SciCatLive ¶
Get set up with an instance of SciCat to explore the metadata catalog. SciCatlive provides a flexible and easy way to learn about SciCat and its features for people who are looking to integrate SciCat into their environment. For a user guide please see original documentation .
This project requires docker and docker compose. The docker version must be later than 2.29.0 to support this project.
First stable version ¶
Release
v3.0
is the first stable and reviewed version of SciCatLive.
Steps ¶
Windows specific instructions (click to expand)
Running this project on Windows is not officialy supported, you should use Windows Subsystem for Linux (WSL).
However, if you want to run it on Windows you have to be careful about:
- This project makes use of symbolic links, Windows and git for Windows have to be
configured to handle them
.
- End of lines, specifically in shell scripts. If you have the git config parameter
auto.crlf
set to
true
, git will replace LF by CRLF causing shell scripts and maybe other things to fail.
- This project uses the variable
${PWD}
to ease path resolution in bind mounts. In PowerShell/Command Prompt, the
PWD
environment variable doesn't exist so you would need to set in manually before running any
docker compose
command.
-
Clone the repository
git clone https://github.com/SciCatProject/scicatlive.git
-
Run with the following command inside the directory
docker compose up -d
Default setup ¶
By running
docker compose up -d
these steps take place:
- a mongodb container is created with some initial data.
- the SciCat backend v4 container is created and connected to (1).
- the SciCat frontend container is created and connected to (2).
-
a reverse
proxy
container is created and routes traffic to (2) and (3) through localhost subdomains, in the form:
http://${service}.localhost
. The frontend is available at simplyhttp://localhost
. -
Some services have additional endpoints that can be explored in SciCatLive which would follow
http://${service}.localhost/${prefix}
. For example, the backend API can be explored through a Swagger UI athttp://backend.localhost/explorer
. For more information on the paths used by these routes see the original documentation for these services.
Extra services and features ¶
SciCat has extra features as part of its core as well as integrating with external services.
SciCat features that extend the backend are:
- Jobs - this mechanism posts to a message broker , which can then trigger down stream processes . To use this a RabbitMQ server is enabled.
- Elasticsearch - creates an elasticsearch service to provide full text search in the backend.
Services that can be integrated with SciCat are:
- LDAP - authentication and authorization from an LDAP server
- OIDC - authentication and authorization using an OIDC provider
- SearchAPI - for better free text search in the metadata based on the PANOSC search-api
- LandingPage - a public interface for published datasets landingpage
- JupyterHub - Adds an instance of JupyterHub which demonstrates ingestion and extraction of metadata using pyscicat .
To simply enable one or more of these extra services configure them by setting the proper environment variable(s) and/or compose profile(s) from this table .
For a complete guide on how to customise or configure any service, including the default ones, please refer to these sections:
- manually select the services
- use docker compose env variables to enable features (supported values from this table )
- use docker compose profiles to enable extra services (supported values from this table )
- modify the service-specific config to customise specific services
- add entrypoints to control startup logic
For a guide on how to add a new service, please refer to this section .
Dependencies ¶
Here below we show the dependencies, including the ones of the
extra services
(if
B
depends on
A
, then we visualize it as
A --> B
):
graph TD
subgraph services
subgraph backend
backends[v3*/v4*]
end
mongodb --> backend
backend --> frontend
backend --> searchapi
backend --> landingpage
backend --> jupyter
end
proxy -.- services
%% CSS Styling
linkStyle 5 marker-end:none
We flag with
*
the services which have extra internal dependencies, which are not shared.
Select the services ¶
The user can selectively decide the containers to spin up and the dependencies will be resolved accordingly. The available services are in the services folder and are called consistently.
For example, one could decide to only run the
backend
by running (be aware that this will not run the
proxy
, so the service will not be available at
backend.localhost
):
docker compose up -d backend
(or a list of services, for example, with the proxy
docker compose up -d backend proxy
)
This will run, from the previous section , (1) and (2) but skip the rest.
Accordingly (click to expand)...
docker compose up -d frontend
Will run, from the previous section , (1), (2) and (4) but skip (5).
And
docker compose --profile search up -d searchapi
Will run, from the
previous section
, (1) and (2), skip (3) and (4), and add the
searchapi
service.
Make sure to check the
backend compatibility
when choosing services and setting
docker compose env vars and profiles
.
Docker compose env variables ¶
They are used to modify existing services where whenever enabling the feature requires changes in multiple services. They also have the advantage, compared to docker profiles, of not needing to define a new profile when a new combination of features becomes available. To set an env variable for docker compose, either assign it in the shell or change the .env file. To later unset it, either unset it from the shell or assign it an empty value, either in the shell or in the .env file.
For example, to use the Jobs functionality of SciCat change
JOBS_ENABLED
to true before running your
docker compose
command or simply export it in the shell. For all env configuration options see
here
.
Docker compose profiles ¶
They are used when adding new services or grouping services together (and do not require changes in multiple services). To enable any, run
docker compose --profile <PROFILE> up -d
, or export the
COMPOSE_PROFILES
env variable as described
here
. If needed, the user can specify more than one profile in the CLI by using the flag as
--profile <PROFILE1> --profile <PROFILE2>
.
For example
docker compose --profile analysis
sets up a jupyter hub with some notebooks for ingesting data into SciCat, as well as the related services (backend, mongodb, proxy). For more information on profiles available in SciCat live see the following
table
.
Docker compose profiles and env variables configuration options ¶
Type | Env key | Value: Service/Feature | Default | Backend Compatibility | Description | Other impacted services |
---|---|---|---|---|---|---|
profile |
COMPOSE_PROFILES
|
analysis
: jupyter
search
: searchapi,landingpage
'*'
: jupyter,searchapi,landingpage
|
''
|
* |
|
|
env |
BE_VERSION
|
v3
: backend/v3
v4
: backend/v4
|
v4
|
as set | Sets the BE version to use in (2) of default setup to v3 | mongodb,frontend |
env |
JOBS_ENABLED
|
true
: rabbitmq,archivemock,jobs feature
|
''
|
v3 | Creates a RabbitMQ message broker which the BE posts to and the archivemock listens to. It emulates the data long-term archive/retrieve workflow | |
env |
ELASTIC_ENABLED
|
true
: elastic,elastic feature
|
''
|
v4 | Creates an elastic search service and sets the BE to use it for full-text searches | |
env |
LDAP_ENABLED
|
true
: ldap auth
|
''
|
* | Creates an LDAP service and sets the BE to use it as authentication backend | |
env |
OIDC_ENABLED
|
true
: oidc auth
|
''
|
* | Creates an OIDC identity provider and sets the BE to use it as authentication backend | |
env |
DEV
|
true
: backend,frontend,searchapi,archivemock in DEV mode
|
''
|
* | The SciCat services' environment is prepared to ease the development in a standardized environment | |
env |
<SERVICE>_HTTPS_URL
|
<URL>
: HTTPS termination
|
''
|
* | Requests the TLS certificate for the URL to LetsEncrypt through the proxy |
After optionally setting any configuration option, one can still select the services to run as described here .
DEV configuration ¶
(click to expand)
To provide a consistent environment where developers can work, the
DEV=true
option creates the SciCat services (see DEV from
here
for the list), but instead of running them, it just creates the base environment that each service requires. For example, for the
backend
, instead of running the web server, it creates a NODE environment with
git
where one can develop and run the unit tests. This is useful as often differences in environments create collaboration problems. It should also provide an example of the configuration for running tests. Please refer to the services' README for additional information, or to the Dockerfile
CMD
of the components' GitHub repo if not specified otherwise. The
DEV=true
affects the SciCat services only.
Please be patient when using DEV as each container sets the env for dev, including the requirements for testing, which might take a little to finish. To see if any special precaution is required to run the tests, refer to the
compose.dev.test.yaml
file where tests files are referenced and refer to their content.
When DEV=true
, if you want to run tests when the containers start, you can do so by including the
compose.dev.test.yaml
compose file.
docker compose -f compose.yaml -f .github/compose.dev.test.yaml ...
It is very convenient if using VSCode , as, after the docker services are running, one can attach to it and start developing using all VSCode features, including version control and debugging.
To ease writing DEV configuration, a dev template is provided
here
and each component inhearits from it, as you can see
here
setting the componenent specific variables from the relative
.env file
.
Docker compose applies a
precedence mechanism
whenever the same variable is defined in
.env
files in nested folders, with precedence to the folder where the default
COMPOSE_FILE
lives. This means that the current template cannot be used in case of nested components, at least for the parts where local variables are used. There is no conflict with variables defined multiple times in
.env
files at the same level.
To prevent git unpushed changes from being lost when a container is restarted, the work folder of each service, when in DEV mode, is mounted to a docker volume, with naming convention
${COMPOSE_PROJECT_NAME}_<service>_dev
. Make sure, to commit and push frequently, especially before removing docker volumes to push the relevant changes.
As the DEV containers pull from upstream/latest, there is no guarantee of their functioning outside of releases. If they fail to start, try, as a first option, to build the image from a tag (e.g.
build context
) using the
TAG
and then git checkout to that tag (e.g. set
GITHUB_REPO
including the branch using the same syntax and value as the build context). You can achieve this, by setting the
GITHUB_REPO
env variable in the component
.env
file (e.g. the
frontend env file
) as follows:
- GITHUB_REPO=https://github.com/SciCatProject/frontend.git
+ GITHUB_REPO=https://github.com/SciCatProject/frontend.git#v4.4.1
The repo is checkout at that particular commit only if the docker volume does not yet exist.
TLS configuration ¶
You can enable TLS termination of desired services by setting the
<SERVICE>_HTTPS_URL
, by setting the full URL, including
https://
. The specified HTTPS URL will get a
letsencrypt
generated certificate through the proxy setting. For more details see the
proxy instructions
. After setting some URLs, the required changes in dependent services are automatically resolved, as explained for example
here
. Whenever possible, we use either the docker internal network or the localhost subdomains.
Please make sure to set all required
<SERVICE>_HTTPS_URL
whenever enabling one, as mixing public URLs and
localhost
ones might be tricky. See, for example, what is described in the
frontend documentation
and the
backend documentation
.
Service-specific config ¶
It can be changed whenever needing to configure a service independently from the others.
Every service folder (inside the services parent directory) contains its configuration and some instructions, at least for the non-third-party containers.
For example, to configure the frontend , the user can change any file in the frontend config folder, for which instructions are available in the README file.
After any configuration change,
docker compose up -d
must be rerun, to allow loading the changes.
Entrypoints ¶
Sometimes, it is useful to run init scripts (entrypoints) before the service starts. For example, for the
frontend
composability, it is useful to specify its configuration through multiple JSON files, with different scopes, which are then merged by a
init script
. For this reason, one can define
common entrypoints
and service-specific ones (e.g.
backend v4 ones
) which can be run inside the container, before the service starts (i.e. before the docker compose
command
is executed). Whenever these entrypoints are shared between services, it is recommended to place them in an
entrypoints
folder below the outermost service (e.g.
this one
).
To ease the iterative execution of multiple init scripts, one can leverage the
loop_entrypoints
utility, which loops alphabetically over
/docker-entrypoinst/*.sh
and executes each. This is in use in some services (e.g. in the
frontend
), so one can add additional init steps by mounting them, one by one, as volumes inside the container in the
/docker-entrypoints
folder and naming them depending on the desired order (eventually rename the existing ones as well).
If the service does not support entrypoints yet, one needs to: ¶
(click to expand):
- mount the loop_entrypoint.sh as a volume inside the container
-
mount any service-specific init script as a volume in the container in the folder
/docker-entrypoints/*.sh
, naming them sequentially, depending on the desired execution order -
override the
entrypoint
field in the service -
specify the service
command
See for example here .
Add a new service ¶
Please note that services should, in general, be defined by their responsibility, rather than by their underlying technology, and should be named so.
Basic ¶
To add a new service (see the jupyter service for a minimal example):
- create a dedicated folder in the services one *
- name it as the service
-
create the
compose.yaml
file -
eventually, add a
README.md
file in the service - eventually, add the platform field, as described here
- include the reference to (3) to the global compose include list *
- eventually, update the main README.md
* if the service to add is not shared globally, but specific to one particular service or another implementation of the same component, add it to the
services
folder relative to the affected service, and in (6) add it to its inclusion list. See an example of a service relative
services folder here
and a
relative inclusion list here
.
Supported OS architectures ¶
Since some images are not built with multi-arch, in particular the SciCat ones, make sure to specify the platform of the service in the compose, when needed, to avoid possible issues when running
docker compose up
on different platforms, for example on MAC with arm64 architecture. See for example the
searchapi compose
.
Advanced ¶
(click to expand)
To add a new service, with advanced configuration (see the backend for an extensive example, or/and this PR which added the landingpage ):
- follow the steps from the basic section
- eventually, include any service, in the service-specific folder which is specific to the service and not shared by other, more general services, e.g. here . This folder should also include different versions of the same service, e.g. v3 and v4 here
-
eventually, if the service supports ENVs , leverage the include override feature from docker compose. For this:
-
create a
compose.base.yaml
file, e.g. here , which should contain thebase
configuration, i.e. the one where all ENVs are unset, i.e. the features are disabled -
create the ENV-specific (e.g.
ELASTIC_ENABLED
)compose.<ENV>.yaml
file, e.g. backend v4 compose.elastic.yaml , with the additional/override config, specific to the enabled feature -
create a symlink from
.empty.yaml
to each
.compose.<ENV>.yaml
, e.g. here . This is used whenever theENV
is unset, as described in the next step -
use
compose.yaml
to merge thecompose*.yaml
files together, making sure to default to.compose.<ENV>.yaml
whenever theENV
is not set. See an example here -
if the service is another version of an existing one, e.g. v3 and v4 versions of the
backend
service, add the selective include in the parent compose.yaml, e.g. here - eventually, modify the compose workflow to add the toggle to the matrix. If the toggle depends on the changed files, remember to create the toggle configuration here and create the exclude rule in the workflow.
-
create a
-
eventually, add entrypoints for init logics, as described here , e.g. like here , including any ENVs specific logic. Remember to set the environment variable in the compose.yaml file.
General use of SciCat ¶
To use SciCat, please refer to the original documentation .