From 5acfffb352a47e052673f7ecc0c87653bc6c8ec4 Mon Sep 17 00:00:00 2001
From: Sebastian Martinez <me@sebastinez.dev>
Date: Tue, 19 Sep 2023 16:00:21 +0200
Subject: [PATCH] httpd: Improve data-uri support

We were just using `strip_prefix` with a hardcoded value, which wasn't
able to adjust to URIs that start with `data:image/png` or other content
and types.

Signed-off-by: Sebastian Martinez <me@sebastinez.dev>
---
 radicle-httpd/src/api.rs             | 29 +++++++++++++++++++-
 radicle-httpd/src/api/v1/projects.rs | 41 +++++++++-------------------
 2 files changed, 41 insertions(+), 29 deletions(-)

diff --git a/radicle-httpd/src/api.rs b/radicle-httpd/src/api.rs
index 037b14ecb..9ec4e331e 100644
--- a/radicle-httpd/src/api.rs
+++ b/radicle-httpd/src/api.rs
@@ -10,13 +10,14 @@ use axum::http::Method;
 use axum::response::{IntoResponse, Json};
 use axum::routing::get;
 use axum::Router;
+use base64::prelude::{Engine, BASE64_STANDARD};
 use serde::{Deserialize, Serialize};
 use serde_json::json;
 use tokio::sync::RwLock;
 use tower_http::cors::{self, CorsLayer};
 
-use radicle::cob::issue;
 use radicle::cob::patch;
+use radicle::cob::{issue, Uri};
 use radicle::identity::Id;
 use radicle::node::routing::Store;
 use radicle::storage::{ReadRepository, ReadStorage};
@@ -204,3 +205,29 @@ mod project {
         pub trackings: usize,
     }
 }
+
+/// A `data:` URI.
+#[derive(Debug, Clone)]
+pub struct DataUri(Vec<u8>);
+
+impl From<DataUri> for Vec<u8> {
+    fn from(value: DataUri) -> Self {
+        value.0
+    }
+}
+
+impl TryFrom<&Uri> for DataUri {
+    type Error = Uri;
+
+    fn try_from(value: &Uri) -> Result<Self, Self::Error> {
+        if let Some(data_uri) = value.as_str().strip_prefix("data:") {
+            let (_, uri_data) = data_uri.split_once(',').ok_or(value.clone())?;
+            let uri_data = BASE64_STANDARD
+                .decode(uri_data)
+                .map_err(|_| value.clone())?;
+
+            return Ok(DataUri(uri_data));
+        }
+        Err(value.clone())
+    }
+}
diff --git a/radicle-httpd/src/api/v1/projects.rs b/radicle-httpd/src/api/v1/projects.rs
index f9eb37d65..b632075a4 100644
--- a/radicle-httpd/src/api/v1/projects.rs
+++ b/radicle-httpd/src/api/v1/projects.rs
@@ -7,7 +7,6 @@ use axum::response::IntoResponse;
 use axum::routing::{get, patch, post};
 use axum::{Json, Router};
 use axum_auth::AuthBearer;
-use base64::prelude::{Engine, BASE64_STANDARD};
 use hyper::StatusCode;
 use radicle_surf::blob::{Blob, BlobRef};
 use serde::{Deserialize, Serialize};
@@ -25,7 +24,7 @@ use radicle_surf::{diff, Glob, Oid, Repository};
 
 use crate::api::error::Error;
 use crate::api::project::Info;
-use crate::api::{self, CobsQuery, Context, PaginationQuery};
+use crate::api::{self, CobsQuery, Context, DataUri, PaginationQuery};
 use crate::axum_extra::{Path, Query};
 
 const CACHE_1_HOUR: &str = "public, max-age=3600, must-revalidate";
@@ -534,18 +533,11 @@ async fn issue_create_handler(
         .embeds
         .into_iter()
         .filter_map(|embed| {
-            if let Some(content) = embed
-                .content
-                .as_str()
-                .strip_prefix("data:content/type;base64,")
-            {
-                return BASE64_STANDARD.decode(content).ok().map(|content| Embed {
-                    name: embed.name,
-                    content,
-                });
-            }
-
-            None
+            let content = TryInto::<DataUri>::try_into(&embed.content).ok()?;
+            Some(Embed {
+                name: embed.name,
+                content: content.into(),
+            })
         })
         .collect();
 
@@ -604,18 +596,11 @@ async fn issue_update_handler(
             let embeds: Vec<Embed> = embeds
                 .into_iter()
                 .filter_map(|embed| {
-                    if let Some(content) = embed
-                        .content
-                        .as_str()
-                        .strip_prefix("data:content/type;base64,")
-                    {
-                        return BASE64_STANDARD.decode(content).ok().map(|content| Embed {
-                            name: embed.name,
-                            content,
-                        });
-                    }
-
-                    None
+                    let content = TryInto::<DataUri>::try_into(&embed.content).ok()?;
+                    Some(Embed {
+                        name: embed.name,
+                        content: content.into(),
+                    })
                 })
                 .collect();
             if let Some(to) = reply_to {
@@ -1848,7 +1833,7 @@ mod routes {
             "embeds": [
               {
                 "name": "example.html",
-                "content": "data:content/type;base64,PGh0bWw+SGVsbG8gV29ybGQhPC9odG1sPg=="
+                "content": "data:image/png;base64,PGh0bWw+SGVsbG8gV29ybGQhPC9odG1sPg=="
               }
             ],
             "assignees": [],
@@ -1924,7 +1909,7 @@ mod routes {
           "embeds": [
             {
               "name": "image.jpg",
-              "content": "data:content/type;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAADElEQVR4nGP4//8/AAX+Av4N70a4AAAAAElFTkSuQmCC"
+              "content": "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAIAAACQd1PeAAAADElEQVR4nGP4//8/AAX+Av4N70a4AAAAAElFTkSuQmCC"
             }
           ],
           "replyTo": CONTRIBUTOR_ISSUE_ID,