Changed tweets, added eca

demos/rolling_chart.py

@@ -0,0 +1,94 @@
+from eca import *
+
+import random
+
+# This function will be called to set up the HTTP server
+def add_request_handlers(httpd):
+    # use the library content from the template_static dir instead of our own
+    # this is a bit finicky, since execution now depends on a proper working directory.
+    httpd.add_content('/lib/', 'template_static/lib')
+    httpd.add_content('/style/', 'template_static/style')
+
+
+# binds the 'setup' function as the action for the 'init' event
+# the action will be called with the context and the event
+@event('init')
+def setup(ctx, e):
+    ctx.count = 0
+    ctx.samples = {
+        'sensor0': 0.0,
+        'sensor1': 0.0
+    }
+
+    fire('sample', {
+        'previous': 0.0,
+        'name': 'sensor0',
+        'failure-chance': 0.0,
+        'reboot-chance': 1.0,
+        'delay': 0.05
+    })
+
+    fire('sample', {
+        'previous': 0.0,
+        'name': 'sensor1',
+        'failure-chance': 0.05,
+        'reboot-chance': 0.1,
+        'delay': 0.05
+    })
+
+    fire('sample', {
+        'previous': None,
+        'name': 'sensor2',
+        'failure-chance': 0.2,
+        'reboot-chance': 0.8,
+        'delay': 0.1
+    })
+
+    fire('tick')
+
+
+# define a normal Python function
+def clip(lower, value, upper):
+    return max(lower, min(value, upper))
+
+@event('sample')
+@condition(lambda c,e: e.get('previous') is not None)
+def generate_sample(ctx, e):
+    sample = e.get('previous')
+    # failure chance off...
+    if e.get('failure-chance') > random.random():
+        sample = None
+        del ctx.samples[e.get('name')]
+    else:
+        # base sample on previous one
+        sample = clip(-100, e.get('previous') + random.uniform(+5.0, -5.0), 100)
+        ctx.samples[e.get('name')] = sample
+
+    # chain event
+    data = dict(e.data)
+    data.update({'previous': sample})
+    fire('sample', data, delay=e.get('delay'))
+
+@event('sample')
+@condition(lambda c,e: e.get('previous') is None)
+def try_reboot(ctx, e):
+    sample = e.get('previous')
+    if e.get('reboot-chance') > random.random():
+        sample = random.uniform(100,-100)
+        ctx.samples[e.get('name')] = sample
+
+    data = dict(e.data)
+    data.update({'previous': sample})
+    fire('sample', data, delay=e.get('delay'))
+
+
+@event('tick')
+def tick(ctx, e):
+    # emit to outside world
+    emit('sample',{
+        'action': 'add',
+        'values': ctx.samples
+    })
+    fire('tick', delay=0.05);
+
+