podman kube play/down --read from URL

`podman kube play` can create pods and containers from YAML
read from a URL poiniting to a YAML file.
For example: `podman kube play https://example.com/demo.yml`.
`podman kube down` can also teardown pods and containers created
from that YAML file by also reading YAML from a URL, provided the
YAML file the URL points to has not been changed or altered since
it was used to create pods and containers

Closes #14955
Signed-off-by: Niall Crowe <nicrowe@redhat.com>

cmd/podman/kube/down.go

@@ -19,7 +19,8 @@ var (
 		Args:              cobra.ExactArgs(1),
 		ValidArgsFunction: common.AutocompleteDefaultOneArg,
 		Example: `podman kube down nginx.yml
-   cat nginx.yml | podman kube down -`,
+   cat nginx.yml | podman kube down -
+   podman kube down https://example.com/nginx.yml`,
 	}
 )
 

cmd/podman/kube/play.go

@@ -5,7 +5,9 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net"
+	"net/http"
 	"os"
 	"strings"
 
@@ -13,6 +15,7 @@ import (
 	"github.com/containers/common/pkg/completion"
 	"github.com/containers/image/v5/types"
 	"github.com/containers/podman/v4/cmd/podman/common"
+	"github.com/containers/podman/v4/cmd/podman/parse"
 	"github.com/containers/podman/v4/cmd/podman/registry"
 	"github.com/containers/podman/v4/cmd/podman/utils"
 	"github.com/containers/podman/v4/libpod/define"
@@ -52,7 +55,8 @@ var (
 		ValidArgsFunction: common.AutocompleteDefaultOneArg,
 		Example: `podman kube play nginx.yml
   cat nginx.yml | podman kube play -
-  podman kube play --creds user:password --seccomp-profile-root /custom/path apache.yml`,
+  podman kube play --creds user:password --seccomp-profile-root /custom/path apache.yml
+  podman kube play https://example.com/nginx.yml`,
 	}
 )
 
@@ -67,7 +71,8 @@ var (
 		ValidArgsFunction: common.AutocompleteDefaultOneArg,
 		Example: `podman play kube nginx.yml
   cat nginx.yml | podman play kube -
-  podman play kube --creds user:password --seccomp-profile-root /custom/path apache.yml`,
+  podman play kube --creds user:password --seccomp-profile-root /custom/path apache.yml
+  podman play kube https://example.com/nginx.yml`,
 	}
 )
 
@@ -167,7 +172,7 @@ func playFlags(cmd *cobra.Command) {
 		_ = cmd.RegisterFlagCompletionFunc(contextDirFlagName, completion.AutocompleteDefault)
 
 		// NOTE: The service-container flag is marked as hidden as it
-		// is purely designed for running kube-play in systemd units.
+		// is purely designed for running kube-play or play-kube in systemd units.
 		// It is not something users should need to know or care about.
 		//
 		// Having a flag rather than an env variable is cleaner.
@@ -255,6 +260,7 @@ func play(cmd *cobra.Command, args []string) error {
 			return err
 		}
 	}
+
 	return kubeplay(reader)
 }
 
@@ -263,6 +269,7 @@ func playKube(cmd *cobra.Command, args []string) error {
 }
 
 func readerFromArg(fileName string) (*bytes.Reader, error) {
+	errURL := parse.ValidURL(fileName)
 	if fileName == "-" { // Read from stdin
 		data, err := io.ReadAll(os.Stdin)
 		if err != nil {
@@ -270,6 +277,19 @@ func readerFromArg(fileName string) (*bytes.Reader, error) {
 		}
 		return bytes.NewReader(data), nil
 	}
+	if errURL == nil {
+		response, err := http.Get(fileName)
+		if err != nil {
+			return nil, err
+		}
+		defer response.Body.Close()
+
+		data, err := ioutil.ReadAll(response.Body)
+		if err != nil {
+			return nil, err
+		}
+		return bytes.NewReader(data), nil
+	}
 	f, err := os.Open(fileName)
 	if err != nil {
 		return nil, err

docs/source/markdown/podman-kube-down.1.md

@@ -4,10 +4,14 @@
 podman-kube-down - Remove containers and pods based on Kubernetes YAML
 
 ## SYNOPSIS
-**podman kube down** *file.yml|-*
+**podman kube down** *file.yml|-|https://website.io/file.yml*
 
 ## DESCRIPTION
-**podman kube down** reads a specified Kubernetes YAML file, tearing down pods that were created by the `podman kube play` command via the same Kubernetes YAML file. Any volumes that were created by the previous `podman kube play` command remain intact. If the YAML file is specified as `-`, `podman kube down` reads the YAML from stdin.
+**podman kube down** reads a specified Kubernetes YAML file, tearing down pods that were created by the `podman kube play` command via the same Kubernetes YAML
+file. Any volumes that were created by the previous `podman kube play` command remain intact. If the YAML file is specified as `-`, `podman kube down` reads the
+YAML from stdin. The input can also be a URL that points to a YAML file such as https://podman.io/demo.yml. `podman kube down` will then teardown the pods and
+containers created by `podman kube play` via the same Kubernetes YAML from the URL. However, `podman kube down` will not work with a URL if the YAML file the URL
+points to has been changed or altered since the creation of the pods and containers using `podman kube play`.
 
 ## EXAMPLES
 
@@ -30,14 +34,31 @@ spec:
 Remove the pod and containers as described in the `demo.yml` file
 ```
 $ podman kube down demo.yml
+Pods stopped:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+Pods removed:
 52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
 ```
 
-Remove the pod and containers as described in the`demo.yml` file YAML sent to stdin
+Remove the pod and containers as described in the `demo.yml` file YAML sent to stdin
 ```
 $ cat demo.yml | podman kube play -
+Pods stopped:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+Pods removed:
 52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
 ```
 
+Remove the pods and containers as described in the `demo.yml` file YAML read from a URL
+```
+$ podman kube down https://podman.io/demo.yml
+Pods stopped:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+Pods removed:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+```
+`podman kube down` will not work with a URL if the YAML file the URL points to has been changed
+or altered since it was used to create the pods and containers.
+
 ## SEE ALSO
 **[podman(1)](podman.1.md)**, **[podman-kube(1)](podman-kube.1.md)**, **[podman-kube-play(1)](podman-kube-play.1.md)**, **[podman-kube-generate(1)](podman-kube-generate.1.md)**, **[containers-certs.d(5)](https://github.com/containers/image/blob/main/docs/containers-certs.d.5.md)**

docs/source/markdown/podman-kube-play.1.md.in

@@ -4,13 +4,14 @@
 podman-kube-play - Create containers, pods and volumes based on Kubernetes YAML
 
 ## SYNOPSIS
-**podman kube play** [*options*] *file.yml|-*
+**podman kube play** [*options*] *file.yml|-|https://website.io/file.yml*
 
 ## DESCRIPTION
 **podman kube play** will read in a structured file of Kubernetes YAML.  It will then recreate the containers, pods or volumes described in the YAML.  Containers within a pod are then started and the ID of the new Pod or the name of the new Volume is output. If the yaml file is specified as "-" then `podman kube play` will read the YAML file from stdin.
 Using the `--down` command line option, it is also capable of tearing down the pods created by a previous run of `podman kube play`.
 Using the `--replace` command line option, it will tear down the pods(if any) created by a previous run of `podman kube play` and recreate the pods with the Kubernetes YAML file.
 Ideally the input file would be one created by Podman (see podman-kube-generate(1)).  This would guarantee a smooth import and expected results.
+The input can also be a URL that points to a YAML file such as https://podman.io/demo.yml. `podman kube play` will read the YAML from the URL and create pods and containers from it.
 
 Currently, the supported Kubernetes kinds are:
 - Pod
@@ -300,8 +301,23 @@ Create a pod connected to two networks (called net1 and net2) with a static ip
 $ podman kube play demo.yml --network net1:ip=10.89.1.5 --network net2:ip=10.89.10.10
 52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
 ```
-
 Please take into account that networks must be created first using podman-network-create(1).
 
+Create and teardown from a URL pointing to a YAML file
+```
+$ podman kube play https://podman.io/demo.yml
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+
+$ podman kube play --down https://podman.io/demo.yml
+Pods stopped:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+Pods removed:
+52182811df2b1e73f36476003a66ec872101ea59034ac0d4d3a7b40903b955a6
+```
+`podman kube play --down` will not work with a URL if the YAML file the URL points to
+has been changed or altered.
+
+
+
 ## SEE ALSO
 **[podman(1)](podman.1.md)**, **[podman-kube(1)](podman-kube.1.md)**, **[podman-kube-down(1)](podman-kube-down.1.md)**, **[podman-network-create(1)](podman-network-create.1.md)**, **[podman-kube-generate(1)](podman-kube-generate.1.md)**, **[containers-certs.d(5)](https://github.com/containers/image/blob/main/docs/containers-certs.d.5.md)**

test/system/700-play.bats

@@ -361,3 +361,28 @@ status: {}
     run_podman pod rm -a
     run_podman rm -a
 }
+
+@test "podman kube play - URL" {
+    TESTDIR=$PODMAN_TMPDIR/testdir
+    mkdir -p $TESTDIR
+    echo "$testYaml" | sed "s|TESTDIR|${TESTDIR}|g" > $PODMAN_TMPDIR/test.yaml
+
+    HOST_PORT=$(random_free_port)
+    SERVER=http://127.0.0.1:$HOST_PORT
+
+    run_podman run -d --name myyaml -p "$HOST_PORT:80" \
+    -v $PODMAN_TMPDIR/test.yaml:/var/www/testpod.yaml:Z \
+    -w /var/www \
+    $IMAGE /bin/busybox-extras httpd -f -p 80
+
+    run_podman kube play $SERVER/testpod.yaml
+    run_podman inspect test_pod-test --format "{{.State.Running}}"
+    is "$output" "true"
+    run_podman kube down $SERVER/testpod.yaml
+    run_podman 125 inspect test_pod-test
+    is "$output" ".*Error: inspecting object: no such object: \"test_pod-test\""
+
+    run_podman pod rm -a -f
+    run_podman rm -a -f
+    run_podman rm -f -t0 myyaml
+}