Request » History » Version 4
Elmer de Looff, 2012-04-27 12:00
Query arguments doc'd
| 1 | 1 | Jan Klopper | h1. Request |
|---|---|---|---|
| 2 | 1 | Jan Klopper | |
| 3 | 3 | Elmer de Looff | The @Request@ object is an abstraction of the incoming HTTP request. This allows one simple interface that is independent of the underlying server that µWeb runs on (either [[Standalone]] using BaseHTTPServer, or [[Apache]] mode on @mod_python@). |
| 4 | 1 | Jan Klopper | |
| 5 | 4 | Elmer de Looff | From PageMaker methods, the request object is accessible as the @self.req@ member. The request object contains all the information about the incoming request: query arguments, post data, cookies and environment data. It is also the object where you define cookies that need to be provided to the client. |
| 6 | 1 | Jan Klopper | |
| 7 | 4 | Elmer de Looff | h1. Query arguments |
| 8 | 4 | Elmer de Looff | |
| 9 | 4 | Elmer de Looff | All query arguments provided by the client are present on the request object. They are also accessible directly on the [[PageMaker]] object. The following code demonstrates both ways to access a query argument: |
| 10 | 4 | Elmer de Looff | |
| 11 | 4 | Elmer de Looff | <pre><code class="python"> |
| 12 | 4 | Elmer de Looff | def QueryTeller(self): |
| 13 | 4 | Elmer de Looff | # Retrieves the 'name' argument from the request object: |
| 14 | 4 | Elmer de Looff | name = self.req.vars['get'].getfirst('name') |
| 15 | 4 | Elmer de Looff | |
| 16 | 4 | Elmer de Looff | # Retrieves the 'name' argument directly from the PageMaker instance (linked to the request): |
| 17 | 4 | Elmer de Looff | name = self.get.getfirst('name') |
| 18 | 4 | Elmer de Looff | return name |
| 19 | 4 | Elmer de Looff | </code></pre> |
| 20 | 4 | Elmer de Looff | |
| 21 | 4 | Elmer de Looff | Using the @getfirst@ method, you get a single string returned from the query argument mapping, or a @None@ if no such value exists. Much like a dictionary's @get@ method, you can provide a second argument to the method, and have that returned instead as the default. |
| 22 | 4 | Elmer de Looff | |
| 23 | 4 | Elmer de Looff | Now, HTTP allows the client to provide the same query argument multiple times. Using @getfirst@ you would only get the very first defined argument. So a request that looks like @http://example.org/group?name=Bob&name=Mark&name=Jenny@ would only return 'Bob' in the previous example. To get all their names printed, you can use the following: |
| 24 | 4 | Elmer de Looff | |
| 25 | 4 | Elmer de Looff | <pre><code class="python"> |
| 26 | 4 | Elmer de Looff | def QueryTeller(self): |
| 27 | 4 | Elmer de Looff | names = self.get.getlist('name') |
| 28 | 4 | Elmer de Looff | return ', '.join(names) |
| 29 | 4 | Elmer de Looff | </code></pre> |
| 30 | 4 | Elmer de Looff | |
| 31 | 4 | Elmer de Looff | This returns a neat comma-separated string with all the provided names. The @getlist@ method does not take a default, but will instead return an empty list when there are no values for the requested argument name. |
| 32 | 1 | Jan Klopper | |
| 33 | 1 | Jan Klopper | h2. Post vars |
| 34 | 1 | Jan Klopper | |
| 35 | 1 | Jan Klopper | POST arguments can be found under: self.post and should be accessed by issueing a 'getfirst()', or 'getlist()' call for the desired key. |
| 36 | 1 | Jan Klopper | self.post.getfirst() allows for a second argument to set a default if the desired key isn't set by the browser |
| 37 | 1 | Jan Klopper | |
| 38 | 1 | Jan Klopper | <pre> |
| 39 | 1 | Jan Klopper | <code class="html"> |
| 40 | 1 | Jan Klopper | argA = self.post.getfirst('argA') |
| 41 | 1 | Jan Klopper | argB = self.post.getfirst('argB', 'empty') |
| 42 | 1 | Jan Klopper | |
| 43 | 1 | Jan Klopper | if 'argA' in self.post: |
| 44 | 1 | Jan Klopper | #pass, argA has been send by the browser |
| 45 | 1 | Jan Klopper | |
| 46 | 1 | Jan Klopper | </code> |
| 47 | 1 | Jan Klopper | </pre> |
| 48 | 1 | Jan Klopper | |
| 49 | 1 | Jan Klopper | h2. Get vars |
| 50 | 1 | Jan Klopper | |
| 51 | 1 | Jan Klopper | GET arguments can be found under: self.get, they work the same as POST vars. |
| 52 | 1 | Jan Klopper | |
| 53 | 1 | Jan Klopper | h2. Cookies |
| 54 | 2 | Elmer de Looff | |
| 55 | 1 | Jan Klopper | self.cookies contains the cookies send by the browser, as the interface to create them from the server. |
| 56 | 1 | Jan Klopper | |
| 57 | 1 | Jan Klopper | h3. Retrieving a cookie |
| 58 | 1 | Jan Klopper | You can fetch the content of cookie by accessig the self.cookie dict with the name of the desired cookie as its key. |
| 59 | 1 | Jan Klopper | The returned cookie object has a value member containing the actual value of the requested cookie. |
| 60 | 1 | Jan Klopper | <pre> |
| 61 | 1 | Jan Klopper | <code class="python"> |
| 62 | 1 | Jan Klopper | self.cookies['sample'].value |
| 63 | 1 | Jan Klopper | </code> |
| 64 | 1 | Jan Klopper | </pre> |
| 65 | 1 | Jan Klopper | |
| 66 | 1 | Jan Klopper | h2. ENV |
| 67 | 1 | Jan Klopper | |
| 68 | 1 | Jan Klopper | The env variable is a dictionary containing the following items; |
| 69 | 1 | Jan Klopper | * CONTENT_TYPE |
| 70 | 1 | Jan Klopper | * CONTENT_LENGTH |
| 71 | 1 | Jan Klopper | * HTTP_COOKIE |
| 72 | 1 | Jan Klopper | * HTTP_HOST |
| 73 | 1 | Jan Klopper | * HTTP_REFERER |
| 74 | 1 | Jan Klopper | * HTTP_USER_AGENT |
| 75 | 1 | Jan Klopper | * PATH_INFO |
| 76 | 1 | Jan Klopper | * QUERY_STRING |
| 77 | 1 | Jan Klopper | * REMOTE_ADDR |
| 78 | 1 | Jan Klopper | * REQUEST_METHOD |
| 79 | 1 | Jan Klopper | * UWEB_MODE 'STANDALONE' / 'MOD_PYTHON' |
| 80 | 1 | Jan Klopper | |
| 81 | 1 | Jan Klopper | h3. Extended env |
| 82 | 1 | Jan Klopper | If more detail is required about the environment, you can issue a call to the self.req.ExtendedEnvironment() method, which will inject more details into the env var. This is a much slower operation than the normal env call, so that's why its tucked away in a separate method. |
| 83 | 1 | Jan Klopper | |
| 84 | 1 | Jan Klopper | * AUTH_TYPE |
| 85 | 1 | Jan Klopper | * CONNECTION_ID |
| 86 | 1 | Jan Klopper | * DOCUMENT_ROOT |
| 87 | 1 | Jan Klopper | * RAW_REQUEST |
| 88 | 1 | Jan Klopper | * REMOTE_HOST |
| 89 | 1 | Jan Klopper | * REMOTE_USER |
| 90 | 1 | Jan Klopper | * SERVER_NAME |
| 91 | 1 | Jan Klopper | * SERVER_PORT |
| 92 | 1 | Jan Klopper | * SERVER_LOCAL_NAME |
| 93 | 1 | Jan Klopper | * SERVER_LOCAL_IP |
| 94 | 1 | Jan Klopper | * SERVER_PROTOCOL |
| 95 | 1 | Jan Klopper | |
| 96 | 2 | Elmer de Looff | And in case of a @mod_python@ setup you will also get: |
| 97 | 1 | Jan Klopper | * MODPYTHON_HANDLER |
| 98 | 1 | Jan Klopper | * MODPYTHON_INTERPRETER |
| 99 | 1 | Jan Klopper | * MODPYTHON_PHASE |