write proxy config to installer and target /etc/environment

also emit a signal when proxy config is set

subiquity/controllers/proxy.py

@@ -16,6 +16,7 @@
 import logging
 
 from subiquitycore.controller import BaseController
+from subiquitycore import utils
 
 from subiquity.ui.views.proxy import ProxyView
 
@@ -42,4 +43,11 @@ class ProxyController(BaseController):
 
     def done(self, proxy):
         self.model.proxy = proxy
+        if proxy:
+            new_env_path = '/etc/environment'
+            if self.opts.dry_run:
+                new_env_path = '.subiquity' + new_env_path
+            with open(new_env_path, 'w') as fp:
+                fp.write(self.model.etc_environment_content())
+            self.signal.emit_signal('network-proxy-set')
         self.signal.emit_signal('next-screen')

subiquity/models/proxy.py

@@ -22,3 +22,16 @@ class ProxyModel(object):
 
     def __init__(self):
         self.proxy = ""
+
+    def etc_environment_content(self):
+        env_lines = []
+        with open("/etc/environment") as fp:
+            for line in fp:
+                if line.startswith('http_proxy=') or line.startswith('https_proxy='):
+                    continue
+                if not line.endswith('\n'):
+                    line += '\n'
+                env_lines.append(line)
+        env_lines.append("http_proxy={}\n".format(self.proxy))
+        env_lines.append("https_proxy={}\n".format(self.proxy))
+        return ''.join(env_lines)

subiquity/models/subiquity.py

@@ -142,6 +142,10 @@ class SubiquityModel:
                     'path': 'etc/default/keyboard',
                     'content': self.keyboard.setting.render(),
                     },
+                'etc_environment': {
+                    'path': 'etc/environment',
+                    'content': self.proxy.etc_environment_content(),
+                    },
                 },
             }