tolitius

package main

import (
	"context"
	"fmt"
	"time"
)

func consume(ctx context.Context, partition int) {

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worker_processes  1;
error_log logs/error.log;
events {
    worker_connections 1024;
}
http {
  init_worker_by_lua_block {
    redis = require("resty.redis")
  }
  server {

tolitius

$ boot repl
boot.user=> (set-env! :dependencies '[[com.rpl/specter "0.13.2"]])
boot.user=> (require '[com.rpl.specter :as s])

boot.user=> (def m {:a 34 :b 28 :c {:bingo 40 :d 23 :e {:bingo 41}} :bingo 42})
#'boot.user/m

boot.user=> (s/select [(s/walker #(and (coll? %)
                                  (= :bingo (first %))))
                       (s/view second)] m)

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data store tools

These tools in reality would probably live behind a protocol for a polymorphic runtime dispatch (i.e. so they can be added to varous store types)

(defn select [conn query]
  (println "reading from" conn "query:" query)
  [1 2 3])

(defn insert [conn query]

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this is the snippet that manages the http server lifecycle:

(defstate web-server :start (start-www config)
                     :stop (.stop web-server))

Trying it

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(defn pcall [f & args]
  (try [true (apply f args)]
  (catch Exception e
    [false e])))

(defn matched? [[status value]]
  (if status
   (when (and value 
              (not= value :nginx-null))
     value)

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While I have not used spec for work before, I followed the hype for several months, and really like the idea.

Overall this workshop, while was the first one of its kind, really "moved" me to actually apply spec to my current Clojure work. In both areas: open source and products for customers.

I believe a "needs improvement" feedback is the most useful one, so don't take it as something I did not like, but rather something others can benefit from in the future attending this workshop.

All that follows is definitely connected to the way I learn things, perceive and digest the information.

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repl time

$ boot repl

boot.user=> (require :reload '[pipeline :refer [engine]]
                             '[mount.core :as mount])
"|| mounting... #'pipeline/engine"

starting it

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(ns cchange
  (:require [mount.core :as mount]))

(defprotocol ChangeListener
  (add-watcher [this ks watcher])
  (on-change [this k]))

(deftype RestartListener [watchers]
  ChangeListener

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starting multiple kafka consumer threads

• Example below is based on gregor, but it could use other Kafka bindings.
• Long CamelCased things come from Java
• defstate comes from mount