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;
 11
 12use error::Error;
 13use ns;
 14
 15use media_element::MediaElement;
 16
 17#[derive(Debug, Clone)]
 18pub struct Field {
 19    pub var: String,
 20    pub type_: String, // TODO: use an enum here.
 21    pub label: Option<String>,
 22    pub values: Vec<String>,
 23    pub media: Vec<MediaElement>,
 24}
 25
 26#[derive(Debug, Clone, PartialEq)]
 27pub enum DataFormType {
 28    Cancel,
 29    Form,
 30    Result_,
 31    Submit,
 32}
 33
 34impl FromStr for DataFormType {
 35    type Err = Error;
 36
 37    fn from_str(s: &str) -> Result<DataFormType, Error> {
 38        Ok(match s {
 39            "cancel" => DataFormType::Cancel,
 40            "form" => DataFormType::Form,
 41            "result" => DataFormType::Result_,
 42            "submit" => DataFormType::Submit,
 43
 44            _ => return Err(Error::ParseError("Unknown data form type.")),
 45        })
 46    }
 47}
 48
 49#[derive(Debug, Clone)]
 50pub struct DataForm {
 51    pub type_: DataFormType,
 52    pub form_type: Option<String>,
 53    pub fields: Vec<Field>,
 54}
 55
 56impl<'a> TryFrom<&'a Element> for DataForm {
 57    type Error = Error;
 58
 59    fn try_from(elem: &'a Element) -> Result<DataForm, Error> {
 60        if !elem.is("x", ns::DATA_FORMS) {
 61            return Err(Error::ParseError("This is not a data form element."));
 62        }
 63
 64        let type_: DataFormType = match elem.attr("type") {
 65            Some(type_) => type_.parse()?,
 66            None => return Err(Error::ParseError("Type attribute on data form is mandatory.")),
 67        };
 68        let mut fields = vec!();
 69        let mut form_type = None;
 70        for field in elem.children() {
 71            if field.is("field", ns::DATA_FORMS) {
 72                let var = field.attr("var").ok_or(Error::ParseError("Field must have a 'var' attribute."))?;
 73                let field_type = field.attr("type").unwrap_or("text-single");
 74                let label = field.attr("label").and_then(|label| label.parse().ok());
 75                let mut values = vec!();
 76                let mut media = vec!();
 77                for element in field.children() {
 78                    if element.is("value", ns::DATA_FORMS) {
 79                        values.push(element.text());
 80                    } else if element.is("media", ns::MEDIA_ELEMENT) {
 81                        match MediaElement::try_from(element) {
 82                            Ok(media_element) => media.push(media_element),
 83                            Err(_) => (), // TODO: is it really nice to swallow this error?
 84                        }
 85                    } else {
 86                        return Err(Error::ParseError("Field child isn’t a value or media element."));
 87                    }
 88                }
 89                if var == "FORM_TYPE" && field_type == "hidden" {
 90                    if form_type != None {
 91                        return Err(Error::ParseError("More than one FORM_TYPE in a data form."));
 92                    }
 93                    if values.len() != 1 {
 94                        return Err(Error::ParseError("Wrong number of values in FORM_TYPE."));
 95                    }
 96                    form_type = Some(values[0].clone());
 97                }
 98                fields.push(Field {
 99                    var: var.to_owned(),
100                    type_: field_type.to_owned(),
101                    label: label,
102                    values: values,
103                    media: media,
104                });
105            } else {
106                return Err(Error::ParseError("Unknown field type in data form."));
107            }
108        }
109        Ok(DataForm { type_: type_, form_type: form_type, fields: fields })
110    }
111}
112
113#[cfg(test)]
114mod tests {
115    use super::*;
116
117    #[test]
118    fn test_simple() {
119        let elem: Element = "<x xmlns='jabber:x:data' type='result'/>".parse().unwrap();
120        let form = DataForm::try_from(&elem).unwrap();
121        assert_eq!(form.type_, DataFormType::Result_);
122        assert!(form.form_type.is_none());
123        assert!(form.fields.is_empty());
124    }
125
126    #[test]
127    fn test_invalid() {
128        let elem: Element = "<x xmlns='jabber:x:data'/>".parse().unwrap();
129        let error = DataForm::try_from(&elem).unwrap_err();
130        let message = match error {
131            Error::ParseError(string) => string,
132            _ => panic!(),
133        };
134        assert_eq!(message, "Type attribute on data form is mandatory.");
135
136        let elem: Element = "<x xmlns='jabber:x:data' type='coucou'/>".parse().unwrap();
137        let error = DataForm::try_from(&elem).unwrap_err();
138        let message = match error {
139            Error::ParseError(string) => string,
140            _ => panic!(),
141        };
142        assert_eq!(message, "Unknown data form type.");
143    }
144
145    #[test]
146    fn test_wrong_child() {
147        let elem: Element = "<x xmlns='jabber:x:data' type='cancel'><coucou/></x>".parse().unwrap();
148        let error = DataForm::try_from(&elem).unwrap_err();
149        let message = match error {
150            Error::ParseError(string) => string,
151            _ => panic!(),
152        };
153        assert_eq!(message, "Unknown field type in data form.");
154    }
155}