Use media type hint when processing uploaded media attachment

docs/openapi.yaml

@@ -639,6 +639,32 @@ paths:
             application/json:
               schema:
                 $ref: '#/components/schemas/Instance'
+  /api/v1/media:
+    post:
+      summary: Create an attachment to be used with a new post.
+      security:
+        - tokenAuth: []
+      requestBody:
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                file:
+                  description: File encoded as base64.
+                  type: string
+                media_type:
+                  description: Media type.
+                  type: string
+                  nullable: true
+                  example: image/jpeg
+      responses:
+        200:
+          description: Successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Attachment'
   /api/v1/notifications:
     get:
       summary: Notifications concerning the user.

src/mastodon_api/media/types.rs

@@ -2,16 +2,16 @@ use serde::{Deserialize, Serialize};
 use uuid::Uuid;
 
 use crate::models::attachments::types::{
-    DbMediaAttachment,
     AttachmentType,
+    DbMediaAttachment,
 };
 use crate::utils::files::get_file_url;
 
-/// https://docs.joinmastodon.org/methods/statuses/media/
 #[derive(Deserialize)]
 pub struct AttachmentCreateData {
-    // base64-encoded file
+    // base64-encoded file (not comtaible with Mastodon)
     pub file: String,
+    pub media_type: Option<String>,
 }
 
 /// https://docs.joinmastodon.org/entities/attachment/

src/mastodon_api/media/views.rs

@@ -1,3 +1,4 @@
+/// https://docs.joinmastodon.org/methods/media/#v1
 use actix_web::{post, web, HttpResponse, Scope};
 use actix_web_httpauth::extractors::bearer::BearerAuth;
 
@@ -20,6 +21,7 @@ async fn create_attachment_view(
     let current_user = get_current_user(db_client, auth.token()).await?;
     let (file_name, media_type) = save_b64_file(
         &attachment_data.file,
+        attachment_data.media_type.clone(),
         &config.media_dir(),
     )?;
     let db_attachment = create_attachment(

src/mastodon_api/uploads.rs

@@ -33,13 +33,14 @@ impl From<UploadError> for HttpError {
 
 pub fn save_b64_file(
     b64data: &str,
+    maybe_media_type: Option<String>,
     output_dir: &Path,
 ) -> Result<(String, Option<String>), UploadError> {
     let data = base64::decode(b64data)?;
     if data.len() > UPLOAD_MAX_SIZE {
         return Err(UploadError::TooLarge);
     };
-    Ok(save_file(data, output_dir, None)?)
+    Ok(save_file(data, output_dir, maybe_media_type)?)
 }
 
 pub fn save_validated_b64_file(