Setting `PYTHONUNBUFFERED` to a non empty value ensures that the python output is sent straight to terminal (e.g. your container log) without being first buffered and that you can see the output of your application (e.g. django logs) in real time.

This also ensures that no partial output is held in a buffer somewhere and never written in case the python application crashes.

References:

* https://docs.python.org/3/using/cmdline.html#envvar-PYTHONUNBUFFERED
* https://alphacoder.xyz/dockerizing-django/
* https://towardsdatascience.com/how-to-contain-your-first-django-in-docker-and-access-it-from-aws-fdb0081bdf1d

`PYTHONUNBUFFERED` non empty value force the stdout and stderr streams to be unbuffered. This option has no effect on the stdin stream



I was looking at the source code for [nmap](https://en.wikipedia.org/wiki/Nmap) that was released in 1997 and I noticed this section of code that looks a little odd to me:

    int i=0, j=0,start,end;
    char *expr = strdup(origexpr);
    ports = safe_malloc(65536 * sizeof(short));
    i++;                                         /* &lt;&lt;&lt;&lt;&lt;&lt; */
    i--;                                         /* &lt;&lt;&lt;&lt;&lt;&lt; */
    for(;j &lt; exlen; j++) 
      if (expr[j] != &#39; &#39;) expr[i++] = expr[j]; 
    expr[i] = &#39;\0&#39;;

Why would you have `i++;` and then `i--;` right after each other? `i` is `0`, then `i++` turns `i` to `1`. After that, `i--` turns `i` to `0`.

[Link to original source code.][1] Search for:

    i++;
    i--;

Can anyone explain what this is for?


  [1]: https://nmap.org/p51-11.html



Why have i++; i--; right after each other?

I want to toggle only running one test, so I don&#39;t have to wait for my other tests to see the result of one test.

Currently, I comment out my other tests, but this is really annoying.

Is there a way to toggle only running one test in `Cypress`?



Cypress: run only one test

I was watching a tutorial to dockerize my django application. I did not understand why we use `PYTHONUNBUFFERED` as environment variable in *DockerFile*. 

Can you please help?

What is the use of PYTHONUNBUFFERED in docker file?

I was watching a tutorial to dockerize my django application. I did not understand why we use <code>PYTHONUNBUFFERED</code> as environment variable in DockerFile.
Can you please help?

I&#39;m upgrading an application from Django 1.11.25 (Python 2.6) to Django 3.1.3 (Python 3.8.5) and, when I run `manage.py makemigrations`, I receive this messasge:

```
  File &quot;/home/eduardo/projdevs/upgrade-intra/corporate/models/section.py&quot;, line 9, in &lt;module&gt;
    from authentication.models import get_sentinel**

ImportError: cannot import name &#39;get_sentinel&#39; from partially initialized module &#39;authentication.models&#39; (most likely due to a circular import) (/home/eduardo/projdevs/upgrade-intra/authentication/models.py)**
```
My models are:

**authentication / models.py**

    from django.conf import settings
    from django.contrib.auth.models import AbstractUser, UserManager
    from django.db import models
    from django.db.models.signals import post_save
    from django.utils import timezone

    from corporate.constants import GROUP_SUPPORT
    from corporate.models import Phone, Room, Section
    from library.exceptions import ErrorMessage
    from library.model import update_through_dict
    from .constants import INTERNAL_USER, EXTERNAL_USER, SENTINEL_USERNAME, SPECIAL_USER, USER_TYPES_DICT


    class UserProfile(models.Model):
        user = models.OneToOneField(
            &#39;User&#39;,
            on_delete=models.CASCADE,
            unique=True,
            db_index=True
        )
        ...
        phone = models.ForeignKey(&#39;corporate.Phone&#39;, on_delete=models.SET_NULL, ...)
        room = models.ForeignKey(&#39;corporate.Room&#39;, on_delete=models.SET_NULL, ...)
        section = models.ForeignKey(&#39;corporate.Section&#39;, on_delete=models.SET_NULL, ...)
        objects = models.Manager()
        ...

    class CustomUserManager(UserManager):

        def __init__(self, type=None):
            super(CustomUserManager, self).__init__()
            self.type = type

        def get_queryset(self):
            qs = super(CustomUserManager, self).get_queryset()
            if self.type:
                qs = qs.filter(type=self.type).order_by(&#39;first_name&#39;, &#39;last_name&#39;)
            return qs

        def get_this_types(self, types):
            qs = super(CustomUserManager, self).get_queryset()
            qs = qs.filter(type__in=types).order_by(&#39;first_name&#39;, &#39;last_name&#39;)
            return qs

        def get_all_excluding(self, types):
            qs = super(CustomUserManager, self).get_queryset()
            qs = qs.filter(~models.Q(type__in=types)).order_by(&#39;first_name&#39;, &#39;last_name&#39;)
            return qs

    class User(AbstractUser):
        type = models.PositiveIntegerField(&#39;...&#39;, default=SPECIAL_USER)
        username = models.CharField(&#39;...&#39;, max_length=256, unique=True)
        first_name = models.CharField(&#39;...&#39;, max_length=40, blank=True)
        last_name = models.CharField(&#39;...&#39;, max_length=80, blank=True)
        date_joined = models.DateTimeField(&#39;...&#39;, default=timezone.now)
        previous_login = models.DateTimeField(&#39;...&#39;, default=timezone.now)

        objects = CustomUserManager()
        ...
        def get_profile(self):
            if self.type == INTERNAL_USER:
                ...
            return None

        def get_or_create_profile(self):
            profile = self.get_profile()
            if not profile and self.type == INTERNAL_USER:
                ...
            return profile

        def update(self, changes):
            ...

    class ExternalUserProxy(User):
        objects = CustomUserManager(type=EXTERNAL_USER)

        class Meta:
            proxy = True
            verbose_name = &#39;...&#39;
            verbose_name_plural = &#39;...&#39;

    class InternalUserProxy(User):
        objects = CustomUserManager(type=INTERNAL_USER)

        class Meta:
            proxy = True
            verbose_name = &#39;...&#39;
            verbose_name_plural = &#39;...&#39;

    def create_profile(sender, instance, created, **kwargs):
        if created and instance.type == INTERNAL_USER:
            try:
                profile = UserProfile()
                profile.user = instance
                profile.save()
            except:
                pass

    post_save.connect(create_profile, sender=User)

    def get_sentinel():
        try:
            sentinel = User.objects.get(username__exact=SENTINEL_USERNAME)
        except User.DoesNotExist:
            settings.LOGGER.error(&quot;...&quot;)
            from django.contrib.auth.models import Group
            sentinel = User()
            sentinel.username = SENTINEL_USERNAME
            sentinel.first_name = &quot;...&quot;
            sentinel.last_name = &quot;...&quot;
            sentinel.set_unusable_password()
            sentinel.save()
            technical = Group.objects.get(name=GROUP_SUPPORT)
            sentinel = User.objects.get(username__exact=SENTINEL_USERNAME)
            sentinel.groups.add(technical)
            sentinel.save()
        return sentinel

**corporate / models / ```__init__.py```**

    ...
    from .section import Section
    ...

**corporate / models / section.py**

    from django.conf import settings
    from authentication.models import get_sentinel
    from .room import Room

    class Section(models.Model):
        ...
        boss = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.SET(get_sentinel), ...)
        surrogate = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.SET(get_sentinel), ...)
        room = models.ForeignKey(Room, on_delete=models.SET_NULL, ...)
        is_subordinate_to = models.ForeignKey(&#39;self&#39;, on_delete=models.SET_NULL, ...)
        ...

What am I doing wrong?

ImportError: cannot import name &#39;...&#39; from partially initialized module &#39;...&#39; (most likely due to a circular import)

I just updated my python from 3.9.1 to 3.9.4. When I tried to run the server. The console gave me a warning for this:

```
WARNINGS:
learning_logs.Entry: (models.W042) Auto-created primary key used when not defining a primary key type, by default &#39;django.db.models.AutoField&#39;.
HINT: Configure the DEFAULT_AUTO_FIELD setting or the LearningLogsConfig.default_auto_field attribute to point to a subclass of AutoField, e.g. &#39;django.db.models.BigAutoField&#39;.
learning_logs.Topic: (models.W042) Auto-created primary key used when not defining a primary key type, by default &#39;django.db.models.AutoField&#39;.
HINT: Configure the DEFAULT_AUTO_FIELD setting or the LearningLogsConfig.default_auto_field attribute to point to a subclass of AutoField, e.g. &#39;django.db.models.BigAutoField&#39;.
No changes detected in app &#39;learning_logs&#39;
```

May I please know how do I fix this. 
I read the documentation about this, but I don&#39;t understand how this part [this page][2] relates to this.

Models.py

    from django.db import models
    from django.contrib.auth.models import User
    # Create your models here.
    
    class Topic(models.Model):
        text = models.CharField(max_length = 200)
        date_added = models.DateTimeField(auto_now_add = True)
        image = models.ImageField(upload_to = &#39;backgroud_images&#39;, null = True, blank = True)
        owner = models.ForeignKey(User,on_delete = models.CASCADE)
        def __str__(self):
            return self.text
    
    
    
    class Entry(models.Model):
        topic = models.ForeignKey(Topic,on_delete = models.CASCADE)
        text = models.TextField()
        date_added = models.DateTimeField(auto_now_add = True)
    
        class Meta:
            verbose_name_plural = &quot;Entries&quot;
    
        def __str__(self):
            return self.text[:50]


  [1]: https://i.stack.imgur.com/xX2AS.png
  [2]: https://docs.djangoproject.com/en/3.1/topics/db/models/

Auto-create primary key used when not defining a primary key type warning in Django

I have done server setup multiple times with the same settings but this time, I am seeing the error message. It is not even allowing to migrate the database. 

    System check identified no issues (0 silenced).
    Exception in thread django-main-thread:
    Traceback (most recent call last):
      File &quot;/usr/lib/python3.9/threading.py&quot;, line 954, in _bootstrap_inner
        self.run()
      File &quot;/usr/lib/python3.9/threading.py&quot;, line 892, in run
        self._target(*self._args, **self._kwargs)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/utils/autoreload.py&quot;, line 53, in wrapper
        fn(*args, **kwargs)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/core/management/commands/runserver.py&quot;, line 120, in inner_run
        self.check_migrations()
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/core/management/base.py&quot;, line 458, in check_migrations
        executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/migrations/executor.py&quot;, line 18, in __init__
        self.loader = MigrationLoader(self.connection)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/migrations/loader.py&quot;, line 49, in __init__
        self.build_graph()
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/migrations/loader.py&quot;, line 212, in build_graph
        self.applied_migrations = recorder.applied_migrations()
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/migrations/recorder.py&quot;, line 77, in applied_migrations
        return {(migration.app, migration.name): migration for migration in self.migration_qs}
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/query.py&quot;, line 276, in __iter__
        self._fetch_all()
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/query.py&quot;, line 1261, in _fetch_all
        self._result_cache = list(self._iterable_class(self))
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/query.py&quot;, line 57, in __iter__
        results = compiler.execute_sql(chunked_fetch=self.chunked_fetch, chunk_size=self.chunk_size)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/sql/compiler.py&quot;, line 1170, in execute_sql
        return list(result)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/sql/compiler.py&quot;, line 1569, in cursor_iter
        for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/models/sql/compiler.py&quot;, line 1569, in &lt;lambda&gt;
        for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/utils.py&quot;, line 97, in inner
        return func(*args, **kwargs)
      File &quot;/home/datanal/datanal-samply/venv/lib/python3.9/site-packages/django/db/backends/postgresql/utils.py&quot;, line 6, in utc_tzinfo_factory
        raise AssertionError(&quot;database connection isn&#39;t set to UTC&quot;)
    AssertionError: database connection isn&#39;t set to UTC


Here is my settings.py for timezone. 

    LANGUAGE_CODE = &#39;en-us&#39;
    
    TIME_ZONE = &#39;UTC&#39;
    
    USE_I18N = True
    
    USE_L10N = True
    
    USE_TZ = True

OS: Ubuntu 21.04
Python Version : 3.9.5
Django Version: 3.0
PostgreSQL: 13.3 


I have also gone through [another question][1] but did not find any solution. Is there anyone who can help me to get this done? I have multiple server setup with same code without changing anything and worked but this time it is not. 


  [1]: https://stackoverflow.com/questions/38807296/django-1-9-2-assertionerror-database-connection-isnt-set-to-utc

AssertionError: database connection isn&#39;t set to UTC

After upgrading to Django 4.0, I get the following error when running `python manage.py runserver`

```
  ...
  File &quot;/path/to/myproject/myproject/urls.py&quot;, line 16, in &lt;module&gt;
    from django.conf.urls import url
ImportError: cannot import name &#39;url&#39; from &#39;django.conf.urls&#39; (/path/to/my/venv/lib/python3.9/site-packages/django/conf/urls/__init__.py)
```

My urls.py is as follows:

```
from django.conf.urls

from myapp.views import home

urlpatterns = [
    url(r&#39;^$&#39;, home, name=&quot;home&quot;),
    url(r&#39;^myapp/&#39;, include(&#39;myapp.urls&#39;),
]
```

ImportError: cannot import name &#39;url&#39; from &#39;django.conf.urls&#39; after upgrading to Django 4.0

I have a docker-compose file and a Dockerfile. MySQL is installed properly. I have set **MYSQL_ROOT_PASSWORD**. But when trying to access mysql db, getting the error - Access denied. I have read the other threads of this site, but couldn&#39;t get that much help. :( 

Here is my docker-compose file:

    version: &#39;3&#39;
    
    volumes:
            db_data: {}
    
    services:
        db:
            build:
                context: .
                dockerfile: ./db/Dockerfile
                args:
                    - database=iTel
                    - password=123
            image: db_image
            volumes:
                - db_data:/var/lib/mysql
            ports:
                - &quot;3306:3306&quot;

and Dockerfile:

    FROM mysql:5.7.15
    
    ARG database
    ARG password
    
    RUN echo ${database}
    RUN echo ${password}
    
    MAINTAINER me
    ENV MYSQL_DATABASE=${database} \
        MYSQL_ROOT_PASSWORD=${password}
    ADD ./db/database100.sql /docker-entrypoint-initdb.d
    EXPOSE 3306

Here are logs for build:

    docker-compose up -d

    Building db
    Step 1/9 : FROM mysql:5.7.15
    5.7.15: Pulling from library/mysql
    6a5a5368e0c2: Pull complete
    0689904e86f0: Pull complete
    486087a8071d: Pull complete
    3eff318f6785: Pull complete
    3df41d8a4cfb: Pull complete
    1b4a00485931: Pull complete
    0bab0b2c2630: Pull complete
    264fc9ce512d: Pull complete
    e0181dcdbbe8: Pull complete
    53b082fa47c7: Pull complete
    e5cf4fe00c4c: Pull complete
    Digest: sha256:966490bda4576655dc940923c4883db68cca0b3607920be5efff7514e0379aa7
    Status: Downloaded newer image for mysql:5.7.15
     ---&gt; 18f13d72f7f0
    Step 2/9 : ARG database
     ---&gt; Running in 62819f9fc38b
    Removing intermediate container 62819f9fc38b
     ---&gt; 863fd3212046
    Step 3/9 : ARG password
     ---&gt; Running in ea9d36c1a954
    Removing intermediate container ea9d36c1a954
     ---&gt; 056100b1d5eb
    Step 4/9 : RUN echo ${database}
     ---&gt; Running in 941bd2f4fc58
    iTel
    Removing intermediate container 941bd2f4fc58
     ---&gt; 7b2b48e7bd8c
    Step 5/9 : RUN echo ${password}
     ---&gt; Running in 9cb80396bb62
    123
    Removing intermediate container 9cb80396bb62
     ---&gt; 155d184c78ba
    Step 6/9 : MAINTAINER me
     ---&gt; Running in 8e3b3b53ce7b
    Removing intermediate container 8e3b3b53ce7b
     ---&gt; 9a7617a24800
    Step 7/9 : ENV MYSQL_DATABASE=${database}     MYSQL_ROOT_PASSWORD=${password}
     ---&gt; Running in e483e65caf55
    Removing intermediate container e483e65caf55
     ---&gt; acf8ac829607
    Step 8/9 : ADD ./db/database100.sql /docker-entrypoint-initdb.d
     ---&gt; 42d992439f98
    Step 9/9 : EXPOSE 3306
     ---&gt; Running in 4e138502c6f9
    Removing intermediate container 4e138502c6f9
     ---&gt; a0818deda593
    Successfully built a0818deda593
    Successfully tagged db_image:latest
    WARNING: Image for service db was built because it did not already exist. To rebuild this image you must use `docker-compose build` or `docker-compose up --build`.
    Creating reve_db_1 ... done

to see the containers:

    docker ps -a

    CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                    NAMES
    49419cb9980a        db_image            &quot;docker-entrypoint.s…&quot;   10 seconds ago      Up 8 seconds        0.0.0.0:3306-&gt;3306/tcp   reve_db_1

That is log for this container:

    docker logs 49419cb9980a

    2020-01-21T07:53:13.050129Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
    2020-01-21T07:53:13.051767Z 0 [Note] mysqld (mysqld 5.7.15) starting as process 1 ...
    2020-01-21T07:53:13.054945Z 0 [Note] InnoDB: PUNCH HOLE support available
    2020-01-21T07:53:13.055053Z 0 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
    2020-01-21T07:53:13.055103Z 0 [Note] InnoDB: Uses event mutexes
    2020-01-21T07:53:13.055179Z 0 [Note] InnoDB: GCC builtin __atomic_thread_fence() is used for memory barrier
    2020-01-21T07:53:13.055226Z 0 [Note] InnoDB: Compressed tables use zlib 1.2.3
    2020-01-21T07:53:13.055268Z 0 [Note] InnoDB: Using Linux native AIO
    2020-01-21T07:53:13.055608Z 0 [Note] InnoDB: Number of pools: 1
    2020-01-21T07:53:13.055791Z 0 [Note] InnoDB: Using CPU crc32 instructions
    2020-01-21T07:53:13.061164Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M
    2020-01-21T07:53:13.072998Z 0 [Note] InnoDB: Completed initialization of buffer pool
    2020-01-21T07:53:13.075325Z 0 [Note] InnoDB: If the mysqld execution user is authorized, page cleaner thread priority can be changed. See the man page of setpriority().
    2020-01-21T07:53:13.101337Z 0 [Note] InnoDB: Highest supported file format is Barracuda.
    2020-01-21T07:53:13.142134Z 0 [Note] InnoDB: Creating shared tablespace for temporary tables
    2020-01-21T07:53:13.142356Z 0 [Note] InnoDB: Setting file &#39;./ibtmp1&#39; size to 12 MB. Physically writing the file full; Please wait ...
    2020-01-21T07:53:13.184613Z 0 [Note] InnoDB: File &#39;./ibtmp1&#39; size is now 12 MB.
    2020-01-21T07:53:13.185628Z 0 [Note] InnoDB: 96 redo rollback segment(s) found. 96 redo rollback segment(s) are active.
    2020-01-21T07:53:13.185733Z 0 [Note] InnoDB: 32 non-redo rollback segment(s) are active.
    2020-01-21T07:53:13.186108Z 0 [Note] InnoDB: Waiting for purge to start
    2020-01-21T07:53:13.236391Z 0 [Note] InnoDB: 5.7.15 started; log sequence number 12146163
    2020-01-21T07:53:13.236828Z 0 [Note] Plugin &#39;FEDERATED&#39; is disabled.
    2020-01-21T07:53:13.237186Z 0 [Note] InnoDB: Loading buffer pool(s) from /var/lib/mysql/ib_buffer_pool
    2020-01-21T07:53:13.252074Z 0 [Warning] Failed to set up SSL because of the following SSL library error: SSL context is not usable without certificate and private key
    2020-01-21T07:53:13.252900Z 0 [Note] Server hostname (bind-address): &#39;*&#39;; port: 3306
    2020-01-21T07:53:13.253023Z 0 [Note] IPv6 is available.
    2020-01-21T07:53:13.253076Z 0 [Note]   - &#39;::&#39; resolves to &#39;::&#39;;
    2020-01-21T07:53:13.253184Z 0 [Note] Server socket created on IP: &#39;::&#39;.
    2020-01-21T07:53:13.269950Z 0 [Warning] &#39;db&#39; entry &#39;sys mysql.sys@localhost&#39; ignored in --skip-name-resolve mode.
    2020-01-21T07:53:13.270581Z 0 [Warning] &#39;proxies_priv&#39; entry &#39;@ root@localhost&#39; ignored in --skip-name-resolve mode.
    2020-01-21T07:53:13.277379Z 0 [Note] InnoDB: Buffer pool(s) load completed at 200121  7:53:13
    2020-01-21T07:53:13.295467Z 0 [Warning] &#39;tables_priv&#39; entry &#39;sys_config mysql.sys@localhost&#39; ignored in --skip-name-resolve mode.
    2020-01-21T07:53:13.367019Z 0 [Note] Event Scheduler: Loaded 0 events
    2020-01-21T07:53:13.368851Z 0 [Note] mysqld: ready for connections.
    Version: &#39;5.7.15&#39;  socket: &#39;/var/run/mysqld/mysqld.sock&#39;  port: 3306  MySQL Community Server (GPL)

Now entered in the container:

    docker exec -it 49419cb9980a bash
    
    root@49419cb9980a:/#

I have checked if MYSQL_ROOT_PASSWORD is set correctly(in the container):

    root@49419cb9980a:/# echo $MYSQL_ROOT_PASSWORD
    123

Then tried to log into mysql:

    root@49419cb9980a:/# mysql -u root -p
    Enter password:
    ERROR 1045 (28000): Access denied for user &#39;root&#39;@&#39;localhost&#39; (using password: YES)

My question is, how to solve this problem? Why can&#39;t I access mysql? I tried with no password option too. 
That gave me this error:

    mysql -u root
    ERROR 1045 (28000): Access denied for user &#39;root&#39;@&#39;localhost&#39; (using password: NO)

This is my project structure:

    tree
    .
    ├── db
    │&#160;&#160; ├── Dockerfile
    │&#160;&#160; └── database100.sql
    └── docker-compose.yml
    
    1 directory, 3 files



MYSQL_ROOT_PASSWORD is set but getting &quot;Access denied for user &#39;root&#39;@&#39;localhost&#39; (using password: YES)&quot; in docker container

When I run the command `docker run -i -t myProject` it shows error: 

&gt;  It was not possible to find any installed .NET Core SDKs
  Did you mean to run .NET Core SDK commands? Install a .NET Core SDK from:
      https://aka.ms/dotnet-download

However, I do have the .NET Core SDK installed and the `PATH` is correct (followed here: https://docs.microsoft.com/en-us/aspnet/core/test/troubleshoot?view=aspnetcore-3.1#no-net-core-sdks-were-detected). 

What&#39;s more, my project only needs runtime .NET Core SDK.

Does anyone know what might be the issue?

When running dotnet --info I got:

.NET Core SDK (reflecting any global.json):
 Version:   3.1.101
 Commit:    b377529961

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.18363
 OS Platform: Windows
 RID:         win10-x86
 Base Path:   C:\Program Files (x86)\dotnet\sdk\3.1.101\

Host (useful for support):
  Version: 3.1.1
  Commit:  a1388f194c

.NET Core SDKs installed:
  3.1.101 [C:\Program Files (x86)\dotnet\sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.App 3.1.0 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.1 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 3.1.0 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.1 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.0 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.1 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download

Error: It was not possible to find any installed .NET Core SDKs

I am trying to set up docker image of amazon ECR on ```ubuntu18.04``` machine of AWS,using commands provided by ```view push commands``` of ```Amazon Container Services```
[![view push commands of amazon container services][1]][1]

 ,please note i have already set up ```docker``` on my ```ubuntu18.04``` and also output of ```docker -v``` is as below

    ubuntu@ip-172-31-0-143:~$ docker -v
    Docker version 19.03.7, build 7141c199a2


  [1]: https://i.stack.imgur.com/x8w8O.png

When i execute the command provided by amazon container services on aws cli on ubuntu18.04 i get error as
    Error: Cannot perform an interactive login from a non TTY device

The command which i am using is 

    aws ecr get-login-password --region us-west-2 | docker login --username AWS --password-stdin 8233251134332.dkr.ecr.us-east-2.amazonaws.com/gatling-lots

please note i have successfully configured awscli and i can see the
detailed  from ```aws s3 ls```

Here is detailed error log
 
    ubuntu@ip-172-31-0-143:~$ aws ecr get-login-password --region us-   
    east-2 | docker login --username AWS --password-stdin 
    823443336.dkr.ecr.us-west-2.amazonaws.com/gatling-lots
    usage: aws [options] &lt;command&gt; &lt;subcommand&gt; [&lt;subcommand&gt; ...]      
    [parameters]
     To see help text, you can run:

    aws help
    aws &lt;command&gt; help
    aws &lt;command&gt; &lt;subcommand&gt; help
    aws: error: argument operation: Invalid choice, valid choices are:

     batch-check-layer-availability           | batch-delete-image                      
     batch-get-image                          | complete-layer-upload                   
    create-repository                        | delete-lifecycle-policy                 
    delete-repository                        | delete-repository-policy                
     describe-images                          | describe-repositories                   
     get-authorization-token                  | get-download-url-for-layer              
     get-lifecycle-policy                     | get-lifecycle-policy-preview            
     get-repository-policy                    | initiate-layer-upload                   
     list-images                              | put-image                               
     put-lifecycle-policy                     | set-repository-policy                   
     start-lifecycle-policy-preview           | upload-layer-part                       
     get-login                                | help                                    
     Error: Cannot perform an interactive login from a non TTY device

output of

    ubuntu@ip-172-31-0-143:~$ (aws ecr get-login --no-include-email  --region us-east-2)

    docker login -u AWS -p 
    
    MzQxL2c0Yks4RjVxeDg9IiwidmVyc2lvbiI6IjIiLCJ0eXBlIjoiREFUQV9LRVkiLCJleHBpcmF0aW9uIjoxNTgzNjgzNDY5fQ== https://825251119036.dkr.ecr.us- east-2.amazonaws.com

aws ecr saying &quot;Cannot perform an interactive login from a non TTY device&quot; after copied cmd from &quot;Amazon Container Services&quot;

I&#39;ve ran into an issue with Docker Desktop, currently im running the edge version as a user on Stackoverflow. Before I got the drive not shared for unknown reason error which was &quot;solved&quot; by installing edge version: https://stackoverflow.com/questions/59555010/docker-for-windows-drive-sharing-failed-for-an-unknown-reason

Now that this was installed im getting this new error which prevents some containers from being built. These containers have all been tested and works on several other systems. Currently 3 out of 4 containers are not built and they all produce the same error as below:

    ERROR: for db  Cannot create container for service db: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    Encountered errors while bringing up the project.


full error:

    Creating imt2291-part2_www_1 ...
    Creating imt2291-part2_phpmyadmin_1 ... done
    Creating imt2291-part2_db_1         ...
    Creating imt2291-part2_test_1       ... error
    Creating imt2291-part2_www_1        ... error
    ERROR: for imt2291-part2_test_1  Cannot create container for service test: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    
    ERROR: for imt2291-part2_www_1  Cannot create container for service www: status Creating imt2291-part2_db_1         ... error
    lled&quot;}
    
    ERROR: for imt2291-part2_db_1  Cannot create container for service db: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    
    ERROR: for test  Cannot create container for service test: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    
    ERROR: for www  Cannot create container for service www: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    
    ERROR: for db  Cannot create container for service db: status code not OK but 500: {&quot;Message&quot;:&quot;Unhandled exception: Filesharing has been cancelled&quot;}
    Encountered errors while bringing up the project.

Has anyone encountered this issue before and found a fix?


Docker Compose failed to build - Filesharing has been cancelled

After having read about the performance improvements when running Docker on wsl2, I have been waiting for the official release of Windows 10 that supports wsl2.
I updated Windows and Docker and switched on the Docker flag to use wsl2 and was hoping for some performance boost for my Oracle Database running in a Docker container but unfortunately the change slowed down the container and my laptop dramatically.
The performance of the container is about 10x slower and my laptop is pretty much stuck when starting the container.
It seems as if the memory consumption would completely use up my 8GB and heavy memory swapping starts to take place.
Is there anything I can do to improve the performance of Docker on wsl2 or at least to better understand what&#39;s wrong in my setup?

My environment:

* Processor Intel(R) Core(TM) i7-2620M CPU @ 2.70GHz, 2 Core(s)
* Installed Physical Memory (RAM)	8.00 GB
* Microsoft Windows 10 Pro Version 10.0.19041 Build 19041
* Docker version 19.03.8, build afacb8b


docker on wsl2 very slow

I was trying to build my Docker image for my [Gatsby][1] application. Whenever I run the command `docker build . -t gatsbyapp`, it gives me an error:

```
failed to solve with frontend dockerfile.v0: failed to build LLB:
failed to compute cache key: &quot;/.env&quot; not found: not found
```

Meanwhile my Dockerfile is shown below:

    FROM node:13

    WORKDIR /app

    COPY package.json .

    RUN yarn global add gatsby-cli

    RUN yarn install

    COPY gatsby-config.js .

    COPY .env .

    EXPOSE 8000

    CMD [&quot;gatsby&quot;,&quot;develop&quot;,&quot;-H&quot;,&quot;0.0.0.0&quot;]

  [1]: https://www.gatsbyjs.com/






An error, &quot;failed to solve with frontend dockerfile.v0&quot;

I am pretty new to Docker and trying to build docker image with plain html but i have this error message, saying
**failed to solve with frontend dockerfile.v0: failed to read dockerfile: open /var/lib/docker/tmp/buildkit-mount602954594/Dockerfile: no such file or directory**

My folder directory is like this
```
C:\Users\hailey\Desktop\GitTest
                               |- Dockerfile.txt
                               |- README.md
                               |- testHelloWorld.html

```

Inside of the Dockerfile, I have

```
FROM ubuntu  
WORKDIR C/Users/hailey/Desktop/GitTest
COPY testHelloWorld.html .
EXPOSE 8080
CMD [&quot;html&quot;,&quot;testHelloWorld.html&quot;]
```

I did my command docker build . inside of the directory C:\Users\hailey\Desktop\GitTest.
then got 
```
[+] Building 0.1s (2/2) FINISHED
 =&gt; [internal] load build definition from Dockerfile                                                                                                                           
 =&gt; =&gt; transferring dockerfile: 2B                                                                                                                                             
 =&gt; [internal] load .dockerignore                                                                                                                                              
 =&gt; =&gt; transferring context: 2B                                                                                                                                               
failed to solve with frontend dockerfile.v0: failed to read dockerfile: open /var/lib/docker/tmp/buildkit-mount602954594/Dockerfile: no such file or directory
```

Does anyone have any other what I did wrong?

failed to solve with frontend dockerfile

I&#39;ve a dockerfile as below, but during `RUN npm ci` step, there is a warning,

&gt; npm WARN old lockfile The package-lock.json file was created with an old version of npm

which I can not able to figure out..

I tried with npm install rather npm ci and added the `--package-lock` flag, but I am still getting this warning. It’s a kind of warning that I have to ignore it or what should I do to solve this?

```lang-none
Step 12/26 : RUN npm ci --production --package-lock &amp;&amp;     npm ci --production --package-lock --prefix ./ui-runner
 ---&gt; Running in 3473c209b98c
npm WARN old lockfile
npm WARN old lockfile The package-lock.json file was created with an old version of npm,
npm WARN old lockfile so supplemental metadata must be fetched from the registry.
npm WARN old lockfile
npm WARN old lockfile This is a one-time fix-up, please be patient...
npm WARN old lockfile
```

Here is my *Dockerfile*.

```lang-none
FROM node:14.17.1-alpine3.13 AS builder
WORKDIR /usr/src/app
COPY package.json package-lock.json* ./
COPY ui-runner/package*.json ./ui-runner/
COPY .npmrc .npmrc
COPY ui-runner/.npmrc ./ui-runner/.npmrc
RUN npm -g install npm@7.19.1
RUN npm ci --production --package-lock &amp;&amp; \
    npm ci --production --package-lock --prefix ./ui-runner
RUN rm -f .npmrc &amp;&amp; \
    rm -f ui-runner/.npmrc

FROM node:14.17.1-alpine3.13
WORKDIR /usr/src/app
RUN apk update &amp;&amp; apk add --no-cache curl bash
RUN addgroup -g 1001 test &amp;&amp; \
    adduser -S -u 1001 -G test test
RUN chown -R test /usr/src/app &amp;&amp; \
    chmod 755 /usr/src/app
COPY --from=builder /usr/src/app /usr/src/app
COPY . .
RUN npm run build:docker
USER test
EXPOSE 3000 9183
CMD [ &quot;npm&quot;, &quot;run&quot;, &quot;start:ui-runner&quot; ]
```





Content Type	Original Author	Original Content on Stackoverflow
Question	MayankBudhiraja	View Question on Stackoverflow
Solution 1 - Django	Zeitounator	View Answer on Stackoverflow
Solution 2 - Django	Shreeyansh Jain	View Answer on Stackoverflow

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