diff options
Diffstat (limited to 'template/src/additional_cid.rs')
-rw-r--r-- | template/src/additional_cid.rs | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/template/src/additional_cid.rs b/template/src/additional_cid.rs new file mode 100644 index 0000000..eecf2e7 --- /dev/null +++ b/template/src/additional_cid.rs @@ -0,0 +1,60 @@ +use std::collections::{ + HashMap, HashSet +}; + +use serde::{Serialize, Serializer}; + +use mail_core::Resource; +use mail_headers::header_components::ContentId; + +pub struct AdditionalCIds<'a> { + additional_resources: &'a [&'a HashMap<String, Resource>] +} + +impl<'a> AdditionalCIds<'a> { + + /// Creates a new `AdditionalCIds` instance. + /// + /// All resources in the all hash maps have to be loaded to the + /// `Data` or `EncData` variants or using `get` can panic. + pub(crate) fn new(additional_resources: &'a [&'a HashMap<String, Resource>]) -> Self { + AdditionalCIds { additional_resources } + } + + + /// Returns the content id associated with the given name. + /// + /// If multiple of the maps used to create this type contain the + /// key the first match is returned and all later ones are ignored. + /// + /// # Panic + /// + /// If the resource exists but is not loaded (i.e. has no content id) + /// this will panic as this can only happen if there is a bug in the + /// mail code, or this type was used externally. + pub fn get(&self, name: &str) -> Option<&ContentId> { + for possible_source in self.additional_resources { + if let Some(res) = possible_source.get(name) { + return Some(res.content_id().expect("all resources should be loaded/have a content id")); + } + } + return None; + } +} + +impl<'a> Serialize for AdditionalCIds<'a> { + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> + where S: Serializer + { + let mut existing_keys = HashSet::new(); + serializer.collect_map( + self.additional_resources + .iter() + .flat_map(|m| m.iter().map(|(k, resc)| { + (k, resc.content_id().expect("all resources should be loaded/have a content id")) + })) + .filter(|key| existing_keys.insert(key.to_owned())) + ) + } +} + |