add cpp api reference (#618)

Summary: Pull Request resolved: #618

Differential Revision: D49924199

Author: JacobSzwejbka

.ci/docker/common/install_docs_reqs.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+set -ex
+
+if [ -n "$KATEX" ]; then
+  apt-get update
+  # Ignore error if gpg-agent doesn't exist (for Ubuntu 16.04)
+  apt-get install -y gpg-agent || :
+
+  curl --retry 3 -sL https://deb.nodesource.com/setup_16.x | sudo -E bash -
+  sudo apt-get install -y nodejs
+
+  curl --retry 3 -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
+  echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
+
+  apt-get update
+  apt-get install -y --no-install-recommends yarn
+  yarn global add katex --prefix /usr/local
+
+  sudo apt-get -y install doxygen
+
+  apt-get autoclean && apt-get clean
+  rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+
+fi

.ci/docker/requirements-ci.txt

@@ -15,8 +15,11 @@ hypothesis==6.84.2
 parameterized==0.9.0
 
 # Doc build requirements
-sphinx==5.0.0
+sphinx==4.5.0
 sphinx-gallery
+breathe==4.35.0
+exhale==0.3.6
+docutils==0.16
 matplotlib
 # PyTorch Theme
 -e git+https://github.com/pytorch/pytorch_sphinx_theme.git#egg=pytorch_sphinx_theme

.ci/docker/ubuntu/Dockerfile

@@ -38,6 +38,11 @@ COPY ./common/install_conda.sh install_conda.sh
 COPY ./common/utils.sh utils.sh
 RUN bash ./install_conda.sh && rm install_conda.sh utils.sh /opt/conda/requirements-ci.txt /opt/conda/conda-env-ci.txt
 
+# Install katex
+ARG KATEX
+COPY ./common/install_docs_reqs.sh install_docs_reqs.sh
+RUN bash ./install_docs_reqs.sh && rm install_docs_reqs.sh
+
 ARG LINTRUNNER
 # Install lintrunner if needed
 COPY ./common/install_linter.sh install_linter.sh