5 files changed, 189 insertions(+), 0 deletions(-)

A config.go
A dictionary.go
M go.mod
A go.sum
M main.go

@@ 0,0 1,43 @@
+package main
+
+import (
+	"log"
+	"os"
+
+	"github.com/BurntSushi/toml"
+)
+
+type ConfigFile struct {
+	AwsConfig awsConfig
+}
+
+func loadConfiguration(filePath string) ConfigFile {
+
+	var config ConfigFile
+	if _, err := toml.DecodeFile(filePath, &config); err != nil {
+		log.Fatal(err)
+	}
+
+	return config
+}
+
+type awsConfig struct {
+	IamAccessKeyId     string
+	IamAccessKeySecret string
+	Region             string
+}
+
+func (c *awsConfig) setAwsEnvironmentVariables() {
+	if err := os.Setenv("AWS_ACCESS_KEY_ID", c.IamAccessKeyId); err != nil {
+		log.Fatal(err)
+	}
+	if err := os.Setenv("AWS_SECRET_ACCESS_KEY", c.IamAccessKeySecret); err != nil {
+		log.Fatal(err)
+	}
+	if err := os.Setenv("AWS_DEFAULT_REGION", c.Region); err != nil {
+		log.Fatal(err)
+	}
+	if err := os.Setenv("AWS_REGION", c.Region); err != nil {
+		log.Fatal(err)
+	}
+}

@@ 0,0 1,112 @@
+package main
+
+import (
+	"bytes"
+	"compress/bzip2"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/s3"
+	"github.com/aws/aws-sdk-go/service/s3/s3manager"
+)
+
+func downloadFromS3(filePath string, bucket string, key string) {
+	file, err := os.Create(filePath)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	sess := session.Must(session.NewSession())
+	downloader := s3manager.NewDownloader(sess)
+
+	_, err = downloader.Download(file,
+		&s3.GetObjectInput{
+			Bucket: aws.String(bucket),
+			Key:    aws.String(key),
+		})
+
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	log.Printf("Successfully fetched '%s' item from '%s' bucket in S3. "+
+		"Content written to '%s'\n", key, bucket, filePath)
+}
+
+type DictionaryHandler struct {
+	dictionary map[string]string
+}
+
+func NewDictionaryHandler() *DictionaryHandler {
+	dictHandler := new(DictionaryHandler)
+	dictHandler.loadDictionary()
+	return dictHandler
+}
+
+func (d *DictionaryHandler) loadDictionary() {
+	const dictionaryFileName string = "dictionary.json.bz2"
+	const dictionaryFileS3Bucket string = "pub-static-files"
+	const dictionaryFileS3ObjectKey string = "dictionary.json.bz2"
+
+	if _, err := os.Stat(dictionaryFileName); os.IsNotExist(err) {
+		log.Printf("Didn't find %s file locally, fetching from S3.\n", dictionaryFileName)
+		downloadFromS3(dictionaryFileName, dictionaryFileS3Bucket, dictionaryFileS3ObjectKey)
+	} else {
+		log.Printf("Found the %s file locally. Using that.\n", dictionaryFileName)
+	}
+
+	file, err := os.Open(dictionaryFileName)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	decompressedStream := bzip2.NewReader(file)
+	buf := new(bytes.Buffer)
+	if _, err := buf.ReadFrom(decompressedStream); err != nil {
+		log.Fatal(err)
+	}
+
+	if err := json.Unmarshal([]byte(buf.String()), &d.dictionary); err != nil {
+		log.Fatal(err)
+	}
+}
+
+func (d *DictionaryHandler) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
+	if request.Method == "GET" {
+		lookupWord := request.URL.Path[len("/dictionary/"):]
+		lookupWord = strings.ToLower(lookupWord)
+
+		if lookupWord == "" {
+			// They just asked for /dictionary so let's print some help.
+			formatted := fmt.Sprintf("Hello! You've reached the /dictionary resource. " +
+				"You can get a definition by adding the word you're looking for to the end of the URL.\n\n" +
+				"For example: /dictionary/banana")
+			writer.Write([]byte(formatted))
+		} else {
+			if found, ok := d.dictionary[lookupWord]; ok {
+				// They asked for a valid word. e.g. /dictionary/potato
+				formatted := fmt.Sprintf("Hello! You've just requested the definition of '%s'.\n\n'%s' "+
+					" is defined as: %s\n", lookupWord, lookupWord, found)
+				writer.Write([]byte(formatted))
+				return
+			} else {
+				// They asked for a word that we didn't know. e.g. /dictionary/taters
+				message := fmt.Sprintf("Hello! You've just requested the definition of '%s'. "+
+					"Unfortunately, I don't know that word :(.", lookupWord)
+				writer.Write([]byte(message))
+			}
+		}
+	} else {
+		message := fmt.Sprintf("Hello! You've made a '%s' request to the '%s' resource. "+
+			"Unfortunately, that REST method is not supported at this time.", request.Method, request.URL.Path)
+		writer.Write([]byte(message))
+	}
+
+}

@@ 1,3 1,8 @@
 module git.sr.ht/~zacbrown/api.zacbrown.org
 
 go 1.13
+
+require (
+	github.com/BurntSushi/toml v0.3.1
+	github.com/aws/aws-sdk-go v1.25.43
+)

@@ 0,0 1,6 @@
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
+github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/aws/aws-sdk-go v1.25.43 h1:R5YqHQFIulYVfgRySz9hvBRTWBjudISa+r0C8XQ1ufg=
+github.com/aws/aws-sdk-go v1.25.43/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af h1:pmfjZENx5imkbgOkpRUYLnmbU7UEFbjtDA2hxJ1ichM=
+github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=

@@ 4,12 4,35 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"os"
 )
 
+func getConfigFilePathFromProgramArgs() string {
+	if len(os.Args) >= 2 {
+		path := os.Args[1]
+		if _, err := os.Stat(path); os.IsExist(err) {
+			return path
+		}
+	}
+
+	panic("Not enough arguments provided. Panic time.")
+}
+
 func main() {
+	configFilePath := os.Args[1]
+	config := loadConfiguration(configFilePath)
+	log.Printf("Loaded config file from path '%s'.\n", configFilePath)
+
+	config.AwsConfig.setAwsEnvironmentVariables()
+	log.Println("Setup AWS variables.")
+
 	http.HandleFunc("/", rootFunc)
 	log.Println("Setup root '/' handler.")
 
+	dictionaryHandler := NewDictionaryHandler()
+	http.HandleFunc("/dictionary/", dictionaryHandler.ServeHTTP)
+	log.Println("Setup dictionary '/dictionary' handler.")
+
 	log.Println("Starting server on port 80...")
 	log.Fatal(http.ListenAndServe(":80", nil))
 }