Add cetus-nasa program v0.4.0

cetus-nasa uses NASA's API to get Astronomy Picture of the Day.

1 files changed, 109 insertions, 0 deletions

diff --git a/pkg/nasa/apod.go b/pkg/nasa/apod.go
new file mode 100644
index 0000000..62eea96
--- /dev/null
+++ b/pkg/nasa/apod.go
@@ -0,0 +1,109 @@
+// Copyright (c) 2020, Andinus <andinus@inventati.org>
+
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+package nasa
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"net/http"
+	"regexp"
+	"time"
+)
+
+// APOD holds responses
+type APOD struct {
+	Copyright      string `json:"copyright"`
+	Date           string `json:"date"`
+	Explanation    string `json:"explanation"`
+	HDURL          string `json:"hdurl"`
+	MediaType      string `json:"media_type"`
+	ServiceVersion string `json:"service_version"`
+	Title          string `json:"title"`
+	URL            string `json:"url"`
+
+	Code int    `json:"code"`
+	Msg  string `json:"msg"`
+}
+
+// RandDate returns a random date between 1995-06-16 & today
+func RandDate() string {
+	var (
+		min   int64
+		max   int64
+		sec   int64
+		delta int64
+		date  string
+	)
+	min = time.Date(1995, 6, 16, 0, 0, 0, 0, time.UTC).Unix()
+	max = time.Now().UTC().Unix()
+	delta = max - min
+
+	sec = rand.Int63n(delta) + min
+	date = time.Unix(sec, 0).Format("2006-01-02")
+
+	return date
+}
+
+// APODPath returns Astronomy Picture of the Day path
+func APODPath(apodInfo map[string]string, timeout time.Duration) (APOD, error) {
+	var err error
+	apodRes := APOD{}
+
+	// validate date
+	re := regexp.MustCompile("((19|20)\\d\\d)-(0?[1-9]|1[012])-(0?[1-9]|[12][0-9]|3[01])")
+	if !re.MatchString(apodInfo["date"]) {
+		return apodRes, fmt.Errorf("%s does not match format 'YYYY-MM-DD'", apodInfo["date"])
+	}
+
+	client := http.Client{
+		Timeout: time.Second * timeout,
+	}
+
+	req, err := http.NewRequest(http.MethodGet, apodInfo["api"], nil)
+	if err != nil {
+		return apodRes, err
+	}
+	q := req.URL.Query()
+	q.Add("api_key", apodInfo["apiKey"])
+	q.Add("date", apodInfo["date"])
+	req.URL.RawQuery = q.Encode()
+
+	res, err := client.Do(req)
+
+	if err != nil {
+		fmt.Printf("Error: GET %s\n", apodInfo["api"])
+		return apodRes, err
+	}
+	defer res.Body.Close()
+
+	resBody, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return apodRes, err
+	}
+
+	err = json.Unmarshal([]byte(resBody), &apodRes)
+	if err != nil {
+		return apodRes, err
+	}
+
+	if res.StatusCode != 200 {
+		return apodRes, fmt.Errorf("Unexpected response status code received: %d %s",
+			res.StatusCode, http.StatusText(res.StatusCode))
+	}
+
+	return apodRes, err
+}