Linux gosu что это
Docker using gosu vs USER
Docker kind of always had a USER command to run a process as a specific user, but in general a lot of things had to run as ROOT.
I have seen a lot of images that use an ENTRYPOINT with gosu to de-elevate the process to run.
I know quite a bit has changed in terms of security with Docker 1.10, but I’m still not clear about the recommended way to run a process in a docker container.
3 Answers 3
Dockerfiles are for creating images. I see gosu as more useful as part of a container initialization when you can no longer change users between run commands in your Dockerfile.
After the image is created, something like gosu allows you to drop root permissions at the end of your entrypoint inside of a container. You may initially need root access to do some initialization steps (fixing uid’s, host mounted volume permissions, etc). Then once initialized, you run the final service without root privileges and as pid 1 to handle signals cleanly.
Edit: Here’s a simple example of using gosu in an image for docker and jenkins: https://github.com/bmitch3020/jenkins-docker
The entrypoint.sh looks up the gid of the /var/lib/docker.sock file and updates the gid of the docker user inside the container to match. This allows the image to be ported to other docker hosts where the gid on the host may differ. Changing the group requires root access inside the container. Had I used USER jenkins in the dockerfile, I would be stuck with the gid of the docker group as defined in the image which wouldn’t work if it doesn’t match that of the docker host it’s running on. But root access can be dropped when running the app which is where gosu comes in.
At the end of the script, the exec call prevents the shell from forking gosu, and instead it replaces pid 1 with that process. Gosu in turn does the same, switching the uid and then exec’ing the jenkins process so that it takes over as pid 1. This allows signals to be handled correctly which would otherwise be ignored by a shell as pid 1.
Внедрение GosLinux оказалось в 37 раз дешевле лицензий Windows
Скриншот: atmega644
Федеральная служба судебных приставов (ФССП) огласила смету расходов на установку свободной операционной системы GosLinux в подразделениях судебных приставов в 70 субъектах РФ. На сегодняшний день это самый успешный и широкомасштабный проект по миграции российских госструктур с Windows на Linux.
Итак, за 2013-2015 гг разработка, внедрение, сопровождение, сертификация, доработка и три инспекционных контроля обошлись в 19,155 млн руб (в том числе непосредственно разработка и сертификация — 5 млн руб). Ещё 2 млн руб потрачено на обучение администраторов. В результате, стоимость одной установленной версии GosLinux обошлась менее чем в 1500 руб.
Для сравнения, стоимость лицензионных программ Microsoft на такое же количество компьютеров составляет 794 млн руб, по оценке партнёров Microsoft.
Такие цифры назвала на рабочем совещании по вопросам импортозамещения замдиректора ФССП Татьяна Игнатьева.
«В настоящий момент GosLinux установлен на 16 тыс. рабочих мест и на 660 серверах службы. К концу года в связи с тем, что мы себе поставили задачу не только в виде деклараций и целей, но и зафиксировали решение на нашей годовой коллегии, мы собираемся довести показатель внедрения до 50%, снизив тем самым удельную стоимость одной версии примерно до 800 руб», — сказала Игнатьева.
В вышеприведённой оценке стоимости продуктов Microsoft рассчитана стоимость бессрочной лицензии на Windows Proffesional 8.1 + Microsoft Office Standart 2013 RUS OLP С Gov для всего объёма рабочих станций + пакет сертификации на каждый объект (2500 объектов) + лицензия на Windows Server Standard 2012R2 OLP A Gov 2Proc для 2500 серверов с пакетами сертификации.
GosLinux — свободная ОС на базе CentOS 6.4 (Red Hat Enterprise Linux). Разработчиком дистрибутива выступила компания «Ред софт», победившая в марте 2013 г. в конкурсе на доработку, внедрение и сопровождение подсистем АИС ФССП.
В прошлом году создан открытый репозиторий GosLinux, а 27 августа 2015 года систему приняли в Национальный фонд алгоритмов и программ. Таким образом, GosLinux стал первой сертифицированной операционной системой на базе свободного программного обеспечения, пригодной для использования во всех государственных органах, государственных внебюджетных фондах и органах местного самоуправления России.
Операционная система типового дистрибутива АИС ФССП России получила сертификат соответствия ФСТЭК России № 3119, подтверждающий, что операционная система типового дистрибутива имеет оценочный уровень доверия ОУД3 и соответствует требованиям по 4 уровню контроля отсутствия недекларированных возможностей.
GosLinux распространяется бесплатно. За последние 30 суток дистрибутив скачали 1061 раз, в том числе вчера — 84 раза.
Русские Блоги
Centos установить с помощью gosu
Что такое госу?
установка госу
Если вы действительно не можете открыть github, вы можете клонировать проект на github прямо на локальный:
Но приведенная выше информация основана на Debian и alpine, поэтому, если вы используете Debian, вы можете обратиться к нему напрямую.
Если вы используете другие дистрибутивы Linux, продолжайте читать: (я использую Centos)
В dockerhub я нашел образ Linux, интегрированный с gosu. Я щелкнул по нему и посмотрел. У меня возникли некоторые мысли.
gosu/assets с участием gosu/centos:tag Это то, что нам нужно.
2. Изменить 1. средний Dockerfile
ответит gosu Дистрибутив Linux Dockerfile Добавить контент в 1. В Dockerfile немного изменено:
Это просто демонстрация. Если вы хотите использовать пустой образ centos, вы можете загрузить и установить его прямо на dockerhub. В конце концов, иногда мы хотим добавить gosu в существующий образ, поэтому реальный процесс неизбежен.
Поскольку я написал 2 раздела сборки в Dockerfile, первый раздел не имеет имени метки. Здесь вы можете добавить метку вручную
Хорошо, после получения изображения попробуем запустить gosu, чтобы увидеть эффект.
В контейнер создайте test Directory, вы можете видеть, что по умолчанию владелец и группа являются root.
Когда мы хотим создать каталог с необычными пользователями в качестве владельца и группы под пользователем root, мы можем использовать gosu. Это действительно очень полезный инструмент:
Я заранее создал здесь обычного пользователя.
Getting Started
There are several options to get started with Gosu depending on your needs
Gosu Lab
Gosu Lab is the easiest way to experiment with Gosu:
You can try the bundled example projects like the Life game. Just select Life from the Examples pane and run the game by pressing F5.
Gosu Plugin for IntelliJ
The Gosu Plugin for IntelliJ is the recommended way to use Gosu. Keep in mind, however, the latest new language features may not yet be supported in the IntelliJ plugin. If this is the case and you want to experiment with new features, use the Gosu Lab IDE instead (see instructions above).
The plugin is hosted on the IntelliJ IDEA Plugin Repository and you can download it directly from within IntelliJ IDEA. If you installed the old 3.X plugin, delete the plugin and remove the Gosu SDK (File > Project Structure > SDKs), the new plugin does not need it.
Maven and Gradle
If Maven is your thing, here is a simple starter project. Run mvn test to execute the JUnit tests contained within.
. and More
Alternatively, a downloadable archive of simple command-line examples is available here. Check the README file for instructions or view the source.
For the truly impatient, you can evaluate some simple gosu expressions online over on the Play page.
The Basics
Variables and Type Declarations
Gosu is statically typed, but uses type inference to eliminate the vast majority of syntax overhead usually involved with static typing.
Operators
Gosu supports the standard Java operators, with a few minor restrictions and some great bonuses:
Loops
The Gosu for loop
The for loop in Gosu allows you to iterate over both arrays and anything that implements the java.lang.Iterable interface.
You can also get access to the zero-based index of the loop by including an index variable:
And, if you need access to the iterator for the loop (assuming you are looping over an Iterable ) you can use the iterator keyword:
Properties
Gosu properties are a way to abstract field access in Gosu classes.
Consider this standard Java boilerplate:
This is a verbose way to simply expose a field, but exposing the field directly has it’s own problems, which is where properties come in.
Here is the same class in Gosu:
If you want the property to be readonly, you can use the readonly modifier:
If you want to add some logic to the get or set of a propery, you can use this longer syntax:
Reading and writing properties works just like accessing a field:
Null Safety
Gosu offers a few helpful tricks to deal with null in your code.
Null Safe Method Invocation
Consider this code:
The null safe invocation operator works on both methods and properties.
The Elvis Operator
Classes
Here is a basic Gosu class:
The above code demonstrates the following features:
Named Arguments & Default Parameters
Gosu supports both named arguments and default parameter values, which can dramatically improve APIs.
And you could now invoke it like so:
Additionally, Gosu allows you to use a named argument syntax when you are working with non-overloaded methods on Gosu classes. You prefix the parameter name with a colon : like so:
Named arguments can be used to clarify code, so you don’t end up with things like this:
Superclasses, Interfaces and Delegates
Gosu classes can extend other classes and implement interfaces just like in Java, using the extends and implements keywords respectively.
One interesting additional feature of Gosu is the ability to delegate the implementation of an interface to a class variable using the delegate and represents keywords:
Note that the class MyRunnable does not declare a run() method, as Runnable requires. Rather, it uses the delegate field _runnable to implement the interface:
Delegates give you a convenient way to favor composition over inheritance.
The Using Statement
The using statement allows you to wrap sections of code that require connections to be closed to be handled automatically when the block finishes. Instead of writing code like this:
In Gosu, you can use the using statement which will handle closing the Connection for you:
The using statement works with the following interfaces:
Gosu Program Files
Here is a simple Hello World application, in the file hello.gsp:
Running the program is simple:
Classpath Statements, Program Extends & Shebang
Gosu programs can embed a classpath in their source, obviating the need for users to pass in a correct classpath externally:
The classpath statement is comma delimited, to avoid system specific dependencies. Each path on it will be added to the classpath. If a path points at a folder and that folder contains jars, all those jars will be added to the classpath as well.
The classpath can also include Maven coordinates, and Gosu will automatically resolve and download them at runtime:
Gosu supports the Unix shebang standard, so your program can begin with #! gosu and Unix-like shells will execute the script with gosu. This makes it much more pleasant to run gosu programs:
No wrapping scripts, no complicated class paths.
Finally, you can set the superclass for a program using the extends keyword:
This allows you to access methods and features in the parent class within your program, and can be used to create simple Gosu-based scripting tools.
Blocks
Blocks (also called closures or lambda expressions) are a simple way to specify an inline function. They have a lot of uses, but they really shine in data structure manipulation:
You can think of it as an inline version of this function:
Blocks allow you to express your logic much more succinctly.
With blocks you can dramatically reduce the amount of code you write when compared with Java.
Consider this complicated Java code:
This can be rewritten in Gosu as:
The Gosu code is clearer and far more brief.
Blocks and Interfaces
Java has many interfaces that contain a single method, which are used as a stand-in for actual closures. In order to facilitate Java interoperability, Gosu blocks and one-method interfaces are automatically converted between one another:
This makes some Java APIs much more pleasant to work with in Gosu.
Enhancements
Enhancements provide a way to add methods and properties to existing types. They are similar to Extension Methods in C#, but do not need to be explicitly imported.
In enhancements, the this symbol refers to the enhanced type, as opposed to the enhancement itself.
Once an enhancement has been added to your classpath, you can use it in any place you have an object of the enhanced type with no need to explicitly import the enhancement itself. Therefore, using the enhancement above is as simple as just calling the new function anywhere you have a String:
Semantics And Limitations
The above code can be thought of as shorthand for this code:
Enhancements are statically dispatched. This means they cannot be used to implement interfaces or to achieve polymorphism
Generics
Enhancements can be generic, so you can add an enhancement to List :
This method will now be available on all generic lists, and will be properly typed.
Type Variable Reification
Unlike in Java, type variables can be used in general expressions in Gosu. In Enhancements, the type variables are statically, rather than dynamically, reified, much like enhancement methods are statically, rather than dynamically dispatched. The enhancement method toTypedArray():T[] on Iterable demonstrates this:
This «best effort» reification usually does what you want, but can occasionally lead to surprising results.
Enhancing Parameterized Types
A really neat trick with enhancements is that you can enhance parameterized types:
This is how all lists of comparable objects have the sort() method on them, while other lists do not.
Strings & Gosu Templates
String literals in Gosu can be expressed using either double or single quotes:
Strings support concatenation:
Because Strings are so common, there are also a bunch of handy enhancements which allows for easy conversion from strings to other types:
Here is a short sample of additional enhancements on String :
Gosu Template Files (.gst)
Here is an example definition, sample.SampleTemplate.gst :
The template explicitly declares the names and types of its arguments using the params() directive
You can render a template by calling the render(w:Writer) or renderToString() static methods:
For each parameter defined in the params directive, an additional argument with that name and type is added to the render() and renderToString() methods.
So, given the template definition above, you could render it like so:
Using templates gives you a type safe way to generate large strings in your applications.
Collections In Gosu
List & Map Syntax
java.util.List and java.util.Map are the two most commonly used data structures in Java. Unfortunately, they can also be fairly verbose to deal with in Java:
Luckily Gosu provides a shorthand syntax for these two types, allowing the above code to simply be written as:
Enhancements
Gosu adds a whole slew of enhancements to collections classes. Here are some of the most useful ones for java.lang.Iterable :
Enhancement | Description |
---|---|
allMatch( cond(elt1 : T):boolean ) : boolean | Returns true if all elements in this collection match the given condition and false otherwise |
average( select:block(elt:T):java.lang.Number ) : BigDecimal | Return the average of the mapped value |
concat( that : Collection ) : Collection | Return a new list that is the concatenation of the two lists |
Count() : int | Return the number of elements in this Iterable object |
countWhere( cond(elt:T):boolean ) : int | Return the count of elements in this collection that match the given condition |
disjunction( that : Collection ) : Set | Returns a the set disjunction of this collection and the other collection, that is, all elements that are in one collection not and not the other |
each( operation(elt : T) ) | This method will invoke the operation on each element in the Collection |
eachWithIndex( operation(elt : T, index : int ) ) | This method will invoke the operation on each element in the Collection, passing in the index as well as the element |
first() : T | Returns the first element in this collection. If the collection is empty, null is returned |
firstWhere( cond(elt:T):boolean ) : T | Returns the first element in this collection that matches the given condition. If no element matches the criteria, null is returned |
fold( aggregator(elt1 : T, elt2 : T):T ) : T | Returns all the values of this collection folded into a single value |
hasMatch( cond(elt1 : T):boolean ) : boolean | Returns true if any elements in this collection match the given condition and false otherwise |
intersect( that : Collection ) : Set | Return the set intersection of these two collections |
join( delimiter : String ) : String | Coerces each element in the collecion to a string and joins them together with the given delimiter |
last() : T | Returns the last element in this collection. If the collection is empty, null is returned |
lastWhere( cond(elt:T):boolean ) : T | Returns the last element in this collection that matches the given condition. If the collection is empty, null is returned |
map ( mapper(elt : T):Q ) : List | Maps the values of the collection to a list of values by calling the mapper block on each element |
maxBy( comparison(elt : T):Comparable ) : T | Returns the maximum value of this collection with respect to the Comparable attribute calculated by the given block. If more than one element has the maximum value, the first element encountered is returned |
max ( transform(elt:T):R ) : R | Returns the maximum value of the transformed elements |
minBy( comparison(elt : T):Comparable ) : T | Returns the minimum value of this collection with respect to the Comparable attribute calculated by the given block. If more than one element has the minimum value, the first element encountered is returned |
min ( transform(elt:T):R ) : R | Returns the minimum value of the transformed elements |
partitionUniquely ( mapper(elt : T):Q ) : Map | Partitions each element into a Map where the keys are the value produce by the mapper block and the values are the elements of the Collection. If two elements map to the same key an IllegalStateException is thrown |
orderBy ( value(elt:T):R ) : IOrderedList | Returns a lazily-computed List that consists of the elements of this Collection, ordered by the value mapped to by the given block |
orderByDescending ( value(elt:T):R ) : IOrderedList | Returns a lazily-computed List that consists of the elements of this Collection, descendingly ordered by the value mapped to by the given block |
reduce ( init : V, aggregator(val : V, elt2 : T):V ) : V | Returns all the values of this collection down to a single value |
removeWhere( cond(elt:T):boolean ) | Removes all elements that match the given condition in this collection |
retainWhere( cond(elt:T):boolean ) | Retains all elements that match the given condition in this collection |
reverse() : List | Returns a new list of the elements in the collection, in their reverse iteration order |
single() : T | Returns a single element from this iterable, if only one exists. It no elements are in this iterable, or if there are more than one elements in it, an IllegalStateException is thrown |
singleWhere( cond(elt:T):boolean ) : T | Returns a single item matching the given condition. If there is no such element or if multiple elements match the condition, and IllegalStateException is thrown |
subtract( that : Collection ) : Set | Returns the Set subtraction of that Collection from this Collection |
toCollection() : Collection | If this Iterable is already a Collection, return this Itearble cast to a Collection. Otherwise create a new Collection and copy this Iterable into it |
toList() : List | If this Iterable is already a List, return this Iterable cast to a List. Otherwise create a new List and copy this Iterable into it |
toSet() : Set | If this Iterable is already a Set, return this Iterable cast to a Set. Otherwise create a new Set based on this Iterable |
toTypedArray() : T[] | Returns a strongly-typed array of this Iterable, as opposed to the argumentless Iterable#toArray(), which returns an Object array. This method takes advantage of static reification and, therefore, does not necessarily return an array that matches the theoretical runtime type of the Iterable, if actual reification were supported |
union( that : Collection ) : Set | Returns the set union of the two collections |
where( cond(elt:T): boolean ) : List | Returns all the elements of this collection for which the given condition is true |
whereTypeIs ( type : Type ) : List | Returns all the elements of this collection that are assignable to the given type |
zip ( other : Iterable ) : List > | Returns a list of gw.util.Pair s of elements from matching indices of this and the other Iterables. If one Iterable contains more elements than the other then only return a list of the same length as the shortest of the two Iterables. |
Enjoy!
That’s a good overview of what the Gosu language provides for you. Please give it a try and, if you have any questions, hit us up on the Newsgroup!
СОДЕРЖАНИЕ
История
Guidewire продолжает поддерживать и широко использовать Gosu в приложениях InsuranceSuite. На данный момент Guidewire решила приостановить разработку новых конструкций языка программирования Gosu. Guidewire продолжает развивать InsuranceSuite с помощью API-интерфейсов RESTful и платформ интеграции, к которым можно получить доступ с помощью Java.
Философия
Синтаксис и семантика
Gosu поддерживает несколько типов файлов:
В дополнение к стандартным типам классов Gosu поддерживает перечисления, интерфейсы, структуры и аннотации.
Программные файлы упрощают использование Gosu как языка сценариев. Например, Hello, World! это простая однострочная программа:
Классы Gosu также исполняются а-ля Java:
Типы данных
Уникальной особенностью Gosu является его система открытых типов, которая позволяет легко расширять язык для обеспечения проверки во время компиляции и осведомленности IDE об информации, которая обычно проверяется только во время выполнения на большинстве других языков. Усовершенствования позволяют добавлять дополнительные функции и свойства к другим типам, включая встроенные типы Java, такие как String, List и т. Д. В этом примере демонстрируется добавление функции print () к java.lang.String.
Теперь вы можете указать String печатать саму себя:
Комбинация закрытий и улучшений обеспечивает мощный способ кодирования с помощью коллекций. Накладные расходы на потоки Java не нужны с Gosu: