Fix Dockerfile and PDF generation

Dockerfile

@@ -6,25 +6,23 @@ EXPOSE 5000
 RUN pip install --no-cache-dir gunicorn==19.9.0
 
 RUN apt-get update && \
-  apt-get install --yes chromium=73.0.3683.75-1~deb9u1
+  apt-get install --yes --no-install-recommends chromium=73.0.3683.75-1~deb9u1
 
-ARG user=jenkins
-ARG group=jenkins
 ARG uid=1000
 ARG gid=1000
 
-RUN groupadd -g ${gid} ${group} && \
-  useradd -u ${uid} -g ${gid} --no-create-home --shell /bin/bash ${user}
+RUN groupadd -g ${gid} validata && \
+  useradd -u ${uid} -g ${gid} --create-home --shell /bin/bash validata
 
-WORKDIR /app
+# Cf https://bugs.chromium.org/p/chromium/issues/detail?id=638180 and https://blog.ineat-conseil.fr/2018/08/executer-karma-avec-chromeheadless-dans-un-conteneur-docker/
+USER validata
 
-COPY requirements.txt .
-RUN pip install --no-cache-dir --requirement requirements.txt
+WORKDIR /app
 
-COPY . .
-RUN pip install --no-cache-dir --editable .
+COPY --chown=validata:validata requirements.txt .
+RUN pip install --no-cache-dir --user --requirement requirements.txt --no-warn-script-location
 
-# Cf https://bugs.chromium.org/p/chromium/issues/detail?id=638180
-USER ${user}
+COPY --chown=validata:validata . .
+RUN pip install --no-cache-dir --user --editable .
 
-CMD gunicorn --bind 0.0.0.0:5000 validata_ui:app
\ No newline at end of file
+CMD gunicorn --workers 4 --bind 0.0.0.0:5000 validata_ui:app

validata_ui/views.py

@@ -478,7 +478,7 @@ def pdf_report():
         tmp_pdf_report = Path(tmpfile.name)
 
     # Use chromium headless to generate PDF from validation report page
-    cmd = ['chromium', '--headless', '--disable-gpu',
+    cmd = ['chromium', '--headless', '--no-sandbox',
            '--print-to-pdf={}'.format(str(tmp_pdf_report)), validation_url]
     result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
     if result.returncode != 0: