push the project

client_side/Client.java

+import org.apache.http.HttpEntity;
+import org.apache.http.client.ClientProtocolException;
+import org.apache.http.client.methods.CloseableHttpResponse;
+import org.apache.http.client.methods.HttpPost;
+import org.apache.http.client.ResponseHandler;
+import org.apache.http.entity.ContentType;
+import org.apache.http.entity.mime.MultipartEntityBuilder;
+import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.HttpClients;
+import org.apache.http.util.EntityUtils;
+import java.io.*;
+import java.net.*;
+import java.util.Scanner;
+
+public class Client{
+
+    private static CloseableHttpClient client = HttpClients.createDefault();
+
+    public static void main(String args[]) throws URISyntaxException, IOException {
+        String image_path = "image.png";
+        String ip_address_path = "ip_address";
+        String endpoint = "/analyseimage";
+
+        String ip_address = readTextFile(ip_address_path);
+        String url_string = "http://"+ip_address+endpoint;
+        URI uri= new URI(url_string);
+        File image_file=new File(image_path);
+        String response = uploadImage(image_file, uri);
+        System.out.println("Response :\n\n"+response);
+    }
+
+    // This code is inspired by https://gist.github.com/kjlubick/70aea8d38831777360c0, consulted on Dec 13 2020.
+
+    private static String uploadImage(File file, URI uri) throws IOException {
+        
+        // This response handler is from https://www.javaguides.net/2019/07/java-http-getpost-request-example.html
+        ResponseHandler < String > responseHandler = response -> {
+            int status = response.getStatusLine().getStatusCode();
+            if (status >= 200 && status < 300) {
+                HttpEntity entity = response.getEntity();
+                return entity != null ? EntityUtils.toString(entity) : null;
+            } else {
+                throw new ClientProtocolException("Unexpected response status: " + status);
+            }
+        };
+        
+        System.out.println("Connection to server : "+uri);
+        HttpPost httpPost = new HttpPost(uri);
+        String response="";
+        try {
+            MultipartEntityBuilder mpeBuilder = MultipartEntityBuilder.create();
+            mpeBuilder.addBinaryBody("image", file);
+            HttpEntity content = mpeBuilder.build();
+            httpPost.setEntity(content);
+            response = client.execute(httpPost, responseHandler);
+        } catch(Exception e ){
+            System.out.println("Error : the file could not be upload.");
+        } finally {
+            httpPost.reset();
+            return response;
+        }
+    }
+
+    // From https://www.w3schools.com/java/java_files_read.asp
+    private static String readTextFile(String path){
+        try {
+            File file = new File(path);
+            Scanner myReader = new Scanner(file);
+            String data="";
+            while (myReader.hasNextLine()) {
+              data += myReader.nextLine();
+            }
+            myReader.close();
+            return data;
+        } catch (FileNotFoundException e) {
+            System.out.println("An error occurred.");
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+ }
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client_side/README.md

+# Client side folder
+
+## How to run the program
+
+To run the client program (source code : [Client.java](./Client.java)) :
+
+1. Run [install_jre.sh](install_jre.sh) if it is not installed yet.
+
+2. Write the server's ip address in [ip_address](ip_address).
+
+3. Run [run.sh](run.sh).
+
+## Kotlin code
+
+I tried to do the program with kotlin ([client.kt](client.kt) and [client.jar](client.jar)). But I kept getting an error, so I switched to java.
+

client_side/client.kt

+/*
+How to compile & launch this program : 
+
+kotlinc client.kt -include-runtime -jvm-target 1.8 -d client.jar
+java -jar client.jar
+
+*/
+
+import java.io.File
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpResponse.BodyHandlers
+import java.net.URI
+import java.nio.file.Path
+
+fun main() {
+    val image_path = "image.png";
+    val url_path = "url";
+
+    // Read the url
+    val url = File(url_path).readText(Charsets.UTF_8);
+
+    println("Image will be sent to : " + url);
+    
+    // Build the client
+    val client = HttpClient.newBuilder().build();
+
+    // Build the request
+    val request = HttpRequest.newBuilder()
+        .header("Content-Type", "image")
+        .POST(HttpRequest.BodyPublishers.ofFile(Path.of(image_path)))
+        .uri(URI.create(url))
+        .build();
+
+
+    // Get the response and print it
+    val response = client.send(request, BodyHandlers.ofString());
+    println(response.body())
+}
+
+
+/*
+
+Basically a copy/paste from https://handyopinion.com/upload-file-to-server-in-android-kotlin/
+
+ 
+
+implementation("com.squareup.okhttp3:okhttp:4.9.0")
+import okhttp3.*
+import okhttp3.MediaType.Companion.toMediaTypeOrNull
+import okhttp3.RequestBody.Companion.asRequestBody
+import java.io.File
+
+fun main() {
+    val image_path = "image.png";
+    val url_path = "url";
+
+    // Read the url
+    val serverURL = File(url_path).readText(Charsets.UTF_8);
+
+    val mimeType = getMimeType(sourceFile);
+    if (mimeType == null) {
+        println("file error : Not able to get mime type")
+        return
+    }
+    val fileName: String = image_path
+    toggleProgressDialog(true)
+    try {
+        val requestBody: RequestBody =
+            MultipartBody.Builder().setType(MultipartBody.FORM)
+                .addFormDataPart("image", fileName,sourceFile.asRequestBody(mimeType.toMediaTypeOrNull()))
+                .build()
+
+        val request: Request = Request.Builder().url(serverURL).post(requestBody).build()
+
+        val response: Response = client.newCall(request).execute()
+
+        if (response.isSuccessful) {
+            println("File uploaded successfully at $serverUploadDirectoryPath$fileName")
+        } else {
+            println("File uploading failed")
+        }
+    } catch (ex: Exception) {
+        println("File uploading failed")
+    }
+}
+*/

client_side/install_jre.sh

+apt update
+apt install openjdk-7-jre
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client_side/ip_address

+172.17.0.2
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client_side/run.sh

+java -jar client.jar
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server_side/README.md

+# Server side folder
+
+## How to run the API
+
+To run the API (source code : [api.py](./api.py)) :
+
+1. Run [install_python_and_flask.sh](install_python_and_flask.sh) if it is not installed yet.
+
+2. Run [run.sh](run.sh).

server_side/api.py

+import flask, os
+from flask import request, jsonify
+from image_analyser import analyse as analyse_image
+
+app = flask.Flask(__name__)
+app.config["DEBUG"] = True
+app.config['upload_folder']="./images"
+
+@app.route('/', methods=['GET', 'POST'])
+def home():
+    return '''
+    <h1>This site is for research purpose</h1>
+    <p>To send an image and receive an answer, use the '/analyseimage' endpoint.</p>'''
+
+'''How to use this endpoint with curl (=on a linux terminal):
+curl -X POST -F 'image=@[path to the image]' http://[ip address]/analyseimage
+'''
+@app.route('/analyseimage', methods=['POST'])
+def api_analyseimage():
+
+    #Store the image as 'images/[hash_of_the_image].[extension]
+    try :
+        file = request.files['image']
+    except :
+        if len(request.files)==1 :
+            file = request.files[
+                list(request.files.keys())[0]   # File = the only element in request.files
+            ]
+        else :
+            return "Error : Image not found."
+    try :
+        extension = os.path.splitext(file.filename)[-1]
+        filename=str(hash(file))+extension
+        filepath = os.path.join(app.config['upload_folder'], filename)
+        file.save(filepath)
+
+        # Analyse the image
+        result=analyse_image(filepath)
+
+        # Remove the image and send back the result
+        os.remove(filepath)
+        return jsonify(result)
+    except :
+        return("Error while analyzing the image.")
+
+@app.errorhandler(404)
+def page_not_found(e):
+    return "<h1>404</h1><p>The resource could not be found.</p>", 404
+
+app.run(host = '0.0.0.0', port=80)
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server_side/image_analyser.py

+from PIL import Image
+
+#Return the first and last pixels
+def analyse(path):
+    try :
+        im = Image.open(path).getdata() #Load the image as a list of tuples
+        im = list(im)
+        return {
+            "First pixel" : str(im[0]),
+            "Last pixel" : str(im[len(im)-1]) 
+        }
+    except :
+        return "Error in the analyse of image"
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server_side/images/README.md

+This folder is used to store images.

server_side/install_python_and_flask.sh

+apt update
+apt install python3-pip
+pip3 install flask
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server_side/run.sh

+python3 api.py
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