Added url support and improved error handling

.goreleaser.yml

@@ -38,7 +38,9 @@ archives:
       arm64: 64bit_arm64
 
 checksum:
-  name_template: 'checksums.txt'
+  name_template: 'sha256_checksums.txt'
+  algorithm: sha256
+  
 snapshot:
   name_template: "{{ .Version }}-next"
 changelog:

README.md

@@ -83,10 +83,10 @@ Now, restart any open command prompt and execute "ascii-image-converter -h" for
 
 Note: Decrease font size or increase terminal width (like zooming out) for maximum quality ascii art
 
-The basic usage for converting an image into ascii art is as follows. You can also supply paths to multiple images.
+The basic usage for converting an image into ascii art is as follows. You can also supply multiple image paths and urls.
 
 ```
-ascii-image-converter [image-paths]
+ascii-image-converter [image paths/urls]
 ```
 Example:
 ```
@@ -100,18 +100,18 @@ ascii-image-converter myImage.jpeg
 Display ascii art with the colors from original image. Works with the --negative flag as well.
 
 ```
-ascii-image-converter [image-paths] -C
+ascii-image-converter [image paths/urls] -C
 # Or
-ascii-image-converter [image-paths] --color
+ascii-image-converter [image paths/urls] --color
 ```
 
 #### --complex OR -c
 
 Print the image with a wider array of ascii characters for more detailed lighting density. Sometimes improves accuracy.
 ```
-ascii-image-converter [image-paths] -c
+ascii-image-converter [image paths/urls] -c
 # Or
-ascii-image-converter [image-paths] --complex
+ascii-image-converter [image paths/urls] --complex
 ```
 
 #### --dimensions OR -d
@@ -120,13 +120,13 @@ Note: Don't immediately append another flag with -d
 
 Set the width and height for ascii art in CHARACTER lengths.
 ```
-ascii-image-converter [image-paths] -d <width>,<height>
+ascii-image-converter [image paths/urls] -d <width>,<height>
 # Or
-ascii-image-converter [image-paths] --dimensions <width>,<height>
+ascii-image-converter [image paths/urls] --dimensions <width>,<height>
 ```
 Example:
 ```
-ascii-image-converter [image-paths] -d 100,30
+ascii-image-converter [image paths/urls] -d 100,30
 ```
 
 #### --map OR -m
@@ -135,16 +135,16 @@ Note: Don't immediately append another flag with -m
 
 Pass a string of your own ascii characters to map against. Passed characters must start from darkest character and end with lightest. There is no limit to number of characters.
 
-Notes: Empty spaces can be passed if string is passed inside quotation marks. You can use both single or double quote for quotation marks. For repeating quotation mark inside string, append it with \ (such as  \\").
+Empty spaces can be passed if string is passed inside quotation marks. You can use both single or double quote for quotation marks. For repeating quotation mark inside string, append it with \ (such as  \\").
   
 ```
-ascii-image-converter [image-paths] -m "<string-of-characters>"
+ascii-image-converter [image paths/urls] -m "<string-of-characters>"
 # Or
-ascii-image-converter [image-paths] --map "<string-of-characters>"
+ascii-image-converter [image paths/urls] --map "<string-of-characters>"
 ```
 Following example contains 7 depths of lighting.
 ```
-ascii-image-converter [image-paths] -m " .-=+#@"
+ascii-image-converter [image paths/urls] -m " .-=+#@"
 ```
 
 #### --negative OR -n
@@ -152,23 +152,23 @@ ascii-image-converter [image-paths] -m " .-=+#@"
 Display ascii art in negative colors. Works with both uncolored and colored text from --color flag.
 
 ```
-ascii-image-converter [image-paths] -n
+ascii-image-converter [image paths/urls] -n
 # Or
-ascii-image-converter [image-paths] --negative
+ascii-image-converter [image paths/urls] --negative
 ```
 
 #### --save OR -s
 
 Note: Don't immediately append another flag with -s
 
-Save ascii art in the format `<image-name>-<image-extension>-ascii-art.txt` in the directory path passed to the flag. 
+Save ascii art in the format `<image-name>.<image-extension>-ascii-art.txt` in the directory path passed to the flag.
 
 Example for current directory:
 
 ```
-ascii-image-converter [image-paths] --save .
+ascii-image-converter [image paths/urls] --save .
 # Or
-ascii-image-converter [image-paths] -s .
+ascii-image-converter [image paths/urls] -s .
 ```
 
 #### --formats OR -f
@@ -176,16 +176,16 @@ ascii-image-converter [image-paths] -s .
 Display supported image formats.
 
 ```
-ascii-image-converter [image-paths] --formats
+ascii-image-converter [image paths/urls] --formats
 # Or
-ascii-image-converter [image-paths] -f
+ascii-image-converter [image paths/urls] -f
 ```
 
 <br>
 You can combine flags as well. Following command outputs colored and negative ascii art, with fixed 100 by 30 character dimensions, custom defined ascii characters " .-=+#@" and saves the output in current directory as well.
 
 ```
-ascii-image-converter [image-paths] -Cnd 100,30 -m " .-=+#@" -s ./
+ascii-image-converter [image paths/urls] -Cnd 100,30 -m " .-=+#@" -s ./
 ```
 
 <br>
@@ -196,8 +196,6 @@ You can fork the project and implement any changes you want for a pull request.
 
 ## Packages used
 
-[github.com/spf13/viper](https://github.com/spf13/viper)
-
 [github.com/spf13/cobra](https://github.com/spf13/cobra)
 
 [github.com/mitchellh/go-homedir](https://github.com/mitchellh/go-homedir)
@@ -208,6 +206,8 @@ You can fork the project and implement any changes you want for a pull request.
 
 [github.com/gookit/color](https://github.com/gookit/color)
 
+[github.com/asaskevich/govalidator](https://github.com/asaskevich/govalidator)
+
 ## License
 
 [Apache-2.0](https://github.com/TheZoraiz/ascii-image-converter/blob/master/LICENSE.txt)

cmd/root.go

@@ -16,11 +16,13 @@ limitations under the License.
 package cmd
 
 import (
+	"bytes"
 	"fmt"
 	"image"
 	"io/ioutil"
+	"net/http"
 	"os"
-	"path/filepath"
+	"path"
 	"strings"
 
 	// Image format initialization
@@ -33,10 +35,9 @@ import (
 	_ "golang.org/x/image/webp"
 
 	imgMani "github.com/TheZoraiz/ascii-image-converter/image_manipulation"
-
+	"github.com/asaskevich/govalidator"
-	"github.com/spf13/cobra"
-
 	homedir "github.com/mitchellh/go-homedir"
+	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
 
@@ -53,37 +54,39 @@ var (
 
 	// Root commands
 	rootCmd = &cobra.Command{
-		Use:     "ascii-image-converter [image-paths]",
+		Use:     "ascii-image-converter [image paths/urls]",
-		Short:   "Converts images into ascii format",
+		Short:   "Converts images into ascii art",
-		Version: "1.2.4",
+		Version: "1.2.5",
 		Long:    "This tool converts images into ascii art and prints them on the terminal.\nFurther configuration can be managed with flags.",
-		RunE: func(cmd *cobra.Command, args []string) error {
+
+		// Not RunE since help text is getting larger and seeing it for every error impacts user experience
+		Run: func(cmd *cobra.Command, args []string) {
 
 			if formatsTrue {
-				fmt.Println("Supported image formats: JPEG/JPG, PNG, WEBP, BMP, TIFF/TIF")
+				fmt.Printf("Supported image formats: JPEG/JPG, PNG, WEBP, BMP, TIFF/TIF\n\n")
-				return nil
+				return
 			}
 
 			numberOfDimensions := len(dimensions)
 			if dimensions != nil && numberOfDimensions != 2 {
-				return fmt.Errorf("-d requires 2 dimensions, got %v", numberOfDimensions)
+				fmt.Printf("-d requires 2 dimensions, got %v\n\n", numberOfDimensions)
+				return
 			}
 
 			if len(args) < 1 {
-				return fmt.Errorf("Need at least 1 image path")
+				fmt.Printf("Error: Need at least 1 image path/url\n\n")
+				cmd.Help()
+				return
 			}
 
-			if len(customMap) < 2 && customMap != "" {
+			if customMap != "" && len(customMap) < 2 {
-				fmt.Println("Need at least 2 characters")
+				fmt.Printf("Need at least 2 characters for --map flag\n\n")
-				os.Exit(0)
+				return
 			}
 
 			for _, imagePath := range args {
-				if err := convertImage(imagePath); err != nil {
+				convertImage(imagePath)
-					return err
-				}
 			}
-			return nil
 		},
 	}
 )
@@ -96,97 +99,87 @@ func checkOS() string {
 	}
 }
 
-func convertImage(imagePath string) error {
+func convertImage(imagePath string) {
 
-	pic, err := os.Open(imagePath)
+	// Declared at the start since some variables are initially used in conditional blocks
-	if err != nil {
+	var pic *os.File
-		fmt.Printf("Unable to open file: %v\n", err)
+	var urlImgBytes []byte
-		os.Exit(0)
+	var urlImgName string = ""
+	var err error
+
+	pathIsURl := govalidator.IsRequestURL(imagePath)
+
+	// Different modes of reading data depending upon whether or not imagePath is a url
+	if pathIsURl {
+		fmt.Printf("Fetching image from url...\r")
+
+		retrievedImage, err := http.Get(imagePath)
+		if err != nil {
+			fmt.Printf("Error fetching image: %v\n\n", err)
+			return
+		}
+
+		urlImgBytes, err = ioutil.ReadAll(retrievedImage.Body)
+		if err != nil {
+			fmt.Printf("Failed to read fetched content: %v\n\n", err)
+			return
+		}
+		defer retrievedImage.Body.Close()
+
+		urlImgName = path.Base(imagePath)
+		fmt.Printf("                          \r") // To erase "Fetching image from url..." text from console
+	} else {
+		pic, err = os.Open(imagePath)
+		if err != nil {
+			fmt.Printf("Unable to open file: %v\n\n", err)
+			return
+		}
+		defer pic.Close()
 	}
-	defer pic.Close()
 
-	imData, _, err := image.Decode(pic)
+	var imData image.Image
+
+	if pathIsURl {
+		imData, _, err = image.Decode(bytes.NewReader(urlImgBytes))
+	} else {
+		imData, _, err = image.Decode(pic)
+	}
 	if err != nil {
-		fmt.Printf("Error decoding file: %v\n", err)
+		fmt.Printf("Error decoding %v. %v\n\n", imagePath, err)
-		os.Exit(0)
+		return
 	}
 
 	imgSet, err := imgMani.ConvertToAsciiPixels(imData, dimensions)
 	if err != nil {
-		fmt.Printf("Error: %v\n", err)
+		fmt.Printf("Error: %v\n\n", err)
-		os.Exit(0)
+		return
 	}
 
-	var asciiSet [][]imgMani.AsciiChar
+	asciiSet := imgMani.ConvertToAscii(imgSet, negative, colored, compl, customMap)
-	asciiSet = imgMani.ConvertToAscii(imgSet, negative, colored, compl, customMap)
 
-	var ascii []string
+	ascii := flattenAscii(asciiSet, colored)
-	ascii = flattenAscii(asciiSet, colored)
 
-	// Save art before printing it, if flag is passed
+	// Save ascii art before printing it, if --save flag is passed
 	if savePath != "" {
-		if err := saveAsciiArt(asciiSet, imagePath); err != nil {
+		if err := saveAsciiArt(asciiSet, imagePath, urlImgName); err != nil {
-			fmt.Printf("Error: %v\n", err)
+			fmt.Printf("Error: %v\n\n", err)
-			os.Exit(0)
+			os.Exit(0) // Because this error will be thrown for every image passed to this function if we use "return"
 		}
 	}
 
 	for _, line := range ascii {
 		fmt.Println(line)
 	}
-
-	return nil
-}
-
-func saveAsciiArt(asciiSet [][]imgMani.AsciiChar, imagePath string) error {
-	// To make sure uncolored ascii art is the one saved
-	saveAscii := flattenAscii(asciiSet, false)
-
-	saveFileName, err := createSaveFileName(imagePath)
-	if err != nil {
-		return err
-	}
-
-	savePathLastChar := string(savePath[len(savePath)-1])
-
-	// Check if path is closed with appropriate path separator
-	if savePathLastChar != string(os.PathSeparator) {
-		if checkOS() == "linux" {
-			savePath += "/"
-		} else if checkOS() == "windows" {
-			savePath += "\\"
-		} else {
-			return fmt.Errorf("Path not identified. OS isn't supported")
-		}
-	}
-
-	// If path exists
-	if _, err := os.Stat(savePath); !os.IsNotExist(err) {
-		return ioutil.WriteFile(savePath+saveFileName, []byte(strings.Join(saveAscii, "\n")), 0777)
-	} else {
-		return fmt.Errorf("Save path does not exist.")
-	}
-}
-
-func createSaveFileName(imagePath string) (string, error) {
-	fileInfo, err := os.Stat(imagePath)
-	if err != nil {
-		return "", fmt.Errorf("Can't read file info for saving ascii art.")
-	}
-	currName := fileInfo.Name()
-	extension := filepath.Ext(imagePath)
-	newName := currName[:len(currName)-len(extension)]
-
-	// Something like myImage-jpeg-ascii-art.txt
-	return newName + "-" + extension[1:] + "-ascii-art.txt", nil
 }
 
 // flattenAscii flattens a two-dimensional grid of ascii characters into a one dimension
 // of lines of ascii
 func flattenAscii(asciiSet [][]imgMani.AsciiChar, color bool) []string {
 	var ascii []string
+
 	for _, line := range asciiSet {
 		var tempAscii []string
+
 		for i := 0; i < len(line); i++ {
 			if color {
 				tempAscii = append(tempAscii, line[i].Colored)
@@ -194,11 +187,59 @@ func flattenAscii(asciiSet [][]imgMani.AsciiChar, color bool) []string {
 				tempAscii = append(tempAscii, line[i].Simple)
 			}
 		}
+
 		ascii = append(ascii, strings.Join(tempAscii, ""))
 	}
+
 	return ascii
 }
 
+func saveAsciiArt(asciiSet [][]imgMani.AsciiChar, imagePath string, urlImgName string) error {
+	// To make sure uncolored ascii art is the one saved
+	saveAscii := flattenAscii(asciiSet, false)
+
+	saveFileName, err := createSaveFileName(imagePath, urlImgName)
+	if err != nil {
+		return err
+	}
+
+	savePathLastChar := string(savePath[len(savePath)-1])
+
+	// Check if path is closed with appropriate path separator (depending on OS)
+	if savePathLastChar != string(os.PathSeparator) {
+		if checkOS() == "linux" {
+			savePath += "/"
+		} else {
+			savePath += "\\"
+		}
+	}
+
+	// If path exists
+	if _, err := os.Stat(savePath); !os.IsNotExist(err) {
+		return ioutil.WriteFile(savePath+saveFileName, []byte(strings.Join(saveAscii, "\n")), 0666)
+	} else {
+		return fmt.Errorf("Save path does not exist.")
+	}
+}
+
+func createSaveFileName(imagePath string, urlImgName string) (string, error) {
+	if urlImgName != "" {
+		return urlImgName + "-ascii-art.txt", nil
+	}
+
+	fileInfo, err := os.Stat(imagePath)
+	if err != nil {
+		return "", err
+	}
+
+	currName := fileInfo.Name()
+	currExt := path.Ext(currName)
+	newName := currName[:len(currName)-len(currExt)] // e.g. Grabs myImage from myImage.jpeg
+
+	// Something like myImage.jpeg-ascii-art.txt
+	return newName + "." + currExt[1:] + "-ascii-art.txt", nil
+}
+
 // Cobra configuration from here on
 
 func Execute() {
@@ -218,7 +259,7 @@ func init() {
 	rootCmd.PersistentFlags().BoolVarP(&formatsTrue, "formats", "f", false, "Display supported image formats\n")
 	rootCmd.PersistentFlags().StringVarP(&customMap, "map", "m", "", "Give custom ascii characters to map against\nOrdered from darkest to lightest\ne.g. -m \" .-+#@\" (Quotation marks excluded from map)\n(Cancels --complex flag)\n")
 	rootCmd.PersistentFlags().BoolVarP(&negative, "negative", "n", false, "Display ascii art in negative colors\n(Can work with the --color flag)\n")
-	rootCmd.PersistentFlags().StringVarP(&savePath, "save", "s", "", "Save ascii art in the format:\n<image-name>-<image-extension>-ascii-art.txt\nFile will be saved in passed path\n(pass . for current directory)\n")
+	rootCmd.PersistentFlags().StringVarP(&savePath, "save", "s", "", "Save ascii art in the format:\n<image-name>.<image-extension>-ascii-art.txt\nFile will be saved in passed path\n(pass . for current directory)\n")
 
 	defaultUsageTemplate := rootCmd.UsageTemplate()
 	rootCmd.SetUsageTemplate("\nCopyright © 2021 Zoraiz Hassan <hzoraiz8@gmail.com>\n" +

go.mod

@@ -3,6 +3,7 @@ module github.com/TheZoraiz/ascii-image-converter
 go 1.16
 
 require (
+	github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d // indirect
 	github.com/fsnotify/fsnotify v1.4.9 // indirect
 	github.com/gookit/color v1.4.2
 	github.com/magiconair/properties v1.8.5 // indirect

go.sum

@@ -19,6 +19,8 @@ github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRF
 github.com/armon/circbuf v0.0.0-20150827004946-bbbad097214e/go.mod h1:3U/XgcO3hCbHZ8TKRvWD2dDTCfh9M9ya+I9JpbB7O8o=
 github.com/armon/go-metrics v0.0.0-20180917152333-f0300d1749da/go.mod h1:Q73ZrmVTwzkszR9V5SSuryQ31EELlFMUz1kKyl939pY=
 github.com/armon/go-radix v0.0.0-20180808171621-7fddfc383310/go.mod h1:ufUuZ+zHj4x4TnLV4JWEpy2hxWSpsRywHrMgIH9cCH8=
+github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d h1:Byv0BzEl3/e6D5CLfI0j/7hiIEtvGVFPCZ7Ei2oq8iQ=
+github.com/asaskevich/govalidator v0.0.0-20210307081110-f21760c49a8d/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/bgentry/speakeasy v0.1.0/go.mod h1:+zsyZBPWlz7T6j88CTgSN5bM796AkVf0kBD4zp0CCIs=

image_manipulation/image_conversions.go

@@ -39,7 +39,6 @@ type AsciiPixel struct {
 func ConvertToAsciiPixels(img image.Image, dimensions []int) ([][]AsciiPixel, error) {
 
 	var asciiWidth, asciiHeight int
-
 	var smallImg image.Image
 
 	if len(dimensions) == 0 {
@@ -59,7 +58,8 @@ func ConvertToAsciiPixels(img image.Image, dimensions []int) ([][]AsciiPixel, er
 		// If ascii width exceeds terminal width, change ratio with respect to terminal width
 		if asciiWidth > terminalWidth {
 			smallImg = resize.Resize(uint(terminalWidth), 0, img, resize.Lanczos3)
-			asciiWidth = terminalWidth
+
+			asciiWidth = terminalWidth - 1
 			asciiHeight = smallImg.Bounds().Max.Y - smallImg.Bounds().Min.Y
 
 			// To fix aspect ratio in eventual ascii art

main.go

@@ -16,9 +16,7 @@ limitations under the License.
 
 package main
 
-import (
+import "github.com/TheZoraiz/ascii-image-converter/cmd"
-	"github.com/TheZoraiz/ascii-image-converter/cmd"
-)
 
 func main() {
 	cmd.Execute()

snapcraft.yaml

@@ -1,7 +1,7 @@
 name: ascii-image-converter
 base: core18 
-version: "1.2.4"
+version: "1.2.5"
-summary: Converts images into ascii format
+summary: Converts images into ascii art
 description: |
   This tool converts images into ascii format and prints them onto the terminal window.
   Supported image formats are JPEG/JPG, PNG, WEBP, BMP and TIFF/TIF. Further configuration can be managed by flags.
@@ -27,4 +27,4 @@ apps:
     
 architectures:
   - build-on: amd64
-    run-on: [arm64, armhf, amd64, i386]
+    run-on: [amd64, i386, arm64, armhf, s390x, ppc64el]