Add simple script for running gitian-build

This shell script creates a docker image for running the gitian-build.py
script, to avoid version incompatibilities. The builds may be signed
automatically after manually reviewing the build hashes.

Only docker.io and apt-cacher-ng are required to be installed on the
host. The MacOSX SDK should also be present in this directory if Mac
builds are desired. A container named "gitrun" is used to launch
the builds, and all output will reside in this container as well.

1 files changed, 85 insertions, 0 deletions

diff --git a/contrib/gitian/DOCKRUN.md b/contrib/gitian/DOCKRUN.md
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+Quick Gitian building with docker
+=================================
+
+*Setup instructions for a Gitian build of Monero using Docker.*
+
+Gitian supports other container mechanisms too but if you have a Debian or
+Ubuntu-based host the steps can be greatly simplified.
+
+Preparing the Gitian builder host
+---------------------------------
+
+The procedure here will create a docker container for build preparation, as well as
+for actually running the builds. The only items you must install on your own host
+are docker and apt-cacher-ng. With docker installed, you should also give yourself
+permission to use docker by adding yourself to the docker group.
+
+```bash
+sudo apt-get install docker.io apt-cacher-ng
+sudo usermod -aG docker $USER
+su $USER
+```
+
+The final `su` command is needed to start a new shell with your new group membership,
+since the `usermod` command doesn't affect any existing sessions.
+
+If you want Mac binaries included in your build, you need to obtain the MacOS SDK:
+
+```bash
+curl -O https://bitcoincore.org/depends-sources/sdks/MacOSX10.11.sdk.tar.gz
+```
+
+Other User Preparation
+----------------------
+
+The final step will be to `gpg` sign the results of your build and upload them to GitHub.
+Before you can do that, you'll need
+* a GitHub account.
+If your GitHub account name is different from your local account name, you must
+set your GitHub account name for the script to use:
+
+```bash
+export GH_USER=<github account name>
+```
+
+* PGP keys - if you don't have one already, you can use `gpg --quick-gen-key` to generate it.
+* a fork of the [gitian.sigs](https://github.com/monero-project/gitian.sigs/) repo on your GitHub account.
+Please follow the directions there for uploading your key first.
+
+**Note:** Please ensure your gpg public key is available to check signatures by adding it to the [gitian.sigs/gitian-pubkeys/](https://github.com/monero-project/gitian.sigs/tree/master/gitian-pubkeys) directory in a pull request.
+
+
+Building the Binaries
+---------------------
+
+The dockrun.sh script will do everything to build the binaries. Just specify the
+version to build as its only argument, e.g.
+
+```bash
+./dockrun.sh v0.17.2.3
+```
+
+The build should run to completion with no errors, and will display the SHA256 checksums
+of the resulting binaries. You'll be prompted to check if the sums look good, and if so
+then the results will be signed, and the signatures will be pushed to GitHub.
+
+You can also look in the [gitian.sigs](https://github.com/monero-project/gitian.sigs/) repo and / or [getmonero.org release checksums](https://web.getmonero.org/downloads/hashes.txt) to see if others got the same checksum for the same version tag.  If there is ever a mismatch -- **STOP! Something is wrong**.  Contact others on IRC / GitHub to figure out what is going on.
+
+
+Other Options
+-------------
+
+This script just runs the [gitian-build.py](gitian-build.py) inside a container named `gitrun`.
+You can set other options for that script by setting the OPT variable when running `dockrun.sh`
+e.g.
+
+```bash
+OPT="-j 8" ./dockrun.sh v0.17.2.3
+```
+
+You can also examine the build and install logs by running a shell in the container, e.g.
+
+```bash
+docker exec -it gitrun /bin/bash
+more builder/var/install-linux.log
+```