
    // The URL base in a link expression will always be executed in RESTRICTED mode, so we will forbid that
    // base URLs come directly from user input (request parameters). Note this restriction does not need to apply
    // to URL parameters.
    Object base = baseExpression.execute(templateContext, StandardExpressionExecutionContext.RESTRICTED);
    base = LiteralValue.unwrap(base);
    if (base != null && !(base instanceof String)) {
        base = base.toString();
    }
    if (base == null || StringUtils.isEmptyOrWhitespace((String) base)) {
        base = "";
    }
    /*
         * Resolve the parameters from the expression into a LinkParameters object.
         * Note the parameters variable might be null if there are no parameters
         *
         * Also note that link parameters, which should be correctly URL-encoded before being added to
         * the query string of the URL, will always be executed using UNRESTRICTED mode, so that request
         * params can be directly passed along to other generated URLs.
         */
    final Map<String, Object> parameters = resolveParameters(templateContext, expression, StandardExpressionExecutionContext.NORMAL);
    return templateContext.buildLink((String) base, parameters);
}

Example 3 with ITemplateContext

use of org.thymeleaf.context.ITemplateContext in project thymeleaf by thymeleaf.

the class OGNLVariableExpressionEvaluator method evaluate.

private static Object evaluate(final IExpressionContext context, final IStandardVariableExpression expression, final StandardExpressionExecutionContext expContext, final boolean applyOGNLShortcuts) {
    try {
        if (logger.isTraceEnabled()) {
            logger.trace("[THYMELEAF][{}] OGNL expression: evaluating expression \"{}\" on target", TemplateEngine.threadIndex(), expression.getExpression());
        }
        final IEngineConfiguration configuration = context.getConfiguration();
        final String exp = expression.getExpression();
        final boolean useSelectionAsRoot = expression.getUseSelectionAsRoot();
        if (exp == null) {
            throw new TemplateProcessingException("Expression content is null, which is not allowed");
        }
        final ComputedOGNLExpression parsedExpression = obtainComputedOGNLExpression(configuration, expression, exp, applyOGNLShortcuts);
        final Map<String, Object> contextVariablesMap;
        if (parsedExpression.mightNeedExpressionObjects) {
            // The IExpressionObjects implementation returned by processing contexts that include the Standard
            // Dialects will be lazy in the creation of expression objects (i.e. they won't be created until really
            // needed). And in order for this behaviour to be accepted by OGNL, we will be wrapping this object
            // inside an implementation of Map<String,Object>, which will afterwards be fed to the constructor
            // of an OgnlContext object.
            // Note this will never happen with shortcut expressions, as the '#' character with which all
            // expression object names start is not allowed by the OGNLShortcutExpression parser.
            final IExpressionObjects expressionObjects = context.getExpressionObjects();
            contextVariablesMap = new OGNLExpressionObjectsWrapper(expressionObjects, expContext.getRestrictVariableAccess());
            // can later lookup during evaluation.
            if (expContext.getRestrictVariableAccess()) {
                contextVariablesMap.put(OGNLContextPropertyAccessor.RESTRICT_REQUEST_PARAMETERS, OGNLContextPropertyAccessor.RESTRICT_REQUEST_PARAMETERS);
            } else {
                contextVariablesMap.remove(OGNLContextPropertyAccessor.RESTRICT_REQUEST_PARAMETERS);
            }
        } else {
            if (expContext.getRestrictVariableAccess()) {
                contextVariablesMap = CONTEXT_VARIABLES_MAP_NOEXPOBJECTS_RESTRICTIONS;
            } else {
                contextVariablesMap = Collections.EMPTY_MAP;
            }
        }
        // The root object on which we will evaluate expressions will depend on whether a selection target is
        // active or not...
        final ITemplateContext templateContext = (context instanceof ITemplateContext ? (ITemplateContext) context : null);
        final Object evaluationRoot = (useSelectionAsRoot && templateContext != null && templateContext.hasSelectionTarget() ? templateContext.getSelectionTarget() : templateContext);
        // Execute the expression!
        final Object result;
        try {
            result = executeExpression(configuration, parsedExpression.expression, contextVariablesMap, evaluationRoot);
        } catch (final OGNLShortcutExpression.OGNLShortcutExpressionNotApplicableException notApplicable) {
            // We tried to apply shortcuts, but it is not possible for this expression even if it parsed OK,
            // so we need to empty the cache and try again disabling shortcuts. Once processed for the first time,
            // an OGNL (non-shortcut) parsed expression will already be cached and this exception will not be
            // thrown again
            invalidateComputedOGNLExpression(configuration, expression, exp);
            return evaluate(context, expression, expContext, false);
        }
        if (!expContext.getPerformTypeConversion()) {
            return result;
        }
        final IStandardConversionService conversionService = StandardExpressions.getConversionService(configuration);
        return conversionService.convert(context, result, String.class);
    } catch (final Exception e) {
        throw new TemplateProcessingException("Exception evaluating OGNL expression: \"" + expression.getExpression() + "\"", e);
    }
}

Example 4 with ITemplateContext

use of org.thymeleaf.context.ITemplateContext in project thymeleaf by thymeleaf.

the class AbstractStandardFragmentInsertionTagProcessor method doProcess.

@Override
protected void doProcess(final ITemplateContext context, final IProcessableElementTag tag, final AttributeName attributeName, final String attributeValue, final IElementTagStructureHandler structureHandler) {
    if (StringUtils.isEmptyOrWhitespace(attributeValue)) {
        throw new TemplateProcessingException("Fragment specifications cannot be empty");
    }
    final IEngineConfiguration configuration = context.getConfiguration();
    /*
         * PARSE AND PROCESS THE FRAGMENT
         */
    final Object fragmentObj = computeFragment(context, attributeValue);
    if (fragmentObj == null) {
        throw new TemplateInputException("Error resolving fragment: \"" + attributeValue + "\": " + "template or fragment could not be resolved");
    } else if (fragmentObj == NoOpToken.VALUE) {
        // If the Fragment result is NO-OP, we will just do nothing (apart from deleting the th:* attribute)
        return;
    } else if (fragmentObj == Fragment.EMPTY_FRAGMENT) {
        // tag (th:insert) or remove it completely, tag included (th:replace)
        if (this.replaceHost) {
            structureHandler.removeElement();
        } else {
            structureHandler.removeBody();
        }
        return;
    }
    final Fragment fragment = (Fragment) fragmentObj;
    final TemplateModel fragmentModel = fragment.getTemplateModel();
    Map<String, Object> fragmentParameters = fragment.getParameters();
    /*
         * ONCE WE HAVE THE FRAGMENT MODEL (its events, in fact), CHECK THE FRAGMENT SIGNATURE
         * Fragment signature is important because it might affect the way we apply the parameters to the fragment.
         *
         * Note this works whatever the template mode of the inserted fragment, given we are looking for an
         * element containing a "th:fragment/data-th-fragment" in a generic, non-template-dependent way.
         */
    // We will check types first instead of events in order to (many times) avoid creating an immutably-wrapped
    // event object when calling "model.get(pos)"
    boolean signatureApplied = false;
    final ITemplateEvent firstEvent = (fragmentModel.size() > 2 ? fragmentModel.get(1) : null);
    if (firstEvent != null && IProcessableElementTag.class.isAssignableFrom(firstEvent.getClass())) {
        final String dialectPrefix = attributeName.getPrefix();
        final IProcessableElementTag fragmentHolderEvent = (IProcessableElementTag) firstEvent;
        if (fragmentHolderEvent.hasAttribute(dialectPrefix, FRAGMENT_ATTR_NAME)) {
            // The selected fragment actually has a "th:fragment" attribute, so we should process its signature
            final String fragmentSignatureSpec = EscapedAttributeUtils.unescapeAttribute(fragmentModel.getTemplateMode(), fragmentHolderEvent.getAttributeValue(dialectPrefix, FRAGMENT_ATTR_NAME));
            if (!StringUtils.isEmptyOrWhitespace(fragmentSignatureSpec)) {
                final FragmentSignature fragmentSignature = FragmentSignatureUtils.parseFragmentSignature(configuration, fragmentSignatureSpec);
                if (fragmentSignature != null) {
                    // Reshape the fragment parameters into the ones that we will actually use, according to the signature
                    fragmentParameters = FragmentSignatureUtils.processParameters(fragmentSignature, fragmentParameters, fragment.hasSyntheticParameters());
                    signatureApplied = true;
                }
            }
        }
    }
    // not being applied, maybe not realising there was no signature assignation involved.
    if (!signatureApplied && fragment.hasSyntheticParameters()) {
        throw new TemplateProcessingException("Fragment '" + attributeValue + "' specifies synthetic (unnamed) parameters, but the resolved fragment " + "does not match a fragment signature (th:fragment,data-th-fragment) which could apply names to " + "the specified parameters.");
    }
    /*
         * CHECK WHETHER THIS IS A CROSS-TEMPLATE-MODE INSERTION. Only TemplateModels for the same template mode
         * can be safely inserted into the template being executed and processed just like any other sequences of
         * events. If the inserted template has a different template mode, we will need to process it aside and
         * obtain a String result for it, then insert such String as mere text.
         *
         * Note inserting large templates with a different template mode could therefore have a negative effect
         * on performance and memory usage, as their result needs to be completely stored in memory at some point
         * before being handled to the following phases of template processing. It is therefore recommended that
         * cross-template-mode fragment insertion is done only for small fragments, in which case it will work
         * almost the same as inlining (with the exception that the content to be inlined will be retrieved from
         * somewhere else by means of template resolution).
         */
    if (context.getTemplateMode() != fragmentModel.getTemplateMode()) {
        // Check if this is a th:include. If so, just don't allow
        if (this.insertOnlyContents) {
            throw new TemplateProcessingException("Template being processed uses template mode " + context.getTemplateMode() + ", " + "inserted fragment \"" + attributeValue + "\" uses template mode " + fragmentModel.getTemplateMode() + ". Cross-template-mode fragment insertion is not " + "allowed using the " + attributeName + " attribute, which is no longer recommended for use as " + "of Thymeleaf 3.0. Use {th:insert,data-th-insert} or {th:replace,data-th-replace} " + "instead, which do not remove the container element from the fragment being inserted.");
        }
        // doing it through the structure handler (we are going to perform a nested template processing operation)
        if (fragmentParameters != null && fragmentParameters.size() > 0) {
            if (!(context instanceof IEngineContext)) {
                throw new TemplateProcessingException("Parameterized fragment insertion is not supported because local variable support is DISABLED. This is due to " + "the use of an implementation of the " + ITemplateContext.class.getName() + " interface that does " + "not provide local-variable support. In order to have local-variable support, the variables map " + "implementation should also implement the " + IEngineContext.class.getName() + " interface");
            }
            // NOTE this IEngineContext interface is internal and should not be used in users' code
            ((IEngineContext) context).setVariables(fragmentParameters);
        }
        // Once parameters are in order, just process the template in a nested template engine execution
        final Writer stringWriter = new FastStringWriter(200);
        configuration.getTemplateManager().process(fragmentModel, context, stringWriter);
        // We will insert the result as NON-PROCESSABLE text (it's already been processed!)
        if (this.replaceHost) {
            structureHandler.replaceWith(stringWriter.toString(), false);
        } else {
            structureHandler.setBody(stringWriter.toString(), false);
        }
        return;
    }
    /*
         * APPLY THE FRAGMENT'S TEMPLATE RESOLUTION so that all code inside the fragment is executed with its own
         * template resolution info (working as if it were a local variable)
         */
    final TemplateData fragmentTemplateData = fragmentModel.getTemplateData();
    structureHandler.setTemplateData(fragmentTemplateData);
    /*
         * APPLY THE FRAGMENT PARAMETERS AS LOCAL VARIABLES, perhaps after reshaping it according to the fragment signature
         */
    if (fragmentParameters != null && fragmentParameters.size() > 0) {
        for (final Map.Entry<String, Object> fragmentParameterEntry : fragmentParameters.entrySet()) {
            structureHandler.setLocalVariable(fragmentParameterEntry.getKey(), fragmentParameterEntry.getValue());
        }
    }
    /*
         * IF WE ARE ASKING ONLY FOR CONTENTS (th:include), THEN REMOVE THE CONTAINER BLOCK
         */
    if (this.insertOnlyContents && fragmentTemplateData.hasTemplateSelectors()) {
        /*
             * In the case of th:include, things get a bit complicated because we need to remove the "element envelopes"
             * that contain what we really want to include (these envelopes' contents). So we will need to traverse
             * the entire returned model detecting those envelopes (open+close tags at model level == 0) and remove
             * them, along with anything else that is also at that level 0.
             */
        final IModel model = fragmentModel.cloneModel();
        int modelLevel = 0;
        int n = model.size();
        while (n-- != 0) {
            // We traverse backwards so that we can modify at the same time
            final ITemplateEvent event = model.get(n);
            if (event instanceof ICloseElementTag) {
                if (((ICloseElementTag) event).isUnmatched()) {
                    // This is an unmatched close tag (no corresponding open), therefore should not affect our count
                    continue;
                }
                if (modelLevel <= 0) {
                    model.remove(n);
                }
                modelLevel++;
                continue;
            }
            if (event instanceof IOpenElementTag) {
                modelLevel--;
                if (modelLevel <= 0) {
                    model.remove(n);
                }
                continue;
            }
            if (modelLevel <= 0) {
                model.remove(n);
            }
        }
        if (this.replaceHost) {
            structureHandler.replaceWith(model, true);
        } else {
            structureHandler.setBody(model, true);
        }
        return;
    }
    if (this.replaceHost) {
        structureHandler.replaceWith(fragmentModel, true);
    } else {
        structureHandler.setBody(fragmentModel, true);
    }
}