Example of interactions with the Stackexchange API

This web application shows some statistics on answers from Stackoverflow for requested tags. The source of this data is Stackexchange API. After launch one endpoint becomes available, it receives multiple tag parameter in query string - /search?tag=java&tag=clojure. Only last 100 questions by each tag are respects. In response you get pretty json with stats by each of your requested tags - amount of answers for answered questions and total amount of tags among this answers. Queries for these tags are executed in parallel within inner thread pool.

Examples

curl 'http://localhost:8080/search?tag=java&tag=clojure&tag=scala&tag=php&tag=python&tag=ruby&tag=c'

{
  "scala" : {
    "total-tags" : 99,
    "answers" : 5
  },
  "clojure" : {
    "total-tags" : 82,
    "answers" : 31
  },
  "java" : {
    "total-tags" : 100,
    "answers" : 4
  },
  "php" : {
    "total-tags" : 104,
    "answers" : 11
  },
  "python" : {
    "total-tags" : 96,
    "answers" : 7
  },
  "c" : {
    "total-tags" : 79,
    "answers" : 15
  },
  "ruby" : {
    "total-tags" : 92,
    "answers" : 13
  },
  "spent-ms" : 1473
}

Configuration

Configuration available in .env file:

• PORT - http port that app exposes
• POOL_SIZE - size of the thread pool for parallel requests

Launch

• with clojure cli - make run-clj

or

• build jar - make build
• run jar - make run-jar

Measurements

(time
 (app-handler {:request-method :get
               :uri "/search"
               :query-string "tag=cpp&tag=clojure&tag=javascript&tag=php&tag=java&tag=purescript&tag=ruby"
               :pool-size 1}))
;; => "Elapsed time: 8169.954815 msecs"

(time
 (app-handler {:request-method :get
               :uri "/search"
               :query-string "tag=cpp&tag=clojure&tag=javascript&tag=php&tag=java&tag=purescript&tag=ruby"
               :pool-size 2}))
;; => "Elapsed time: 3160.608194 msecs"

(time
 (app-handler {:request-method :get
               :uri "/search"
               :query-string "tag=cpp&tag=clojure&tag=javascript&tag=php&tag=java&tag=purescript&tag=ruby"
               :pool-size 4}))
;; => "Elapsed time: 1399.67507 msecs"

(time
 (app-handler {:request-method :get
               :uri "/search"
               :query-string "tag=cpp&tag=clojure&tag=javascript&tag=php&tag=java&tag=purescript&tag=ruby"
               :pool-size 10}))
;; => "Elapsed time: 685.870774 msecs"

Useful commands

# run dev repl
make repl

# run test
make test

# run via clojure cli
make run-clj

# build ubejar
make build

# run uberjar
make run-jar

Notes

See Makefile for command details