chore: pdf ファイルの差分を表示するエンドポイントを作成しています

Dockerfile

@@ -2,17 +2,33 @@
 
 FROM golang:1.21
 
+# Build diff-pdf
+WORKDIR /
+RUN git clone https://github.com/vslavik/diff-pdf.git
+WORKDIR /diff-pdf
+# 参考
+# https://docs.docker.jp/engine/articles/dockerfile_best-practice.html
+RUN apt-get update && \
+    apt-get -y install make automake g++ libglib2.0-dev libpoppler-glib-dev wx-common libwxgtk3.2-dev && \
+    apt-get clean
+RUN ./bootstrap
+RUN ./configure
+RUN make
+# diff-pdf にパスを通す
+ENV PATH=$PATH:/diff-pdf
+
 # Set destination for COPY
 WORKDIR /app
 
 # Download Go modules
 COPY go.mod go.sum ./
-RUN go mod download
 
 # Copy the source code. Note the slash at the end, as explained in
 # https://docs.docker.com/engine/reference/builder/#copy
 COPY ./ ./
 
+RUN go mod download
+
 # Build
 RUN CGO_ENABLED=0 GOOS=linux go build -o /backend