Repository Structure

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• ./backend/ - contains development scripts, and Kubernetes and Docker configuration files
• ./backend/app - contains backend app source code
• ./frontend/android - contains the Android client source code
• ./frontend/external/ - contains sources of external Android client dependencies

Back-end App Directory Structure

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backend/app/bin/www * Creates and starts the https web server

backend/app/models/userSchema.js * Contains the mongoose schema and model definition for user realted data used in local authentication.

backend/app/models/imageSchema.js * Contains the mongoose schema and model definition for storing images. Expiry of image records is set by reading 'SOURCE_IMAGE_LIFETIME' environment variable value here.

backend/app/models/imageDataSchema.js * Contains the mongoose schema and model definition for image related data and thumbnails.

backend/app/passportSetup * Contains files for passport middleware implementation which are used for local authentication.

backend/app/routes/index.js * Handles API calls to the backend.

backend/app/routes/ocr.js * Handles thumbnail creation and OCR.

backend/app/db.js * Connects backend to the mogodb replica set.

backend/app/app.js * Creates various variables and ties them to used packages, node functionality, routes and implement error handling.

Backend Installation

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Prerequisites

Ubuntu 16.04 with the following installed:

1. Docker
2. Google Cloud SDK
3. Kubernetes client

Tools can be installed by running the following script:

$ ./install_tools.sh

Instructions

• Create a Kubernetes cluster in Google Container Engine and deploy backend app by running the following script:

  $ ./deploy.sh
  

Frontend Installation

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Prerequisites

• Recent JDK in JAVA_HOME or in path
• Recent Android SDK in ANDROID_HOME, with license agreements accepted:
  • SDK build tools 22.0.1
  • SDK Platform 22
  • Android Support Repository
  • Google Repository

To install prerequisites, run:

mkdir AndroidSDK
cd AndroidSDK
wget https://dl.google.com/android/repository/tools_r25.2.3-linux.zip
unzip tools_r25.2.3-linux.zip
./tools/bin/sdkmanager "build-tools;22.0.1" "platforms;android-22" "extras;google;m2repository" "extras;android;m2repository" "add-ons;addon-google_apis-google-22" "extras;google;google_play_services"

Accept license agreements, and run

export ANDROID_HOME=`pwd`
cd ..

You are now set for the next step.

Build and install

Invoke following command in the root folder of the project. BACKEND_URI should point to the IP address or the domain name of the backend, and BACKEND_PORT to the port of the backend.

$ (cd ./frontend/android; ./gradlew installDebug -PBACKEND_URI="<host>" -PBACKEND_PORT=<port> )

Example

$ (cd ./frontend/android; ./gradlew installDebug -PBACKEND_URI="10.1.2.3" -PBACKEND_PORT=443 )

The command will install the app to the attached device. The installed app is a DEBUG version for convenience reasons.

Features

• All project requirements are satisfied
• Challenge: OAuth login has been implemented
• Challenge: Context-awareness offline mode. REMOTE and BENCHMARK modes are disabled when offline. Note that due to OAuth login, login still requires an internet connection.

How to recompile precompiled libraries?

The android application uses native libraries and a custom JNI wrapper for them. For convenience reasons, these are provided in a precompiled form. Should you want to recompile the libraries, you need to compile and configure dependencies defined in frontend/external/libtessbinding/jni/. Then you may invoke ndk-build . in frontend/external/libtessbinding

Frontend App Directory Structure

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/frontend/android/app/src/main/assets/tessdata: * Tesseract training data

/frontend/android/app/src/main/jniLibs: * Precompiled native JNI glue libraries

/frontend/android/app/src/main/java/mcc_2016_g05_p2/niksula/hut/fi/android: * UI screens (Activities) used by the app

/frontend/android/app/src/main/java/mcc_2016_g05_p2/niksula/hut/fi/ocrdriver: * Glue code linking UI logic and OCR operations

/frontend/android/app/src/main/java/mcc_2016_g05_p2/niksula/hut/fi/ocrengine: * Java side of JNI wrapper for tesseract

/frontend/android/app/src/main/java/mcc_2016_g05_p2/niksula/hut/fi/asynctools: * Utils for async results.

/frontend/android/app/src/main/java/mcc_2016_g05_p2/niksula/hut/fi/rpc: * Encapsulation of server connection state, its details and some utilities. * RemoteRPC implements the remote API over SSL to a real backend. * FakeRemoteRPC implements the remote API by faking results. This allows UI testing without actual server connection. * MinimalHTTPSClient reimplements a limited subset of standard library HttpsURLConnection to work around HttpsURLConnection bugs.