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
 56pub fn parse_data_form(root: &Element) -> Result<DataForm, Error> {
 57    if !root.is("x", ns::DATA_FORMS) {
 58        return Err(Error::ParseError("This is not a data form element."));
 59    }
 60
 61    let type_: DataFormType = match root.attr("type") {
 62        Some(type_) => type_.parse()?,
 63        None => return Err(Error::ParseError("Type attribute on data form is mandatory.")),
 64    };
 65    let mut fields = vec!();
 66    let mut form_type = None;
 67    for field in root.children() {
 68        if field.is("field", ns::DATA_FORMS) {
 69            let var = field.attr("var").ok_or(Error::ParseError("Field must have a 'var' attribute."))?;
 70            let field_type = field.attr("type").unwrap_or("text-single");
 71            let label = field.attr("label").and_then(|label| label.parse().ok());
 72            let mut values = vec!();
 73            let mut media = vec!();
 74            for element in field.children() {
 75                if element.is("value", ns::DATA_FORMS) {
 76                    values.push(element.text());
 77                } else if element.is("media", ns::MEDIA_ELEMENT) {
 78                    match MediaElement::try_from(element) {
 79                        Ok(media_element) => media.push(media_element),
 80                        Err(_) => (), // TODO: is it really nice to swallow this error?
 81                    }
 82                } else {
 83                    return Err(Error::ParseError("Field child isn’t a value or media element."));
 84                }
 85            }
 86            if var == "FORM_TYPE" && field_type == "hidden" {
 87                if form_type != None {
 88                    return Err(Error::ParseError("More than one FORM_TYPE in a data form."));
 89                }
 90                if values.len() != 1 {
 91                    return Err(Error::ParseError("Wrong number of values in FORM_TYPE."));
 92                }
 93                form_type = Some(values[0].clone());
 94            }
 95            fields.push(Field {
 96                var: var.to_owned(),
 97                type_: field_type.to_owned(),
 98                label: label,
 99                values: values,
100                media: media,
101            });
102        } else {
103            return Err(Error::ParseError("Unknown field type in data form."));
104        }
105    }
106    Ok(DataForm { type_: type_, form_type: form_type, fields: fields })
107}
108
109#[cfg(test)]
110mod tests {
111    use minidom::Element;
112    use error::Error;
113    use data_forms;
114
115    #[test]
116    fn test_simple() {
117        let elem: Element = "<x xmlns='jabber:x:data' type='result'/>".parse().unwrap();
118        let form = data_forms::parse_data_form(&elem).unwrap();
119        assert_eq!(form.type_, data_forms::DataFormType::Result_);
120        assert!(form.form_type.is_none());
121        assert!(form.fields.is_empty());
122    }
123
124    #[test]
125    fn test_invalid() {
126        let elem: Element = "<x xmlns='jabber:x:data'/>".parse().unwrap();
127        let error = data_forms::parse_data_form(&elem).unwrap_err();
128        let message = match error {
129            Error::ParseError(string) => string,
130            _ => panic!(),
131        };
132        assert_eq!(message, "Type attribute on data form is mandatory.");
133
134        let elem: Element = "<x xmlns='jabber:x:data' type='coucou'/>".parse().unwrap();
135        let error = data_forms::parse_data_form(&elem).unwrap_err();
136        let message = match error {
137            Error::ParseError(string) => string,
138            _ => panic!(),
139        };
140        assert_eq!(message, "Unknown data form type.");
141    }
142
143    #[test]
144    fn test_wrong_child() {
145        let elem: Element = "<x xmlns='jabber:x:data' type='cancel'><coucou/></x>".parse().unwrap();
146        let error = data_forms::parse_data_form(&elem).unwrap_err();
147        let message = match error {
148            Error::ParseError(string) => string,
149            _ => panic!(),
150        };
151        assert_eq!(message, "Unknown field type in data form.");
152    }
153}