improve readme

Author: samuelcolvin

README.rst

@@ -10,7 +10,7 @@ PDF generation in python using
 Wkhtmltopdf binaries are precompiled and included in the package making
 pydf easier to use, in particular this means pydf works on heroku.
 
-Currently using **wkhtmltopdf 0.12.4 (with patched qt)**.
+Currently using **wkhtmltopdf 0.12.4 (with patched qt)**, requires **Python 3.6+**.
 
 Install
 -------
@@ -19,7 +19,7 @@ Install
 
     pip install python-pdf
 
-(pydf was taken, but I guess python-pdf is a clearer name anyway.)
+For python 2 use ``pip install python-pdf==0.30.0``.
 
 Basic Usage
 -----------
@@ -28,11 +28,7 @@ Basic Usage
 
     import pydf
     pdf = pydf.generate_pdf('<h1>this is html</h1>')
-    with open('test_doc.pdf', 'w') as f:
-        f.write(pdf)
-
-    pdf = pydf.generate_pdf('www.google.com')
-    with open('google.pdf', 'w') as f:
+    with open('test_doc.pdf', 'wb') as f:
         f.write(pdf)
 
 Async Usage
@@ -44,38 +40,28 @@ at the same time. Thus the time taken to spin up processes doesn't slow you down
 
 .. code:: python
 
-   async def go_async():
-       count = 20
-       apydf = AsyncPydf(max_processes=20)
-
-       async def gen(i_):
-           pdf = await apydf.generate_pdf(
-               html,
-               title='Benchmark',
-               author='Samuel Colvin',
-               subject='Mock Invoice',
-               page_size='A4',
-               zoom='1.25',
-               margin_left='8mm',
-               margin_right='8mm',
-           )
-           print(f'{i_:03}: {len(pdf)}')
-           file = OUT_DIR / f'output_{i_:03}.pdf'
-           file.write_bytes(pdf)
-
-       coros = []
-       for i in range(count):
-           coros.append(gen(i))
-       await asyncio.gather(*coros)
-       return count
-
-   loop = asyncio.get_event_loop()
-   loop.run_until_complete(go_async())
+    from pathlib import Path
+    from pydf import AsyncPydf
+
+    async def generate_async():
+        apydf = AsyncPydf()
+
+        async def gen(i):
+            pdf_content = await apydf.generate_pdf('<h1>this is html</h1>')
+            Path(f'output_{i:03}.pdf').write_bytes(pdf_content)
+
+        coros = [gen(i) for i in range(50)]
+        await asyncio.gather(*coros)
+
+    loop = asyncio.get_event_loop()
+    loop.run_until_complete(generate_async())
 
 
 See `benchmarks/run.py <https://github.com/tutorcruncher/pydf/blob/master/benchmark/run.py>`__
 for a full example.
 
+Locally generating an entire invoice goes from 0.372s/pdf to 0.035s/pdf with the async model.
+
 API
 ---
 
@@ -90,8 +76,7 @@ For details on extra arguments see the output of get\_help() and
 get\_extended\_help()
 
 All arguments whether specified or caught with extra\_kwargs are
-converted to command line args with
-``'--' + original_name.replace('_', '-')``.
+converted to command line args with ``'--' + original_name.replace('_', '-')``.
 
 Arguments which are True are passed with no value eg. just --quiet,
 False and None arguments are missed, everything else is passed with

benchmark/run.py

@@ -40,8 +40,7 @@ def go_sync():
 print(f'sync, time taken per pdf: {time_taken:0.3f}s')
 
 async def go_async():
-    count = 20
-    apydf = AsyncPydf(max_processes=20)
+    apydf = AsyncPydf()
 
     async def gen(i_):
         pdf = await apydf.generate_pdf(
@@ -55,12 +54,11 @@ async def gen(i_):
             margin_right='8mm',
         )
         print(f'{i_:03}: {len(pdf)}')
-        file = OUT_DIR / f'output_{i_:03}.pdf'
-        file.write_bytes(pdf)
+        f = OUT_DIR / f'output_{i_:03}.pdf'
+        f.write_bytes(pdf)
 
-    coros = []
-    for i in range(count):
-        coros.append(gen(i))
+    count = 20
+    coros = map(gen, range(count))
     await asyncio.gather(*coros)
     return count