Improves documentation

pisa-btc/apps/cli/DEPENDENCIES.md

@@ -1,7 +1,78 @@
 # Dependencies
 
-The app has the following dependencies (which can be satisfied by using `pip install -r requirements.txt`):
+`pisa-cli` has both system-wide and Python dependencies. This document walks you trough how to satisfy them.
 
-#### Cryptography
-`cryptography`
+## System-wide dependencies
 
+`pisa-cli` has the following system-wide dependencies:
+
+- `python3`
+- `pip3`
+
+### Checking if the dependencies are already satisfied
+
+Most UNIX systems ship with `python3` already installed, whereas OSX systems tend to ship with `python2`. In order to check our python version we should run:
+
+	python --version
+
+For what we will get something like:
+
+	Python 2.X.X
+	
+Or
+	
+	Python 3.X.X
+	
+It is also likely that, if `python3` is installed in our system, the `python` alias is not set to it but instead to `python2`. In order to check so, we can run:
+
+	python3 --version
+
+If `python3` is installed but the `python` alias is not set to it, we should either set it, or use `python3` to run `pisa-cli`.
+
+Regarding `pip`, we can check what version is installed in our system (if any) by running:
+
+	pip --version
+
+For what we will get something like:
+
+	pip X.X.X from /usr/local/lib/python2.X/dist-packages/pip (python 2.X)
+	
+Or
+
+	pip X.X.X from /usr/local/lib/python3.X/dist-packages/pip (python 3.X)
+
+A similar thing to the `python` alias applies to the `pip` alias. We can check if pip3 is install by running:
+
+	pip3 --version
+	
+And, if it happens to be installed, change the alias to `pip3`, or use `pip3` instead of `pip`.
+
+
+### Installing the dependencies
+
+`python3` ca be downloaded from the [Python official website](https://www.python.org/downloads/) or installed using a package manager, depending on your distribution. Examples for both UNIX-like and OSX systems are provided.
+
+#### Ubuntu
+
+`python3` can be installed using `apt` as follows:
+
+	sudo apt-get update
+	sudo apt-get install python3
+	
+and for `pip3`:
+
+	sudo apt-get install python3-pip
+	
+#### OSX
+
+`python3` can be installed using `Homebriew` as follows:
+	
+	brew install python3
+
+`pip3` will be installed alongside `python3` in this case.
+
+## Python dependencies
+
+`pisa-cli` has the following dependencies (which can be satisfied by using `pip install -r requirements.txt`):
+
+- `cryptography`

pisa-btc/apps/cli/INSTALL.md

@@ -0,0 +1,20 @@
+# Install 
+
+`pisa-cli` has some dependencies that can be satisfied by following [DEPENDENCIES.md](DEPENDENCIES.md). If your system already satisfies the dependencies, you can skip that part.
+
+In order to run `pisa-cli`, you should set your `PYTHONPATH` env variable to include the folder that contains the `apps` folder. You can do so by running:
+
+	export PYTHONPATH=$PYTHONPATH:<absolute_path_to_apps>
+	
+For example, for user alice running a UNIX system and having `apps` in her home folder, she would run:
+	
+	export PYTHONPATH=$PYTHONPATH:/home/alice/
+	
+You should also include the command in your `.bash_rc` to avoid having to run it every time you open a new terminal. You can do it by running:
+
+	echo 'export PYTHONPATH=$PYTHONPATH:<absolute_path_to_apps>' >> ~/.bash_rc
+	
+Once the `PYTHONPATH` is set, you should be able to run `pisa-cli` straightaway. Try it by running:
+
+	cd <absolute_path_to_apps>/apps/cli
+	python pisa-cli.py -h

pisa-btc/apps/cli/README.md

@@ -1,8 +1,15 @@
 ## pisa-cli
 
-`pisa-cli` is a command line interface to interact with the PISA server. 
+`pisa-cli` is a command line interface to interact with the PISA server, written in Python3.
 
-#### Usage
+### Dependencies
+Refer to [DEPENCENCIES.md](DEPENCENCIES.md)
+
+### Installation
+
+Refer to [INSTALL.md](INSTALL.md)
+
+### Usage
 
 	python pisa-cli.py [global options] command [command options] [arguments]
 	
@@ -119,8 +126,8 @@ Run:
 Shows the list of commands or help about how to run a specific command.
 
 #### Usage
-	python pisa-cli help command
+	python pisa-cli help
 	
 or
 
-	python pisa-cli command -h
+	python pisa-cli help command

pisa-btc/apps/cli/pisa-cli.py

@@ -8,9 +8,9 @@ from sys import argv
 from getopt import getopt, GetoptError
 from hashlib import sha256
 from binascii import unhexlify
-from apps.cli.blob import Blob
 from requests import ConnectTimeout, ConnectionError
 from apps.cli import DEFAULT_PISA_API_SERVER, DEFAULT_PISA_API_PORT, CLIENT_LOG_FILE
+from apps.cli.blob import Blob
 from apps.cli.help import help_add_appointment, help_get_appointment
 
 
@@ -211,6 +211,8 @@ if __name__ == '__main__':
 
             else:
                 sys.exit("Unknown command. Use help to check the list of available commands.")
+        else:
+            sys.exit("No command provided. Use help to check the list of available commands.")
 
     except GetoptError as e:
         print(e)