pyAAWS for Product Advertising API

Python library of Amazon Associates Web Service を Product Advertising API に対応させました。電子署名とか・・・。追加点は新API仕様のとおりです。解説がめんどいので、diff 貼ります。

+import hashlib
+import hmac
+import base64

-Version = '2009-02-01'
+Version = '2009-03-31'

   def _get_url(self, kw):
-    url = 'http://%s/onca/xml?Service=%s&AWSAccessKeyId=%s&Version=%s&' % (
-      supported_locales[self.locale],
-      Service,
-      self.AWSAccessKeyId,
-      Version,
-    )
     if not kw:
       kw = {}
+    kw['Service'] = Service
+    kw['Version'] = Version
+    kw['AWSAccessKeyId'] = self.AccessKeyId
+    kw['Timestamp'] = datetime.datetime.utcnow().isoformat()
     if (not 'AssociateTag' in kw) or (not kw['AssociateTag'] and self.AssociateTag):
       kw['AssociateTag'] = self.AssociateTag
     if (not 'MerchantId' in kw) or (not kw['MerchantId'] and self.MerchantId):
       kw['MerchantId'] = self.MerchantId
     if (not 'Validate' in kw) or (not kw['Validate'] and Validate):
       kw['Validate'] = Validate
-    url += '&'.join(['%s=%s' % (k, urllib.quote(unicode(v))) \
-      for (k, v) in kw.items() if v])
-    return url
+    [kw.pop(k) for (k, v) in kw.items() if not v]
+    payload = urllib.urlencode(sorted(kw.items()))
+    urllib2.quote
+    strings = [
+      'GET',
+      supported_locales[self.locale],
+      end_point,
+      payload
+    ]
+    digest = hmac.new(
+      self.SecretAccessKey,
+      '\n'.join(strings),
+      hashlib.sha256
+    ).digest()
+    signature = base64.b64encode(digest)
+    return 'http://%(uri)s%(end_point)s?%(payload)s&Signature=%(signature)s' % {
+      'uri':supported_locales[self.locale],
+      'end_point':end_point,
+      'payload':payload,
+      'signature':signature,
+    }

詳細の diff は bitbucket （なんちゅうブログやｗ） へ。ノットリファクタリング。使い方が変わったところは、Secret Access Key が必須になったところぐらいです。

import awws
- api = Api('[取得した Access Key Id]')
+ api = Api('[取得した Access Key Id]', '[取得した Secret Access Key]')