Greetings! It has been a while since I’ve posted anything in my systems administration blog. In this post I will describe my process for building a newer version of the Mongo C driver for Enterprise Linux/CentOS 7. These steps were also performed on an Enterprise Linux 6 system, but this post will focus on EL7 solely.

Last year I was asked by a developer to obtain a newer version of the Mongo C Driver for CentOS 7, as the one currently available in the EPEL repository, 1.3.6, does not support the most recent versions of MongoDB. I could not find a guide on the Internet for building an RPM of the newer version, so I was required to piece together a solution on my own. Originally I built the package on a build virtual machine; however, I later chose to use Docker, as the package requires several dependencies and I did not want to break anything on the build server. This example uses Docker, but it should work on a standard CentOS system as well.

To begin, I obtained a spec file for the latest mongo-c-driver, for Fedora. At the time I used the FC34 mongo-c-driver-1.17.1-1 SRPM from Remi’s RPM repository and modified it to make it to work on CentOS 6 and 7. All credit goes to Remi Collet; I merely adapted this spec file for my own needs. Expand the below to see the example spec file:

mongo-c-driver.spec
# remirepo spec file for mongo-c-driver
#
# Copyright (c) 2015-2020 Remi Collet
# License: CC-BY-SA
# http://creativecommons.org/licenses/by-sa/4.0/
#
%global gh_owner     mongodb
%global gh_project   mongo-c-driver
%global libname      libmongoc
%global libver       1.0
%global up_version   1.17.4
#global up_prever    rc0
# disabled as require a MongoDB server
%bcond_with          tests

Name:      mongo-c-driver
Summary:   Client library written in C for MongoDB
Version:   %{up_version}%{?up_prever:~%{up_prever}}
Release:   1%{?dist}
# See THIRD_PARTY_NOTICES
License:   ASL 2.0 and ISC and MIT and zlib
URL:       https://github.com/%{gh_owner}/%{gh_project}

Source0:   https://github.com/%{gh_owner}/%{gh_project}/releases/download/%{up_version}%{?up_prever:-%{up_prever}}/%{gh_project}-%{up_version}%{?up_prever:-%{up_prever}}.tar.gz

BuildRequires: cmake3
BuildRequires: gcc
# pkg-config may pull compat-openssl10
BuildRequires: openssl-devel
%if %{with tests}
BuildRequires: mongodb-server
BuildRequires: openssl
%endif
# From man pages

Requires:   %{name}-libs%{?_isa} = %{version}-%{release}
Requires:   libmongocrypt
# Sub package removed
Obsoletes:  %{name}-tools         < 1.3.0
Provides:   %{name}-tools         = %{version}
Provides:   %{name}-tools%{?_isa} = %{version}

%description
%{name} is a client library written in C for MongoDB.

%package libs
Summary:    Shared libraries for %{name}

%description libs
This package contains the shared libraries for %{name}.

%package devel
Summary:    Header files and development libraries for %{name}
Requires:   %{name}%{?_isa} = %{version}-%{release}
Requires:   pkgconfig
Requires:   pkgconfig(libzstd)
Requires:   libmongocrypt

%description devel
This package contains the header files and development libraries
for %{name}.

Documentation: http://mongoc.org/libmongoc/%{version}/

%package -n libbson
Summary:    Building, parsing, and iterating BSON documents
# Modified (with bson allocator and some warning fixes and huge indentation
# refactoring) jsonsl is bundled .
# jsonsl upstream likes copylib approach and does not plan a release
# .
Provides:   bundled(jsonsl)

%description -n libbson
This is a library providing useful routines related to building, parsing,
and iterating BSON documents .

%package -n libbson-devel
Summary:    Development files for %{name}
Requires:   libbson%{?_isa} = %{version}-%{release}
Requires:   pkgconfig

%description -n libbson-devel
This package contains libraries and header files needed for developing
applications that use %{name}.

Documentation: http://mongoc.org/libbson/%{version}/

%prep
%setup -q -n %{gh_project}-%{up_version}%{?up_prever:-%{up_prever}}

%build
%cmake3 \
    -DENABLE_BSON:STRING=ON \
    -DENABLE_MONGOC:BOOL=ON \
    -DENABLE_SHM_COUNTERS:BOOL=ON \
    -DENABLE_SSL:STRING=OPENSSL \
    -DENABLE_SASL:STRING=CYRUS \
    -DENABLE_MONGODB_AWS_AUTH:STRING=ON \
    -DENABLE_ICU:STRING=ON \
    -DENABLE_AUTOMATIC_INIT_AND_CLEANUP:BOOL=OFF \
    -DENABLE_CRYPTO_SYSTEM_PROFILE:BOOL=ON \
    -DENABLE_MAN_PAGES:BOOL=ON \
    -DENABLE_STATIC:STRING=OFF \
%if %{with tests}
    -DENABLE_TESTS:BOOL=ON \
%else
    -DENABLE_TESTS:BOOL=OFF \
%endif
    -DENABLE_EXAMPLES:BOOL=OFF \
    -DENABLE_UNINSTALL:BOOL=OFF \
    -DENABLE_CLIENT_SIDE_ENCRYPTION:BOOL=ON \
    -S .

%if 0%{?cmake_build:1}
%cmake_build
%else
make %{?_smp_mflags}
%endif

%install
%if 0%{?cmake_install:1}
%cmake_install
%else
make install DESTDIR=%{buildroot}
%endif

: Static library
rm -f  %{buildroot}%{_libdir}/*.a
rm -rf %{buildroot}%{_libdir}/cmake/*static*
rm -rf %{buildroot}%{_libdir}/pkgconfig/*static*
: Documentation
rm -rf %{buildroot}%{_datadir}/%{name}

%check
ret=0

%if %{with tests}
: Run a server
mkdir dbtest
mongod \
  --journal \
  --ipv6 \
  --unixSocketPrefix /tmp \
  --logpath     $PWD/server.log \
  --pidfilepath $PWD/server.pid \
  --dbpath      $PWD/dbtest \
  --fork

: Run the test suite
export MONGOC_TEST_OFFLINE=on
export MONGOC_TEST_SKIP_MOCK=on
#export MONGOC_TEST_SKIP_SLOW=on

make check || ret=1

: Cleanup
[ -s server.pid ] && kill $(cat server.pid)
%endif

if grep -r static %{buildroot}%{_libdir}/cmake; then
  : cmake configuration file contain reference to static library
  ret=1
fi
exit $ret

%files
%{_bindir}/mongoc-stat

%files libs
%{!?_licensedir:%global license %%doc}
%license COPYING
%license THIRD_PARTY_NOTICES
%{_libdir}/%{libname}-%{libver}.so.*

%files devel
%doc src/%{libname}/examples
%doc NEWS
%{_includedir}/%{libname}-%{libver}
%{_libdir}/%{libname}-%{libver}.so
%{_libdir}/pkgconfig/%{libname}-*.pc
%{_libdir}/cmake/%{libname}-%{libver}
%{_libdir}/cmake/mongoc-%{libver}
%{_mandir}/man3/mongoc*

%files -n libbson
%license COPYING
%license THIRD_PARTY_NOTICES
%{_libdir}/libbson*.so.*

%files -n libbson-devel
%doc src/libbson/examples
%doc src/libbson/NEWS
%{_includedir}/libbson-%{libver}
%{_libdir}/libbson*.so
%{_libdir}/cmake/libbson-%{libver}
%{_libdir}/cmake/bson-%{libver}
%{_libdir}/pkgconfig/libbson-*.pc
%{_mandir}/man3/bson*
  

I placed this spec file in a work directory, then downloaded the mongo-c-driver tarball from https://github.com/mongodb/mongo-c-driver/releases into the same work directory. I also created two Yum repo files for installing some of the dependencies for the build. These were libmongocrypt and MongoDB (I chose to install version 4.0):

[libmongocrypt]
name=libmongocrypt repository
baseurl=https://libmongocrypt.s3.amazonaws.com/yum/redhat/$releasever/libmongocrypt/1.0/x86_64
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/libmongocrypt.asc
[mongodb-org-4.0]
name=MongoDB Repository
baseurl=https://repo.mongodb.org/yum/redhat/$releasever/mongodb-org/4.0/x86_64/
gpgcheck=1
enabled=1
gpgkey=https://www.mongodb.org/static/pgp/server-4.0.asc

Next, I created a Dockerfile in the work directory that installs the required dependencies and builds the image.

FROM centos:7
MAINTAINER Matt Ridpath matt@example.com
COPY libmongocrypt.repo /etc/yum.repos.d
COPY mongodb.repo /etc/yum.repos.d
RUN yum install -y epel-release
RUN yum install -y rpm-build icu libicu-devel python-sphinx python2-sphinx snappy cmake3 libzstd-devel libmongocrypt mongodb-org-server gcc openssl-devel cyrus-sasl-devel
WORKDIR /root
RUN mkdir -p rpmbuild/{BUILD,RPMS,SOURCES,SPECS,SRPMS}
COPY mongo-c-driver-*.tar.gz rpmbuild/SOURCES
COPY mongo-c-driver.spec rpmbuild/SPECS

Now the container image can be built:

sudo docker build --pull -t="matt/mongo-c-driver" .

Next, I created a directory for the container to mount as a pass-through volume, so that it has a location to copy the finished RPMs into. I chose to create an “artifacts” directory within my work directory, as this task would later be turned into a Jenkins job. You can chose another location, however. The option follows the format of -v <local_dir>:<container_dir>. Once the directory had been created, I ran the container to build the RPMs:

sudo docker run --rm -v $HOME/mongo-c-driver/artifacts:/artifacts matt/mongo-c-driver /bin/bash -c "cd rpmbuild/SPECS && rpmbuild -ba mongo-c-driver.spec && cp ../RPMS/x86_64/*.rpm /artifacts"

If the RPM builds successfully, the RPMs should be dropped into the specified local directory in the -v option and made available for installation.

matt@docker:~$ ls mongo-c-driver/artifacts/
libbson-1.17.4-1.el7.x86_64.rpm
libbson-devel-1.17.4-1.el7.x86_64.rpm
mongo-c-driver-1.17.4-1.el7.x86_64.rpm
mongo-c-driver-debuginfo-1.17.4-1.el7.x86_64.rpm
mongo-c-driver-devel-1.17.4-1.el7.x86_64.rpm
mongo-c-driver-libs-1.17.4-1.el7.x86_64.rpm

In a future post, I will show how I turned this task into a Jenkins job, so that one can build these packages regularly as new versions are released.

Finally, a disclaimer: I’m not an expert on Docker or building RPMs. Someone else more than likely has a better solution for achieving this end result. Rather, I would merely like to share how I arrived at a solution for building these packages and hope it will save someone else the trial and error I went through.

Credits:

1) Remi Collet for providing the spec file to modify for this task: https://rpms.remirepo.net/.
2) mongo-c-driver contributors and authors for providing the source tarball: https://github.com/mongodb/mongo-c-driver.
3) This guide for providing an example of how to build RPMs with Docker: http://saule1508.github.io/build-rpm-with-docker/.