Use heredoc in Containerfile

https://docs.docker.com/reference/dockerfile/#here-documents

Containerfile

@@ -4,33 +4,48 @@ ARG FEDORA_MAJOR_VERSION=40
 
 FROM quay.io/fedora/fedora:${FEDORA_MAJOR_VERSION} AS builder
 
-RUN cd /tmp && \
-    curl -fLs 'https://descargas.cert.fnmt.es/Linux/configuradorfnmt-4.0.6-0.x86_64.rpm' -O && \
-    echo 'a2c564ddc1f5e87b1c47afc196a7ef1d6b4844e59fc8b15cd828250dc9d43f03  configuradorfnmt-4.0.6-0.x86_64.rpm' | sha256sum --check --status && \
-    dnf install -y rpm-build cpio --setopt=install_weak_deps=False && \
-    rpm2cpio configuradorfnmt-*.x86_64.rpm | cpio -dium -D src ; \
-    rm -rf src/usr/lib64/configuradorfnmt/jre ; \
-    sed -i 's|^Exec=.*$|Exec=java -classpath /usr/lib64/configuradorfnmt/configuradorfnmt.jar:bcpkix-fips.jar:bc-fips.jar es.gob.fnmt.cert.certrequest.CertRequest %u|' src/usr/share/applications/configuradorfnmt.desktop ; \
-    printf '#!/usr/bin/env sh\njava -classpath /usr/lib64/configuradorfnmt/configuradorfnmt.jar:bcpkix-fips.jar:bc-fips.jar es.gob.fnmt.cert.certrequest.CertRequest "$@"\n' > src/usr/bin/configuradorfnmt ; \
-    rpm -qpi configuradorfnmt-*.x86_64.rpm > rpm.spec ; \
-    sed -i -e '/^Architecture/d' -e '/^Install Date/d' -e '/^Size/d' -e '/^Signature/d' -e '/^Build /d' -e '/^Description/,+1d' rpm.spec ; \
-    printf 'BuildArch   : noarch\nBuildRoot   : %s/src\n\n%%description\n%s\n\n%%files\n' "${PWD}" 'Utilidad FNMT para la solicitud e instalación de certificados desde la página web de FNMT-RCM.' >> rpm.spec ; \
-    find "${PWD}/src" -type f -printf '/%P\n' >> rpm.spec ; \
-    rpmbuild --define "_topdir ${PWD}/rpmbuild" --buildroot="${PWD}/src" -bb rpm.spec
+WORKDIR /tmp
+RUN <<-'EOT' bash
+	set -u
+
+	dnf install -y rpm-build cpio --setopt=install_weak_deps=False && \
+
+	curl -fLs 'https://descargas.cert.fnmt.es/Linux/configuradorfnmt-4.0.6-0.x86_64.rpm' -O
+	echo 'a2c564ddc1f5e87b1c47afc196a7ef1d6b4844e59fc8b15cd828250dc9d43f03  configuradorfnmt-4.0.6-0.x86_64.rpm' | sha256sum --check --status
+
+	rpm2cpio configuradorfnmt-*.x86_64.rpm | cpio -dium -D src
+
+	rm -rf src/usr/lib64/configuradorfnmt/jre
+	sed -i 's|^Exec=.*$|Exec=java -classpath /usr/lib64/configuradorfnmt/configuradorfnmt.jar:bcpkix-fips.jar:bc-fips.jar es.gob.fnmt.cert.certrequest.CertRequest %u|' src/usr/share/applications/configuradorfnmt.desktop
+	printf '#!/usr/bin/env sh\njava -classpath /usr/lib64/configuradorfnmt/configuradorfnmt.jar:bcpkix-fips.jar:bc-fips.jar es.gob.fnmt.cert.certrequest.CertRequest "$@"\n' > src/usr/bin/configuradorfnmt
+
+	rpm -qpi configuradorfnmt-*.x86_64.rpm > rpm.spec
+	sed -i -e '/^Architecture/d' -e '/^Install Date/d' -e '/^Size/d' -e '/^Signature/d' -e '/^Build /d' -e '/^Description/,+1d' rpm.spec
+	printf 'BuildArch   : noarch\nBuildRoot   : %s/src\n\n%%description\n%s\n\n%%files\n' "${PWD}" 'Utilidad FNMT para la solicitud e instalación de certificados desde la página web de FNMT-RCM.' >> rpm.spec
+	find "${PWD}/src" -type f -printf '/%P\n' >> rpm.spec
+
+	rpmbuild --define "_topdir ${PWD}/rpmbuild" --buildroot="${PWD}/src" -bb rpm.spec
+EOT
 
 FROM ${FEDORA_BASE}${FEDORA_VARIANT}:${FEDORA_MAJOR_VERSION}
 
 COPY --from=builder /tmp/rpmbuild/RPMS/noarch/configuradorfnmt-*.noarch.rpm /tmp
 
-RUN cd /tmp && \
-    curl -fLs 'https://estaticos.redsara.es/comunes/autofirma/currentversion/AutoFirma_Linux_Fedora.zip' -O && \
-    echo '86a3b4673ce78663ab996aa542a2bd93f9e666f04e16f4763cccfba6274beb04  AutoFirma_Linux_Fedora.zip' | sha256sum --check --status && \
-    unzip AutoFirma_Linux_Fedora.zip && \
-    rpm-ostree install java-17-openjdk && \
-    for bin in /usr/lib/jvm/java-17-openjdk*/bin/*; do \
-        ln -s "${bin}" /etc/alternatives/ && \
-        ln -s /etc/alternatives/"$(basename "${bin}")" /usr/bin/; \
-    done && \
-    rpm-ostree install autofirma-*.noarch_FEDORA.rpm configuradorfnmt-*.noarch.rpm && \
-    rpm-ostree cleanup -m && \
-    ostree container commit
+WORKDIR /tmp
+RUN <<-'EOT' bash
+	set -eu
+
+	curl -fLs 'https://estaticos.redsara.es/comunes/autofirma/currentversion/AutoFirma_Linux_Fedora.zip' -O
+	echo '86a3b4673ce78663ab996aa542a2bd93f9e666f04e16f4763cccfba6274beb04  AutoFirma_Linux_Fedora.zip' | sha256sum --check --status
+	unzip AutoFirma_Linux_Fedora.zip
+
+	rpm-ostree install java-17-openjdk
+	rpm-ostree install autofirma-*.noarch_FEDORA.rpm configuradorfnmt-*.noarch.rpm
+
+	for bin in /usr/lib/jvm/java-17-openjdk*/bin/*; do
+		ln -s "${bin}" /etc/alternatives/
+		ln -s /etc/alternatives/"$(basename "${bin}")" /usr/bin/
+	done
+
+	rpm-ostree cleanup -m && ostree container commit
+EOT