Add FreeMarker macro support in spring-webflux

spring-webflux/src/main/java/org/springframework/web/reactive/result/view/freemarker/FreeMarkerConfigurer.java

@@ -46,8 +46,6 @@
  * instance via the "configuration" property. This allows to share a FreeMarker
  * Configuration for web and email usage for example.
  *
- * <p>TODO: macros
- *
  * <p>This configurer registers a template loader for this package, allowing to
  * reference the "spring.ftl" macro library contained in this package:
  *

spring-webflux/src/main/resources/org/springframework/web/reactive/result/view/freemarker/spring.ftl

@@ -0,0 +1,355 @@
+<#ftl output_format="HTML" strip_whitespace=true>
+<#--
+ * spring.ftl
+ *
+ * This file consists of a collection of FreeMarker macros aimed at easing
+ * some of the common requirements of web applications - in particular
+ * handling of forms.
+ *
+ * Spring's FreeMarker support will automatically make this file and therefore
+ * all macros within it available to any application using Spring's
+ * FreeMarkerConfigurer.
+ *
+ * To take advantage of these macros, the "exposeSpringMacroHelpers" property
+ * of the FreeMarker class needs to be set to "true". This will expose a
+ * RequestContext under the name "springMacroRequestContext", as needed by
+ * the macros in this library.
+ *
+ * @author Darren Davison
+ * @author Juergen Hoeller
+ * @author Issam El-atif
+ * @since 5.2
+ -->
+
+<#--
+ * message
+ *
+ * Macro to translate a message code into a message.
+ -->
+<#macro message code>${springMacroRequestContext.getMessage(code)?no_esc}</#macro>
+
+<#--
+ * messageText
+ *
+ * Macro to translate a message code into a message,
+ * using the given default text if no message found.
+ -->
+<#macro messageText code, text>${springMacroRequestContext.getMessage(code, text)?no_esc}</#macro>
+
+<#--
+ * messageArgs
+ *
+ * Macro to translate a message code with arguments into a message.
+ -->
+<#macro messageArgs code, args>${springMacroRequestContext.getMessage(code, args)?no_esc}</#macro>
+
+<#--
+ * messageArgsText
+ *
+ * Macro to translate a message code with arguments into a message,
+ * using the given default text if no message found.
+ -->
+<#macro messageArgsText code, args, text>${springMacroRequestContext.getMessage(code, args, text)?no_esc}</#macro>
+
+<#--
+ * url
+ *
+ * Takes a relative URL and makes it absolute from the server root by
+ * adding the context root for the web application.
+ -->
+<#macro url relativeUrl extra...><#if extra?? && extra?size!=0>${springMacroRequestContext.getContextUrl(relativeUrl,extra)?no_esc}<#else>${springMacroRequestContext.getContextUrl(relativeUrl)?no_esc}</#if></#macro>
+
+<#--
+ * bind
+ *
+ * Exposes a BindStatus object for the given bind path, which can be
+ * a bean (e.g. "person") to get global errors, or a bean property
+ * (e.g. "person.name") to get field errors. Can be called multiple times
+ * within a form to bind to multiple command objects and/or field names.
+ *
+ * This macro will participate in the default HTML escape setting for the given
+ * RequestContext. This can be customized by calling "setDefaultHtmlEscape"
+ * on the "springMacroRequestContext" context variable, or via the
+ * "defaultHtmlEscape" context-param in web.xml (same as for the JSP bind tag).
+ * Also regards a "htmlEscape" variable in the namespace of this library.
+ *
+ * Producing no output, the following context variable will be available
+ * each time this macro is referenced (assuming you import this library in
+ * your templates with the namespace 'spring'):
+ *
+ *   spring.status : a BindStatus instance holding the command object name,
+ *   expression, value, and error messages and codes for the path supplied
+ *
+ * @param path the path (string value) of the value required to bind to.
+ *     Spring defaults to a command name of "command" but this can be
+ *     overridden by user configuration.
+ -->
+<#macro bind path>
+    <#if htmlEscape?exists>
+        <#assign status = springMacroRequestContext.getBindStatus(path, htmlEscape)>
+    <#else>
+        <#assign status = springMacroRequestContext.getBindStatus(path)>
+    </#if>
+    <#-- assign a temporary value, forcing a string representation for any
+    kind of variable. This temp value is only used in this macro lib -->
+    <#if status.value?exists && status.value?is_boolean>
+        <#assign stringStatusValue=status.value?string>
+    <#else>
+        <#assign stringStatusValue=status.value?default("")>
+    </#if>
+</#macro>
+
+<#--
+ * bindEscaped
+ *
+ * Similar to spring:bind, but takes an explicit HTML escape flag rather
+ * than relying on the default HTML escape setting.
+ -->
+<#macro bindEscaped path, htmlEscape>
+    <#assign status = springMacroRequestContext.getBindStatus(path, htmlEscape)>
+    <#-- assign a temporary value, forcing a string representation for any
+    kind of variable. This temp value is only used in this macro lib -->
+    <#if status.value?exists && status.value?is_boolean>
+        <#assign stringStatusValue=status.value?string>
+    <#else>
+        <#assign stringStatusValue=status.value?default("")>
+    </#if>
+</#macro>
+
+<#--
+ * formInput
+ *
+ * Display a form input field of type 'text' and bind it to an attribute
+ * of a command or bean.
+ *
+ * @param path the name of the field to bind to
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+ -->
+<#macro formInput path attributes="" fieldType="text">
+    <@bind path/>
+    <input type="${fieldType}" id="${status.expression?replace('[','')?replace(']','')}" name="${status.expression}" value="<#if fieldType!="password">${stringStatusValue}</#if>" ${attributes?no_esc}<@closeTag/>
+</#macro>
+
+<#--
+ * formPasswordInput
+ *
+ * Display a form input field of type 'password' and bind it to an attribute
+ * of a command or bean. No value will ever be displayed. This functionality
+ * can also be obtained by calling the formInput macro with a 'type' parameter
+ * of 'password'.
+ *
+ * @param path the name of the field to bind to
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+ -->
+<#macro formPasswordInput path attributes="">
+    <@formInput path, attributes, "password"/>
+</#macro>
+
+<#--
+ * formHiddenInput
+ *
+ * Generate a form input field of type 'hidden' and bind it to an attribute
+ * of a command or bean. This functionality can also be obtained by calling
+ * the formInput macro with a 'type' parameter of 'hidden'.
+ *
+ * @param path the name of the field to bind to
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+ -->
+<#macro formHiddenInput path attributes="">
+    <@formInput path, attributes, "hidden"/>
+</#macro>
+
+<#--
+ * formTextarea
+ *
+ * Display a text area and bind it to an attribute of a command or bean.
+ *
+ * @param path the name of the field to bind to
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+ -->
+<#macro formTextarea path attributes="">
+    <@bind path/>
+    <textarea id="${status.expression?replace('[','')?replace(']','')}" name="${status.expression}" ${attributes?no_esc}>
+${stringStatusValue}</textarea>
+</#macro>
+
+<#--
+ * formSingleSelect
+ *
+ * Show a selectbox (dropdown) input element allowing a single value to be chosen
+ * from a list of options.
+ *
+ * @param path the name of the field to bind to
+ * @param options a map (value=label) of all the available options
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+-->
+<#macro formSingleSelect path options attributes="">
+    <@bind path/>
+    <select id="${status.expression?replace('[','')?replace(']','')}" name="${status.expression}" ${attributes?no_esc}>
+        <#if options?is_hash>
+            <#list options?keys as value>
+            <option value="${value}"<@checkSelected value/>>${options[value]}</option>
+            </#list>
+        <#else> 
+            <#list options as value>
+            <option value="${value}"<@checkSelected value/>>${value}</option>
+            </#list>
+        </#if>
+    </select>
+</#macro>
+
+<#--
+ * formMultiSelect
+ *
+ * Show a listbox of options allowing the user to make 0 or more choices from
+ * the list of options.
+ *
+ * @param path the name of the field to bind to
+ * @param options a map (value=label) of all the available options
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+-->
+<#macro formMultiSelect path options attributes="">
+    <@bind path/>
+    <select multiple="multiple" id="${status.expression?replace('[','')?replace(']','')}" name="${status.expression}" ${attributes?no_esc}>
+        <#list options?keys as value>
+        <#assign isSelected = contains(status.actualValue?default([""]), value)>
+        <option value="${value}"<#if isSelected> selected="selected"</#if>>${options[value]}</option>
+        </#list>
+    </select>
+</#macro>
+
+<#--
+ * formRadioButtons
+ *
+ * Show radio buttons.
+ *
+ * @param path the name of the field to bind to
+ * @param options a map (value=label) of all the available options
+ * @param separator the HTML tag or other character list that should be used to
+ *    separate each option (typically '&nbsp;' or '<br>')
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+-->
+<#macro formRadioButtons path options separator attributes="">
+    <@bind path/>
+    <#list options?keys as value>
+    <#assign id="${status.expression?replace('[','')?replace(']','')}${value_index}">
+    <input type="radio" id="${id}" name="${status.expression}" value="${value}"<#if stringStatusValue == value> checked="checked"</#if> ${attributes?no_esc}<@closeTag/>
+    <label for="${id}">${options[value]}</label>${separator?no_esc}
+    </#list>
+</#macro>
+
+<#--
+ * formCheckboxes
+ *
+ * Show checkboxes.
+ *
+ * @param path the name of the field to bind to
+ * @param options a map (value=label) of all the available options
+ * @param separator the HTML tag or other character list that should be used to
+ *    separate each option (typically '&nbsp;' or '<br>')
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+-->
+<#macro formCheckboxes path options separator attributes="">
+    <@bind path/>
+    <#list options?keys as value>
+    <#assign id="${status.expression?replace('[','')?replace(']','')}${value_index}">
+    <#assign isSelected = contains(status.actualValue?default([""]), value)>
+    <input type="checkbox" id="${id}" name="${status.expression}" value="${value}"<#if isSelected> checked="checked"</#if> ${attributes?no_esc}<@closeTag/>
+    <label for="${id}">${options[value]}</label>${separator?no_esc}
+    </#list>
+    <input type="hidden" name="_${status.expression}" value="on"/>
+</#macro>
+
+<#--
+ * formCheckbox
+ *
+ * Show a single checkbox.
+ *
+ * @param path the name of the field to bind to
+ * @param attributes any additional attributes for the element
+ *    (such as class or CSS styles or size)
+-->
+<#macro formCheckbox path attributes="">
+	<@bind path />
+    <#assign id="${status.expression?replace('[','')?replace(']','')}">
+    <#assign isSelected = status.value?? && status.value?string=="true">
+	<input type="hidden" name="_${status.expression}" value="on"/>
+	<input type="checkbox" id="${id}" name="${status.expression}"<#if isSelected> checked="checked"</#if> ${attributes?no_esc}/>
+</#macro>
+
+<#--
+ * showErrors
+ *
+ * Show validation errors for the currently bound field, with
+ * optional style attributes.
+ *
+ * @param separator the HTML tag or other character list that should be used to
+ *    separate each option (typically '&nbsp;' or '<br>')
+ * @param classOrStyle either the name of a CSS class element (which is defined in
+ *    the template or an external CSS file) or an inline style. If the value passed
+ *    in here contains a colon (:) then a 'style=' attribute will be used,
+ *    otherwise a 'class=' attribute will be used.
+-->
+<#macro showErrors separator classOrStyle="">
+    <#list status.errorMessages as error>
+    <#if classOrStyle == "">
+        <b>${error}</b>
+    <#else>
+        <#if classOrStyle?index_of(":") == -1><#assign attr="class"><#else><#assign attr="style"></#if>
+        <span ${attr}="${classOrStyle}">${error}</span>
+    </#if>
+    <#if error_has_next>${separator?no_esc}</#if>
+    </#list>
+</#macro>
+
+<#--
+ * checkSelected
+ *
+ * Check a value in a list to see if it is the currently selected value.
+ * If so, add the 'selected="selected"' text to the output.
+ * Handles values of numeric and string types.
+ * This function is used internally but can be accessed by user code if required.
+ *
+ * @param value the current value in a list iteration
+-->
+<#macro checkSelected value>
+    <#if stringStatusValue?is_number && stringStatusValue == value?number>selected="selected"</#if>
+    <#if stringStatusValue?is_string && stringStatusValue == value>selected="selected"</#if>
+</#macro>
+
+<#--
+ * contains
+ *
+ * Macro to return true if the list contains the scalar, false if not.
+ * Surprisingly not a FreeMarker builtin.
+ * This function is used internally but can be accessed by user code if required.
+ *
+ * @param list the list to search for the item
+ * @param item the item to search for in the list
+ * @return true if item is found in the list, false otherwise
+-->
+<#function contains list item>
+    <#list list as nextInList>
+    <#if nextInList == item><#return true></#if>
+    </#list>
+    <#return false>
+</#function>
+
+<#--
+ * closeTag
+ *
+ * Simple macro to close an HTML tag that has no body with '>' or '/>',
+ * depending on the value of a 'xhtmlCompliant' variable in the namespace
+ * of this library.
+-->
+<#macro closeTag>
+    <#if xhtmlCompliant?exists && xhtmlCompliant>/><#else>></#if>
+</#macro>