feat: Add support for math notation in kramdown-rfc

This change adds utftex and tex2svg.
Fixes #352

Dockerfile

@@ -3,6 +3,7 @@ LABEL maintainer="Kesara Rathnayake <kesara@staff.ietf.org>"
 
 ENV DEBIAN_FRONTEND noninteractive
 ENV PATH=$PATH:./node_modules/.bin
+ENV LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH
 # Disable local file read for kramdown-rfc
 ENV KRAMDOWN_SAFE=1
 
@@ -12,22 +13,26 @@ SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 
 RUN apt-get update && \
     apt-get install -y \
+        autoconf \
         software-properties-common \
         gcc \
         wget \
         ruby \
         python3.10 \
         python3-pip \
+        pkg-config \
+        libtool \
         libpango-1.0-0 \
         wdiff \
         rfcdiff \
         npm \
         gawk \
         bison \
         flex && \
-     rm -rf /var/lib/apt/lists/* /var/log/dpkg.log && \
-     apt-get autoremove -y && \
-     apt-get clean -y
+    rm -rf /var/lib/apt/lists/* /var/log/dpkg.log && \
+    apt-get autoremove -y && \
+    apt-get clean -y && \
+    ldconfig
 
 # Install required fonts
 RUN mkdir -p ~/.fonts/opentype && \
@@ -63,6 +68,16 @@ RUN arch=$(arch | sed s/aarch64/arm64/ | sed s/x86_64/amd64/) && \
     tar zxf mmark_*.tgz -C /bin/ && \
     rm mmark_*.tgz
 
+# Install utftex
+RUN export UTFTEX=libtexprintf-1.25 && \
+    wget -q https://github.com/bartp5/libtexprintf/archive/refs/tags/v1.25.zip && \
+    unzip -q v1.25.zip -d /tmp/ && \
+    cd /tmp/$UTFTEX && \
+    ./autogen.sh && \
+    ./configure && \
+    make install && \
+    rm -r /tmp/$UTFTEX /usr/src/app/v1.25.zip
+
 COPY Gemfile Gemfile.lock LICENSE README.md api.yml constraints.txt package-lock.json package.json requirements.txt .
 COPY at ./at
 

api.yml

@@ -860,3 +860,9 @@ paths:
                       rfcdiff:
                         type: string
                         description: rfcdiff version
+                      utftex:
+                        type: string
+                        description: utftex version
+                      tex2svg:
+                        type: string
+                        description: tex2svg version

at/api.py

@@ -22,8 +22,8 @@
 from at.utils.version import (
         get_aasvg_version, get_idnits_version, get_id2xml_version,
         get_iddiff_version, get_mmark_version, get_kramdown_rfc_version,
-        get_rfcdiff_version, get_svgcheck_version, get_weasyprint_version,
-        get_xml2rfc_version)
+        get_rfcdiff_version, get_svgcheck_version, get_tex2svg_version,
+        get_utftex_version, get_weasyprint_version, get_xml2rfc_version)
 
 BAD_REQUEST = 400
 VERSION_INFORMATION = {
@@ -37,6 +37,8 @@
         'aasvg': get_aasvg_version(),
         'svgcheck': get_svgcheck_version(),
         'rfcdiff': get_rfcdiff_version(),
+        'tex2svg': get_tex2svg_version(),
+        'utftex': get_utftex_version(),
         'bap': '1.4'}   # bap does not provide a switch to get version
 
 bp = Blueprint('api', __name__, url_prefix='/api')

at/utils/version.py

@@ -1,5 +1,6 @@
 from logging import getLogger
 from subprocess import run as proc_run, CalledProcessError
+from re import search
 
 from weasyprint import __version__ as weasyprint_version
 from xml2rfc import __version__ as xml2rfc_version
@@ -132,3 +133,38 @@ def get_rfcdiff_version(logger=getLogger()):
         logger.info('rfcdiff error: {}'.format(
             output.stderr.decode('utf-8')))
         return None
+
+
+def get_tex2svg_version(logger=getLogger()):
+    '''Return tex2svg version'''
+
+    output = proc_run(args=['tex2svg', '--version'], capture_output=True)
+
+    try:
+        output.check_returncode()
+        return output.stdout.decode('utf-8').strip()
+    except CalledProcessError:  # pragma: no cover
+        logger.info('tex2svg error: {}'.format(
+            output.stderr.decode('utf-8')))
+        return None
+
+
+def get_utftex_version(logger=getLogger()):
+    '''Return utftex version'''
+
+    output = proc_run(args=['utftex', '--version'], capture_output=True)
+
+    try:
+        output.check_returncode()
+        match = search(
+                    r'This is utftex version (\d+\.\d+)',
+                    output.stdout.decode('utf-8').strip())
+        if match:
+            return match.group(1)
+        else:
+            logger.info('utftex error: Could not find version.')
+            return None
+    except CalledProcessError:  # pragma: no cover
+        logger.info('utftex error: {}'.format(
+            output.stderr.decode('utf-8')))
+        return None