Tutorial by Examples: l

1. Logs: By default, Heroku allows only 1500 lines of consolidated logs. When more than 1500 lines of logs are required, one has to use addons provided Heroku. 2. Router: HTTP request have 30s timeout for initial response and 55s timeout thereafter. Maximum of 1MB buffer allowed for response. 3....

To use the value stored in a variable, use the dollar sign followed by the variable name enclosed by parentheses or curly braces. x = hello y = $(x) # y now contains the value "hello" y = ${x} # parentheses and curly braces are treated exactly the same If a variable's name is only ...

Simply-expanded variables behave like variables from traditional programming languages. The expression on the right-hand side is evaluated, and the result is stored in the variable. If the right-hand side contains a variable reference, that variable is expanded before the assignment takes place. ...

When defining a recursively-expanded variable, the contents of the right-hand side are stored as-is. If a variable reference is present, the reference itself is stored (not the value of the variable). Make waits to expand the variable references until the variable is actually used. x = hello y =...

Within the context of an individual rule, Make automatically defines a number of special variables. These variables can have a different value for each rule in a makefile and are designed to make writing rules simpler. These variables can only be used in the recipe portion of a rule. VariableDesc...

The ?= operator is an extension that behaves like =, except that the assignment only occurs if the variable is not already set. x = hello x ?= world # $(x) will yield "hello"

The += operator is a common extension that adds the specified content to the end of the variable, separated by a space. x = hello x += world Variable references in the right-hand side will be expanded if and only if the original variable was defined as a simply-expanded variable.

Helpers and fakeApplication Class Helpers is used a lot for unit tests. It imitates a Play application, fakes HTTP requests and responses, session, cookies - all whatever may be needed for tests. A controller under the test should be executed in a context of a Play application. The Helpers method f...

This is such a common requirement in iOS development, and it was always something that had to be done purely in code (or using images - yuck!). Now it's incredibly easy to preview his kind of thing in Interface Builder, there's absolutely no excuse for not using it. Here's the code:- import UIKit ...

File Structure: pom.xml src/test/java/PlayStoreAutomation.java Launch command: mvn test -Dtest=PlayStoreAutomation PlayStoreAutomation.java import org.junit.AfterClass; import org.junit.BeforeClass; import org.junit.Test; import io.appium.java_client.android.AndroidDriver; import i...

The below example widget demonstrates how to format individual cells of a TreeView column conditionally, depending on value of the field in the particular cell. If value of field is negative, then it'll be displayed in red color and minus symbol will be hidden, otherwise it'll be displayed in normal...

The sequence for an error is usually: error is triggered by looking up the error name in errordict and executing this procedure. the errordict procedure calls signalerror, passing it the error name. signalerror takes snapshots of the stacks, saving the snapshots in $error, and then calls stop. ...

Most of the tools are standardized with the exception of the name of the operator to throw an error. In Adobe interpreters, it is called .error. In ghostscript, it is called signalerror. So with this line you can use signalerror in postscript code for Adobe interpreters or ghostscript or xpost. /.e...

The documentation for docker events provides details, but when debugging it may be useful to launch a container and be notified immediately of any related event: docker run... & docker events --filter 'container=$(docker ps -lq)' In docker ps -lq, the l stands for last, and the q for quiet. Th...

TextFile is the default file format, unless the configuration parameter hive.default.fileformat has a different setting. We can create a table on hive using the field names in our delimited text file. Lets say for example, our csv file contains three fields (id, name, salary) and we want to create ...

Tests are an excellent way to ensure stable, bug-free applications. They serve as an interactive documentation and allow to modify code without fear to break functionality. D provides a convenient and native syntax for unittest block as part of the D language. Anywhere in a D module unittest blocks ...

In the scenario that a controller throws an exception, we can define exception handler methods to build and return specific responses. It is important to note that the defined exception handlers within the given controller will only apply to exceptions that occur within that controller. @Controller...

We're going to build an application that stores POJOs in a database. The application uses Spring Data JPA to store and retrieve data in a relational database. Its most compelling feature is the ability to create repository implementations automatically, at runtime, from a repository interface. Main...

We add three records to our collection test as: > db.test.insert({"key":"value1","key2":"Val2","key3":"val3"}) WriteResult({ "nInserted" : 1 }) > db.test.insert({"key":"value2","key2":"V...

Defining the list of Ints trait IntList { ... } class Cons(val head: Int, val tail: IntList) extends IntList { ... } class Nil extends IntList { ... } but what if we need to define the list of Boolean, Double etc? Defining generic list trait List[T] { def isEmpty: Boolean def head:...