The command ng update @my/lib@version downloads the specified version of the library and launches all schematics listed in its migrations.json that have an appropriate property of "version" within the semver range from >installedVersion to <=targetVersion.
Example
For instance, consider the following conditions:
- The locally installed version of
@my/libin my project is1.1.0. - The latest published npm version of
@my/libis4.8.9. - Now, when we run
ng update @my/lib(or...@my/lib@4or...@my/lib@4.8or...@my/lib@4.8.9, it doesn't matter), - and the file
migration.jsonof@my/libcontains migrations for the"version"2.0.0and4.5.0:
{
"schematics": {
"migration-v2": {
"version": "2.0.0",
"factory": "./migration-v2#migrate",
"description": "Migration for v2.0.0"
},
"migration-v4.5": {
"version": "4.5.0",
"factory": "./migration-v4_5#migrate",
"description": "Migration for v4.5.0"
},
}
}
...then the following migrations will be executed, in ascending order of version:
- Migration for v2.0.0
- Migration for v4.5.0
This is because they fall between the currently installed version (>1.1.0) and the target version (<=4.8.9).
Note: If we were to run ng update @my/lib@ with the target version lower than 4.5.0, for example, ng update @my/lib@3, only the following migration would be executed:
- Migration for v2.0.0
However, the Migration for v4.5.0 would not run.
Angular CLI source code analysis
Here's a proof in the source code of the Angular CLI:
If the "version" field from
migrations.jsonbelongs to the appropriate semver range, then this migration is launched (see source).The appropriate semver range means something between
>fromVersionand<=toVersion(see sources: executeMigration() and invocation of executeMigration()).The
fromVersionandtoVersionrespectively mean:installed.versionandtarget.version(see source).
Therefore, all migrations between >installed.version and <=target.version are launched.
If you really feel like buying me a coffee
... then feel free to do it. Many thanks! 🙌
Top comments (5)
Hi there doesn't seem to be a lot of documentation around for custom ng-update implementation, and those I have found, I have managed to cobble together, however.
1) I have got the ng-add to work fine
2) I have got the ng update @myscope/mylib to work, i.e. just updates the package only
but .. I can only get migrations to work if I do this ..
ng update @myscope/mylib --migrate-only --from x.xx (and also adding --to x.xx)
so the above picks the correct schematics based on version in my migrations.json and runs them fine, so the setup must be ok
I thought by running
ng update @myscope/mylib@x.xx
would both update package and then run migrations automatically after, is this stil the case or has something changed ? Am i missing something ?
thanks for any insight you may have
That's exactly what I'd expect too! 🤔
Strange eh? must be missing something ? .. but update package works fine, and using --migrate-only runs the correct versioned migration schematics .. just not one after the other in one-liner ... not sure where to look, as doing the --migrate-only was part of my "debugging" ... I am using v18 angular, I know there been a few changes, but cant see trawling through their code
For debugging Angular CLI internal code, try runninng your
ng update...inside VSCode Javascript Debugging Terminal. But before doing it, add breakpoints in your VSCode (add red dots at a margin near line numbers, by clicking) in JS files inside the foleder/node_modules/@angular/cli/src/commands/update/..., e.g. in its files.../cli.jsand.../schematic/index.js.Please mind hovering variables with mouse, to inspect their values, when runtime stops on your breakpoint. I hope this way you'll be able to find out the root cause of the problem.
I'd put breakpoints the following places and go line-by-line, when debugger stops on those breakpoints after running your
ng update...inside the VSCode Javascript Debugging Terminal:Note: After running your
ng update...inside the VSCode Javascript Debugging Terminal, you should see the Debugger panel (shown in the picture below) in VSCode, which will allow you to debug similarly like in Chrome Dev Tools, e.g. step over a line, step into the current fucntion, step outside the current function:Will have a go at this in a bit, thanks