bc_envelope/base/
wrap.rs

1use anyhow::{ bail, Result };
2
3use crate::{ Envelope, Error };
4
5use super::envelope::EnvelopeCase;
6
7/// Support for wrapping and unwrapping envelopes.
8impl Envelope {
9    /// Returns a new envelope which wraps the current envelope.
10    ///
11    /// Wrapping an envelope allows you to treat an envelope (including its assertions)
12    /// as a single unit, making it possible to add assertions about the envelope as a whole.
13    ///
14    /// # Examples
15    ///
16    /// ```
17    /// # use bc_envelope::prelude::*;
18    /// # use indoc::indoc;
19    /// // Create an envelope with an assertion
20    /// let envelope = Envelope::new("Hello.")
21    ///     .add_assertion("language", "English");
22    ///
23    /// // Wrap it to add an assertion about the envelope as a whole
24    /// let wrapped = envelope.wrap_envelope()
25    ///     .add_assertion("authenticated", true);
26    ///
27    /// assert_eq!(wrapped.format(), indoc! {r#"
28    /// {
29    ///     "Hello." [
30    ///         "language": "English"
31    ///     ]
32    /// } [
33    ///     "authenticated": true
34    /// ]
35    /// "#}.trim());
36    /// ```
37    pub fn wrap_envelope(&self) -> Self {
38        Self::new_wrapped(self.clone())
39    }
40
41    /// Unwraps and returns the inner envelope.
42    ///
43    /// This extracts the envelope contained within a wrapped envelope.
44    ///
45    /// # Errors
46    ///
47    /// Returns `EnvelopeError::NotWrapped` if this is not a wrapped envelope.
48    ///
49    /// # Examples
50    ///
51    /// ```
52    /// # use bc_envelope::prelude::*;
53    /// // Create an envelope and wrap it
54    /// let envelope = Envelope::new("Hello.");
55    /// let wrapped = envelope.wrap_envelope();
56    ///
57    /// // Unwrap to get the original envelope
58    /// let unwrapped = wrapped.unwrap_envelope().unwrap();
59    /// assert_eq!(unwrapped.format_flat(), r#""Hello.""#);
60    /// ```
61    pub fn unwrap_envelope(&self) -> Result<Self> {
62        match self.subject().case() {
63            EnvelopeCase::Wrapped { envelope, .. } => Ok(envelope.clone()),
64            _ => bail!(Error::NotWrapped),
65        }
66    }
67}
bc_envelope/base/wrap.rs

bc_envelope/base/
wrap.rs
