data_forms.rs

  1extern crate minidom;
  2
  3use std::str::FromStr;
  4
  5use minidom::Element;
  6
  7use error::Error;
  8use ns;
  9
 10use media_element::{MediaElement, parse_media_element};
 11
 12#[derive(Debug, Clone)]
 13pub struct Field {
 14    pub var: String,
 15    pub type_: String, // TODO: use an enum here.
 16    pub label: Option<String>,
 17    pub values: Vec<String>,
 18    pub media: Vec<MediaElement>,
 19}
 20
 21#[derive(Debug, Clone, PartialEq)]
 22pub enum DataFormType {
 23    Cancel,
 24    Form,
 25    Result_,
 26    Submit,
 27}
 28
 29impl FromStr for DataFormType {
 30    type Err = Error;
 31
 32    fn from_str(s: &str) -> Result<DataFormType, Error> {
 33        Ok(match s {
 34            "cancel" => DataFormType::Cancel,
 35            "form" => DataFormType::Form,
 36            "result" => DataFormType::Result_,
 37            "submit" => DataFormType::Submit,
 38
 39            _ => return Err(Error::ParseError("Unknown data form type.")),
 40        })
 41    }
 42}
 43
 44#[derive(Debug, Clone)]
 45pub struct DataForm {
 46    pub type_: DataFormType,
 47    pub form_type: Option<String>,
 48    pub fields: Vec<Field>,
 49}
 50
 51pub fn parse_data_form(root: &Element) -> Result<DataForm, Error> {
 52    if !root.is("x", ns::DATA_FORMS) {
 53        return Err(Error::ParseError("This is not a data form element."));
 54    }
 55
 56    let type_: DataFormType = match root.attr("type") {
 57        Some(type_) => type_.parse()?,
 58        None => return Err(Error::ParseError("Type attribute on data form is mandatory.")),
 59    };
 60    let mut fields = vec!();
 61    let mut form_type = None;
 62    for field in root.children() {
 63        if field.is("field", ns::DATA_FORMS) {
 64            let var = field.attr("var").ok_or(Error::ParseError("Field must have a 'var' attribute."))?;
 65            let field_type = field.attr("type").unwrap_or("text-single");
 66            let label = field.attr("label").and_then(|label| label.parse().ok());
 67            let mut values = vec!();
 68            let mut media = vec!();
 69            for element in field.children() {
 70                if element.is("value", ns::DATA_FORMS) {
 71                    values.push(element.text());
 72                } else if element.is("media", ns::MEDIA_ELEMENT) {
 73                    match parse_media_element(element) {
 74                        Ok(media_element) => media.push(media_element),
 75                        Err(_) => (), // TODO: is it really nice to swallow this error?
 76                    }
 77                } else {
 78                    return Err(Error::ParseError("Field child isn’t a value or media element."));
 79                }
 80            }
 81            if var == "FORM_TYPE" && field_type == "hidden" {
 82                if form_type != None {
 83                    return Err(Error::ParseError("More than one FORM_TYPE in a data form."));
 84                }
 85                if values.len() != 1 {
 86                    return Err(Error::ParseError("Wrong number of values in FORM_TYPE."));
 87                }
 88                form_type = Some(values[0].clone());
 89            }
 90            fields.push(Field {
 91                var: var.to_owned(),
 92                type_: field_type.to_owned(),
 93                label: label,
 94                values: values,
 95                media: media,
 96            });
 97        } else {
 98            return Err(Error::ParseError("Unknown field type in data form."));
 99        }
100    }
101    Ok(DataForm { type_: type_, form_type: form_type, fields: fields })
102}
103
104#[cfg(test)]
105mod tests {
106    use minidom::Element;
107    use error::Error;
108    use data_forms;
109
110    #[test]
111    fn test_simple() {
112        let elem: Element = "<x xmlns='jabber:x:data' type='result'/>".parse().unwrap();
113        let form = data_forms::parse_data_form(&elem).unwrap();
114        assert_eq!(form.type_, data_forms::DataFormType::Result_);
115        assert!(form.form_type.is_none());
116        assert!(form.fields.is_empty());
117    }
118
119    #[test]
120    fn test_invalid() {
121        let elem: Element = "<x xmlns='jabber:x:data'/>".parse().unwrap();
122        let error = data_forms::parse_data_form(&elem).unwrap_err();
123        let message = match error {
124            Error::ParseError(string) => string,
125            _ => panic!(),
126        };
127        assert_eq!(message, "Type attribute on data form is mandatory.");
128
129        let elem: Element = "<x xmlns='jabber:x:data' type='coucou'/>".parse().unwrap();
130        let error = data_forms::parse_data_form(&elem).unwrap_err();
131        let message = match error {
132            Error::ParseError(string) => string,
133            _ => panic!(),
134        };
135        assert_eq!(message, "Unknown data form type.");
136    }
137
138    #[test]
139    fn test_wrong_child() {
140        let elem: Element = "<x xmlns='jabber:x:data' type='cancel'><coucou/></x>".parse().unwrap();
141        let error = data_forms::parse_data_form(&elem).unwrap_err();
142        let message = match error {
143            Error::ParseError(string) => string,
144            _ => panic!(),
145        };
146        assert_eq!(message, "Unknown field type in data form.");
147    }
148}