Added CGI proxy application

1 files changed, 88 insertions, 0 deletions

diff --git a/paste/cgiapp.py b/paste/cgiapp.py
new file mode 100644
index 0000000..edc156a
--- /dev/null
+++ b/paste/cgiapp.py
@@ -0,0 +1,88 @@
+"""
+Application that runs a CGI script.
+"""
+import os
+import subprocess
+
+__all__ = ['CGIError', 'CGIApplication']
+
+class CGIError(Exception):
+    pass
+
+class CGIApplication(object):
+
+    """
+    This object acts as a proxy to a CGI application.  You pass in the
+    script path (``script``), an optional path to search for the
+    script (if the name isn't absolute) (``path``).  If you don't give
+    a path, then ``$PATH`` will be used.
+    """
+
+    def __init__(self, script, path=None,
+                 include_os_environ=True):
+        self.script_filename = script
+        if isinstance(path, (str, unicode)):
+            path = [path]
+        if path is None:
+            path = os.environ.get('PATH', '').split(':')
+        self.path = path
+        if os.path.abspath(script) != script:
+            # relative path
+            for path_dir in self.path:
+                if os.path.exists(os.path.join(path_dir, script)):
+                    self.script = os.path.join(path_dir, script)
+                    break
+            else:
+                raise CGIError(
+                    "Script %r not found in path %r"
+                    % (script, self.path))
+        else:
+            self.script = script
+        self.include_os_environ = include_os_environ
+
+    def __call__(self, environ, start_response):
+        if self.include_os_environ:
+            cgi_environ = os.environ.copy()
+        else:
+            cgi_environ = {}
+        for name in environ:
+            # Should unicode values be encoded?
+            if (name.upper() == name
+                and isinstance(environ[name], str)):
+                cgi_environ[name] = environ[name]
+        # Default status in CGI:
+        status = '200 OK'
+        headers = []
+        proc = subprocess.Popen(
+            [self.script],
+            stdin=subprocess.PIPE,
+            stdout=subprocess.PIPE,
+            stderr=subprocess.PIPE,
+            env=cgi_environ,
+            cwd=os.path.dirname(self.script),
+            )
+        proc.stdin.write(environ['wsgi.input'].read())
+        stdout = proc.stdout
+        while 1:
+            line = stdout.readline()
+            line = line.rstrip('\n').rstrip('\r')
+            if not line:
+                break
+            if ':' not in line:
+                raise CGIError(
+                    "Bad header line: %r" % line)
+            name, value = line.split(':', 1)
+            value = value.lstrip()
+            name = name.strip()
+            if name.lower() == 'status':
+                status = value
+            else:
+                headers.append((name, value))
+        writer = start_response(status, headers)
+        while 1:
+            data = stdout.read(4096)
+            if not data:
+                break
+            writer(data)
+        environ['wsgi.errors'].write(proc.stderr.read())
+        return []