private static async Task RunDockerBuild(
string imageName, DockerBuildUnwrap build, string[]?cacheFrom, Resource logResource, string?target = null)
{
// Prepare the build arguments.
var buildArgs = new List <string>(new[] { "build" });
if (!string.IsNullOrEmpty(build.Dockerfile))
{
buildArgs.AddRange(new[] { "-f", build.Dockerfile }); // add a custom Dockerfile location.
}
if (build.Args != null)
{
foreach (var arg in build.Args.Keys)
{
buildArgs.AddRange(new[] { "--build-arg", $"{arg}={build.Args[arg]}" });
}
}
if (build.Target != null)
{
buildArgs.AddRange(new[] { "--target", build.Target });
}
if (build.CacheFrom != null)
{
var cacheFromImages = cacheFrom;
if (cacheFromImages != null && cacheFromImages.Length > 0)
{
buildArgs.AddRange(new[] { "--cache-from", string.Join("", cacheFromImages) });
}
}
if (build.ExtraOptions != null)
{
buildArgs.AddRange(build.ExtraOptions);
}
buildArgs.Add(build.Context !); // push the docker build context onto the path.
buildArgs.AddRange(new[] { "-t", imageName }); // tag the image with the chosen name.
if (target != null)
{
buildArgs.AddRange(new[] { "--target", target });
}
await RunCommandThatMustSucceed("docker", buildArgs.ToArray(), logResource,
reportFullCommandLine : true, stdin : null, build.Env).ConfigureAwait(false);
}
private static async Task <(string imageId, string[] stages)> BuildImageAsync(
string imageName, Union <string, DockerBuildUnwrap> pathOrBuild, Resource logResource, string[]?cacheFrom)
{
DockerBuildUnwrap build = pathOrBuild.IsT0 ? new DockerBuildUnwrap {
Context = pathOrBuild.AsT0
} : pathOrBuild.AsT1;
// If the build context is missing, default it to the working directory.
if (build.Context == null)
{
build.Context = ".";
}
Log.Info(
$"Building container image '{imageName}': context={build.Context}" +
(build.Dockerfile != null ? $", dockerfile={build.Dockerfile}" : "") +
(build.Args != null ? $", args={JsonSerializer.Serialize(build.Args)}" : "") +
(build.Target != null ? $", target={build.Target}" : ""),
logResource, ephemeral: true);
// If the container build specified build stages to cache, build each in turn.
var stages = new List <string>();
if (build.CacheFrom?.Stages != null)
{
foreach (var stage in build.CacheFrom.Stages)
{
await RunDockerBuild(LocalStageImageName(imageName, stage),
build, cacheFrom, logResource, stage).ConfigureAwait(false);
stages.Add(stage);
}
}
//// Invoke Docker CLI commands to build.
await RunDockerBuild(imageName, build, cacheFrom, logResource).ConfigureAwait(false);
// Finally, inspect the image so we can return the SHA digest. Do not forward the output of this
// command this to the CLI to show the user.
var inspectResult = await RunCommandThatMustSucceed(
"docker", new[] { "image", "inspect", "-f", "{{.Id}}", imageName }, logResource).ConfigureAwait(false);
if (string.IsNullOrEmpty(inspectResult))
{
throw new ResourceException($"No digest available for image {imageName}", logResource);
}
// From https://docs.docker.com/registry/spec/api/#content-digests
//
// the image id will be a "algorithm:hex" pair. We don't care about the algorithm part. All we
// want is the unique portion we can use elsewhere. Since we are also going to place this in an
// image tag, we also don't want the colon, as that's not legal there. So simply grab the hex
// portion after the colon and return that.
var imageId = inspectResult.Trim();
var colonIndex = imageId.LastIndexOf(":");
imageId = colonIndex < 0 ? imageId : imageId.Substring(colonIndex + 1);
return(imageId, stages.ToArray());
}
