gradle-download-task
đź“Ą Adds a download task to Gradle that displays progress information
APACHE-2.0 License
This is a download task for Gradle. It displays progress information just like Gradle does when it retrieves an artifact from a repository. It is also able to download multiple files in parallel and supports concurrent execution with other tasks.
The plugin has been successfully tested with Gradle 5.0 up to 8.9. It should work with newer versions as well.
Who’s using gradle-download-task?
Usage
First, apply the plugin configuration:
plugins {
id "de.undercouch.download" version "5.6.0"
}
Then, use the Download task as follows:
task downloadFile(type: Download) {
src 'http://www.example.com/index.html'
dest layout.buildDirectory
}
By default, the plugin always performs a download even if the destination file
already exists. If you want to prevent files from being downloaded again, use
the overwrite flag (see description below).
task downloadFile(type: Download) {
src 'http://www.example.com/index.html'
dest layout.buildDirectory
overwrite false
}
As an alternative to the Download task, you may also use the download
extension to retrieve a file anywhere in your build script:
task myTask {
doLast {
// do something ...
// ... then download a file
download.run {
src 'http://www.example.com/index.html'
dest layout.buildDirectory
overwrite false
}
// ... do something else
}
}
Note that the download extension also has a runAsync method that downloads
a file asynchronously. It returns a CompletableFuture that either completes
successfully or exceptionally depending on whether the download has finished
successfully or if it has failed. Make sure to always wait for the result of
the CompletableFuture. Otherwise, errors might get lost.
Minimum requirements
The plugin requires:
- Gradle 5.x or higher
- Java 8 or higher
If you need to run the plugin with Gradle 2.x up to 4.x or Java 7, use gradle-download-task version 4.1.2.
Examples
Only download a file if it has been modified on the server
task downloadFile(type: Download) {
src 'http://www.example.com/index.html'
dest layout.buildDirectory
onlyIfModified true
}
Note that this example only works if the server supports the If-Modified-Since
request header and provides a Last-Modified timestamp in its response. If the
server supports entity tags (ETags) you may use onlyIfModified together with
useETag.
Concurrently download a list of files to a directory
task downloadMultipleFiles(type: Download) {
src([
'http://www.example.com/index.html',
'http://www.example.com/test.html'
])
dest layout.buildDirectory
}
Please note that you have to specify a directory as destination if you download multiple files. Otherwise, the plugin will fail.
Download files from a directory
If you want to download all files from a directory and the server provides a simple directory listing, you can use the following code:
task downloadDirectory {
doLast {
def dir = 'http://central.maven.org/maven2/de/undercouch/gradle-download-task/1.0/'
def urlLister = new org.apache.ivy.util.url.ApacheURLLister()
def files = urlLister.listFiles(new URL(dir))
download.run {
src files
dest layout.buildDirectory
}
}
}
Download and extract a ZIP file
To download and unpack a ZIP file, you can combine the download task plugin with Gradle's built-in support for ZIP files:
task downloadZipFile(type: Download) {
src 'https://github.com/michel-kraemer/gradle-download-task/archive/refs/tags/5.6.0.zip'
dest layout.buildDirectory.file('5.6.0.zip')
}
task downloadAndUnzipFile(dependsOn: downloadZipFile, type: Copy) {
from zipTree(downloadZipFile.dest)
into layout.buildDirectory
}
More examples
Please have a look at the examples directory for more code samples. You can
also read my blog post about
common recipes for gradle-download-task.
Download task
The download task and the extension support the following properties.
General
Tip! You may provide Groovy Closures or Kotlin Lambdas to the src
and dest properties to calculate their value at runtime.
Connection
Authentication
Advanced
Verify task
The plugin also provides a Verify task that can be used to check the integrity
of a downloaded file by calculating its checksum and comparing it to a
pre-defined value. The task succeeds if the file’s checksum equals the
given value and fails if it doesn’t.
Use the task as follows:
task verifyFile(type: Verify) {
src layout.buildDirectory.file('file.ext')
algorithm 'MD5'
checksum 'ce114e4501d2f4e2dcea3e17b546f339'
}
You can combine the download task and the verify task as follows:
task downloadFile(type: Download) {
src 'http://www.example.com/index.html'
dest layout.buildDirectory
}
task verifyFile(type: Verify, dependsOn: downloadFile) {
src layout.buildDirectory.file('index.html')
algorithm 'MD5'
checksum '09b9c392dc1f6e914cea287cb6be34b0'
}
The verify task supports the following properties:
DownloadDetails
If you specify an eachFile action, it will be called with an
instance of the DownloadDetails class, which provides details about a
download source and its target file. It can be used to change some aspects of
the target file (e.g. its name or relative path).
DownloadDetails provides the following properties:
Example
eachFile { f ->
f.name = f.name.toLowerCase()
if (f.sourceURL.path.toLowerCase().endsWith(".jpg")) {
f.path = "images/" + f.path
}
}
Proxy configuration
You can configure a proxy server by setting standard JVM system properties. The plugin uses the same system properties as Gradle. You can set them in the build script directly. For example, the proxy host can be set as follows:
System.setProperty("http.proxyHost", "www.somehost.org");
Alternatively, you can set the properties in a gradle.properties file like
this:
systemProp.http.proxyHost=www.somehost.org
systemProp.http.proxyPort=8080
systemProp.http.proxyUser=userid
systemProp.http.proxyPassword=password
systemProp.http.nonProxyHosts=*.nonproxyrepos.com|localhost
Put this file in your project’s root directory or in your Gradle home directory.
HTTPS is also supported:
systemProp.https.proxyHost=www.somehost.org
systemProp.https.proxyPort=8080
systemProp.https.proxyUser=userid
systemProp.https.proxyPassword=password
systemProp.https.nonProxyHosts=*.nonproxyrepos.com|localhost
Migrating from version 4.x to 5.x
gradle-download-task 5.0.0 introduces the following breaking changes:
- The
authSchemeproperty has been removed. The plugin now automatically
detects the correct scheme to use based on the server response. - The
downloadextension was incompatible with Gradle 8. Also, using it
from Kotlin build scripts was rather inconvenient. It is therefore now
necessary to call the extension through itsrunmethod. Replace
download { ... }withdownload.run { ... }. The same applies to the
verifyextension.
Migrating from version 3.x to 4.x
In gradle-download-task 4.x, we made the following breaking changes to the API:
- The plugin now requires Gradle 2.x (or higher) and Java 7 (or higher)
- We removed the
timeoutproperty and introducedconnectTimeoutand
readTimeoutinstead. This allows you to control the individual timeouts
better. Also, it improves compatibility with Gradle 5.x, where all tasks have
atimeoutproperty by default. - The
credentialsproperty has been removed. The same applies to the
possibility to pass instances of Apache HttpClient’sAuthSchemeto the
authSchemeproperty. The stringsBasicandDigestare now the only
accepted values. There is no replacement. If you need this functionality,
please file an issue. - The properties
requestInterceptorandresponseInterceptorhave been
removed. There is no replacement. Again, if you need this functionality,
please file an issue.
License
The plugin is licensed under the Apache License, Version 2.0.
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
