--- /dev/null
+
+/*
+ * Create a shortcut on a number key to jump to a named slide.
+ *
+ * Using the hotkey on the target slide will go "back" to the slide that was active before jumping
+ * to the target slide.
+ *
+ * Example: Jump to the slide named "myslide" when the "1" key is pressed.
+ * createHotkey(1, 'myslide');
+ */
+function createHotkey(key, slideName) {
+ var targetSlide = slideshow.getSlideByName(slideName);
+ var lastSlide = -1;
+ document.addEventListener('keydown', function(e) {
+ if (e.which === key + 48) {
+ var currentNum = slideshow.getCurrentSlideIndex() + 1;
+ var targetNum = targetSlide.getSlideIndex() + 1;
+ if (currentNum !== targetNum) {
+ lastSlide = currentNum;
+ slideshow.gotoSlide(targetNum);
+ }
+ else {
+ slideshow.gotoSlide(lastSlide);
+ }
+ }
+ });
+};
+
+/*
+ * Set a hotkey "u" to navigate backwards in time.
+ *
+ * If you get on the wrong slide, this might be the easiest way to get back on track. This is what
+ * you might expect the browser's "Back" button to do if it worked.
+ */
+(function() {
+ var history = [];
+ var skip = false;
+ slideshow.on('hideSlide', function(slide) {
+ if (skip) {
+ skip = false;
+ return;
+ }
+ history.push(slide.getSlideIndex() + 1);
+ });
+ document.addEventListener('keydown', function(e) {
+ if (e.which === 85 /* [u]ndo */) {
+ var lastNum = history.pop();
+ if (lastNum) {
+ skip = true;
+ slideshow.gotoSlide(lastNum);
+ }
+ }
+ });
+})();
+
---
-class: center, middle
+class: center, middle
+name: psgi-flow1
## Extremely High-level Overview
---
-class: center, middle
+class: center, middle
+name: psgi-flow2
## Pretty High-level Overview
---
-class: center, middle
+class: center, middle
+name: psgi-flow3
## Somewhat High-level Overview
---
-class: center, middle
+class: center, middle
+name: psgi-flow4
## Somewhat High-level Overview
---
-class: center, middle
+class: center, middle
+name: psgi-flow5
## High-level Overview
???
- A web framework makes it so your app doesn't need to speak HTTP or CGI or even PSGI.
- -
---
--
- The IETF and W3C took over standards development, resulting in [RFC 1945](https://tools.ietf.org/html/rfc1945) ("HTTP 1.0") in 1996.
+???
+- IETF = Internet Engineering Task Force
+- W3C = World Wide Web Consortium
+
--
- [RFC 2068](https://tools.ietf.org/html/rfc2068) ("HTTP 1.1") happened in 1997, superceded by [RFC 2616](https://tools.ietf.org/html/rfc2616) in 1999.
```http
GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
```http
*GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
```http
GET /ip HTTP/1.1
*User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-*Host: foo.acme.tld
+*Host: localhost
*Accept-Language: en-us
*Connection: Keep-Alive
```
HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
```http
GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
```http
GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
*HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
```http
GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
HTTP/1.1 200 OK
*Date: Thu, 07 Jul 2016 11:56:23 GMT
*Server: nginx
-*Content-Length: 30
+*Content-Length: 29
*Content-Type: text/plain
*Connection: Closed
```http
GET /ip HTTP/1.1
User-Agent: Mozilla/5.0 (X11; Linux x86_64)
-Host: foo.acme.tld
+Host: localhost
Accept-Language: en-us
Connection: Keep-Alive
```
HTTP/1.1 200 OK
Date: Thu, 07 Jul 2016 11:56:23 GMT
Server: nginx
-Content-Length: 30
+Content-Length: 29
Content-Type: text/plain
Connection: Closed
]
???
+- In Perl, you can get these using %ENV.
+- Or getenv from stdlib.
- If you've done some web programming before, you're probably familiar with at least a few of these.
---
producing correctly-formatted headers, and even producing HTML.
- CGI.pm was deprecated in perl 5.20 and remove from core in perl 5.22.
-TODO make a slide for this
Good:
- Conceptually simple.
- Only requires the use of the most basic and primitive program constructs (stdin, stdout, env).
+- Only other primitive construct that could have been used is that of passing program arguments.
+ - Actually, the spec does specify behavior for "search-strings" as program arguments.
Bad:
- Details can get complicated.
???
- Unlike the interfaces we have examined so far, mod_perl is code.
+- About the same time as FastCGI.
--
- Became an Apache Software Foundation project at ApacheCon 1999 in Orlando.
```
???
-- There's a separate mod_perl for nginx.
+- Notice how we're not using STDOUT (or even pretending to).
+- This program actually runs on a perl interpreter inside the web server.
+- It also has access to more information through the exposed API.
Good:
- Can run CGI programs as-is.
Bad:
- Can tie you to specific web servers.
+ - There's a separate mod_perl for nginx.
- Code runs in the same process as the HTTP server -- kinda scary.
- Using Apache's API feels heavy.
};
```
+???
+- I think it's good to understand CGI et al. so that you can understand why it was designed the way
+ it was.
+- Hopefully the ideas behind PSGI are based off of the best that CGI et al. had to offer without any
+ of the drawbacks.
+
+
+- Notice how the program is a subroutine.
+- By being a subrouting rather than a script that is executed, we're already in a form that can be
+ called repeatedly without incurring fork-exec overhead. Nice!
+
---
```perl
1. Hashref of request information.
]
+???
+- Oh, look! The variable is the same as is specified by CGI.
+ - Why throw away over a decade of convention?
+
---
```perl
1. HTTP status code.
]
+???
+- Then you'll notice that instead of printing anything, we return an arrayref as the response.
+
---
```perl
]
]
-</textarea><script src="https://gnab.github.io/remark/downloads/remark-latest.min.js"></script><script>var slideshow = remark.create({countIncrementalSlides: true, highlightLanguage: 'perl', highlightLines: true, ratio: '16:9', /*slideNumberFormat: '',*/ navigation: {scroll: false, touch: false, click: false}})</script></body></html>
+</textarea><script src="https://gnab.github.io/remark/downloads/remark-latest.min.js"></script><script>var slideshow = remark.create({countIncrementalSlides: true, highlightLanguage: 'perl', highlightLines: true, ratio: '16:9', /*slideNumberFormat: '',*/ navigation: {scroll: false, touch: false, click: false}})</script><script src="js/common.js"></script><script src="js/slides.js"></script></body></html>
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projects / chaz / talk-introduction-to-psgi / commitdiff
