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33.3: Routing - Coggle Diagram

- - - - that captures the value
      - at that position in the URL
  - - - as a key-value pair
    - - the key
        
        has the name of the route parameter
        
        or the property
      - the value
        
        is the value in the URL
  - - - req.params
        
        { mainSection: "what-is-it" }
    - - req.params
        
        { mainSection: "how-it-helps" }
- - - - as a key-value pair
    - - the key
        
        has the name of the query string parameter
        
        or the property
      - the value
        
        is the value in the URL
  - - - req.query
        
        { type: 'style' }
- - - - app.use()
        
        doesn't differentiate between
        
        request verbs
        
        POST
        
        GET
        
        paths
        
        defaults to root
        
        so root and all child paths
        
        will be caught
        
        intercepts all requests to the server
        
        calback will be executed for every request to the app
        
        that matches the specified path
        
        or its children
    - - app.get()
        
        intercepts GET requests to the specifed path ONLY
        
        app.get("/what-is-it", (req, res) => { res.sendFile(path.join(__dirname, "what-is-it.html")); });
        
        res.send()
        
        completes the response
        
        you can't do anything else afterwards
        
        home page
        
        uses root route
        
        app.get("/", (req, res) => { res.sendFile(path.join(__dirname, "overview.html")); });
        
        catch all
        
        app.get("*", (req, res) => { res.send("I don't know that path!!")); });
        
        must come last #
    - - the first matching path/verb will be used
      - if res.send() is called #
        
        that's it - done