INSTALL: List all the known direct dependencies and how to install them

Add a new documentation file with a full list of dependencies, stating
which of them are optional, how to install each of them, and which
versions have been tested.  Refer to this from README.

Closes #1.

2 files changed, 61 insertions, 0 deletions

diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..cf604eb
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,56 @@
+# Installing Lorry Controller
+
+## Dependencies
+
+Required:
+
+* **Python 3**: Tested with versions 3.6 and 3.8.
+
+* **Git**: Tested with versions 2.11 and 2.27.
+
+* **Lorry**: Also note the dependencies in its README.
+
+* **Bottle**: Can be installed from PyPI, or as the `python3-bottle`
+  package in Debian.  Tested with version 0.12.18.
+
+* **cliapp**: Can be installed as the `python3-cliapp` package in
+  Debian, or with:
+
+        pip3 install https://gitlab.com/trovekube/cliapp/-/archive/cliapp-1.20180812.1/cliapp-cliapp-1.20180812.1.tar.gz
+
+  or from the source at <https://liw.fi/cliapp/>.  Tested with version
+  1.20180812.1.
+
+* **PyYAML**: Can be installed from PyPI, or as the `python3-yaml`
+  package in Debian.  Tested with version 5.3.1.
+
+* **yoyo-migrations**: Can be installed from PyPI.  Tested with
+  version 7.0.2.
+
+Optional:
+
+* **curl**: Needed if you want to run the test suite.  Can be
+  installed as a distribution package.  Tested with versions 7.52.1
+  and 7.70.0.
+
+* **flup**: Needed if you want to run the web application as a FastCGI
+  server.  Can be installed from PyPI.  Tested with version 1.0.3, and
+  earlier versions won't run on Python 3.
+
+* **OpenSSH**: The OpenSSH client is needed if you want to use any
+  Downstream Host other than the local filesystem.  Tested with
+  versions 7.4p1 and 8.2p1.
+
+* **python-gitlab**: Needed if you want to use GitLab as a Downstream
+  or Upstream Host.  Can be installed from PyPI or as the
+  `python3-gitlab` package in Debian 10 onward.  Tested with version
+  1.15.0.
+
+* **Requests**: Needed if you want to use Gitano or GitLab as the
+  Downstream Host.  Can be installed from PyPI or as the
+  `python3-requests` package in Debian.  Tested with version 2.23.0.
+
+* **yarn**: Needed if you want to run the test suite.  Can be
+  installed as the `cmdtest` package in Debian, or from the source at
+  <https://liw.fi/cmdtest/>.  Tested with version 0.27-1 and with
+  commit `cdfe14e45134` on the master branch.
diff --git a/README b/README
index 34a1d1f..f2afb80 100644
--- a/README
+++ b/README
@@ -22,6 +22,11 @@ interface, and an HTTP API for reporting and controlling its state.
 This README file documents the LC configuration file and general use.
 For the architecture of LC and the HTTP API, see the `ARCH` file.
 
+Installation
+------------
+
+See the INSTALL file.
+
 Lorry Controller configuration: overview
 ------------------------------