feat: show download size on files read from disk

Cargo.lock

@@ -43,13 +43,13 @@ dependencies = [
 
 [[package]]
 name = "async-trait"
-version = "0.1.59"
+version = "0.1.68"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "31e6e93155431f3931513b243d371981bb2770112b370c82745a1d19d2f99364"
+checksum = "b9ccdd8f2a161be9bd5c023df56f1b2a0bd1d83872ae53b71a84a12c9bf6e842"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 1.0.104",
+ "syn 2.0.22",
 ]
 
 [[package]]
@@ -135,6 +135,7 @@ dependencies = [
  "async-recursion",
  "axum",
  "bytes",
+ "futures",
  "hyper",
  "log",
  "pretty_env_logger",
@@ -213,6 +214,21 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23342abe12aba583913b2e62f22225ff9c950774065e4bfb61a19cd9770fec40"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.28"
@@ -220,6 +236,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "955518d47e09b25bbebc7a18df10b81f0c766eaf4c4f1cccef2fca5f2a4fb5f2"
 dependencies = [
  "futures-core",
+ "futures-sink",
 ]
 
 [[package]]
@@ -228,6 +245,17 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4bca583b7e26f571124fe5b7561d49cb2868d79116cfa0eefce955557c6fee8c"
 
+[[package]]
+name = "futures-executor"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ccecee823288125bd88b4d7f565c9e58e41858e47ab72e8ea2d64e93624386e0"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-io"
 version = "0.3.28"
@@ -263,9 +291,13 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "26b01e40b772d54cf6c6d721c1d1abd0647a0106a12ecaa1c186273392a69533"
 dependencies = [
+ "futures-channel",
  "futures-core",
+ "futures-io",
  "futures-macro",
+ "futures-sink",
  "futures-task",
+ "memchr",
  "pin-project-lite",
  "pin-utils",
  "slab",

Cargo.toml

@@ -14,6 +14,7 @@ bytes = "1"
 rand = "0.8.5"
 async-recursion = "1.0.0"
 walkdir = "2"
+futures = "0.3"
 log = "0.4"
 pretty_env_logger = "0.5.0"
 archived = { path = "./archived" }

src/view.rs

@@ -10,8 +10,8 @@ use axum::{
 };
 
 use bytes::Bytes;
-use hyper::StatusCode;
+use hyper::{http::HeaderValue, StatusCode};
-use tokio::fs::File;
+use tokio::{fs::File, runtime::Handle};
 use tokio_util::io::ReaderStream;
 
 pub enum ViewSuccess {
@@ -20,7 +20,7 @@ pub enum ViewSuccess {
 }
 
 pub enum ViewError {
-    NotFound, // 404
+    NotFound,            // 404
     InternalServerError, // 500
 }
 
@@ -28,20 +28,67 @@ impl IntoResponse for ViewSuccess {
     fn into_response(self) -> Response {
         match self {
             ViewSuccess::FromDisk(file) => {
+                // get handle to current runtime
+                // i use this to block on futures here (not async)
+                let handle = Handle::current();
+                let _ = handle.enter();
+
+                // read the metadata of the file on disk
+                // this function isn't async
+                // .. so we have to use handle.block_on() to get the metadata
+                let metadata = futures::executor::block_on(file.metadata());
+
+                // if we error then return 500
+                if metadata.is_err() {
+                    error!("failed to read metadata from disk");
+                    return ViewError::InternalServerError.into_response();
+                }
+
+                // unwrap (which we know is safe) and read the file size as a string
+                let metadata = metadata.unwrap();
+                let len_str = metadata.len().to_string();
+
+                debug!("file is {} bytes on disk", &len_str);
+
+                // HeaderValue::from_str will never error if only visible ASCII characters are passed (32-127)
+                // .. so unwrapping this should be fine
+                let content_length = HeaderValue::from_str(&len_str).unwrap();
+
                 // create a streamed body response (we want to stream larger files)
                 let reader = ReaderStream::new(file);
                 let stream = StreamBody::new(reader);
 
-                stream.into_response()
+                // extract mutable headers from the response
+                let mut res = stream.into_response();
+                let headers = res.headers_mut();
+
+                // clear headers, browser can imply content type
+                headers.clear();
+
+                // insert Content-Length header
+                // that way the browser shows how big a file is when it's being downloaded
+                headers.insert("Content-Length", content_length);
+
+                res
             }
             ViewSuccess::FromCache(data) => {
                 // extract mutable headers from the response
-                let mut res = data.into_response();
+                let mut res = data.clone().into_response();
                 let headers = res.headers_mut();
 
                 // clear the headers, let the browser imply it
                 headers.clear();
 
+                /* // we do not need this for FromCache because it works fine
+                // read the length of the data as a string
+                let len_str = data.len().to_string();
+
+                // HeaderValue::from_str will never error if only visible ASCII characters are passed (32-127)
+                // .. so this should be fine
+                let content_length = HeaderValue::from_str(&len_str).unwrap();
+                headers.append("Content-Length", content_length);
+                */
+
                 res
             }
         }
@@ -61,7 +108,7 @@ impl IntoResponse for ViewError {
             ViewError::InternalServerError => {
                 // convert string into response, change status code
                 let mut res = "internal server error!".into_response();
-                *res.status_mut() = StatusCode::NOT_FOUND;
+                *res.status_mut() = StatusCode::INTERNAL_SERVER_ERROR;
 
                 res
             }