Dependencies
============

grpc has few external dependencies. If needed, they are present in the
third_party directory, if you have cloned the github repository recursively.
If you didn't clone recursively, you can still get them later by running the
following command:

$ git submodule --init update


grpc core currently depends on zlib and OpenSSL 1.0.2beta3, and also requires
libevent2 for the Linux port.

grpc++'s tests depends on protobuf 3.0.0, gtests and gflags.

OpenSSL
-------

Secure HTTP2 requires to have the TLS extension ALPN (see rfc 7301 and
http://http2.github.io/http2-spec/ section 3.3). Our HTTP2 implementation
relies on OpenSSL's implementation. OpenSSL 1.0.2beta3 is the first version
of OpenSSL that has ALPN support, and this explains our dependency on it.


Compiling
=========

Currently, you will need to manually install OpenSSL-1.0.2beta3 prior
attempting to compile grpc. To avoid clobbering any system OpenSSL, it is
preferable to install it in a separate directory. Running binaries however
will require the appropriate LD_LIBRARY_PATH variable set up, as shown later.

To compile OpenSSL 1.0.2beta3:

$ cd third_party/openssl
$ ./config --prefix=/usr/local/openssl-alpn --shared
$ make
$ sudo make install


After that step, you can compile grpc:

$ ssl=/usr/local/openssl-alpn
$ CPPFLAGS=-I$ssl/include LDFLAGS=-L$ssl/lib make

This will compile both grpc and grpc++.


Testing
=======

At the moment, C++ tests aren't fully available yet. If you want to run tests
on the C core of grpc, you can do the following:

$ CPPFLAGS=-I$ssl/include LDFLAGS=-L$ssl/lib make buildtests_c
$ LD_LIBRARY_PATH=$ssl/lib make test_c


Installing
==========

Once everything is compiled, you should be able to install grpc and grpc++
libraries and headers:

$ sudo make install