67 lines
1.9 KiB
Racket
67 lines
1.9 KiB
Racket
#lang web-server/insta
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;; A blog is a (listof post)
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;; and a post is a (post title body)
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(struct post (title body))
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;; BLOG: blog
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;; The static blog.
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(define BLOG
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(list (post "Second Post" "This is another post")
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(post "First Post" "This is my first post")))
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;; start: request -> response
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;; Consumes a request and produces a page that displays all of the
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;; web content.
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(define (start request)
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(local [(define a-blog
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(cond [(can-parse-post? (request-bindings request))
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(cons (parse-post (request-bindings request))
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BLOG)]
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[else
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BLOG]))]
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(render-blog-page a-blog request)))
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;; can-parse-post?: bindings -> boolean
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;; Produces true if bindings contains values for 'title and 'body.
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(define (can-parse-post? bindings)
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(and (exists-binding? 'title bindings)
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(exists-binding? 'body bindings)))
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;; parse-post: bindings -> post
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;; Consumes a bindings, and produces a post out of the bindings.
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(define (parse-post bindings)
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(post (extract-binding/single 'title bindings)
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(extract-binding/single 'body bindings)))
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;; render-blog-page: blog request -> response
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;; Consumes a blog and a request, and produces an HTML page
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;; of the content of the blog.
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(define (render-blog-page a-blog request)
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(response/xexpr
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`(html (head (title "My Blog"))
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(body
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(h1 "My Blog")
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,(render-posts a-blog)
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(form
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(input ((name "title")))
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(input ((name "body")))
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(input ((type "submit"))))))))
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;; render-post: post -> xexpr
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;; Consumes a post, produces an xexpr fragment of the post.
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(define (render-post a-post)
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`(div ((class "post"))
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,(post-title a-post)
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(p ,(post-body a-post))))
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;; render-posts: blog -> xexpr
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;; Consumes a blog, produces an xexpr fragment
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;; of all its posts.
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(define (render-posts a-blog)
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`(div ((class "posts"))
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,@(map render-post a-blog)))
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