Enable gh-pages style static site deployment. (#97)

* Enable gh-pages style static site deployment.

As per #42 this PR allows the user to do static site deployments using
Piku which work very similarly to gh-pages. In the Procfile the user
defines a worker called 'static' with the path to the root of the files
to be served. An example app can be found here:
https://github.com/chr15m/piku-static-site

* Documentation.

README.md

@@ -22,6 +22,7 @@ The tiniest Heroku/CloudFoundry-like PaaS you've ever seen.
 * You can optionally also specify a `release` worker which is run once when the app is deployed.
 * You can then remotely change application settings (`config:set`) or scale up/down worker processes (`ps:scale`).
 * You can also bake application settings into a file called [`ENV` which is documented here](./docs/ENV.md).
+* A `static` worker type, with the root path as the argument, can be used to deploy a gh-pages style static site.
 
 ## Install
 

docs/DESIGN.md

@@ -20,7 +20,8 @@ An app is simply a `git` repository with some additional files on the top level,
 
 * `wsgi` workers, in the format `dotted.module:entry_point` (Python-only)
 * `web` workers, which can be anything that honors the `PORT` environment variable
-* `worker` prcesses, which are standalone workers and can have arbitrary names
+* `static` workers, which simply mount the first argument as the root static path
+* `worker` processes, which are standalone workers and can have arbitrary names
 
 So a Python application could have a `Procfile` like such:
 

piku.py

@@ -123,6 +123,10 @@ NGINX_COMMON_FRAGMENT = """
 
   $INTERNAL_NGINX_BLOCK_GIT
 
+  $INTERNAL_NGINX_PORTMAP
+"""
+
+NGINX_PORTMAP_FRAGMENT = """
   location    / {
     $INTERNAL_NGINX_UWSGI_SETTINGS
     proxy_http_version 1.1;
@@ -134,7 +138,7 @@ NGINX_COMMON_FRAGMENT = """
     proxy_set_header X-Forwarded-Port $server_port;
     proxy_set_header X-Request-Start $msec;
     $NGINX_ACL
- }
+  }
 """
 
 NGINX_ACME_FIRSTRUN_TEMPLATE = """
@@ -338,6 +342,9 @@ def do_deploy(app, deltas={}, newrev=None):
             elif (exists(join(app_path, 'Godeps')) or len(glob(join(app_path,'*.go')))) and check_requirements(['go']):
                 echo("-----> Go app detected.", fg='green')
                 settings.update(deploy_go(app, deltas))
+            elif 'static' in workers:
+                echo("-----> Static app detected.", fg='green')
+                settings.update(deploy_identity(app, deltas))
             else:
                 echo("-----> Could not detect runtime!", fg='red')
             # TODO: detect other runtimes
@@ -532,6 +539,11 @@ def deploy_python(app, deltas={}):
         call('pip install -r {}'.format(requirements), cwd=virtualenv_path, shell=True)
     return spawn_app(app, deltas)
 
+def deploy_identity(app, deltas={}):
+    env_path = join(ENV_ROOT, app)
+    if not exists(env_path):
+        makedirs(env_path)
+    return spawn_app(app, deltas)
  
 def spawn_app(app, deltas={}):
     """Create all workers for an app"""
@@ -586,7 +598,7 @@ def spawn_app(app, deltas={}):
     if exists(settings):
         env.update(parse_settings(settings, env))
 
-    if 'web' in workers or 'wsgi' in workers or 'jwsgi' in workers:
+    if 'web' in workers or 'wsgi' in workers or 'jwsgi' in workers or 'static' in workers:
         # Pick a port if none defined
         if 'PORT' not in env:
             env['PORT'] = str(get_free_port())
@@ -678,9 +690,13 @@ def spawn_app(app, deltas={}):
             env['INTERNAL_NGINX_BLOCK_GIT'] = "" if env.get('NGINX_ALLOW_GIT_FOLDERS') else "location ~ /\.git { deny all; }"
 
             env['INTERNAL_NGINX_STATIC_MAPPINGS'] = ''
-            
+
             # Get a mapping of /url:path1,/url2:path2
             static_paths = env.get('NGINX_STATIC_PATHS','')
+            # prepend static worker path if present
+            if 'static' in workers:
+                stripped = workers['static'].strip("/").rstrip("/")
+                static_paths = "/:" + (stripped if stripped else ".") + "/" + ("," if static_paths else "") + static_paths
             if len(static_paths):
                 try:
                     items = static_paths.split(',')
@@ -694,6 +710,9 @@ def spawn_app(app, deltas={}):
                     env['INTERNAL_NGINX_STATIC_MAPPINGS'] = ''
 
             env['INTERNAL_NGINX_CUSTOM_CLAUSES'] = expandvars(open(join(app_path, env["NGINX_INCLUDE_FILE"])).read(), env) if env.get("NGINX_INCLUDE_FILE") else ""
+            env['INTERNAL_NGINX_PORTMAP'] = ""
+            if 'web' in workers or 'uwsgi' in workers or 'jwsgi' in workers:
+                env['INTERNAL_NGINX_PORTMAP'] = expandvars(NGINX_PORTMAP_FRAGMENT, env)
             env['INTERNAL_NGINX_COMMON'] = expandvars(NGINX_COMMON_FRAGMENT, env)
 
             echo("-----> nginx will map app '{}' to hostname '{}'".format(app, env['NGINX_SERVER_NAME']))
@@ -847,10 +866,12 @@ def spawn_worker(app, kind, command, env, ordinal=1):
     elif kind == 'web':
         echo("-----> nginx will talk to the 'web' process via {BIND_ADDRESS:s}:{PORT:s}".format(**env), fg='yellow')
         settings.append(('attach-daemon', command))
+    elif kind == 'static':
+        echo("-----> nginx serving static files only".format(**env), fg='yellow')
     else:
         settings.append(('attach-daemon', command))
         
-    if kind in ['wsgi','web']:
+    if kind in ['wsgi', 'web']:
         settings.append(('log-format','%%(addr) - %%(user) [%%(ltime)] "%%(method) %%(uri) %%(proto)" %%(status) %%(size) "%%(referer)" "%%(uagent)" %%(msecs)ms'))
         
     # remove unnecessary variables from the env in nginx.ini
@@ -864,12 +885,13 @@ def spawn_worker(app, kind, command, env, ordinal=1):
     for k, v in env.items():
         settings.append(('env', '{k:s}={v}'.format(**locals())))
 
-    with open(available, 'w') as h:
-        h.write('[uwsgi]\n')
-        for k, v in settings:
-            h.write("{k:s} = {v}\n".format(**locals()))
-    
-    copyfile(available, enabled)
+    if kind != 'static':
+        with open(available, 'w') as h:
+            h.write('[uwsgi]\n')
+            for k, v in settings:
+                h.write("{k:s} = {v}\n".format(**locals()))
+
+        copyfile(available, enabled)
 
 def do_restart(app):
     config = glob(join(UWSGI_ENABLED, '{}*.ini'.format(app)))