slack_messaging/blocks/
context.rs

1use crate::blocks::elements::Image;
2use crate::composition_objects::TextContent;
3use crate::validators::*;
4
5use serde::Serialize;
6use slack_messaging_derive::Builder;
7
8/// [Context block](https://docs.slack.dev/reference/block-kit/blocks/context-block)
9/// representation.
10///
11/// # Fields and Validations
12///
13/// For more details, see the [official
14/// documentation](https://docs.slack.dev/reference/block-kit/blocks/context-block).
15///
16/// | Field | Type | Required | Validation |
17/// |-------|------|----------|------------|
18/// | elements | Vec<[ContextElement]> | Yes | Max 10 items |
19/// | block_id | String | No | Maximum 255 characters |
20///
21/// # Example
22///
23/// The following is reproduction of [the sample context](https://docs.slack.dev/reference/block-kit/blocks/context-block#examples).
24///
25/// ```
26/// use slack_messaging::mrkdwn;
27/// use slack_messaging::blocks::Context;
28/// use slack_messaging::blocks::elements::Image;
29/// # use std::error::Error;
30///
31/// # fn try_main() -> Result<(), Box<dyn Error>> {
32/// let context = Context::builder()
33///     .element(
34///         Image::builder()
35///             .image_url("https://image.freepik.com/free-photo/red-drawing-pin_1156-445.jpg")
36///             .alt_text("images")
37///             .build()?
38///     )
39///     .element(mrkdwn!("Location: **Dogpatch**")?)
40///     .build()?;
41///
42/// let expected = serde_json::json!({
43///     "type": "context",
44///     "elements": [
45///         {
46///             "type": "image",
47///             "image_url": "https://image.freepik.com/free-photo/red-drawing-pin_1156-445.jpg",
48///             "alt_text": "images"
49///         },
50///         {
51///             "type": "mrkdwn",
52///             "text": "Location: **Dogpatch**"
53///         }
54///     ]
55/// });
56///
57/// let json = serde_json::to_value(context).unwrap();
58///
59/// assert_eq!(json, expected);
60/// #     Ok(())
61/// # }
62/// # fn main() {
63/// #     try_main().unwrap()
64/// # }
65/// ```
66#[derive(Debug, Clone, Serialize, PartialEq, Builder)]
67#[serde(tag = "type", rename = "context")]
68pub struct Context {
69    #[builder(push_item = "element", validate("required", "list::max_item_10"))]
70    pub(crate) elements: Option<Vec<ContextElement>>,
71
72    #[serde(skip_serializing_if = "Option::is_none")]
73    #[builder(validate("text::max_255"))]
74    pub(crate) block_id: Option<String>,
75}
76
77/// Objects that can be an element of the [Context]'s elements field.
78#[derive(Debug, Clone, Serialize, PartialEq)]
79#[serde(untagged)]
80pub enum ContextElement {
81    /// [Image element](https://docs.slack.dev/reference/block-kit/block-elements/image-element)
82    /// representation
83    Image(Box<Image>),
84
85    /// [Text object](https://docs.slack.dev/reference/block-kit/composition-objects/text-object)
86    /// representation
87    Text(Box<TextContent>),
88}
89
90impl From<Image> for ContextElement {
91    fn from(value: Image) -> Self {
92        Self::Image(Box::new(value))
93    }
94}
95
96impl<T> From<T> for ContextElement
97where
98    TextContent: From<T>,
99{
100    fn from(value: T) -> Self {
101        Self::Text(Box::new(TextContent::from(value)))
102    }
103}
104
105#[cfg(test)]
106mod tests {
107    use super::*;
108    use crate::composition_objects::test_helpers::*;
109    use crate::errors::*;
110
111    #[test]
112    fn it_implements_builder() {
113        let expected = Context {
114            block_id: Some("context_0".into()),
115            elements: Some(vec![mrkdwn_text("foo").into()]),
116        };
117
118        let val = Context::builder()
119            .set_block_id(Some("context_0"))
120            .set_elements(Some(vec![mrkdwn_text("foo").into()]))
121            .build()
122            .unwrap();
123
124        assert_eq!(val, expected);
125
126        let val = Context::builder()
127            .block_id("context_0")
128            .elements(vec![mrkdwn_text("foo").into()])
129            .build()
130            .unwrap();
131
132        assert_eq!(val, expected);
133    }
134
135    #[test]
136    fn it_implements_push_item_method() {
137        let expected = Context {
138            block_id: None,
139            elements: Some(vec![mrkdwn_text("foo").into()]),
140        };
141
142        let val = Context::builder()
143            .element(mrkdwn_text("foo"))
144            .build()
145            .unwrap();
146
147        assert_eq!(val, expected);
148    }
149
150    #[test]
151    fn it_requires_elements_field() {
152        let err = Context::builder().build().unwrap_err();
153        assert_eq!(err.object(), "Context");
154
155        let errors = err.field("elements");
156        assert!(errors.includes(ValidationErrorKind::Required));
157    }
158
159    #[test]
160    fn it_requires_elements_list_size_less_than_10() {
161        let elements: Vec<ContextElement> = (0..11).map(|_| mrkdwn_text("foo").into()).collect();
162        let err = Context::builder().elements(elements).build().unwrap_err();
163        assert_eq!(err.object(), "Context");
164
165        let errors = err.field("elements");
166        assert!(errors.includes(ValidationErrorKind::MaxArraySize(10)));
167    }
168
169    #[test]
170    fn it_requires_block_id_less_than_255_characters_long() {
171        let err = Context::builder()
172            .block_id("a".repeat(256))
173            .element(mrkdwn_text("foo"))
174            .build()
175            .unwrap_err();
176        assert_eq!(err.object(), "Context");
177
178        let errors = err.field("block_id");
179        assert!(errors.includes(ValidationErrorKind::MaxTextLength(255)));
180    }
181}
slack_messaging/blocks/context.rs

slack_messaging/blocks/
context.rs
