PyRal 获取附件

Question

我有一个相当简单的用例，但我不理解收到的错误消息。

我正在使用 requests 和 pyral 模块，pyral (http://pyral.readthedocs.io/en/latest/interface.html#) 实际上只是 Rally 的 Restful api 的包装器。我的目标是从 Rally（CA 产品）UserStory 中获取文件（附件）并将其存储到本地文件系统中。

对于上下文，这是我的环境设置（验证 Rally 并创建一个对象）。我显然已经删除了身份验证信息。

from pyral import Rally, rallyWorkset

options = [arg for arg in sys.argv[1:] if arg.startswith('--')]
args = [arg for arg in sys.argv[1:] if arg not in options]
server, user, password, apikey, workspace, project = rallyWorkset(options)
rally = Rally(server='rally1.rallydev.com', 
user='**********', password='***********', 
          apikey="**************",
          workspace='**************', project='**************',
          server_ping=False)

之后，我只获得了一个用户故事的响应对象（请参阅 US845 的查询），我这样做只是为了简化问题。

r = rally.get('UserStory', fetch = True, projectScopeDown=True, query = 'FormattedID = US845')

然后我使用内置迭代器从 RallyRESTResponse 对象中获取用户故事。

us = r.next()

从那里感觉我应该能够轻松地使用接受工件（我们）和文件名（附件名称）的 getAttachment() 方法。我可以使用 getAttachmentNames(us) 返回附件名称列表。当我尝试类似的事情时，问题就出现了

attachment_names = rally.getAttachmentNames(us) #get attachments for this UserStory
attachment_file = rally.getAttachment(us, attachment_names[0]) #Try to get the first attachment 

返回这样的错误

Traceback (most recent call last):

File "<ipython-input-81-a4a342a59c5a>", line 1, in <module>
attachment_file = rally.getAttachment(us, attachment_names[0])

File "C:\Miniconda3\lib\site-packages\pyral\restapi.py", line 1700, in getAttachment
att.Content = base64.decodebytes(att_content.Content)  # maybe further txfm to Unicode ?

File "C:\Miniconda3\lib\base64.py", line 552, in decodebytes
_input_type_check(s)

File "C:\Miniconda3\lib\base64.py", line 520, in _input_type_check
raise TypeError(msg) from err

TypeError: expected bytes-like object, not str

如果我尝试使用，我会收到类似的错误

test_obj = rally.getAttachments(us)

返回如下错误：

Traceback (most recent call last):

File "<ipython-input-82-06a8cd525177>", line 1, in <module>
rally.getAttachments(us)

File "C:\Miniconda3\lib\site-packages\pyral\restapi.py", line 1721, in getAttachments
attachments = [self.getAttachment(artifact, attachment_name) for attachment_name in attachment_names]

File "C:\Miniconda3\lib\site-packages\pyral\restapi.py", line 1721, in <listcomp>
attachments = [self.getAttachment(artifact, attachment_name) for attachment_name in attachment_names]

File "C:\Miniconda3\lib\site-packages\pyral\restapi.py", line 1700, in getAttachment
att.Content = base64.decodebytes(att_content.Content)  # maybe further txfm to Unicode ?

File "C:\Miniconda3\lib\base64.py", line 552, in decodebytes
_input_type_check(s)

File "C:\Miniconda3\lib\base64.py", line 520, in _input_type_check
raise TypeError(msg) from err

TypeError: expected bytes-like object, not str

似乎我从根本上误解了这种方法所需的参数？有没有人能够成功地做到这一点？对于它的价值，我使用 addAttachment() 方法和上面类似的工作流程没有任何问题。我尝试使用 bytes() 方法将文件名（字符串）转换为 utf-8，但这没有帮助。

我也在 pyral 源代码中查看了这个示例，但在尝试执行该示例时收到完全相同的错误。

https://github.com/klehman-rally/pyral/blob/master/examples/get_attachments.py

Answer 1

看起来像 restapi.py 脚本中的问题 - base64 库中没有 decodebytes 方法：

att.Content = base64.decodebytes(att_content.Content)

所有可用的方法都在以下位置进行了描述： RFC 3548: Base16, Base32, Base64 Data Encodings 因此，解决方法是在restapi.py 中用base64.b64decode 替换decodebytes。至少，它对我有用。

例如Mac OS X 上的位置：

/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pyral/restapi.py

Answer 2

我已使用以下代码获取所有附件，因为 getAttachments 未按预期工作。它将在当前目录中创建一个同名的文件。

import sys
import string
import base64
from pyral import rallyWorkset, Rally,RallyRESTResponse

rally = Rally(server, user=USER_NAME, password=PASSWORD, workspace=workspace, project=project)
criterion = 'FormattedID = US57844'
response = rally.get('HierarchicalRequirement',  query=criterion, order="FormattedID",pagesize=200, limit=400, projectScopeDown=True)

artifact = response.next()
context, augments = rally.contextHelper.identifyContext()
for att in artifact.Attachments:
    resp = rally._getResourceByOID(context, 'AttachmentContent', att.Content.oid, project=None)
    if resp.status_code not in [200, 201, 202]:
        break
    res = RallyRESTResponse(rally.session, context, "AttachmentContent.x", resp, "full", 1)
    if res.errors or res.resultCount != 1:
        print("breaking the for loop")
    att_content = res.next()
    cont = att_content.Content
    x = base64.b64decode(cont)
    output = open(att.Name, 'wb') 
    output.write(x)