Allow to specify target migrate version to match the default behavior

[voronaam]

I would like to allow a special value of the -target parameter for the migrate operation to specify exactly the same behaviour as when -target parameter is omitted.

Using command-line interface as an example:

flyway -target=${parameters.version} migrate

We would want parameters.version to come as a configurable parameter from an upstream pipeline. However, there is no value for this parameter to match the default behaviour "migrate to the latest".

The -target already has one special value ("current"). I propose another special value. It could be either of "null", "empty", "latest". When specified, FlywayDB migrate behaviour exactly matches one when the -target parameter is omitted.

I will create a PR for this proposal. This can be as simple as:

diff --git a/flyway-core/src/main/java/org/flywaydb/core/api/configuration/ClassicConfiguration.java b/flyway-core/src/main/java/org/flywaydb/core/api/configuration/ClassicConfiguration.java
index 8039bb1d1..d6472810b 100644
--- a/flyway-core/src/main/java/org/flywaydb/core/api/configuration/ClassicConfiguration.java
+++ b/flyway-core/src/main/java/org/flywaydb/core/api/configuration/ClassicConfiguration.java
@@ -1577,7 +1577,7 @@ public class ClassicConfiguration implements Configuration {
             setIgnoreFutureMigrations(ignoreFutureMigrationsProp);
         }
         String targetProp = props.remove(ConfigUtils.TARGET);
-        if (targetProp != null) {
+        if (targetProp != null && !"null".equalsIgnoreCase(targetProp)) {
             setTarget(MigrationVersion.fromVersion(targetProp));
         }
         Boolean outOfOrderProp = getBooleanProp(props, ConfigUtils.OUT_OF_ORDER);

[axelfontaine]

We will use the special value latest for this. We'll implement this as part of 6.0.

[voronaam]

Thank you.

The naming is the hardest part for me. I am not in any way attached to the null value I used in the PR :)

Updated the PR to match the selected value.

[voronaam]

I closed the Pull Request - looks like you are going to address the change inside your own team.

[MikielAgutu]

Thanks for the feature request. From V6, this will be possible via a new special value latest for the 'target' configuration option. So you could do something like:

flyway -target=latest migrate

The option will also register for other commands (undo, info, etc) also.