Add a simple example.

Author: carlosalberto

examples/simple.py

@@ -0,0 +1,51 @@
+import os
+from sqlalchemy import MetaData, Table, Integer, String, Column, create_engine
+from sqlalchemy import select
+from sqlalchemy.schema import CreateTable
+
+import lightstep
+import sqlalchemy_opentracing
+
+DB_LOCATION = '/tmp/simple.db'
+
+tracer = lightstep.Tracer(
+    component_name='sqlalchemy-simple',
+    access_token='{your_lightstep_token}'
+)
+
+
+if __name__ == '__main__':
+    os.remove(DB_LOCATION) # cleanup
+
+    engine = create_engine('sqlite:///%s' % DB_LOCATION)
+    conn = engine.connect()
+
+    sqlalchemy_opentracing.init_tracing(tracer)
+    sqlalchemy_opentracing.register_connectable(engine)
+
+    span = tracer.start_span('create sample')
+
+    # 1. Create a table
+    metadata = MetaData()
+    users = Table('users', metadata,
+        Column('id', Integer, primary_key=True),
+        Column('name', String),
+    )
+    span = tracer.start_span('create sample')
+    creat = CreateTable(users)
+    sqlalchemy_opentracing.set_parent_span(creat, span)
+    conn.execute(creat)
+
+    # 2. Insert a single value.
+    ins = users.insert().values(name='John Doe', id=1)
+    sqlalchemy_opentracing.set_parent_span(ins, span)
+    conn.execute(ins)
+
+    # 3. Select the new value.
+    sel = select([users])
+    sqlalchemy_opentracing.set_parent_span(sel, span)
+    print conn.execute(sel).fetchone()
+
+    span.finish()
+    tracer.flush()
+