Generating AssemblyInfo files with Gulp

When changing a project’s build script over to Gulpjs, I ran into a problem with one step - creating an AssemblyInfo.cs file.

My projects have their version number in the package.json file, and I read that at compile time, pull in some information from the build server, and write that to an AssemblyVersion.cs file. This file is not tracked by git, and I don’t want it showing up as a modification if you run the build script locally.

The problem is that the gulp-dotnet-assembly-info package doesn’t support generation of files, only updating. To get around this I used the gulp-rename package to read a template file, and generate the non-tracked AssemblyVersion.cs file.

Steps

First, create an AssemblyVersion.base file, and save it somewhere in your repository. I usually put it next to the gulpfile, or in the projects Properties directory, depending on if the project has multiple assemblies or not. This file can be added and tracked by git - it won’t get changed.

using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

[assembly: AssemblyVersion("0.0.0")]
[assembly: AssemblyFileVersion("0.0.0")]
[assembly: AssemblyDescription("Build: 0, Commit Sha: 0")]

Next install the two gulp modules, and import into your gulpfile:

npm install gulp-rename --save
npm install gulp-dotnet-assembly-info --save

var rename = require('gulp-rename');
var assemblyInfo = require('gulp-dotnet-assembly-info');

In the gulp file, read the package.json file and the environment variables. I do this once at the begining of my gulpfile and use the config all over the place.

var project = JSON.parse(fs.readFileSync("./package.json"));

var config = {
  name: project.name,
  version: project.version,
  commit: process.env.APPVEYOR_REPO_COMMIT || "0",
  buildNumber: process.env.APPVEYOR_BUILD_VERSION || "0",
}

Then add a task to create a new AssemblyVersion.cs file. Change the src parameter to match where you saved the AssemblyVersion.base file.

gulp.task('version', function() {
  return gulp
    .src(config.name + '/Properties/AssemblyVersion.base')
    .pipe(rename("AssemblyVersion.cs"))
    .pipe(assemblyInfo({
      version: config.version,
      fileVersion: config.version,
      description: "Build: " +  config.buildNumber + ", Sha: " + config.commit
    }))
    .pipe(gulp.dest('./' + config.name + '/Properties'));
});

Don’t forget to reference the AssemblyVersion.cs file in your csproj!

You can see a full gulpfile with this in here: Magistrate gulpfile.

Steps#

Steps