pcdm-manifests

Implementation of the IIIF Presentation API that generates IIIF Manifests from PCDM objects in a Fedora repository.

Quick Start

Requires Ruby v3.0.6

git clone [email protected]:umd-lib/pcdm-manifests.git
cd pcdm-manifests

gem install bundler
bundle install
rails server

JSON manifests of an issue can be obtained by making an HTTP GET request in the following format.

curl http://localhost:3000/manifests/IIIF_ID/manifest

The general structure of the IIIF_ID is prefix:id. The exact format of the id varies by handler.

Handlers

fcrepo

• Prefix: fcrepo
• ID: The URL_encoded repository path to the resource (part of the PCDM resource URI after the Fedora base URI). There is also a shorthand that uses :: to indicate the presence of a 4-element pairtree before a UUID.

Example

	Value
Fedora URI	https://fcrepolocal/fcrepo/rest/pcdm/ab/b4/b3/04/abb4b304-5e96-478f-8abb-8c5aafd42223
Fedora Base URI	https://fcrepolocal/fcrepo/rest/
IIIF ID	fcrepo:pcdm%2Fab%2Fb4%2Fb3%2F04%2Fabb4b304-5e96-478f-8abb-8c5aafd42223 OR fcrepo:pcdm::abb4b304-5e96-478f-8abb-8c5aafd42223
Manifest URI	http://localhost:3000/manifests/fcrepo:ab%2Fb4%2Fb3%2F04%2Fabb4b304-5e96-478f-8abb-8c5aafd42223/manifest OR http://localhost:3000/manifests/fcrepo:pcdm::abb4b304-5e96-478f-8abb-8c5aafd42223/manifest

fedora2

• Prefix: fedora2
• ID: The umd: PID of the resource.

Configuration

The following environment variables are used to configure the services used by PCDM Manifests in production:

Variable	Purpose
SOLR_URL	URL of the Solr core to query; this core must have a pcdm request handler
FCREPO_URL	Base URL of the Fedora repository
FEDORA2_URL	Base URL of the Fedora 2 repository
FEDORA2_SOLR_URL	URL of the Solr core to query for the Fedora 2 metadata
FCREPO_SOLR_URL	Should be set to the same as SOLR_URL
IIIF_IMAGE_URL	Base URL for the IIIF Image API service
IIIF_MANIFEST_URL	Base URL for this service

See config/iiif.yml for examples.

Docker

This repository contains a Dockerfile for building a deployable image of this application:

# build an image tagged with the current application version
VERSION="$(rails app:version)" .
docker build -t "pcdm-manifests:$VERSION" .

# build an image tagged with the current application version, plus the current
# git commit hash (useful for development builds)
VERSION="$(rails app:version)-$(git rev-parse --short=8 HEAD)" .
docker build -t "pcdm-manifests:$VERSION" .

To run the image, bind port 3000 to 3000 on localhost:

docker run -it --rm -p 3000:3000 -e RAILS_ENV='development' "pcdm-manifests:$VERSION"

There should be a simple splash page at http://localhost:3000/

Building the Docker Image for K8s Deployment

The following procedure uses the Docker "buildx" functionality and the Kubernetes "build" namespace to build the Docker image. This procedure should work on both "arm64" and "amd64" MacBooks.

The image will be automatically pushed to the Nexus.

Local Machine Setup

See https://github.com/umd-lib/k8s/blob/main/docs/DockerBuilds.md in GitHub for information about setting up a MacBook to use the Kubernetes "build" namespace.

Creating the Docker image

1. In an empty directory, checkout the Git repository and switch into the directory:

   $ git clone [email protected]:umd-lib/pcdm-manifests.git
   $ cd pcdm-manifests

2. Checkout the appropriate Git tag, branch, or commit for the Docker image.

3. Set up an "APP_TAG" environment variable:

   $ export APP_TAG=<DOCKER_IMAGE_TAG>

   where <DOCKER_IMAGE_TAG> is the Docker image tag to associate with the Docker image. This will typically be the Git tag for the application version, or some other identifier, such as a Git commit hash. For example, using the Git tag of "1.2.0":

   $ export APP_TAG=1.2.0

   Alternatively, to use the Git branch and commit:

   $ export GIT_BRANCH=`git rev-parse --abbrev-ref HEAD`
   $ export GIT_COMMIT_HASH=`git rev-parse HEAD`
   $ export APP_TAG=${GIT_BRANCH}-${GIT_COMMIT_HASH}

4. Switch to the Kubernetes "build" namespace:

   $ kubectl config use-context build

5. Create the "docker.lib.umd.edu/pcdm-manifests" Docker image:

   $ docker buildx build --no-cache --platform linux/amd64 --push --no-cache \
       --builder=kube  -f Dockerfile -t docker.lib.umd.edu/pcdm-manifests:$APP_TAG .

   The Docker image will be automatically pushed to the Nexus.

License

See the LICENSE file for license rights and limitations (Apache 2.0).