B
    ^ c:                 @   s   d Z dgZddlZddlZddlZedZedZG dd deZ	dd	 Z
d
d Zdd ZG dd dZG dd dZG dd dZG dd dZG dd dZdd Zdd Zdd Zdd Zdd  Zd!d" Zd#d$ Zd%d& ZdS )'a&  
Middleware to check for obedience to the WSGI specification.

Some of the things this checks:

* Signature of the application and start_response (including that
  keyword arguments are not used).

* Environment checks:

  - Environment is a dictionary (and not a subclass).

  - That all the required keys are in the environment: REQUEST_METHOD,
    SERVER_NAME, SERVER_PORT, wsgi.version, wsgi.input, wsgi.errors,
    wsgi.multithread, wsgi.multiprocess, wsgi.run_once

  - That HTTP_CONTENT_TYPE and HTTP_CONTENT_LENGTH are not in the
    environment (these headers should appear as CONTENT_LENGTH and
    CONTENT_TYPE).

  - Warns if QUERY_STRING is missing, as the cgi module acts
    unpredictably in that case.

  - That CGI-style variables (that don't contain a .) have
    (non-unicode) string values

  - That wsgi.version is a tuple

  - That wsgi.url_scheme is 'http' or 'https' (@@: is this too
    restrictive?)

  - Warns if the REQUEST_METHOD is not known (@@: probably too
    restrictive).

  - That SCRIPT_NAME and PATH_INFO are empty or start with /

  - That at least one of SCRIPT_NAME or PATH_INFO are set.

  - That CONTENT_LENGTH is a positive integer.

  - That SCRIPT_NAME is not '/' (it should be '', and PATH_INFO should
    be '/').

  - That wsgi.input has the methods read, readline, readlines, and
    __iter__

  - That wsgi.errors has the methods flush, write, writelines

* The status is a string, contains a space, starts with an integer,
  and that integer is in range (> 100).

* That the headers is a list (not a subclass, not another kind of
  sequence).

* That the items of the headers are tuples of strings.

* That there is no 'status' header (that is used in CGI, but not in
  WSGI).

* That the headers don't contain newlines or colons, end in _ or -, or
  contain characters codes below 037.

* That Content-Type is given if there is content (CGI often has a
  default content type, but WSGI does not).

* That no Content-Type is given when there is no content (@@: is this
  too restrictive?)

* That the exc_info argument to start_response is a tuple or None.

* That all calls to the writer are with strings, and no other methods
  on the writer are accessed.

* That wsgi.input is used properly:

  - .read() is called with zero or one argument

  - That it returns a string

  - That readline, readlines, and __iter__ return strings

  - That .close() is not called

  - No other methods are provided

* That wsgi.errors is used properly:

  - .write() and .writelines() is called with a string

  - That .close() is not called, and no other methods are provided.

* The response iterator:

  - That it is not a string (it should be a list of a single string; a
    string will work, but perform horribly).

  - That .__next__() returns a string

  - That the iterator is not iterated over until start_response has
    been called (that can signal either a server or application
    error).

  - That .close() is called (doesn't raise exception, only prints to
    sys.stderr, because we only know it isn't called when the object
    is garbage collected).
	validator    Nz^[a-zA-Z][a-zA-Z0-9\-_]*$z[\000-\037]c               @   s   e Zd ZdZdS )WSGIWarningz:
    Raised in response to WSGI-spec-related warnings
    N)__name__
__module____qualname____doc__ r   r   !lib/python3.7/wsgiref/validate.pyr   y   s   r   c             G   s   | st | d S )N)AssertionError)Zcondargsr   r   r	   assert_~   s    r   c             C   s(   t | tkr| S td|t| d S )Nz!{0} must be of type str (got {1}))typestrr
   formatrepr)valuetitler   r   r	   check_string_type   s    r   c                s    fdd}|S )a  
    When applied between a WSGI server and a WSGI application, this
    middleware will check for WSGI compliancy on a number of levels.
    This middleware does not modify the request or response in any
    way, but will raise an AssertionError if anything seems off
    (except for a failure to close the application iterator, which
    will be printed to stderr -- there's no way to raise an exception
    at that point).
    c                 s   t t| dkd t | d | \} t| g  fdd}t|d |d< t|d |d< ||}t |d k	oz|dkd	 t| t|S )
N   zTwo arguments requiredzNo keyword arguments allowedc                 s   t t| dkpt| dkd| f  t | d | d }| d }t| dkrV| d }nd }t| t| t|| t| d  t |  S )Nr      zInvalid number of arguments: %szNo keyword arguments allowedr      )r   lencheck_statuscheck_headerscheck_content_typecheck_exc_infoappendWriteWrapper)r   kwstatusheadersexc_info)start_responsestart_response_startedr   r	   start_response_wrapper   s    


z;validator.<locals>.lint_app.<locals>.start_response_wrapperz
wsgi.inputzwsgi.errorsFz>The application must return an iterator, if only an empty list)r   r   check_environInputWrapperErrorWrappercheck_iteratorIteratorWrapper)r   r   environr$   iterator)application)r"   r#   r	   lint_app   s    
zvalidator.<locals>.lint_appr   )r,   r-   r   )r,   r	   r      s    )c               @   s<   e Zd Zdd Zdd Zdd Zdd Zd	d
 Zdd ZdS )r&   c             C   s
   || _ d S )N)input)self
wsgi_inputr   r   r	   __init__   s    zInputWrapper.__init__c             G   s0   t t|dk | jj| }t t|tk |S )Nr   )r   r   r.   readr   bytes)r/   r   vr   r   r	   r2      s    zInputWrapper.readc             G   s0   t t|dk | jj| }t t|tk |S )Nr   )r   r   r.   readliner   r3   )r/   r   r4   r   r   r	   r5      s    zInputWrapper.readlinec             G   sN   t t|dk | jj| }t t|tk x|D ]}t t|tk q2W |S )Nr   )r   r   r.   	readlinesr   listr3   )r/   r   linesliner   r   r	   r6      s    
zInputWrapper.readlinesc             c   s    x|   }|sd S |V  qW d S )N)r5   )r/   r9   r   r   r	   __iter__   s
    zInputWrapper.__iter__c             C   s   t dd d S )Nr   z input.close() must not be called)r   )r/   r   r   r	   close   s    zInputWrapper.closeN)	r   r   r   r1   r2   r5   r6   r:   r;   r   r   r   r	   r&      s   r&   c               @   s4   e Zd Zdd Zdd Zdd Zdd Zd	d
 ZdS )r'   c             C   s
   || _ d S )N)errors)r/   wsgi_errorsr   r   r	   r1      s    zErrorWrapper.__init__c             C   s    t t|tk | j| d S )N)r   r   r   r<   write)r/   sr   r   r	   r>      s    zErrorWrapper.writec             C   s   | j   d S )N)r<   flush)r/   r   r   r	   r@      s    zErrorWrapper.flushc             C   s   x|D ]}|  | qW d S )N)r>   )r/   seqr9   r   r   r	   
writelines   s    
zErrorWrapper.writelinesc             C   s   t dd d S )Nr   z!errors.close() must not be called)r   )r/   r   r   r	   r;      s    zErrorWrapper.closeN)r   r   r   r1   r>   r@   rB   r;   r   r   r   r	   r'      s
   r'   c               @   s   e Zd Zdd Zdd ZdS )r   c             C   s
   || _ d S )N)writer)r/   Zwsgi_writerr   r   r	   r1      s    zWriteWrapper.__init__c             C   s   t t|tk | | d S )N)r   r   r3   rC   )r/   r?   r   r   r	   __call__   s    zWriteWrapper.__call__N)r   r   r   r1   rD   r   r   r   r	   r      s   r   c               @   s   e Zd Zdd Zdd ZdS )PartialIteratorWrapperc             C   s
   || _ d S )N)r+   )r/   wsgi_iteratorr   r   r	   r1      s    zPartialIteratorWrapper.__init__c             C   s   t | jd S )N)r)   r+   )r/   r   r   r	   r:     s    zPartialIteratorWrapper.__iter__N)r   r   r   r1   r:   r   r   r   r	   rE      s   rE   c               @   s4   e Zd Zdd Zdd Zdd Zdd Zd	d
 ZdS )r)   c             C   s    || _ t|| _d| _|| _d S )NF)original_iteratoriterr+   closedcheck_start_response)r/   rF   rJ   r   r   r	   r1   	  s    
zIteratorWrapper.__init__c             C   s   | S )Nr   )r/   r   r   r	   r:     s    zIteratorWrapper.__iter__c             C   sT   t | j d t| j}t|tk	r4t dd|f  | jd k	rPt | jd d | _|S )NzIterator read after closedFz$Iterator yielded non-bytestring (%r)zjThe application returns and we started iterating over its body, but start_response has not yet been called)r   rI   nextr+   r   r3   rJ   )r/   r4   r   r   r	   __next__  s    

zIteratorWrapper.__next__c             C   s    d| _ t| jdr| j  d S )NTr;   )rI   hasattrrG   r;   )r/   r   r   r	   r;     s    zIteratorWrapper.closec             C   s"   | j stjd t| j d d S )Nz/Iterator garbage collected without being closed)rI   sysstderrr>   r   )r/   r   r   r	   __del__#  s
    zIteratorWrapper.__del__N)r   r   r   r1   r:   rL   r;   rP   r   r   r   r	   r)     s
   r)   c             C   s  t t| tkdt| | f  x dD ]}t || kd|f  q$W x*dD ]"}t || kd||dd  f  qFW d| krtdt xF|  D ]:}d	|krqt t| | tkd
|t| | | | f  qW t t| d tkd| d f  t | d dkd| d   t	| d  t
| d  | d dkr<td| d  t t | d pX| d dd| d   t | d p| d dd| d   | drt t| d dkd| d   | dst d| kd t | ddkd d S )Nz:Environment is not of the right type: %r (environment: %r))	REQUEST_METHODZSERVER_NAMEZSERVER_PORTzwsgi.versionz
wsgi.inputzwsgi.errorszwsgi.multithreadzwsgi.multiprocesszwsgi.run_oncez$Environment missing required key: %r)ZHTTP_CONTENT_TYPEZHTTP_CONTENT_LENGTHz8Environment should not have the key: %s (use %s instead)   ZQUERY_STRINGzQUERY_STRING is not in the WSGI environment; the cgi module will use sys.argv when this variable is missing, so application errors are more likely.z9Environmental variable %s is not a string: %r (value: %r)zwsgi.versionz#wsgi.version should be a tuple (%r)zwsgi.url_scheme)ZhttpZhttpszwsgi.url_scheme unknown: %rz
wsgi.inputzwsgi.errorsrQ   )ZGETZHEADZPOSTZOPTIONSZPATCHZPUTZDELETEZTRACEzUnknown REQUEST_METHOD: %rZSCRIPT_NAME/z$SCRIPT_NAME doesn't start with /: %rZ	PATH_INFOz"PATH_INFO doesn't start with /: %rZCONTENT_LENGTHr   zInvalid CONTENT_LENGTH: %rzgOne of SCRIPT_NAME or PATH_INFO are required (PATH_INFO should at least be '/' if SCRIPT_NAME is empty)zOSCRIPT_NAME cannot be '/'; it should instead be '', and PATH_INFO should be '/')r   r   dictwarningswarnr   keysr   tuplecheck_inputcheck_errorsget
startswithint)r*   keyr   r   r	   r%   *  sZ    


r%   c             C   s*   x$dD ]}t t| |d| |f  qW d S )N)r2   r5   r6   r:   z-wsgi.input (%r) doesn't have the attribute %s)r   rM   )r0   attrr   r   r	   rZ   k  s    

rZ   c             C   s*   x$dD ]}t t| |d| |f  qW d S )N)r@   r>   rB   z.wsgi.errors (%r) doesn't have the attribute %s)r   rM   )r=   r`   r   r   r	   r[   q  s    

r[   c             C   sv   t | d} | d dd }tt|dkd|  t|}t|dkd|  t| dk sb| d d	krrtd
|  t d S )NStatusr   r   r   z)Status codes must be three characters: %rd   zStatus code is invalid: %r    zjThe status string (%r) should be a three-digit integer followed by a single space and a status explanation)r   splitr   r   r^   rV   rW   r   )r   Zstatus_codeZ
status_intr   r   r	   r   w  s    

r   c             C   s  t t| tkd| t| f  x| D ]}t t|tkd|t|f  t t|dk |\}}t|d}t|d}t | dkd|  t d|kod	|kd
|  t t|d|  t |	d o|	d d|  t
|r$t dd|t
|df  q$W d S )Nz%Headers (%r) must be of type list: %rz1Individual headers (%r) must be of type tuple: %rr   zHeader namezHeader valuer   zyThe Status header cannot be used; it conflicts with CGI script, and HTTP status is not given through headers (value: %r).
:z,Header names may not contain ':' or '\n': %rzBad header name: %r-_z#Names may not end in '-' or '_': %rr   z#Bad header value: %r (bad char: %r))r   r   r7   rY   r   r   lower	header_researchendswithbad_header_value_regroup)r    itemnamer   r   r   r	   r     s,    





r   c             C   s~   t | d} t| d dd }d}x@|D ]8\}}t |d}| dkr(||krRd S tdd|  q(W ||krztdd|  d S )	Nra   r   r   )   i0  zHeader namezcontent-typezJContent-Type header found in a %s response, which must not return content.z,No Content-Type header found in headers (%s))r   r^   re   rj   r   )r   r    codeZNO_MESSAGE_BODYrq   r   r   r   r	   r     s    

r   c             C   s*   t | d kpt| tkd| t| f  d S )Nz exc_info (%r) is not a tuple: %r)r   r   rY   )r!   r   r   r	   r     s    r   c             C   s   t t| ttf d d S )NzwYou should not return a string as your application iterator, instead return a single-item list containing a bytestring.)r   
isinstancer   r3   )r+   r   r   r	   r(     s    r(   )r   __all__rerN   rV   compilerk   rn   Warningr   r   r   r   r&   r'   r   rE   r)   r%   rZ   r[   r   r   r   r   r(   r   r   r   r	   <module>n   s.   

7#		#A