feat(manifest): override sidecar entrypoint and cmd (#2592)

This is done by following the same approach used to override default image settings.

Closes #2501

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internal/pkg/deploy/cloudformation/stack/transformers.go

@@ -72,6 +72,17 @@ func convertSidecar(s convertSidecarOpts) ([]*template.SidecarOpts, error) {
 		if err := validateSidecarDependsOn(*config, name, s); err != nil {
 			return nil, err
 		}
+
+		entrypoint, err := convertEntryPoint(config.EntryPoint)
+		if err != nil {
+			return nil, err
+		}
+
+		command, err := convertCommand(config.Command)
+		if err != nil {
+			return nil, err
+		}
+
 		mp := convertSidecarMountPoints(config.MountPoints)
 
 		sidecars = append(sidecars, &template.SidecarOpts{
@@ -86,6 +97,8 @@ func convertSidecar(s convertSidecarOpts) ([]*template.SidecarOpts, error) {
 			MountPoints:  mp,
 			DockerLabels: config.DockerLabels,
 			DependsOn:    config.DependsOn,
+			EntryPoint:   entrypoint,
+			Command:      command,
 		})
 	}
 	return sidecars, nil

internal/pkg/deploy/cloudformation/stack/transformers_test.go

@@ -26,6 +26,7 @@ func Test_convertSidecar(t *testing.T) {
 		inLabels          map[string]string
 		inDependsOn       map[string]string
 		inImg             manifest.Image
+		inImageOverride   manifest.ImageOverride
 		circDepContainers []string
 
 		wanted    *template.SidecarOpts
@@ -162,19 +163,96 @@ func Test_convertSidecar(t *testing.T) {
 				},
 			},
 		},
+		"do not specify image override": {
+			wanted: &template.SidecarOpts{
+				Name:       aws.String("foo"),
+				CredsParam: mockCredsParam,
+				Image:      mockImage,
+				Secrets:    mockMap,
+				Variables:  mockMap,
+				Essential:  aws.Bool(false),
+				EntryPoint: nil,
+				Command:    nil,
+			},
+		},
+		"specify entrypoint as a string": {
+			inImageOverride: manifest.ImageOverride{
+				EntryPoint: &manifest.EntryPointOverride{String: aws.String("bin")},
+			},
+
+			wanted: &template.SidecarOpts{
+				Name:       aws.String("foo"),
+				CredsParam: mockCredsParam,
+				Image:      mockImage,
+				Secrets:    mockMap,
+				Variables:  mockMap,
+				Essential:  aws.Bool(false),
+				EntryPoint: []string{"bin"},
+				Command:    nil,
+			},
+		},
+		"specify entrypoint as a string slice": {
+			inImageOverride: manifest.ImageOverride{
+				EntryPoint: &manifest.EntryPointOverride{StringSlice: []string{"bin", "arg"}},
+			},
+
+			wanted: &template.SidecarOpts{
+				Name:       aws.String("foo"),
+				CredsParam: mockCredsParam,
+				Image:      mockImage,
+				Secrets:    mockMap,
+				Variables:  mockMap,
+				Essential:  aws.Bool(false),
+				EntryPoint: []string{"bin", "arg"},
+				Command:    nil,
+			},
+		},
+		"specify command as a string": {
+			inImageOverride: manifest.ImageOverride{
+				Command: &manifest.CommandOverride{String: aws.String("arg")},
+			},
+
+			wanted: &template.SidecarOpts{
+				Name:       aws.String("foo"),
+				CredsParam: mockCredsParam,
+				Image:      mockImage,
+				Secrets:    mockMap,
+				Variables:  mockMap,
+				Essential:  aws.Bool(false),
+				EntryPoint: nil,
+				Command:    []string{"arg"},
+			},
+		},
+		"specify command as a string slice": {
+			inImageOverride: manifest.ImageOverride{
+				Command: &manifest.CommandOverride{StringSlice: []string{"arg1", "arg2"}},
+			},
+
+			wanted: &template.SidecarOpts{
+				Name:       aws.String("foo"),
+				CredsParam: mockCredsParam,
+				Image:      mockImage,
+				Secrets:    mockMap,
+				Variables:  mockMap,
+				Essential:  aws.Bool(false),
+				EntryPoint: nil,
+				Command:    []string{"arg1", "arg2"},
+			},
+		},
 	}
 	for name, tc := range testCases {
 		t.Run(name, func(t *testing.T) {
 			sidecar := map[string]*manifest.SidecarConfig{
 				"foo": {
-					CredsParam:   mockCredsParam,
-					Image:        mockImage,
-					Secrets:      mockMap,
-					Variables:    mockMap,
-					Essential:    aws.Bool(tc.inEssential),
-					Port:         tc.inPort,
-					DockerLabels: tc.inLabels,
-					DependsOn:    tc.inDependsOn,
+					CredsParam:    mockCredsParam,
+					Image:         mockImage,
+					Secrets:       mockMap,
+					Variables:     mockMap,
+					Essential:     aws.Bool(tc.inEssential),
+					Port:          tc.inPort,
+					DockerLabels:  tc.inLabels,
+					DependsOn:     tc.inDependsOn,
+					ImageOverride: tc.inImageOverride,
 				},
 			}
 			got, err := convertSidecar(convertSidecarOpts{

internal/pkg/manifest/workload.go

@@ -438,6 +438,7 @@ type SidecarConfig struct {
 	MountPoints  []SidecarMountPoint `yaml:"mount_points"`
 	DockerLabels map[string]string   `yaml:"labels"`
 	DependsOn    map[string]string   `yaml:"depends_on"`
+	ImageOverride `yaml:",inline"`
 }
 
 // TaskConfig represents the resource boundaries and environment variables for the containers in the task.

internal/pkg/template/workload.go

@@ -91,6 +91,8 @@ type SidecarOpts struct {
 	MountPoints  []*MountPoint
 	DockerLabels map[string]string
 	DependsOn    map[string]string
+	EntryPoint   []string
+	Command      []string
 }
 
 // StorageOpts holds data structures for rendering Volumes and Mount Points

site/content/docs/developing/sidecars.en.md

@@ -44,6 +44,12 @@ sidecars:
 
 ```
 
+{% include 'sidecar-config.en.md' %}
+
+<div class="separator"></div>
+
+## Example
+
 Below is an example of specifying the [nginx](https://www.nginx.com/) sidecar container in a load balanced web service manifest.
 
 ``` yaml

site/content/docs/include/sidecar-config.en.md

@@ -0,0 +1,52 @@
+
+<a id="port" href="#port" class="field">`port`</a> <span class="type">Integer</span>  
+Port of the container to expose (optional).
+
+<a id="image" href="#image" class="field">`image`</a> <span class="type">String</span>  
+Image URL for the sidecar container (required).
+
+<a id="credentialsParameter" href="#credentialsParameter" class="field">`credentialsParameter`</a> <span class="type">String</span>  
+ARN of the secret containing the private repository credentials (optional).
+
+<a id="variables" href="#variables" class="field">`variables`</a> <span class="type">Map</span>  
+Environment variables for the sidecar container (optional)
+
+<a id="secrets" href="#secrets" class="field">`secrets`</a> <span class="type">Map</span>  
+Secrets to expose to the sidecar container (optional)
+
+<a id="mount-points" href="#mount-points" class="field">`mount_points`</a> <span class="type">Array of Maps</span>  
+Mount paths for EFS volumes specified at the service level (optional).
+
+<span class="parent-field">mount_points.</span><a id="mount-points-source-volume" href="#mount-points-source-volume" class="field">`source_volume`</a> <span class="type">String</span>  
+Source volume to mount in this sidecar (required).
+
+<span class="parent-field">mount_points.</span><a id="mount-points-path" href="#mount-points-path" class="field">`path`</a> <span class="type">String</span>  
+The path inside the sidecar container at which to mount the volume (required).
+
+<span class="parent-field">mount_points.</span><a id="mount-points-read-only" href="#mount-points-read-only" class="field">`read_only`</a> <span class="type">Boolean</span>  
+Whether to allow the sidecar read-only access to the volume (default true).
+
+<a id="labels" href="#labels" class="field">`labels`</a> <span class="type">Map</span>  
+Docker labels to apply to this container (optional).
+
+<a id="depends_on" href="#depends_on" class="field">`depends_on`</a> <span class="type">Map</span>  
+Container dependencies to apply to this container (optional).
+
+<a id="entrypoint" href="#entrypoint" class="field">`entrypoint`</a> <span class="type">String or Array of Strings</span>  
+Override the default entrypoint in the sidecar.
+```yaml
+# String version.
+entrypoint: "/bin/entrypoint --p1 --p2"
+# Alteratively, as an array of strings.
+entrypoint: ["/bin/entrypoint", "--p1", "--p2"]
+```
+
+<a id="command" href="#command" class="field">`command`</a> <span class="type">String or Array of Strings</span>  
+Override the default command in the sidecar.
+
+```yaml
+# String version.
+command: ps au
+# Alteratively, as an array of strings.
+command: ["ps", "au"]
+```

templates/workloads/partials/cf/sidecars.yml

@@ -18,6 +18,7 @@
 - Name: {{$sidecar.Name}}
   Image: {{$sidecar.Image}}{{if $sidecar.Essential}}
   Essential: {{$sidecar.Essential}}{{end}}{{if $sidecar.Port}}
+{{include "image-overrides" . | indent 2}}
   PortMappings:
     - ContainerPort: {{$sidecar.Port}}{{if $sidecar.Protocol}}
       Protocol: {{$sidecar.Protocol}}{{end}}{{end}}