Update Report 

update and related tasks produce a value of type sbt.UpdateReport This data structure provides information about the resolved configurations, modules, and artifacts. At the top level, UpdateReport provides reports of type ConfigurationReport for each resolved configuration. A ConfigurationReport supplies reports (of type ModuleReport) for each module resolved for a given configuration. Finally, a ModuleReport lists each successfully retrieved Artifact and the File it was retrieved to as well as the Artifacts that couldn’t be downloaded. This missing Artifact list is always empty for update, which will fail if it is non-empty. However, it may be non-empty for updateClassifiers and updateSbtClassifers.

Filtering a Report and Getting Artifacts 

A typical use of UpdateReport is to retrieve a list of files matching a filter. A conversion of type UpdateReport => RichUpdateReport implicitly provides these methods for UpdateReport. The filters are defined by the DependencyFilter, ConfigurationFilter, ModuleFilter, and ArtifactFilter types. Using these filter types, you can filter by the configuration name, the module organization, name, or revision, and the artifact name, type, extension, or classifier.

The relevant methods (implicitly on UpdateReport) are:

def matching(f: DependencyFilter): Seq[File]

def select(configuration: ConfigurationFilter = ...,
  module: ModuleFilter = ...,
  artifact: ArtifactFilter = ...): Seq[File]

Any argument to select may be omitted, in which case all values are allowed for the corresponding component. For example, if the ConfigurationFilter is not specified, all configurations are accepted. The individual filter types are discussed below.

Filter Basics 

Configuration, module, and artifact filters are typically built by applying a NameFilter to each component of a Configuration, ModuleID, or Artifact. A basic NameFilter is implicitly constructed from a String, with * interpreted as a wildcard.

import sbt._
// each argument is of type NameFilter
val mf: ModuleFilter = moduleFilter(organization = "*sbt*",
  name = "main" | "actions", revision = "1.*" - "1.0")

// unspecified arguments match everything by default
val mf: ModuleFilter = moduleFilter(organization = "net.databinder")

// specifying "*" is the same as omitting the argument
val af: ArtifactFilter = artifactFilter(name = "*", `type` = "source",
  extension = "jar", classifier = "sources")

val cf: ConfigurationFilter = configurationFilter(name = "compile" | "test")

Alternatively, these filters, including a NameFilter, may be directly defined by an appropriate predicate (a single-argument function returning a Boolean).

import sbt._

// here the function value of type String => Boolean is implicitly converted to a NameFilter
val nf: NameFilter = (s: String) => s.startsWith("dispatch-")

// a Set[String] is a function String => Boolean
val acceptConfigs: Set[String] = Set("compile", "test")
// implicitly converted to a ConfigurationFilter
val cf: ConfigurationFilter = acceptConfigs

val mf: ModuleFilter = (m: ModuleID) => m.organization contains "sbt"

val af: ArtifactFilter = (a: Artifact) => a.classifier.isEmpty

ConfigurationFilter 

A configuration filter essentially wraps a NameFilter and is explicitly constructed by the configurationFilter method:

def configurationFilter(name: NameFilter = ...): ConfigurationFilter

If the argument is omitted, the filter matches all configurations. Functions of type String => Boolean are implicitly convertible to a ConfigurationFilter. As with ModuleFilter, ArtifactFilter, and NameFilter, the &, |, and - methods may be used to combine ConfigurationFilters.

import sbt._
val a: ConfigurationFilter = Set("compile", "test")
val b: ConfigurationFilter = (c: String) => c.startsWith("r")
val c: ConfigurationFilter = a | b

(The explicit types are optional here.)

ModuleFilter 

A module filter is defined by three NameFilters: one for the organization, one for the module name, and one for the revision. Each component filter must match for the whole module filter to match. A module filter is explicitly constructed by the moduleFilter method:

def moduleFilter(organization: NameFilter = ..., name: NameFilter = ..., revision: NameFilter = ...): ModuleFilter

An omitted argument does not contribute to the match. If all arguments are omitted, the filter matches all ModuleIDs. Functions of type ModuleID => Boolean are implicitly convertible to a ModuleFilter. As with ConfigurationFilter, ArtifactFilter, and NameFilter, the &, |, and - methods may be used to combine ModuleFilters:

import sbt._
val a: ModuleFilter = moduleFilter(name = "dispatch-twitter", revision = "0.7.8")
val b: ModuleFilter = moduleFilter(name = "dispatch-*")
val c: ModuleFilter = b - a

(The explicit types are optional here.)

ArtifactFilter 

An artifact filter is defined by four NameFilters: one for the name, one for the type, one for the extension, and one for the classifier. Each component filter must match for the whole artifact filter to match. An artifact filter is explicitly constructed by the artifactFilter method:

def artifactFilter(name: NameFilter = ..., `type`: NameFilter = ...,
  extension: NameFilter = ..., classifier: NameFilter = ...): ArtifactFilter

Functions of type Artifact => Boolean are implicitly convertible to an ArtifactFilter. As with ConfigurationFilter, ModuleFilter, and NameFilter, the &, |, and - methods may be used to combine ArtifactFilters:

import sbt._
val a: ArtifactFilter = artifactFilter(classifier = "javadoc")
val b: ArtifactFilter = artifactFilter(`type` = "jar")
val c: ArtifactFilter = b - a

(The explicit types are optional here.)

DependencyFilter 

A DependencyFilter is typically constructed by combining other DependencyFilters together using &&, ||, and --. Configuration, module, and artifact filters are DependencyFilters themselves and can be used directly as a DependencyFilter or they can build up a DependencyFilter. Note that the symbols for the DependencyFilter combining methods are doubled up to distinguish them from the combinators of the more specific filters for configurations, modules, and artifacts. These double-character methods will always return a DependencyFilter, whereas the single character methods preserve the more specific filter type. For example:

import sbt._

val df: DependencyFilter =
  configurationFilter(name = "compile" | "test") &&
  artifactFilter(`type` = "jar") ||
  moduleFilter(name = "dispatch-*")

Here, we used && and || to combine individual component filters into a dependency filter, which can then be provided to the UpdateReport.matches method. Alternatively, the UpdateReport.select method may be used, which is equivalent to calling matches with its arguments combined with &&.