views.py

from django.shortcuts import render
from django.template import loader
from django.http import HttpResponse, HttpResponseNotFound, HttpResponseRedirect, Http404
from django.views import generic
from django.contrib.auth import login, logout
from django.conf import settings
from django.contrib.auth.decorators import login_required
from django import forms
from django_tables2 import tables, RequestConfig, columns
from django_tables2.utils import A
from django_filters.views import FilterView
import pyslurm
import os
import docker
import pwd

from .views_tables import QueueTable, DockerImagesTable, SelectFileTable, JobFilesTable, SingularityImagesTable
from .views_forms import JobCreationForm, JobCreationEntrySelectionForm
from .job_submission import *
from .singularity import *
from .pam_authentification_backend import PAMAuthentificationBackend

#get information about a job with a given id
def get_job(id):
    jobs = pyslurm.job().get()
    if id in jobs:
        return jobs[id]
    else:
        return False

#use pwd backend to get uid from linux username
def get_current_user_id(user):
    return pwd.getpwnam(user.username).pw_uid if user else 0

## Generic 404 view
def response_404(message=""):
    return HttpResponseNotFound("<h2>Page not available</h2>{}".format(message))

## Index page
@login_required()
def index_view(request):
    data = pyslurm.job().get()
    jobs = list(data.values())
    table = QueueTable(jobs, user_logged_in=get_current_user_id(request.user))

    table.order_by = '-submit_time'

    stats = {}
    nodes = pyslurm.node().get()
    stats["cpus_util"] = nodes["gpu-server"]["alloc_cpus"]  #FIXME
    stats["cpus_total"] = nodes["gpu-server"]["cpus"]  #FIXME
    stats["ram_util"] = nodes["gpu-server"]["alloc_mem"]  #FIXME
    stats["ram_total"] = nodes["gpu-server"]["real_memory"]  #FIXME
    stats["gpus_util"] = nodes["gpu-server"]["gres_used"]  #FIXME
    stats["gpus_total"] = nodes["gpu-server"]["gres"]  #FIXME

    return render(request, 'job_submission/job_queue.html', {'table': table, 'stats': stats})

##  Job details view
@login_required()
def job_details_view(request, id):
    job_data = get_job(id)

    if job_data:
        # check if the correct user is looking at this..
        if not job_data['user_id'] == get_current_user_id(request.user):
            return response_404('You have no permission to view this job')

        job_out = {'std_out' : '', 'std_out_available' : False}
        # get std out content
        if os.path.isfile(job_data['std_out']):
            with open(job_data['std_out'], 'r') as content_file:
                job_out['std_out'] = content_file.read()
                job_out['std_out_available'] = True
        else:
            job_out['std_out'] = "Log file currently not available"

        file_list = create_sub_file_list(os.path.split(job_data['command'])[0]) #take the same path as the command script
        table = JobFilesTable(file_list, file_color_pattern=settings.FILE_COLOR_TABLE)

        return render(request, 'job_submission/job_details.html', {'job_data' : job_data,
                                                                   'job_data_items' : job_data.items(),
                                                                   'job_out' : job_out,
                                                                   'job_id': id,
                                                                   'files_table': table} )
    else:
        return response_404()

##  Job download std out page
@login_required()
def job_download_std_out_view(request, id):
    job_data = get_job(id)
    if job_data:
        if not job_data['user_id'] == get_current_user_id(request.user):
            return response_404('You have no permission to view this job')

        if not os.path.isfile(job_data['std_out']):
            return response_404()
        with open(job_data['std_out'], 'r') as content_file:
            response = HttpResponse(content_file, content_type='text/plain')
            response['Content-Disposition'] = 'attachment; filename=std_out.txt'
            return response
        return response_404()
    return response_404()


##  Job creation page for singularity images...
@login_required()
def job_create_view(request):
    # process form ...
    if request.method == "POST":
        form = JobCreationForm(request.POST, request.FILES)
        if form.is_valid():
            #get data
            post_data = request.POST.copy()
            temp_path = handle_upload_file(request.FILES['project_files'])

            #save data as session
            request.session['create_temp_path'] = temp_path
            request.session['create_post_data'] = request.POST

            redirect =  HttpResponseRedirect("create_job_entry")
            return redirect
    else:
        form = JobCreationForm()

    #get all available docker contrainers
    containers = get_all_container(settings.SINGULARITY_IMAGES_FOLDER)
    container_features = [get_container_details(x) for x in containers]

    tags = [{'id'       : container['image.filename'],
             'name'     : container['image.filename'],
             'features' : container['Features'],  #Fixme?
             'based_on' : container['org.label-schema.usage.singularity.deffile.from'] } \
            for container in container_features]

    table = SingularityImagesTable(tags)
    table.paginate(page=request.GET.get('page', 1), per_page=25)

    return render(request, 'job_submission/job_creation_form.html', {'form': form, 'available_images': table})



## Job entry file selection
@login_required()
def job_create_select_entrypoint_view(request):
    if request.method == "POST":
        form = JobCreationEntrySelectionForm(request.POST)
        if form.is_valid():
            original_post = request.session["create_post_data"]
            gpu_count = 1 if "gpu_requirements" in original_post else 0
            if request.user.is_authenticated:
                user_id = get_current_user_id(request.user)
                user_email = request.user.email

                submit_job(cpus=original_post['cpu_requirements'],
                           ram=original_post['ram_requirements'],
                           gpus=gpu_count,
                           job_name=original_post['title'],
                           comment=request.POST['comments'],
                           uid=user_id,
                           user_email=user_email,
                           singularity_image=original_post['environment_image'],
                           temp_path=request.session["create_temp_path"],
                           entry_point=request.POST['entry_path'])
            else:
                return response_404()
            return HttpResponseRedirect("create_job_done")
    else:
        form = JobCreationEntrySelectionForm()

    file_list = create_sub_file_list(request.session["create_temp_path"])
    table = SelectFileTable(file_list, file_color_pattern=settings.FILE_COLOR_TABLE)
    return render(request, 'job_submission/job_creation_entry_selection.html', {'form':form, 'entry_files':table})

## Jobs successfully queued
@login_required()
def job_create_done_view(request):
    return render(request, 'job_submission/job_submitted.html')

## Job deletion form and view
@login_required()
def job_remove_view(request):
    if request.method == "POST":
        form = JobRemoveForm(request.POST)
        if form.is_valid():
            #Remove job#TODO! #FIXME
            return HttpResponseRedirect("/queue")
    else:
        form = JobRemoveForm()

    return render(request, 'job_submission/job_remove.html', {'form': form})

@login_required()
def job_details_download_file(request, id, file_id):
    job_data = get_job(id)

    if job_data:
        if not job_data['user_id'] == get_current_user_id(request.user):
            return response_404('You have no permission to view this job')

        file_list = create_sub_file_list(os.path.split(job_data['command'])[0])
        fullpath = ""

        #get matching file id item using a generator
        found_file = next(item for item in file_list if item['file_table_id'] == file_id)
        if found_file:
            fullpath = os.path.join(os.path.split(job_data['command'])[0], found_file['file_table_file'])
        else:
            return response_404("File not found")

        if not os.path.isfile(fullpath):
            return response_404("File not found")

        with open(fullpath, 'rb') as content_file:
            response = HttpResponse(content_file, content_type='application/octet-stream')
            response['Content-Disposition'] = 'attachment; filename={}'.format(os.path.split(fullpath)[1])
            return response

    else:
        return response_404("No job found for this id")

def job_details_download_all_files(request, id):
    job_data = get_job(id)

    if job_data:
        if not job_data['user_id'] == get_current_user_id(request.user):
            return response_404('You have no permission to view this job')

        path = os.path.split(job_data['command'])[0]
        stream = compress_folder_into_zip(path) #package all files into a zip image

        response = HttpResponse(stream.getvalue(), content_type='application/octet-stream')
        response['Content-Disposition'] = 'attachment; filename=job.zip'
        return response

    else:
        return response_404("No job found for this id")


## Login views
def login_view(request):
    username = request.POST['username']
    password = request.POST['password']

    if authenticate(username=username, password=password):
        #success
        login(request, user)
        return HttpResponseRedirect('/queue')
    else:
        #failed
        return render(request, 'job_submission/login.html')

## Logout view
def logout_view(request):
    logout(request)
    return render(request, 'job_submission/logout.html')



################### Helper
# create a list of dicts with all files
def create_sub_file_list(path):
    file_list = []
    file_id = 0
    for root, dirs, files in os.walk(path):
        file_list.append({'file_table_file':os.path.relpath(root, path), 'file_table_type':'root_path', 'file_table_id': -1})
        for file in files:
            file_list.append({'file_table_file':os.path.relpath(os.path.join(root, file), path), 'file_table_type':'file', 'file_table_id': file_id})
            file_id += 1

    return file_list


#### TESTS ...
##  Job creation page for docker images ... #not used anymore
# @login_required()
# def job_create_view(request):
#     # process form ...
#     if request.method == "POST":
#         form = JobCreationForm(request.POST, request.FILES)
#         if form.is_valid():
#             #get data
#             post_data = request.POST.copy()
#             temp_path = handle_upload_file(request.FILES['project_files'])
#
#             #save data as session
#             request.session['create_temp_path'] = temp_path
#             request.session['create_post_data'] = request.POST
#
#             redirect =  HttpResponseRedirect("create_job_entry")
#             return redirect
#     else:
#         form = JobCreationForm()
#
#     #get all available docker contrainers
#     client = docker.from_env()
#     images = client.images.list()
#     tags = [{'id'      : x.id[7:],
#              'tags'    : x.tags,
#              'comment' : x.attrs['Comment'] } \
#             for x in images]
#
#     table = DockerImagesTable(tags)
#     table.paginate(page=request.GET.get('page', 1), per_page=25)
#
#     return render(request, 'job_submission/job_creation_form.html', {'form': form, 'available_images': table})