(FM-7109) Add ability to dynamically specify environment

CHANGELOG.md

@@ -12,6 +12,13 @@ Changelog
   * `facility`
 * Extend interface with attributes:
    * `ipv6_redirects`
+* Added ability to specify environment at run time
+
+Example:
+```ruby
+env = { host: '192.168.1.1', port: nil, username: 'admin', password: 'admin123', cookie: nil }
+Cisco::Environment.add_env('default', env)
+```
 
 ### Changed
 

README.md

@@ -85,6 +85,14 @@ An example configuration file (illustrating each of the above scenarios) is prov
 
 *For security purposes, it is highly recommended that access to this file be restricted to only the owning user (`chmod 0600`).*
 
+Configuration may also be specified at runtime and can be used in the absence of configuration files or to override them.
+
+Example:
+```ruby
+env = { host: '192.168.1.1', port: nil, username: 'admin', password: 'admin123', cookie: nil }
+Cisco::Environment.add_env('default', env)
+```
+
 ## <a name="documentation">Documentation</a>
 
 ### Client
@@ -151,12 +159,18 @@ client2 = Cisco::Client.create('n9k')
 # Warning: Make sure to exclude devices using the 'no_proxy' environment variable
 # to ensure successful remote connections.
 
+# Add runtime configuration for remote device and connect
+env = { host: '192.168.1.1', port: nil, username: 'admin', password: 'admin123', cookie: nil }
+Cisco::Environment.add_env('remote', env)
+client3 = Cisco::Client.create('remote')
+
 # Use connections to get and set device state.
 client1.set(values: 'feature vtp')
 client1.set(values: 'vtp domain mycompany.com')
 puts client1.get(command: 'show vtp status | inc Domain')
 
 puts client2.get(command: 'show version')
+puts client3.get(command: 'show version')
 ```
 
 #### High-level Node API

ext/mkrf_conf.rb

@@ -37,7 +37,7 @@
   os == 'ios_xr' || deps << Gem::Dependency.new('net_http_unix',
                                                 '~> 0.2', '>= 0.2.1')
   # NX-OS doesn't need gRPC
-  os == 'nexus' || deps << Gem::Dependency.new('grpc', '~> 0.12')
+  os == 'nexus' || deps << Gem::Dependency.new('grpc', '~> 1.14.1')
 
   deps.each do |dep|
     installed = dep.matching_specs

lib/cisco_node_utils/environment.rb

@@ -1,6 +1,7 @@
+# August 2018
 # March 2016, Glenn F. Matthews
 #
-# Copyright (c) 2016 Cisco and/or its affiliates.
+# Copyright (c) 2016-2018 Cisco and/or its affiliates.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -90,6 +91,12 @@ def self.data_from_file(path)
       {}
     end
 
+    def self.add_env(env_name, env_hash)
+      fail ArgumentError, 'empty environment name' if env_name.empty?
+      fail TypeError, 'invalid environment hash' unless env_hash.is_a?(Hash)
+      @environments[env_name] = env_hash
+    end
+
     def self.strings_to_symbols(hash)
       Hash[hash.map { |k, v| [k.to_sym, v] }]
     end

spec/environment_spec.rb

@@ -70,6 +70,37 @@ class << Cisco::Environment
     end
   end
 
+  describe '.add_env' do
+    it 'rejects empty environment name' do
+      expect { described_class.add_env('', {}) }.to \
+        raise_error(ArgumentError, 'empty environment name')
+    end
+
+    it 'rejects incorrectly typed environment hash' do
+      expect { described_class.add_env('default', 'hash') }.to \
+        raise_error(TypeError, 'invalid environment hash')
+    end
+
+    context 'environment can be loaded by funcion' do
+      expected = {
+        host:     '192.168.1.1',
+        port:     nil,
+        username: 'admin',
+        password: 'admin',
+        cookie:   nil,
+      }
+      it 'can be loaded explicitly by name' do
+        described_class.add_env('test', expected)
+        expect(Cisco::Environment.environment('test')).to eq(expected)
+      end
+
+      it 'can be default' do
+        described_class.add_env('default', expected)
+        expect(Cisco::Environment.environment).to eq(expected)
+      end
+    end
+  end
+
   describe '.environments' do
     before(:each) do
       allow(Cisco::Environment).to receive(:data_from_file).and_return({})
@@ -162,6 +193,82 @@ class << Cisco::Environment
         },
       )
     end
+
+    it 'loaded file can be overridden by add_env' do
+      expect(Cisco::Environment).to receive(:data_from_file).with(
+        '/etc/cisco_node_utils.yaml').and_return(global_config)
+      expect(Cisco::Environment).to receive(:data_from_file).with(
+        '~/cisco_node_utils.yaml').and_return(user_config)
+      expect(Cisco::Environment.environments).to eq(
+        'default' => {
+          host:     '127.0.0.1', # global config
+          port:     57_799, # user overrides global
+          username: 'user', # user config
+          password: nil, # auto-populated with nil
+          cookie:   nil,
+        },
+        'global'  => { # global config
+          host:     nil,
+          port:     nil,
+          username: 'global',
+          password: 'global',
+          cookie:   nil,
+        },
+        'user'    => { # user config
+          host:     nil,
+          port:     nil,
+          username: 'user',
+          password: 'user',
+          cookie:   nil,
+        },
+      )
+      added_env = {
+        host:     '192.168.1.1',
+        port:     nil,
+        username: 'admin',
+        password: 'admin',
+        cookie:   nil,
+      }
+      overide_defult = {
+        host:     '192.168.2.2',
+        port:     nil,
+        username: 'overridden',
+        password: 'overridden',
+        cookie:   nil,
+      }
+      described_class.add_env('added', added_env)
+      described_class.add_env('default', overide_defult)
+      expect(Cisco::Environment.environments).to eq(
+        'added'   => { # added by method
+          host:     '192.168.1.1',
+          port:     nil,
+          username: 'admin',
+          password: 'admin',
+          cookie:   nil,
+        },
+        'default' => {
+          host:     '192.168.2.2', # method overrides files
+          port:     nil, # method overrides files
+          username: 'overridden', # method overrides files
+          password: 'overridden', # method overrides files
+          cookie:   nil, # auto-popuplated with nil
+        },
+        'global'  => { # global config
+          host:     nil,
+          port:     nil,
+          username: 'global',
+          password: 'global',
+          cookie:   nil,
+        },
+        'user'    => { # user config
+          host:     nil,
+          port:     nil,
+          username: 'user',
+          password: 'user',
+          cookie:   nil,
+        },
+      )
+    end
   end
 
   context '.environment' do