Make 'image' crate optional (#764)

Discussion at #763.

docx-core/Cargo.toml

@@ -18,7 +18,8 @@ name = "docx_rs"
 path = "src/lib.rs"
 
 [features]
-wasm = ["wasm-bindgen", "ts-rs"]
+default = ["image"]
+wasm = ["wasm-bindgen", "ts-rs", "image"]
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -29,7 +30,7 @@ zip = { version = "0.6.3", default-features = false, features = ["deflate"] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = {version = "1.0" }
 base64 = "0.13.1"
-image = { version = "0.24.4", default-features = false, features=["gif", "jpeg", "png", "bmp", "tiff"] }
+image = { version = "0.24.4", default-features = false, features=["gif", "jpeg", "png", "bmp", "tiff"], optional = true }
 wasm-bindgen = { version = "0.2.78", optional = true }
 ts-rs = { version = "6.1", optional = true }
 

docx-core/src/documents/elements/drawing.rs

@@ -163,12 +163,8 @@ mod tests {
 
     #[test]
     fn test_drawing_build_with_pic() {
-        use std::io::Read;
+        let pic = Pic::new_with_dimensions(Vec::new(), 320, 240);
-
+        let d = Drawing::new().pic(pic).build();
-        let mut img = std::fs::File::open("../images/cat_min.jpg").unwrap();
-        let mut buf = Vec::new();
-        let _ = img.read_to_end(&mut buf).unwrap();
-        let d = Drawing::new().pic(Pic::new(&buf)).build();
         assert_eq!(
             str::from_utf8(&d).unwrap(),
             r#"<w:drawing>
@@ -212,12 +208,8 @@ mod tests {
 
     #[test]
     fn test_drawing_build_with_pic_overlap() {
-        use std::io::Read;
+        let pic = Pic::new_with_dimensions(Vec::new(), 320, 240).overlapping();
-
+        let d = Drawing::new().pic(pic).build();
-        let mut img = std::fs::File::open("../images/cat_min.jpg").unwrap();
-        let mut buf = Vec::new();
-        let _ = img.read_to_end(&mut buf).unwrap();
-        let d = Drawing::new().pic(Pic::new(&buf).overlapping()).build();
         assert_eq!(
             str::from_utf8(&d).unwrap(),
             r#"<w:drawing>
@@ -262,12 +254,7 @@ mod tests {
 
     #[test]
     fn test_drawing_build_with_pic_align_right() {
-        use std::io::Read;
+        let mut pic = Pic::new_with_dimensions(Vec::new(), 320, 240).floating();
-
-        let mut img = std::fs::File::open("../images/cat_min.jpg").unwrap();
-        let mut buf = Vec::new();
-        let _ = img.read_to_end(&mut buf).unwrap();
-        let mut pic = Pic::new(&buf).floating();
         pic = pic.relative_from_h(RelativeFromHType::Column);
         pic = pic.relative_from_v(RelativeFromVType::Paragraph);
         pic = pic.position_h(DrawingPosition::Align(PicAlign::Right));
@@ -323,12 +310,7 @@ mod tests {
 
     #[test]
     fn test_issue686() {
-        use std::io::Read;
+        let pic = Pic::new_with_dimensions(Vec::new(), 320, 240)
-
-        let mut img = std::fs::File::open("../images/cat_min.jpg").unwrap();
-        let mut buf = Vec::new();
-        let _ = img.read_to_end(&mut buf).unwrap();
-        let pic = Pic::new(&buf)
             .size(320 * 9525, 240 * 9525)
             .floating()
             .offset_x(300 * 9525)

docx-core/src/documents/elements/pic.rs

@@ -1,4 +1,3 @@
-use image::*;
 use serde::Serialize;
 
 use crate::documents::*;
@@ -50,18 +49,28 @@ pub struct Pic {
 }
 
 impl Pic {
+    #[cfg(feature = "image")]
+    /// Make a `Pic`.
+    ///
+    /// Converts the passed image to PNG internally and computes its size.
     pub fn new(buf: &[u8]) -> Pic {
-        let id = create_pic_rid(generate_pic_id());
+        let img = ::image::load_from_memory(buf).expect("Should load image from memory.");
-        let dimg = image::load_from_memory(buf).expect("Should load image from memory.");
+        let (w, h) = ::image::GenericImageView::dimensions(&img);
-        let size = dimg.dimensions();
+        let mut buf = std::io::Cursor::new(vec![]);
-        let mut image = std::io::Cursor::new(vec![]);
+        img.write_to(&mut buf, ::image::ImageFormat::Png)
-        // For now only png supported
-        dimg.write_to(&mut image, ImageFormat::Png)
             .expect("Unable to write dynamic image");
+        Self::new_with_dimensions(buf.into_inner(), w, h)
+    }
+
+    /// Make a `Pic` element. For now only PNG is supported.
+    ///
+    /// Use [Pic::new] method, to call `image` crate do conversion for you.
+    pub fn new_with_dimensions(buffer: Vec<u8>, width_px: u32, height_px: u32) -> Pic {
+        let id = create_pic_rid(generate_pic_id());
         Self {
             id,
-            image: image.into_inner(),
+            image: buffer,
-            size: (from_px(size.0), from_px(size.1)),
+            size: (from_px(width_px), from_px(height_px)),
             position_type: DrawingPositionType::Inline,
             simple_pos: false,
             simple_pos_x: 0,
@@ -236,12 +245,7 @@ mod tests {
 
     #[test]
     fn test_pic_build() {
-        use std::io::Read;
+        let b = Pic::new_with_dimensions(Vec::new(), 320, 240).build();
-
-        let mut img = std::fs::File::open("../images/cat_min.jpg").unwrap();
-        let mut buf = Vec::new();
-        let _ = img.read_to_end(&mut buf).unwrap();
-        let b = Pic::new(&buf).build();
         assert_eq!(
             str::from_utf8(&b).unwrap(),
             r#"<pic:pic xmlns:pic="http://schemas.openxmlformats.org/drawingml/2006/picture">

docx-core/src/documents/mod.rs

@@ -43,7 +43,6 @@ mod xml_docx;
 pub(crate) use build_xml::BuildXML;
 pub(crate) use history_id::HistoryId;
 pub(crate) use hyperlink_id::*;
-use image::ImageFormat;
 pub(crate) use paragraph_id::*;
 pub(crate) use paragraph_property_change_id::ParagraphPropertyChangeId;
 pub(crate) use pic_id::*;
@@ -246,15 +245,22 @@ impl Docx {
         path: impl Into<String>,
         buf: Vec<u8>,
     ) -> Self {
+        #[cfg(feature = "image")]
         if let Ok(dimg) = image::load_from_memory(&buf) {
             let mut png = std::io::Cursor::new(vec![]);
             // For now only png supported
-            dimg.write_to(&mut png, ImageFormat::Png)
+            dimg.write_to(&mut png, image::ImageFormat::Png)
                 .expect("Unable to write dynamic image");
 
             self.images
                 .push((id.into(), path.into(), Image(buf), Png(png.into_inner())));
         }
+        #[cfg(not(feature = "image"))]
+        // without 'image' crate we can only test for PNG file signature
+        if buf.starts_with(&[137, 80, 78, 71, 13, 10, 26, 10]) {
+            self.images
+              .push((id.into(), path.into(), Image(buf.clone()), Png(buf)));
+        }
         self
     }