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 std::convert::TryFrom;
  8use std::str::FromStr;
  9
 10use minidom::{Element, IntoElements, IntoAttributeValue, ElementEmitter};
 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});
 29
 30impl Default for FieldType {
 31    fn default() -> FieldType {
 32        FieldType::TextSingle
 33    }
 34}
 35
 36#[derive(Debug, Clone)]
 37pub struct Option_ {
 38    pub label: Option<String>,
 39    pub value: String,
 40}
 41
 42impl From<Option_> for Element {
 43    fn from(option: Option_) -> Element {
 44        Element::builder("option")
 45                .ns(ns::DATA_FORMS)
 46                .attr("label", option.label)
 47                .append(Element::builder("value")
 48                                .ns(ns::DATA_FORMS)
 49                                .append(option.value)
 50                                .build())
 51                .build()
 52    }
 53}
 54
 55impl IntoElements for Option_ {
 56    fn into_elements(self, emitter: &mut ElementEmitter) {
 57        emitter.append_child(self.into());
 58    }
 59}
 60
 61#[derive(Debug, Clone)]
 62pub struct Field {
 63    pub var: String,
 64    pub type_: FieldType,
 65    pub label: Option<String>,
 66    pub required: bool,
 67    pub options: Vec<Option_>,
 68    pub values: Vec<String>,
 69    pub media: Vec<MediaElement>,
 70}
 71
 72impl From<Field> for Element {
 73    fn from(field: Field) -> Element {
 74        Element::builder("field")
 75                .ns(ns::DATA_FORMS)
 76                .attr("var", field.var)
 77                .attr("type", field.type_)
 78                .attr("label", field.label)
 79                .append(if field.required { Some(Element::builder("required").ns(ns::DATA_FORMS).build()) } else { None })
 80                .append(field.options)
 81                .append(field.values.iter().map(|value| {
 82                     Element::builder("value").ns(ns::DATA_FORMS).append(value).build()
 83                 }).collect::<Vec<_>>())
 84                .append(field.media)
 85                .build()
 86    }
 87}
 88
 89impl IntoElements for Field {
 90    fn into_elements(self, emitter: &mut ElementEmitter) {
 91        emitter.append_child(self.into());
 92    }
 93}
 94
 95generate_attribute!(Subscription, "subscription", {
 96    Cancel => "cancel",
 97    Form => "form",
 98    Result_ => "result",
 99    Submit => "submit",
100});
101
102#[derive(Debug, Clone)]
103pub struct DataForm {
104    pub type_: DataFormType,
105    pub form_type: Option<String>,
106    pub title: Option<String>,
107    pub instructions: Option<String>,
108    pub fields: Vec<Field>,
109}
110
111impl TryFrom<Element> for DataForm {
112    type Error = Error;
113
114    fn try_from(elem: Element) -> Result<DataForm, Error> {
115        if !elem.is("x", ns::DATA_FORMS) {
116            return Err(Error::ParseError("This is not a data form element."));
117        }
118        let type_ = get_attr!(elem, "type", required);
119        let mut form = DataForm {
120            type_: type_,
121            form_type: None,
122            title: None,
123            instructions: None,
124            fields: vec!(),
125        };
126        for child in elem.children() {
127            if child.is("title", ns::DATA_FORMS) {
128                if form.title.is_some() {
129                    return Err(Error::ParseError("More than one title in form element."));
130                }
131                for _ in child.children() {
132                    return Err(Error::ParseError("Title element must not have any child."));
133                }
134                for _ in child.attrs() {
135                    return Err(Error::ParseError("Title element must not have any attribute."));
136                }
137                form.title = Some(child.text());
138            } else if child.is("instructions", ns::DATA_FORMS) {
139                if form.instructions.is_some() {
140                    return Err(Error::ParseError("More than one instructions in form element."));
141                }
142                for _ in child.children() {
143                    return Err(Error::ParseError("instructions element must not have any child."));
144                }
145                for _ in child.attrs() {
146                    return Err(Error::ParseError("instructions element must not have any attribute."));
147                }
148                form.instructions = Some(child.text());
149            } else if child.is("field", ns::DATA_FORMS) {
150                let var: String = get_attr!(child, "var", required);
151                let field_type = get_attr!(child, "type", default);
152                let label = get_attr!(child, "label", optional);
153
154                let is_form_type = var == "FORM_TYPE" && field_type == FieldType::Hidden;
155                let is_list = field_type == FieldType::ListSingle || field_type == FieldType::ListMulti;
156                let mut field = Field {
157                    var: var,
158                    type_: field_type,
159                    label: label,
160                    required: false,
161                    options: vec!(),
162                    values: vec!(),
163                    media: vec!(),
164                };
165                for element in child.children() {
166                    if element.is("value", ns::DATA_FORMS) {
167                        for _ in element.children() {
168                            return Err(Error::ParseError("Value element must not have any child."));
169                        }
170                        for _ in element.attrs() {
171                            return Err(Error::ParseError("Value element must not have any attribute."));
172                        }
173                        field.values.push(element.text());
174                    } else if element.is("required", ns::DATA_FORMS) {
175                        if field.required {
176                            return Err(Error::ParseError("More than one required element."));
177                        }
178                        for _ in element.children() {
179                            return Err(Error::ParseError("Required element must not have any child."));
180                        }
181                        for _ in element.attrs() {
182                            return Err(Error::ParseError("Required element must not have any attribute."));
183                        }
184                        field.required = true;
185                    } else if element.is("option", ns::DATA_FORMS) {
186                        if !is_list {
187                            return Err(Error::ParseError("Option element found in non-list field."));
188                        }
189                        let label = get_attr!(element, "label", optional);
190                        let mut value = None;
191                        for child2 in element.children() {
192                            if child2.is("value", ns::DATA_FORMS) {
193                                if value.is_some() {
194                                    return Err(Error::ParseError("More than one value element in option element"));
195                                }
196                                value = Some(child2.text());
197                            } else {
198                                return Err(Error::ParseError("Non-value element in option element"));
199                            }
200                        }
201                        let value = value.ok_or(Error::ParseError("No value element in option element"))?;
202                        field.options.push(Option_ {
203                            label: label,
204                            value: value,
205                        });
206                    } else if element.is("media", ns::MEDIA_ELEMENT) {
207                        match MediaElement::try_from(element.clone()) {
208                            Ok(media_element) => field.media.push(media_element),
209                            Err(_) => (), // TODO: is it really nice to swallow this error?
210                        }
211                    } else {
212                        return Err(Error::ParseError("Field child isn’t a value or media element."));
213                    }
214                }
215                if is_form_type {
216                    if form.form_type.is_some() {
217                        return Err(Error::ParseError("More than one FORM_TYPE in a data form."));
218                    }
219                    if field.values.len() != 1 {
220                        return Err(Error::ParseError("Wrong number of values in FORM_TYPE."));
221                    }
222                    form.form_type = Some(field.values[0].clone());
223                }
224                form.fields.push(field);
225            } else {
226                return Err(Error::ParseError("Unknown child in data form element."));
227            }
228        }
229        Ok(form)
230    }
231}
232
233impl From<DataForm> for Element {
234    fn from(form: DataForm) -> Element {
235        Element::builder("x")
236                .ns(ns::DATA_FORMS)
237                .attr("type", form.type_)
238                .append(form.form_type)
239                .append(form.title)
240                .append(form.instructions)
241                .append(form.fields)
242                .build()
243    }
244}
245
246impl IntoElements for DataForm {
247    fn into_elements(self, emitter: &mut ElementEmitter) {
248        emitter.append_child(self.into());
249    }
250}
251
252#[cfg(test)]
253mod tests {
254    use super::*;
255
256    #[test]
257    fn test_simple() {
258        let elem: Element = "<x xmlns='jabber:x:data' type='result'/>".parse().unwrap();
259        let form = DataForm::try_from(elem).unwrap();
260        assert_eq!(form.type_, DataFormType::Result_);
261        assert!(form.form_type.is_none());
262        assert!(form.fields.is_empty());
263    }
264
265    #[test]
266    fn test_invalid() {
267        let elem: Element = "<x xmlns='jabber:x:data'/>".parse().unwrap();
268        let error = DataForm::try_from(elem).unwrap_err();
269        let message = match error {
270            Error::ParseError(string) => string,
271            _ => panic!(),
272        };
273        assert_eq!(message, "Required attribute 'type' missing.");
274
275        let elem: Element = "<x xmlns='jabber:x:data' type='coucou'/>".parse().unwrap();
276        let error = DataForm::try_from(elem).unwrap_err();
277        let message = match error {
278            Error::ParseError(string) => string,
279            _ => panic!(),
280        };
281        assert_eq!(message, "Unknown data form type.");
282    }
283
284    #[test]
285    fn test_wrong_child() {
286        let elem: Element = "<x xmlns='jabber:x:data' type='cancel'><coucou/></x>".parse().unwrap();
287        let error = DataForm::try_from(elem).unwrap_err();
288        let message = match error {
289            Error::ParseError(string) => string,
290            _ => panic!(),
291        };
292        assert_eq!(message, "Unknown child in data form element.");
293    }
294}