Spring Cloud Function is a project with the following high-level goals:
* Promote the implementation of business logic via functions.
* Decouple the development lifecycle of business logic from any specific runtime target so that the same code can run as a web endpoint, a stream processor, or a task.
* Support a uniform programming model across serverless providers, as well as the ability to run standalone (locally or in a PaaS).
* Enable Spring Boot features (auto-configuration, dependency injection, metrics) on serverless providers.
It abstracts away all of the transport details and
infrastructure, allowing the developer to keep all the familiar tools
and processes, and focus firmly on business logic.
Here's a complete, executable, testable Spring Boot application
(implementing a simple string manipulation):
[source,java]
----
@SpringBootApplication
public class Application {
@Bean
public Function<String, String> uppercase() {
return value -> value.toUpperCase();
}
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
----
It's just a Spring Boot application, so it can be built, run and
tested, locally and in a CI build, the same way as any other Spring
Boot application. The `Function` is from `java.util` and `Flux` is a
https://www.reactive-streams.org/[Reactive Streams] `Publisher` from
https://projectreactor.io/[Project Reactor]. The function can be
accessed over HTTP or messaging.
Spring Cloud Function has the following features:
* _Choice of programming styles - reactive, imperative or hybrid._
* _Function composition and adaptation (e.g., composing imperative functions with reactive)._
* _Support for reactive function with multiple inputs and outputs allowing merging, joining and other complex streaming operation to be handled by functions._
* _Transparent type conversion of inputs and outputs._
* _Packaging functions for deployments, specific to the target platform (e.g., Project Riff, AWS Lambda and more)_
* _Adapters to expose function to the outside world as HTTP endpoints etc._
* _Deploying a JAR file containing such an application context with an isolated classloader, so that you can pack them together in a single JVM._
* _Adapters for https://github.com/spring-cloud/spring-cloud-function/tree/master/spring-cloud-function-adapters/spring-cloud-function-adapter-aws[AWS Lambda], https://github.com/spring-cloud/spring-cloud-function/tree/master/spring-cloud-function-adapters/spring-cloud-function-adapter-azure[Azure], https://github.com/spring-cloud/spring-cloud-function/tree/master/spring-cloud-function-adapters/spring-cloud-function-adapter-gcp[Google Cloud Functions], and possibly other "serverless" service providers._
== Getting Started
Build from the command line (and "install" the samples):
Signing the contributor's agreement does not grant anyone commit rights to the main
@@ -195,19 +41,21 @@ repository, but it does mean that we can accept your contributions, and you will
author credit if we do. Active contributors might be asked to join the core team, and
given the ability to merge pull requests.
=== Codeof Conduct
This project adheres to the Contributor Covenant https://github.com/spring-cloud/spring-cloud-build/blob/master/docs/src/main/asciidoc/code-of-conduct.adoc[code of
[[code-of-conduct]]
== Code of Conduct
This project adheres to the Contributor Covenant https://github.com/spring-cloud/spring-cloud-build/blob/main/docs/src/main/asciidoc/code-of-conduct.adoc[code of
conduct]. By participating, you are expected to uphold this code. Please report
unacceptable behavior to spring-code-of-conduct@pivotal.io.
=== Code Conventionsand Housekeeping
[[code-conventions-and-housekeeping]]
== Code Conventions and Housekeeping
None of these is essential for a pull request, but they will all help. They can also be
added after the original pull request but before a merge.
* Use the Spring Framework code format conventions. If you use Eclipse
@@ -220,13 +68,14 @@ added after the original pull request but before a merge.
than cosmetic changes).
* Add some Javadocs and, if you change the namespace, some XSD doc elements.
* A few unit tests would help a lot as well -- someone has to do it.
* If no-one else is using your branch, please rebase it against the current master (or
* If no-one else is using your branch, please rebase it against the current main (or
other target branch in the main project).
* When writing a commit message please follow https://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html[these conventions],
if you are fixing an existing issue please add `Fixes gh-XXXX` at the end of the commit
message (where XXXX is the issue number).
=== Checkstyle
[[checkstyle]]
== Checkstyle
Spring Cloud Build comes with a set of checkstyle rules. You can find them in the `spring-cloud-build-tools` module. The most notable files under the module are:
@@ -244,7 +93,8 @@ Spring Cloud Build comes with a set of checkstyle rules. You can find them in th
<2> File header setup
<3> Default suppression rules
==== Checkstyleconfiguration
[[checkstyle-configuration]]
=== Checkstyle configuration
Checkstyle rules are *disabled by default*. To add checkstyle to your project just define the following properties and plugins.
@@ -303,16 +153,18 @@ If you need to suppress some rules (e.g. line length needs to be longer), then i
It's advisable to copy the `${spring-cloud-build.rootFolder}/.editorconfig` and `${spring-cloud-build.rootFolder}/.springformat` to your project. That way, some default formatting rules will be applied. You can do so by running this script:
In order to setup Intellij you should import our coding conventions, inspection profiles and set up the checkstyle plugin.
The following files can be found in the https://github.com/spring-cloud/spring-cloud-build/tree/master/spring-cloud-build-tools[Spring Cloud Build] project.
The following files can be found in the https://github.com/spring-cloud/spring-cloud-build/tree/main/spring-cloud-build-tools[Spring Cloud Build] project.
.spring-cloud-build-tools/
----
@@ -335,13 +187,13 @@ The following files can be found in the https://github.com/spring-cloud/spring-c
Go to `File` -> `Settings` -> `Editor` -> `Code style`. There click on the icon next to the `Scheme` section. There, click on the `Import Scheme` value and pick the `Intellij IDEA code style XML` option. Import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Spring_Boot_Java_Conventions.xml` file.
Go to `File` -> `Settings` -> `Editor` -> `Inspections`. There click on the icon next to the `Profile` section. There, click on the `Import Profile` and import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Project_Defaults.xml` file.
@@ -349,21 +201,268 @@ Go to `File` -> `Settings` -> `Editor` -> `Inspections`. There click on the icon
To have Intellij work with Checkstyle, you have to install the `Checkstyle` plugin. It's advisable to also install the `Assertions2Assertj` to automatically convert the JUnit assertions
Go to `File` -> `Settings` -> `Other settings` -> `Checkstyle`. There click on the `+` icon in the `Configuration file` section. There, you'll have to define where the checkstyle rules should be picked from. In the image above, we've picked the rules from the cloned Spring Cloud Build repository. However, you can point to the Spring Cloud Build's GitHub repository (e.g. for the `checkstyle.xml` : `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/main/resources/checkstyle.xml`). We need to provide the following variables:
Go to `File` -> `Settings` -> `Other settings` -> `Checkstyle`. There click on the `+` icon in the `Configuration file` section. There, you'll have to define where the checkstyle rules should be picked from. In the image above, we've picked the rules from the cloned Spring Cloud Build repository. However, you can point to the Spring Cloud Build's GitHub repository (e.g. for the `checkstyle.xml` : `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/main/resources/checkstyle.xml`). We need to provide the following variables:
- `checkstyle.header.file` - please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` URL.
- `checkstyle.suppressions.file` - default suppressions. Please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/master/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` URL.
- `checkstyle.header.file` - please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` URL.
- `checkstyle.suppressions.file` - default suppressions. Please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` URL.
- `checkstyle.additional.suppressions.file` - this variable corresponds to suppressions in your local project. E.g. you're working on `spring-cloud-contract`. Then point to the `project-root/src/checkstyle/checkstyle-suppressions.xml` folder. Example for `spring-cloud-contract` would be: `/home/username/spring-cloud-contract/src/checkstyle/checkstyle-suppressions.xml`.
IMPORTANT: Remember to set the `Scan Scope` to `All sources` since we apply checkstyle rules for production and test sources.
=== Duplicate Finder
[[duplicate-finder]]
== Duplicate Finder
Spring Cloud Build brings along the `basepom:duplicate-finder-maven-plugin`, that enables flagging duplicate and conflicting classes and resources on the java classpath.
==== Duplicate Finderconfiguration
[[duplicate-finder-configuration]]
=== Duplicate Finder configuration
Duplicate finder is *enabled by default* and will run in the `verify` phase of your Maven build, but it will only take effect in your project if you add the `duplicate-finder-maven-plugin` to the `build` section of the projecst's `pom.xml`.
For other properties, we have set defaults as listed in the https://github.com/basepom/duplicate-finder-maven-plugin/wiki[plugin documentation].
You can easily override them but setting the value of the selected property prefixed with `duplicate-finder-maven-plugin`. For example, set `duplicate-finder-maven-plugin.skip` to `true` in order to skip duplicates check in your build.
If you need to add `ignoredClassPatterns` or `ignoredResourcePatterns` to your setup, make sure to add them in the plugin configuration section of your project:
Signing the contributor's agreement does not grant anyone commit rights to the main
repository, but it does mean that we can accept your contributions, and you will get an
author credit if we do. Active contributors might be asked to join the core team, and
given the ability to merge pull requests.
[[code-of-conduct]]
== Code of Conduct
This project adheres to the Contributor Covenant https://github.com/spring-cloud/spring-cloud-build/blob/main/docs/src/main/asciidoc/code-of-conduct.adoc[code of
conduct]. By participating, you are expected to uphold this code. Please report
unacceptable behavior to spring-code-of-conduct@pivotal.io.
[[code-conventions-and-housekeeping]]
== Code Conventions and Housekeeping
None of these is essential for a pull request, but they will all help. They can also be
added after the original pull request but before a merge.
* Use the Spring Framework code format conventions. If you use Eclipse
* Make sure all new `.java` files to have a simple Javadoc class comment with at least an
`@author` tag identifying you, and preferably at least a paragraph on what the class is
for.
* Add the ASF license header comment to all new `.java` files (copy from existing files
in the project)
* Add yourself as an `@author` to the .java files that you modify substantially (more
than cosmetic changes).
* Add some Javadocs and, if you change the namespace, some XSD doc elements.
* A few unit tests would help a lot as well -- someone has to do it.
* If no-one else is using your branch, please rebase it against the current main (or
other target branch in the main project).
* When writing a commit message please follow https://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html[these conventions],
if you are fixing an existing issue please add `Fixes gh-XXXX` at the end of the commit
message (where XXXX is the issue number).
[[checkstyle]]
== Checkstyle
Spring Cloud Build comes with a set of checkstyle rules. You can find them in the `spring-cloud-build-tools` module. The most notable files under the module are:
.spring-cloud-build-tools/
----
└── src
├── checkstyle
│ └── checkstyle-suppressions.xml <3>
└── main
└── resources
├── checkstyle-header.txt <2>
└── checkstyle.xml <1>
----
<1> Default Checkstyle rules
<2> File header setup
<3> Default suppression rules
[[checkstyle-configuration]]
=== Checkstyle configuration
Checkstyle rules are *disabled by default*. To add checkstyle to your project just define the following properties and plugins.
<4> Add the Spring Java Format plugin that will reformat your code to pass most of the Checkstyle formatting rules
<5> Add checkstyle plugin to your build and reporting phases
If you need to suppress some rules (e.g. line length needs to be longer), then it's enough for you to define a file under `${project.root}/src/checkstyle/checkstyle-suppressions.xml` with your suppressions. Example:
It's advisable to copy the `${spring-cloud-build.rootFolder}/.editorconfig` and `${spring-cloud-build.rootFolder}/.springformat` to your project. That way, some default formatting rules will be applied. You can do so by running this script:
In order to setup Intellij you should import our coding conventions, inspection profiles and set up the checkstyle plugin.
The following files can be found in the https://github.com/spring-cloud/spring-cloud-build/tree/main/spring-cloud-build-tools[Spring Cloud Build] project.
.spring-cloud-build-tools/
----
└── src
├── checkstyle
│ └── checkstyle-suppressions.xml <3>
└── main
└── resources
├── checkstyle-header.txt <2>
├── checkstyle.xml <1>
└── intellij
├── Intellij_Project_Defaults.xml <4>
└── Intellij_Spring_Boot_Java_Conventions.xml <5>
----
<1> Default Checkstyle rules
<2> File header setup
<3> Default suppression rules
<4> Project defaults for Intellij that apply most of Checkstyle rules
<5> Project style conventions for Intellij that apply most of Checkstyle rules
.Code style
image::intellij-code-style.png[Code style]
Go to `File` -> `Settings` -> `Editor` -> `Code style`. There click on the icon next to the `Scheme` section. There, click on the `Import Scheme` value and pick the `Intellij IDEA code style XML` option. Import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Spring_Boot_Java_Conventions.xml` file.
.Inspection profiles
image::intellij-inspections.png[Code style]
Go to `File` -> `Settings` -> `Editor` -> `Inspections`. There click on the icon next to the `Profile` section. There, click on the `Import Profile` and import the `spring-cloud-build-tools/src/main/resources/intellij/Intellij_Project_Defaults.xml` file.
.Checkstyle
To have Intellij work with Checkstyle, you have to install the `Checkstyle` plugin. It's advisable to also install the `Assertions2Assertj` to automatically convert the JUnit assertions
image::intellij-checkstyle.png[Checkstyle]
Go to `File` -> `Settings` -> `Other settings` -> `Checkstyle`. There click on the `+` icon in the `Configuration file` section. There, you'll have to define where the checkstyle rules should be picked from. In the image above, we've picked the rules from the cloned Spring Cloud Build repository. However, you can point to the Spring Cloud Build's GitHub repository (e.g. for the `checkstyle.xml` : `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/main/resources/checkstyle.xml`). We need to provide the following variables:
- `checkstyle.header.file` - please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/main/resources/checkstyle-header.txt` URL.
- `checkstyle.suppressions.file` - default suppressions. Please point it to the Spring Cloud Build's, `spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` file either in your cloned repo or via the `https://raw.githubusercontent.com/spring-cloud/spring-cloud-build/main/spring-cloud-build-tools/src/checkstyle/checkstyle-suppressions.xml` URL.
- `checkstyle.additional.suppressions.file` - this variable corresponds to suppressions in your local project. E.g. you're working on `spring-cloud-contract`. Then point to the `project-root/src/checkstyle/checkstyle-suppressions.xml` folder. Example for `spring-cloud-contract` would be: `/home/username/spring-cloud-contract/src/checkstyle/checkstyle-suppressions.xml`.
IMPORTANT: Remember to set the `Scan Scope` to `All sources` since we apply checkstyle rules for production and test sources.
[[duplicate-finder]]
== Duplicate Finder
Spring Cloud Build brings along the `basepom:duplicate-finder-maven-plugin`, that enables flagging duplicate and conflicting classes and resources on the java classpath.
[[duplicate-finder-configuration]]
=== Duplicate Finder configuration
Duplicate finder is *enabled by default* and will run in the `verify` phase of your Maven build, but it will only take effect in your project if you add the `duplicate-finder-maven-plugin` to the `build` section of the projecst's `pom.xml`.
@@ -259,7 +259,7 @@ You can use the Spring Boot Maven Plugin to generate the <<thin-jar>>.
----
You can find the entire sample `pom.xml` file for deploying Spring Cloud Function
applications to AWS Lambda with Maven https://github.com/spring-cloud/spring-cloud-function/blob/{branch}/spring-cloud-function-samples/function-sample-aws/pom.xml[here].
applications to AWS Lambda with Maven https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-samples/function-sample-aws/pom.xml[here].
You can find the entire sample `build.gradle` file for deploying Spring Cloud Function
applications to AWS Lambda with Gradle https://github.com/spring-cloud/spring-cloud-function/blob/{branch}/spring-cloud-function-samples/function-sample-aws/build.gradle[here].
applications to AWS Lambda with Gradle https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-samples/function-sample-aws/build.gradle[here].
For, pure, Web-based function applications, you can replace the generic `adapter-azure` with the specialized https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-adapters/spring-cloud-function-adapter-azure-web[spring-cloud-function-adapter-azure-web].
The Azure Web Adapter can deploy any Spring Web application as a native Azure function, using the HttpTrigger internally.
@@ -414,7 +418,7 @@ For further information, explore the following, Azure Web Adapter, sample:
- https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-samples/function-sample-azure-web[ Azure Web Adapter (Maven)].
[[azure.usage]]
= Usage
== Usage
Common instructions for building and deploying both, `Azure Adapter` and `Azure Web Adapter` type of applications.
// If you want to debug your functions, please add the following line
@@ -551,14 +558,14 @@ Here is snippet for a `VSCode` remote debugging configuration:
----
[[functioninvoker-deprecated]]
= FunctionInvoker (deprecated)
== FunctionInvoker (deprecated)
WARNING: The legacy `FunctionInvoker` programming model is deprecated and will not be supported going forward.
For additional documentation and samples about the Function Integration approach follow the https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-samples/function-sample-azure/[azure-sample] README and code.
[[relevant-links]]
= Relevant Links
== Relevant Links
- https://learn.microsoft.com/en-us/azure/developer/java/spring-framework/getting-started-with-spring-cloud-function-in-azure[Spring Cloud Function in Azure]
- https://spring.io/blog/2023/02/24/spring-cloud-function-for-azure-function[Spring Cloud Function for Azure Function (blog)]
@@ -5,7 +5,7 @@ The Google Cloud Functions adapter enables Spring Cloud Function apps to run on
You can either run the function locally using the open source https://github.com/GoogleCloudPlatform/functions-framework-java[Google Functions Framework for Java] or on GCP.
[[project-dependencies]]
=== Project Dependencies
== Project Dependencies
Start by adding the `spring-cloud-function-adapter-gcp` dependency to your project.
@@ -63,12 +63,12 @@ NOTE: The function target should always be set to `org.springframework.cloud.fun
A full example of a working `pom.xml` can be found in the https://github.com/spring-cloud/spring-cloud-function/blob/master/spring-cloud-function-samples/function-sample-gcp-http/pom.xml[Spring Cloud Functions GCP sample].
[[http-functions]]
=== HTTP Functions
== HTTP Functions
Google Cloud Functions supports deploying https://cloud.google.com/functions/docs/writing/http[HTTP Functions], which are functions that are invoked by HTTP request. The sections below describe instructions for deploying a Spring Cloud Function as an HTTP Function.
[[getting-started]]
=== Getting Started
== Getting Started
Let’s start with a simple Spring Cloud Function example:
@@ -108,8 +108,8 @@ Invoke the HTTP function:
curl http://localhost:8080/ -d "hello"
----
[[deploy-to-gcp]]
=== Deploy to GCP
== Buikd & Deploy to GCP
Start by packaging your application.
@@ -171,8 +171,8 @@ The `spring-cloud-function-adapter-gcp` allows for functions to be deployed as b
The sections below describe the process for writing a Cloud Pub/Sub topic background function.
However, there are a number of different event types that can trigger a background function to execute which are not discussed here; these are described in the https://cloud.google.com/functions/docs/calling[Background Function triggers documentation].
[[getting-started]]
=== Getting Started
== GCP Getting Started
Let’s start with a simple Spring Cloud Function which will run as a GCF background function:
Lambda], and https://github.com/spring-cloud/spring-cloud-function/tree/{branch}/spring-cloud-function-adapters/spring-cloud-function-adapter-azure[Azure].
Lambda], and https://github.com/spring-cloud/spring-cloud-function/tree/main/spring-cloud-function-adapters/spring-cloud-function-adapter-azure[Azure].
@@ -21,13 +21,13 @@ It is primarily to accommodate _stateless serverless patterns_ where you simply
|===
| Method | Path | Request | Response | Status
| GET | /{supplier} | - | Items from the named supplier | 200 OK
| POST | /{consumer} | JSON object or text | Mirrors input and pushes request body into consumer | 202 Accepted
| PUT | /{consumer} | JSON object or text | Mirrors input and pushes request body into consumer | 202 Accepted
| DELETE | /{consumer} | JSON object or text | - | 204 NO CONTENT
| POST | /{function} | JSON object or text | The result of applying the named function | 200 OK
| PUT | /{function} | JSON object or text | The result of applying the named function | 200 OK
| GET | /{function}/{item} | - | Convert the item into an object and return the result of applying the function | 200 OK
| GET | /\{supplier} | - | Items from the named supplier | 200 OK
| POST | /\{consumer} | JSON object or text | Mirrors input and pushes request body into consumer | 202 Accepted
| PUT | /\{consumer} | JSON object or text | Mirrors input and pushes request body into consumer | 202 Accepted
| DELETE | /\{consumer} | JSON object or text | - | 204 NO CONTENT
| POST | /\{function} | JSON object or text | The result of applying the named function | 200 OK
| PUT | /\{function} | JSON object or text | The result of applying the named function | 200 OK
| GET | /\{function}/\{item} | - | Convert the item into an object and return the result of applying the function | 200 OK
|===
@@ -42,8 +42,8 @@ When POSTing text the response format might be different with Spring Boot 2.0 an
See <<Testing Functional Applications>> to see the details and example on how to test such application.
[[http-request-parameters]]
=== HTTP Request Parameters
As you have noticed from the previous table, you can pass an argument to a function as path variable (i.e., `/{function}/{item}`).
== HTTP Request Parameters
As you have noticed from the previous table, you can pass an argument to a function as path variable (i.e., `/\{function}/\{item}`).
For example, `http://localhost:8080/uppercase/foo` will result in calling `uppercase` function with its input parameter being `foo`.
While this is the recommended approach and the one that fits most use cases cases, there are times when you have to deal with HTTP request parameters (e.g., `http://localhost:8080/uppercase/foo?name=Bill`)
Reference in New Issue
Block a user
Blocking a user prevents them from interacting with repositories, such as opening or commenting on pull requests or issues. Learn more about blocking a user.
Oleg Zhurakousky