validationtaglib.groovy

grails用户使用指南

/* Copyright 2004-2005 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT c;pWARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import org.springframework.validation.Errors;
import org.springframework.context.NoSuchMessageException;
import org.springframework.web.servlet.support.RequestContextUtils as RCU;
import org.codehaus.groovy.grails.commons.GrailsClassUtils as GCU;

/**
*  A  tag lib that provides tags to handle validation and errors
*
* @author Graeme Rocher
* @since 17-Jan-2006
*/

class ValidationTagLib {
    /**
     * Checks if the request has errors either for a field or global errors
     */
    def hasErrors = { attrs, body ->
        def model = attrs['model']
        def checkList = []
        if(model) {
            checkList = model.findAll { k,v ->
                grailsApplication.isGrailsDomainClass(v.class)
            }
        }
        if(attrs['bean']) {
            checkList << attrs['bean']
        }
        else {
			if(request.attributeNames) {
				request.attributeNames.each { ra ->
					if(ra) {
                        if(ra instanceof Errors)
                            checkList << ra
                        else if(grailsApplication.isGrailsDomainClass(ra.class))
                            checkList << ra
					}
				}
			}
        }

        for(i in checkList) {
            def errors = null
            if(grailsApplication.isGrailsDomainClass(i.class)) {
                if(i.hasErrors())
                    errors = i.errors
            }
            else if(i instanceof Errors) {
               errors = i
            }
            if(errors) {
                if(attrs['field']) {
                    if(errors.hasFieldErrors(attrs['field'])) {
                        body()
                    }
                }
                else {
                    body()
                }
            }
        }
    }

    /**
     * Loops through each error for either field or global errors
     */
    def eachError = { attrs, body ->
        def model = attrs['model']
        def errorList = []
        if(model) {
            errorList = model.findAll { k,v ->
                grailsApplication.isGrailsDomainClass(v.class)
            }
        }
        if(attrs['bean']) {
            errorList << attrs['bean']
        }
        else {
            request.attributeNames.each {
                def ra = request[it]
                if(ra) {
                    if(ra instanceof Errors)
                        errorList << ra
                    else if(grailsApplication.isGrailsDomainClass(ra.class))
                        errorList << ra
                }
            }
        }

        for(i in errorList) {
            def errors = null
            if(grailsApplication.isGrailsDomainClass(i.class)) {
                if(i.hasErrors())
                    errors = i.errors
            }
            else if(i instanceof Errors) {
               errors = i
            }
            if(errors && errors.hasErrors()) {
                if(attrs['field']) {
                    if(errors.hasFieldErrors(attrs['field'])) {
                        errors.getFieldErrors( attrs["field"] ).each {
                            body(it)
                        }
                    }
                }
                else {
                    errors.allErrors.each {
                        body( it )
                    }
                }
            }
        }
    }

    /**
     * Loops through each error and renders it using one of the supported mechanisms (defaults to "list" if unsupported)
     */
    def renderErrors = { attrs, body ->
        def renderAs = attrs.remove('as')
        if(!renderAs) renderAs = 'list'

        if(renderAs == 'list') {
            out << "<ul>"
            eachError(attrs, {
                out << "<li>"
                message(error:it)
                out << "</li>"
              }
            )
            out << "</ul>"
        }
    }
    /**
     * Resolves a message code for a given error or code from the resource bundle
     */
    def message = { attrs ->
          def messageSource = grailsAttributes
                                .getApplicationContext()
                                .getBean("messageSource")

          def locale = RCU.getLocale(request)

          if(attrs['error']) {
                def error = attrs['error']
                def defaultMessage = ( attrs['default'] ? attrs['default'] : error.defaultMessage )
                def message = messageSource.getMessage( error.code,
                                                        error.arguments,
                                                        defaultMessage,
                                                        locale )
                if(message) {
                    out << message
                }
                else {
                    out << error.code
                }
          }
          if(attrs['code']) {
                def code = attrs['code']
                def args = attrs['args'] 
                def defaultMessage = ( attrs['default'] ? attrs['default'] : code )

                def message = messageSource.getMessage( code,
                                                        args == null ? null : args.toArray(),
                                                        defaultMessage,
                                                        locale )
                if(message) {
                    out << message
                }
                else {
                    out << code
                }
          }
    }
    // Maps out how Grails contraints map to Apache commons validators
    static CONSTRAINT_TYPE_MAP = [ email : 'email',
                                             creditCard : 'creditCard',
                                             match : 'mask',
                                             blank: 'required',
                                             nullable: 'required',
                                             maxSize: 'maxLength',
                                             minSize: 'minLength',
                                             range: 'intRange',
                                             size: 'intRange',
                                             length: 'maxLength,minLength' ]
    /**
     * Validates a form using Apache commons validator javascript against constraints defined in a Grails
     * domain class
     *
     * TODO: This tag is a work in progress
     */
    def validate = { attrs, body ->
        def form = attrs["form"]
        def againstClass = attrs["against"]
        if(!form)
            throwTagError("Tag [validate] is missing required attribute [form]")

        if(!againstClass) {
            againstClass = form.substring(0,1).toUpperCase() + form.substring(1)
        }

        def app = grailsAttributes.getGrailsApplication()
        def dc = app.getGrailsDomainClass(againstClass)

        if(!dc)
            throwTagError("Tag [validate] could not find a domain class to validate against for name [${againstClass}]")

        def constrainedProperties = dc.constrainedProperties.collect { k,v -> return v }
        def appliedConstraints = []

        constrainedProperties.each {
           appliedConstraints += it.collect{ it.appliedConstraints }
        }

        appliedConstraints = appliedConstraints.flatten()
        def fieldValidations = [:]
        appliedConstraints.each {
            def validateType = CONSTRAINT_TYPE_MAP[it.name]
            if(validateType) {
                if(fieldValidations[validateType]) {
                    fieldValidations[validateType] << it
                }
                else {
                     fieldValidations[validateType] =  [it]
                }
            }
        }

        out << '<script type="text/javascript">\n'
        fieldValidations.each { k,v ->
           def validateType = k

           if(validateType) {

                def validateTypes = [validateType]

                if(validateType.contains(",")) {
                    validateTypes = validateType.split(",")
                }


                validateTypes.each { vt ->
                    // import required script
                    def scriptName = "org/apache/commons/validator/javascript/validate" + vt.substring(0,1).toUpperCase() + vt.substring(1) + ".js"
                    def inStream = getClass().classLoader.getResourceAsStream(scriptName)
                    if(inStream) {
                        out << inStream.text
                    }

                    out << "function ${form}_${vt}() {"
                    v.each { constraint ->
                           out << "this.${constraint.propertyName} = new Array("
                           out << "document.forms['${form}'].elements['${constraint.propertyName}']," // the field
                           out << '"Test message"' // TODO: Resolve the actual message
                           switch(vt) {
                                case 'mask': out << ",function() { return '${constraint.regex}'; }";break;
                                case 'intRange': out << ",function() { if(arguments[0]=='min') return ${constraint.range.from}; else return ${constraint.range.to} }";break;
                                case 'floatRange': out << ",function() { if(arguments[0]=='min') return ${constraint.range.from}; else return ${constraint.range.to} }";break;
                                case 'maxLength': out << ",function() { return ${constraint.maxSize};  }";break;
                                case 'minLength': out << ",function() { return ${constraint.minSize};  }";break;
                           }
                           out << ');\n'
                    }
                    out << "}\n"
                }
            }
        }
        out << 'function validateForm(form) {\n'
         fieldValidations.each { k,v ->
               def validateType = k.substring(0,1).toUpperCase() + k.substring(1)
               out << "if(!validate${validateType}(form)) return false;\n"
         }
        out << 'return true;\n';
        out << '}\n'
      //  out << "document.forms['${attrs['form']}'].onsubmit = function(e) {return validateForm(this)}\n"
        out << '</script>'
    }
}