Merge ~athos-ribeiro/ubuntu-docker-images/+git/postgresql:13-21.04-fix-docs into ~ubuntu-docker-images/ubuntu-docker-images/+git/postgresql:13-21.04

[Athos Ribeiro]

Fix documentation metadata on current hirsute image.

After https://code.launchpad.net/~canonical-server/ubuntu-docker-images/+git/postgresql/+merge/403515 was filed, we realized we were using the wrong branch for this OCI. When pointing to the correct branch, we added a regression in the docs, which were outdated in the new build branch.

This updates the documentation in such branch.

[Sergio Durigan Junior (sergiodj)]

Thanks, Athos.

21.04 is not an LTS release, so the docs will need to be fixed/regenerated (I'm leaving a comment below).

Other than that, this MP LGTM. Feel free to merge it once the LTS nit has been fixed.

review: Approve

[Athos Ribeiro (athos-ribeiro)]

Thanks, Sergio.

I fixed the issue and merged the MP!

diff --git a/HACKING.md b/HACKING.md
index ba09252..ce674bb 100644
--- a/HACKING.md
+++ b/HACKING.md
@@ -1,7 +1,7 @@
 # Contributing
 
 In Ubuntu, Postgres is available as a `.deb` package.  For this reason,
-this image was built by installing the Postgres Ubuntu 20.04 LTS package
+this image was built by installing the Postgres Ubuntu 21.04 package
 inside a docker container.
 
 In order to contribute to the Postgres OCI image, do the following:
@@ -50,6 +50,6 @@ The repository containing the templates is located at:
 https://code.launchpad.net/~canonical-server/ubuntu-docker-images/+git/templates
 
 The specific data for this image's template can be found inside the
-`data/` directory.
+`data/` directory, in the image's own repository.
 
 
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..ffaf5cb
--- /dev/null
+++ b/README.md
@@ -0,0 +1,114 @@
+# Postgres | Ubuntu
+
+Current Postgres Docker Image from Ubuntu. Receives security updates and rolls to newer Postgres or Ubuntu LTS. This repository is exempted from per-user rate limits. For [LTS Docker Image](https://ubuntu.com/security/docker-images) versions of this image, see `lts/postgres`. 
+
+
+## About Postgres
+
+PostgreSQL is a powerful, open source object-relational database system. It is fully ACID compliant, has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It includes most SQL:2008 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports storage of binary large objects, including pictures, sounds, or video. It has native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, ODBC, among others, and exceptional documentation. Read more on the [PostgreSQL website](https://www.postgresql.org/docs/).
+
+
+## Tags and Architectures
+![LTS](https://assets.ubuntu.com/v1/0a5ff561-LTS%402x.png?h=17)
+Up to 5 years free security maintenance `from lts/postgres`.
+
+![ESM](https://assets.ubuntu.com/v1/572f3fbd-ESM%402x.png?h=17)
+Up to 10 years customer security maintenance `from store/canonical/postgres`.
+
+_Tags in italics are not available in ubuntu/postgres but are shown here for completeness._
+
+| Channel Tag | | | Currently | Architectures |
+|---|---|---|---|---|
+| **`13.4-21.04_beta`**    | | | Postgres 13.4 on Ubuntu 21.04 | `amd64`, `arm64`, `s390x` |
+| _`track_risk`_ |
+
+Channel tag shows the most stable channel for that track ordered `stable`, `candidate`, `beta`, `edge`. More risky channels are always implicitly available. So if `beta` is listed, you can also pull `edge`. If `candidate` is listed, you can pull `beta` and `edge`. When `stable` is listed, all four are available. Images are guaranteed to progress through the sequence `edge`, `beta`, `candidate` before `stable`.
+
+
+## Usage
+
+Launch this image locally:
+
+```sh
+docker run -d --name postgres-container -e TZ=UTC -p 30432:5432 -e POSTGRES_PASSWORD=My:s3Cr3t/ ubuntu/postgres:13.4-21.04_beta
+```
+Access your PostgreSQL server at `localhost:30432`.
+
+#### Parameters
+
+| Parameter | Description |
+|---|---|
+| `-e TZ=UTC` | Timezone. |
+| `-e POSTGRES_PASSWORD=secret` | Set the password for the superuser which is `postgres` by default. Bear in mind that to connect to the database in the same host the password is not needed but to access it via an external host (for instance another container) the password is needed. This option is **mandatory** and **must not be empty**. |
+| `-e POSTGRES_USER=john` | Create a new user with superuser privileges. This is used in conjunction with `POSTGRES_PASSWORD`. |
+| `-e POSTGRES_DB=db_test` | Set the name of the default database. |
+| `-e POSTGRES_INITDB_ARGS="--data-checksums"` | Pass arguments to the `postgres initdb` call. |
+| `-e POSTGRES_INITDB_WALDIR=/path/to/location` | Set the location of the Postgres transaction log. By default it is stored in a subdirectory of the main Postgres data folder (`PGDATA`). |
+| `-e POSTGRES_HOST_AUTH_METHOD=trust` | Set the `auth-method` for `host` connections for `all` databases, `all` users, and `all` addresses. The following will be added to the `pg_hba.conf` if this option is passed: `host all all all $POSTGRES_HOST_AUTH_METHOD`. |
+| `-e PGDATA=/path/to/location` | Set the location of the database files. The default is `/var/lib/postgresql/data`. |
+| `-p 30432:5432` | Expose Postgres on `localhost:30432`. |
+| `-v /path/to/postgresql.conf:/etc/postgresql/postgresql.conf` | Local [configuration file](https://www.postgresql.org/docs/12/index.html) `postgresql.conf` (try [this example](https://git.launchpad.net/~canonical-server/ubuntu-docker-images/+git/postgresql/plain/examples/config/postgresql.conf)). |
+| `-v /path/to/persisted/data:/var/lib/postgresql/data` | Persist data instead of initializing a new database every time you launch a new container. |
+
+#### Initialization Scripts
+
+One can also add initialization scripts to their containers. This includes `*.sql`, `.sql.gz`, and `*.sh` scripts, and you just need to put them inside the  `/docker-entrypoint-initdb.d` directory inside the container. After Postgres initialization is done and the default database and user are created, the scripts are executed in the following order:
+
+* Run any `*.sql` files in alphabetically order. It will be executed with `POSTGRES_USER`.
+* Run any executable `*.sh` scripts in alphabetically order.
+* Source any non-executable `*.sh` scripts in alphabetically order.
+
+All of this is done before the Postgres service is started. Keep in mind if your `PGDATA` directory is not empty (contains pre-existing database) they will be left untouched.
+
+
+#### Testing/Debugging
+
+To debug the container:
+
+```sh
+docker logs -f postgres-container
+```
+
+To get an interactive shell:
+
+```sh
+docker exec -it postgres-container /bin/bash
+```
+
+This image also includes the `psql` client for interactive container use:
+
+```sh
+$ docker network create postgres-network
+$ docker network connect postgres-network postgres-container
+$ docker run -it --rm --network postgres-network ubuntu/postgres:13.4-21.04_beta psql -h postgres-container -U postgres
+```
+The password will be asked and you can enter `My:s3Cr3t/`. Now, you are logged in and can enjoy your new instance.
+
+## Deploy with Kubernetes
+
+Works with any Kubernetes; if you don't have one, we recommend you [install MicroK8s](https://microk8s.io/) and `microk8s.enable dns storage` then `snap alias microk8s.kubectl kubectl`.
+
+Download
+[postgresql.conf](https://git.launchpad.net/~canonical-server/ubuntu-docker-images/+git/postgresql/plain/examples/config/postgresql.conf) and
+[postgres-deployment.yml](https://git.launchpad.net/~canonical-server/ubuntu-docker-images/+git/postgresql/plain/examples/postgres-deployment.yml) and set `containers.postgres.image` in `postgres-deployment.yml` to your chosen channel tag (e.g. `ubuntu/postgres:13.4-21.04_beta`), then:
+
+```sh
+kubectl create configmap postgres-config --from-file=main-config=postgresql.conf
+kubectl apply -f postgres-deployment.yml
+```
+
+You will now be able to connect to the Postgres server on `localhost:30306`.
+
+## Bugs and feature requests
+
+If you find a bug in our image or want to request a specific feature, please file a bug here:
+
+[https://bugs.launchpad.net/ubuntu-docker-images/+filebug](https://bugs.launchpad.net/ubuntu-docker-images/+filebug)
+
+Please title the bug "`postgres: <issue summary>`". Make sure to include the digest of the image you are using, from:
+
+```sh
+docker images --no-trunc --quiet ubuntu/postgres:<tag>
+```
+
+
diff --git a/data/postgres.yaml b/data/postgres.yaml
index a772c6b..fa84d0a 100644
--- a/data/postgres.yaml
+++ b/data/postgres.yaml
@@ -3,8 +3,8 @@ main: true
 repo: postgres
 description: >
   PostgreSQL is a powerful, open source object-relational database system. It is fully ACID compliant, has full support for foreign keys, joins, views, triggers, and stored procedures (in multiple languages). It includes most SQL:2008 data types, including INTEGER, NUMERIC, BOOLEAN, CHAR, VARCHAR, DATE, INTERVAL, and TIMESTAMP. It also supports storage of binary large objects, including pictures, sounds, or video. It has native programming interfaces for C/C++, Java, .Net, Perl, Python, Ruby, Tcl, ODBC, among others, and exceptional documentation. Read more on the [PostgreSQL website](https://www.postgresql.org/docs/).
-version: "12.4"
-base: Ubuntu 20.04 LTS
+version: "13.4"
+base: Ubuntu 21.04
 architectures:
   - amd64
   - arm64