Reimplement GetFile request

src/bot/api.rs

@@ -2,7 +2,7 @@ use crate::{
     Bot,
     requests::{
         json, multipart,
-        payloads::{GetMe, GetUpdates, SendMessage, SendAnimation}
+        payloads::{GetMe, GetUpdates, SendMessage, SendAnimation, GetFile}
     },
     types::{ChatId, InputFile},
 };
@@ -48,4 +48,14 @@ impl Bot {
     {
         multipart::Request::new(self, SendAnimation::new(chat_id, animation))
     }
+
+    /// For tg-method documentation see [`GetFile`]
+    ///
+    /// [`GetFile`]: crate::requests::payloads::GetFile
+    pub fn get_file<F>(&self, file_id: F) -> json::Request<GetFile>
+    where
+        F: Into<String>,
+    {
+        json::Request::new(self, GetFile::new(file_id))
+    }
 }

src/requests/mod.rs

@@ -66,10 +66,14 @@ pub mod payloads {
 
     mod send_animation;
 
+    mod get_file;
+
     pub use self::{
         get_me::GetMe,
         send_message::SendMessage,
 
         send_animation::SendAnimation,
+
+        get_file::GetFile,
     };
 }

src/requests/payloads/get_file.rs

@@ -0,0 +1,68 @@
+use crate::{
+    bot::Bot,
+    network,
+    requests::{json, Method},
+    types::File,
+};
+use crate::requests::dynamic;
+
+/// Use this method to get basic info about a file and prepare it for
+/// downloading.
+///
+/// For the moment, bots can download files of up to `20MB` in size.
+///
+/// On success, a [`File`] object is returned.
+///
+/// The file can then be downloaded via the link
+/// `https://api.telegram.org/file/bot<token>/<file_path>`, where `<file_path>`
+/// is taken from the response. It is guaranteed that the link will be valid
+/// for at least `1` hour. When the link expires, a new one can be requested by
+/// calling [`GetFile`] again.
+///
+/// **Note**: This function may not preserve the original file name and MIME
+/// type. You should save the file's MIME type and name (if available) when the
+/// [`File`] object is received.
+///
+/// [`File`]: crate::types::file
+/// [`GetFile`]: self::GetFile
+#[serde_with_macros::skip_serializing_none]
+#[derive(Debug, PartialEq, Eq, Hash, Clone, Deserialize, Serialize)]
+pub struct GetFile {
+    /// File identifier to get info about
+    pub file_id: String,
+}
+
+impl Method for GetFile {
+    type Output = File;
+
+    const NAME: &'static str = "getFile";
+}
+
+impl json::Payload for GetFile {}
+
+impl dynamic::Payload for GetFile {
+    fn kind(&self) -> dynamic::Kind {
+        dynamic::Kind::Json(serde_json::to_string(self).unwrap())
+    }
+}
+
+impl GetFile {
+    pub fn new<F>(file_id: F) -> Self
+    where
+        F: Into<String>
+    {
+        Self {
+            file_id: file_id.into(),
+        }
+    }
+}
+
+impl json::Request<'_, GetFile> {
+    pub fn file_id<F>(mut self, value: F) -> Self
+    where
+        F: Into<String>,
+    {
+        self.payload.file_id = value.into();
+        self
+    }
+}