data_forms.rs

  1// Copyright (c) 2017 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
  2//
  3// This Source Code Form is subject to the terms of the Mozilla Public
  4// License, v. 2.0. If a copy of the MPL was not distributed with this
  5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
  6
  7use try_from::TryFrom;
  8use std::str::FromStr;
  9
 10use minidom::{Element, IntoAttributeValue};
 11
 12use error::Error;
 13use ns;
 14
 15use media_element::MediaElement;
 16
 17generate_attribute!(FieldType, "type", {
 18    Boolean => "boolean",
 19    Fixed => "fixed",
 20    Hidden => "hidden",
 21    JidMulti => "jid-multi",
 22    JidSingle => "jid-single",
 23    ListMulti => "list-multi",
 24    ListSingle => "list-single",
 25    TextMulti => "text-multi",
 26    TextPrivate => "text-private",
 27    TextSingle => "text-single",
 28}, Default = TextSingle);
 29
 30#[derive(Debug, Clone)]
 31pub struct Option_ {
 32    pub label: Option<String>,
 33    pub value: String,
 34}
 35
 36impl From<Option_> for Element {
 37    fn from(option: Option_) -> Element {
 38        Element::builder("option")
 39                .ns(ns::DATA_FORMS)
 40                .attr("label", option.label)
 41                .append(Element::builder("value")
 42                                .ns(ns::DATA_FORMS)
 43                                .append(option.value)
 44                                .build())
 45                .build()
 46    }
 47}
 48
 49#[derive(Debug, Clone)]
 50pub struct Field {
 51    pub var: String,
 52    pub type_: FieldType,
 53    pub label: Option<String>,
 54    pub required: bool,
 55    pub options: Vec<Option_>,
 56    pub values: Vec<String>,
 57    pub media: Vec<MediaElement>,
 58}
 59
 60impl From<Field> for Element {
 61    fn from(field: Field) -> Element {
 62        Element::builder("field")
 63                .ns(ns::DATA_FORMS)
 64                .attr("var", field.var)
 65                .attr("type", field.type_)
 66                .attr("label", field.label)
 67                .append(if field.required { Some(Element::builder("required").ns(ns::DATA_FORMS).build()) } else { None })
 68                .append(field.options)
 69                .append(field.values.into_iter().map(|value| {
 70                     Element::builder("value").ns(ns::DATA_FORMS).append(value).build()
 71                 }).collect::<Vec<_>>())
 72                .append(field.media)
 73                .build()
 74    }
 75}
 76
 77generate_attribute!(DataFormType, "type", {
 78    Cancel => "cancel",
 79    Form => "form",
 80    Result_ => "result",
 81    Submit => "submit",
 82});
 83
 84#[derive(Debug, Clone)]
 85pub struct DataForm {
 86    pub type_: DataFormType,
 87    pub form_type: Option<String>,
 88    pub title: Option<String>,
 89    pub instructions: Option<String>,
 90    pub fields: Vec<Field>,
 91}
 92
 93impl TryFrom<Element> for DataForm {
 94    type Err = Error;
 95
 96    fn try_from(elem: Element) -> Result<DataForm, Error> {
 97        if !elem.is("x", ns::DATA_FORMS) {
 98            return Err(Error::ParseError("This is not a data form element."));
 99        }
100        let type_ = get_attr!(elem, "type", required);
101        let mut form = DataForm {
102            type_: type_,
103            form_type: None,
104            title: None,
105            instructions: None,
106            fields: vec!(),
107        };
108        for child in elem.children() {
109            if child.is("title", ns::DATA_FORMS) {
110                if form.title.is_some() {
111                    return Err(Error::ParseError("More than one title in form element."));
112                }
113                for _ in child.children() {
114                    return Err(Error::ParseError("Title element must not have any child."));
115                }
116                for _ in child.attrs() {
117                    return Err(Error::ParseError("Title element must not have any attribute."));
118                }
119                form.title = Some(child.text());
120            } else if child.is("instructions", ns::DATA_FORMS) {
121                if form.instructions.is_some() {
122                    return Err(Error::ParseError("More than one instructions in form element."));
123                }
124                for _ in child.children() {
125                    return Err(Error::ParseError("instructions element must not have any child."));
126                }
127                for _ in child.attrs() {
128                    return Err(Error::ParseError("instructions element must not have any attribute."));
129                }
130                form.instructions = Some(child.text());
131            } else if child.is("field", ns::DATA_FORMS) {
132                let var: String = get_attr!(child, "var", required);
133                let field_type = get_attr!(child, "type", default);
134                let label = get_attr!(child, "label", optional);
135
136                let is_form_type = var == "FORM_TYPE" && field_type == FieldType::Hidden;
137                let is_list = field_type == FieldType::ListSingle || field_type == FieldType::ListMulti;
138                let mut field = Field {
139                    var: var,
140                    type_: field_type,
141                    label: label,
142                    required: false,
143                    options: vec!(),
144                    values: vec!(),
145                    media: vec!(),
146                };
147                for element in child.children() {
148                    if element.is("value", ns::DATA_FORMS) {
149                        for _ in element.children() {
150                            return Err(Error::ParseError("Value element must not have any child."));
151                        }
152                        for _ in element.attrs() {
153                            return Err(Error::ParseError("Value element must not have any attribute."));
154                        }
155                        field.values.push(element.text());
156                    } else if element.is("required", ns::DATA_FORMS) {
157                        if field.required {
158                            return Err(Error::ParseError("More than one required element."));
159                        }
160                        for _ in element.children() {
161                            return Err(Error::ParseError("Required element must not have any child."));
162                        }
163                        for _ in element.attrs() {
164                            return Err(Error::ParseError("Required element must not have any attribute."));
165                        }
166                        field.required = true;
167                    } else if element.is("option", ns::DATA_FORMS) {
168                        if !is_list {
169                            return Err(Error::ParseError("Option element found in non-list field."));
170                        }
171                        let label = get_attr!(element, "label", optional);
172                        let mut value = None;
173                        for child2 in element.children() {
174                            if child2.is("value", ns::DATA_FORMS) {
175                                if value.is_some() {
176                                    return Err(Error::ParseError("More than one value element in option element"));
177                                }
178                                value = Some(child2.text());
179                            } else {
180                                return Err(Error::ParseError("Non-value element in option element"));
181                            }
182                        }
183                        let value = value.ok_or(Error::ParseError("No value element in option element"))?;
184                        field.options.push(Option_ {
185                            label: label,
186                            value: value,
187                        });
188                    } else if element.is("media", ns::MEDIA_ELEMENT) {
189                        match MediaElement::try_from(element.clone()) {
190                            Ok(media_element) => field.media.push(media_element),
191                            Err(_) => (), // TODO: is it really nice to swallow this error?
192                        }
193                    } else {
194                        return Err(Error::ParseError("Field child isn’t a value or media element."));
195                    }
196                }
197                if is_form_type {
198                    if form.form_type.is_some() {
199                        return Err(Error::ParseError("More than one FORM_TYPE in a data form."));
200                    }
201                    if field.values.len() != 1 {
202                        return Err(Error::ParseError("Wrong number of values in FORM_TYPE."));
203                    }
204                    form.form_type = Some(field.values[0].clone());
205                }
206                form.fields.push(field);
207            } else {
208                return Err(Error::ParseError("Unknown child in data form element."));
209            }
210        }
211        Ok(form)
212    }
213}
214
215impl From<DataForm> for Element {
216    fn from(form: DataForm) -> Element {
217        Element::builder("x")
218                .ns(ns::DATA_FORMS)
219                .attr("type", form.type_)
220                .append(if form.title.is_some() { Some(Element::builder("title").ns(ns::DATA_FORMS).append(form.title)) } else { None })
221                .append(if form.instructions.is_some() { Some(Element::builder("instructions").ns(ns::DATA_FORMS).append(form.instructions)) } else { None })
222                .append(form.fields)
223                .build()
224    }
225}
226
227#[cfg(test)]
228mod tests {
229    use super::*;
230
231    #[test]
232    fn test_simple() {
233        let elem: Element = "<x xmlns='jabber:x:data' type='result'/>".parse().unwrap();
234        let form = DataForm::try_from(elem).unwrap();
235        assert_eq!(form.type_, DataFormType::Result_);
236        assert!(form.form_type.is_none());
237        assert!(form.fields.is_empty());
238    }
239
240    #[test]
241    fn test_invalid() {
242        let elem: Element = "<x xmlns='jabber:x:data'/>".parse().unwrap();
243        let error = DataForm::try_from(elem).unwrap_err();
244        let message = match error {
245            Error::ParseError(string) => string,
246            _ => panic!(),
247        };
248        assert_eq!(message, "Required attribute 'type' missing.");
249
250        let elem: Element = "<x xmlns='jabber:x:data' type='coucou'/>".parse().unwrap();
251        let error = DataForm::try_from(elem).unwrap_err();
252        let message = match error {
253            Error::ParseError(string) => string,
254            _ => panic!(),
255        };
256        assert_eq!(message, "Unknown value for 'type' attribute.");
257    }
258
259    #[test]
260    fn test_wrong_child() {
261        let elem: Element = "<x xmlns='jabber:x:data' type='cancel'><coucou/></x>".parse().unwrap();
262        let error = DataForm::try_from(elem).unwrap_err();
263        let message = match error {
264            Error::ParseError(string) => string,
265            _ => panic!(),
266        };
267        assert_eq!(message, "Unknown child in data form element.");
268    }
269}