feat: allow write-back to actual kustomization files (#200)

* feat: allow write-back to actual kustomization files #199

* fix: was not handling default path correctly

default is the source path

* fix: sort imports

11 files changed, 435 insertions, 82 deletions

diff --git a/.github/actions/spelling/allow.txt b/.github/actions/spelling/allow.txt
index 72fa87a..787ae03 100644
--- a/.github/actions/spelling/allow.txt
+++ b/.github/actions/spelling/allow.txt
@@ -107,6 +107,7 @@ kubectl
 kubefake
 kubernetes
 Kustomization
+kustomization
 kustomize
 ldflags
 LDFLAGS
@@ -232,6 +233,7 @@ workflow
 workflows
 www
 yaml
+yml
 yourimage
 yourorg
 yourtoken
diff --git a/Dockerfile b/Dockerfile
index 3a01127..e3a51fe 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,6 +2,9 @@ FROM golang:1.14.13 AS builder
 
 RUN mkdir -p /src/argocd-image-updater
 WORKDIR /src/argocd-image-updater
+# cache dependencies as a layer for faster rebuilds
+COPY go.mod go.sum ./
+RUN go mod download
 COPY . .
 
 RUN mkdir -p dist && \
diff --git a/docs/configuration/applications.md b/docs/configuration/applications.md
index a53cfb8..00cd442 100644
--- a/docs/configuration/applications.md
+++ b/docs/configuration/applications.md
@@ -257,3 +257,32 @@ In order to test a template before configuring it for use in Image Updater,
 you can store the template you want to use in a temporary file, and then use
 the `argocd-image-updater template /path/to/file` command to render the
 template using pre-defined data and see its outcome on the terminal.
+
+#### Git Write-Back Target
+
+By default, git write-back will create or update `.argocd-source-<appName>.yaml`.
+
+If you are using Kustomize and want the image updates available for normal use with `kustomize`,
+you may set the `write-back-target` to `kustomization`. This method commits changes to the Kustomization
+file back to git as though you ran `kustomize edit set image`.
+
+```yaml
+argocd-image-updater.argoproj.io/write-back-method: git  # all git options are supported
+argocd-image-updater.argoproj.io/write-back-target: kustomization
+```
+
+You may also specify which kustomization to update with either a path relative to the project source path...
+
+```yaml
+argocd-image-updater.argoproj.io/write-back-target: "kustomization:../../base"
+# if the Application spec.source.path = config/overlays/foo, this would update the kustomization in config/base 
+```
+
+...or absolute with respect to the repository:
+
+```yaml
+# absolute paths start with /
+argocd-image-updater.argoproj.io/write-back-target: "kustomization:/config/overlays/bar"
+```
+
+Note that the Kustomization directory needs to be specified, not a file, like when using Kustomize.
diff --git a/go.mod b/go.mod
index a1760c7..36bb962 100644
--- a/go.mod
+++ b/go.mod
@@ -9,6 +9,8 @@ require (
 	github.com/argoproj/pkg v0.0.0-20200624215116-23e74cb168fe
 	github.com/docker/distribution v2.7.1+incompatible
 	github.com/docker/libtrust v0.0.0-20160708172513-aabc10ec26b7 // indirect
+	github.com/go-openapi/spec v0.19.5 // indirect
+	github.com/google/go-cmp v0.4.0 // indirect
 	github.com/gorilla/mux v1.7.4 // indirect
 	github.com/nokia/docker-registry-client v0.0.0-20201015093031-af1a6d3b4fb1
 	github.com/patrickmn/go-cache v2.1.0+incompatible
@@ -17,14 +19,18 @@ require (
 	github.com/spf13/cobra v1.0.0
 	github.com/stretchr/testify v1.6.1
 	go.uber.org/ratelimit v0.1.1-0.20201110185707-e86515f0dda9
-	golang.org/x/crypto v0.0.0-20200220183623-bac4c82f6975
-	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
+	golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9
+	golang.org/x/net v0.0.0-20201021035429-f5854403a974 // indirect
+	golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9
+	golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4 // indirect
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 	gopkg.in/src-d/go-git.v4 v4.13.1
-	gopkg.in/yaml.v2 v2.3.0
+	gopkg.in/yaml.v2 v2.4.0
 	k8s.io/api v1.18.8
 	k8s.io/apimachinery v1.18.8
 	k8s.io/client-go v11.0.1-0.20190816222228-6d55c1b1f1ca+incompatible
 	k8s.io/kubectl v1.18.8 // indirect
+	sigs.k8s.io/kustomize v2.0.3+incompatible
 )
 
 replace (
diff --git a/go.sum b/go.sum
index eaeabcd..bc7d46f 100644
--- a/go.sum
+++ b/go.sum
@@ -219,8 +219,9 @@ github.com/go-openapi/spec v0.0.0-20160808142527-6aced65f8501/go.mod h1:J8+jY1nA
 github.com/go-openapi/spec v0.17.0/go.mod h1:XkF/MOi14NmjsfZ8VtAKf8pIlbZzyoTvZsdfssdxcBI=
 github.com/go-openapi/spec v0.18.0/go.mod h1:XkF/MOi14NmjsfZ8VtAKf8pIlbZzyoTvZsdfssdxcBI=
 github.com/go-openapi/spec v0.19.2/go.mod h1:sCxk3jxKgioEJikev4fgkNmwS+3kuYdJtcsZsD5zxMY=
-github.com/go-openapi/spec v0.19.3 h1:0XRyw8kguri6Yw4SxhsQA/atC88yqrk0+G4YhI2wabc=
 github.com/go-openapi/spec v0.19.3/go.mod h1:FpwSN1ksY1eteniUU7X0N/BgJ7a4WvBFVA8Lj9mJglo=
+github.com/go-openapi/spec v0.19.5 h1:Xm0Ao53uqnk9QE/LlYV5DEU09UAgpliA85QoT9LzqPw=
+github.com/go-openapi/spec v0.19.5/go.mod h1:Hm2Jr4jv8G1ciIAo+frC/Ft+rR2kQDh8JHKHb3gWUSk=
 github.com/go-openapi/strfmt v0.17.0/go.mod h1:P82hnJI0CXkErkXi8IKjPbNBM6lV6+5pLP5l494TcyU=
 github.com/go-openapi/strfmt v0.18.0/go.mod h1:P82hnJI0CXkErkXi8IKjPbNBM6lV6+5pLP5l494TcyU=
 github.com/go-openapi/strfmt v0.19.0/go.mod h1:+uW+93UVvGGq2qGaZxdDeJqSAqBqBdl+ZPMF/cC8nDY=
@@ -303,8 +304,9 @@ github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ
 github.com/google/cadvisor v0.35.0/go.mod h1:1nql6U13uTHaLYB8rLS5x9IJc2qT6Xd/Tr1sTX6NE48=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.3.1 h1:Xye71clBPdm5HgqGwUkwhbynsUJZhDbS20FvLhQ2izg=
 github.com/google/go-cmp v0.3.1/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
+github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-github v17.0.0+incompatible/go.mod h1:zLgOLi98H3fifZn+44m+umXrS52loVEgC2AApnigrVQ=
 github.com/google/go-jsonnet v0.16.0/go.mod h1:sOcuej3UW1vpPTZOr8L7RQimqai1a57bt5j22LzGZCw=
 github.com/google/go-querystring v1.0.0/go.mod h1:odCYkC5MyYFN7vkCjXpyrEuKhc/BUO6wN/zVPAxq5ck=
@@ -658,8 +660,9 @@ golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529/go.mod h1:yigFU9vqHzYiE8U
 golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190617133340-57b3e21c3d56/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.0.0-20200220183623-bac4c82f6975 h1:/Tl7pH94bvbAAHBdZJT947M/+gp0+CqQXDtMRC0fseo=
 golang.org/x/crypto v0.0.0-20200220183623-bac4c82f6975/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 h1:psW17arqaxU48Z5kZ0CQnkZWQJsqcURM6tKiBApRjXI=
+golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/exp v0.0.0-20180321215751-8460e604b9de/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20180807140117-3d87b88a115f/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
@@ -698,8 +701,9 @@ golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLL
 golang.org/x/net v0.0.0-20190724013045-ca1201d0de80/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20191004110552-13f9640d40b9 h1:rjwSpXsdiK0dV8/Naq3kAw9ymfAeJIyd0upUIElB+lI=
 golang.org/x/net v0.0.0-20191004110552-13f9640d40b9/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974 h1:IX6qOQeG5uLjB/hjjwjedwfjND0hgjPMMyO1RoIXQNI=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190402181905-9f3314589c9a/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -712,8 +716,9 @@ golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208 h1:qwRHBd0NqMbJxfbotnDhm2ByMI1Shq4Y6oRJo21SGJA=
 golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9 h1:SQFwaSi55rU7vdNs9Yr0Z324VNlrF+0wMqRXT4St8ck=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20170830134202-bb24a47a89ea/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20171026204733-164713f0dfce/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -740,14 +745,17 @@ golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190826190057-c7b8b68b1456/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191022100944-742c48ecaeb7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20191026070338-33540a1f6037 h1:YyJpGZS1sBuBCzLAR1VEpK193GlqGZbnPFnPV/5Rsb4=
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4 h1:myAQVi0cGEoqQVR5POX+8RR2mrocKqNN1hmeMqhX27k=
+golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.0.0-20160726164857-2910a502d2bf/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.0.0-20170915090833-1cbadb444a80/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
+golang.org/x/text v0.3.3 h1:cokOdA+Jmi5PJGXLlLllQSgYigAEfHXJAERHVMaCc2k=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/time v0.0.0-20180412165947-fbb02b2291d2/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 h1:SvFZT6jyqRaOeXpc5h/JSfZenJ2O330aBsf7JfSUXmQ=
@@ -782,6 +790,9 @@ golang.org/x/tools v0.0.0-20190729092621-ff9f1409240a/go.mod h1:jcCCGcm9btYwXyDq
 golang.org/x/tools v0.0.0-20190909030654-5b82db07426d/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20190920225731-5eefd052ad72/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gonum.org/v1/gonum v0.0.0-20180816165407-929014505bf4/go.mod h1:Y+Yx5eoAFn32cQvJDxZx5Dpnq+c3wtXuadVZAcxbbBo=
 gonum.org/v1/gonum v0.0.0-20190331200053-3d26580ed485/go.mod h1:2ltnJ7xHfj0zHS40VVPYEAAMTa3ZGguvHGBSJeRWqE0=
 gonum.org/v1/gonum v0.6.2/go.mod h1:9mxDZsDKxgMAuccQkewq682L+0eCu4dCN2yonUJTCLU=
@@ -837,8 +848,9 @@ gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.1.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
diff --git a/pkg/argocd/git.go b/pkg/argocd/git.go
index dd80b00..1a70978 100644
--- a/pkg/argocd/git.go
+++ b/pkg/argocd/git.go
@@ -6,8 +6,15 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"path/filepath"
 	"text/template"
 
+	"sigs.k8s.io/kustomize/pkg/commands/kustfile"
+	"sigs.k8s.io/kustomize/pkg/fs"
+	image2 "sigs.k8s.io/kustomize/pkg/image"
+
+	"github.com/argoproj-labs/argocd-image-updater/pkg/image"
+
 	"github.com/argoproj-labs/argocd-image-updater/ext/git"
 	"github.com/argoproj-labs/argocd-image-updater/pkg/log"
 
@@ -51,25 +58,27 @@ func TemplateCommitMessage(tpl *template.Template, appName string, changeList []
 	return cmBuf.String()
 }
 
+type changeWriter func(app *v1alpha1.Application, wbc *WriteBackConfig, gitC git.Client) (err error, skip bool)
+
 // commitChanges commits any changes required for updating one or more images
 // after the UpdateApplication cycle has finished.
-func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig) error {
+func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig, write changeWriter) error {
 	creds, err := wbc.GetCreds(app)
 	if err != nil {
 		return fmt.Errorf("could not get creds for repo '%s': %v", app.Spec.Source.RepoURL, err)
 	}
-	tempRoot, err := ioutil.TempDir(os.TempDir(), fmt.Sprintf("git-%s", app.Name))
-	if err != nil {
-		return err
-	}
-	defer func() {
-		err := os.RemoveAll(tempRoot)
-		if err != nil {
-			log.Errorf("could not remove temp dir: %v", err)
-		}
-	}()
 	var gitC git.Client
 	if wbc.GitClient == nil {
+		tempRoot, err := ioutil.TempDir(os.TempDir(), fmt.Sprintf("git-%s", app.Name))
+		if err != nil {
+			return err
+		}
+		defer func() {
+			err := os.RemoveAll(tempRoot)
+			if err != nil {
+				log.Errorf("could not remove temp dir: %v", err)
+			}
+		}()
 		gitC, err = git.NewClientExt(app.Spec.Source.RepoURL, tempRoot, creds, false, false)
 		if err != nil {
 			return err
@@ -115,12 +124,49 @@ func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig) error {
 	if err != nil {
 		return err
 	}
+
+	if err, skip := write(app, wbc, gitC); err != nil {
+		return err
+	} else if skip {
+		return nil
+	}
+
+	commitOpts := &git.CommitOptions{}
+	if wbc.GitCommitMessage != "" {
+		cm, err := ioutil.TempFile("", "image-updater-commit-msg")
+		if err != nil {
+			return fmt.Errorf("cold not create temp file: %v", err)
+		}
+		log.Debugf("Writing commit message to %s", cm.Name())
+		err = ioutil.WriteFile(cm.Name(), []byte(wbc.GitCommitMessage), 0600)
+		if err != nil {
+			_ = cm.Close()
+			return fmt.Errorf("could not write commit message to %s: %v", cm.Name(), err)
+		}
+		commitOpts.CommitMessagePath = cm.Name()
+		_ = cm.Close()
+		defer os.Remove(cm.Name())
+	}
+
+	err = gitC.Commit("", commitOpts)
+	if err != nil {
+		return err
+	}
+	err = gitC.Push("origin", checkOutBranch, false)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func writeOverrides(app *v1alpha1.Application, _ *WriteBackConfig, gitC git.Client) (err error, skip bool) {
 	targetExists := true
-	targetFile := path.Join(tempRoot, app.Spec.Source.Path, fmt.Sprintf(".argocd-source-%s.yaml", app.Name))
+	targetFile := path.Join(gitC.Root(), app.Spec.Source.Path, fmt.Sprintf(".argocd-source-%s.yaml", app.Name))
 	_, err = os.Stat(targetFile)
 	if err != nil {
 		if !os.IsNotExist(err) {
-			return err
+			return
 		} else {
 			targetExists = false
 		}
@@ -128,7 +174,7 @@ func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig) error {
 
 	override, err := marshalParamsOverride(app)
 	if err != nil {
-		return fmt.Errorf("could not marshal parameters: %v", err)
+		return
 	}
 
 	// If the target file already exist in the repository, we will check whether
@@ -137,51 +183,96 @@ func commitChangesGit(app *v1alpha1.Application, wbc *WriteBackConfig) error {
 	if targetExists {
 		data, err := ioutil.ReadFile(targetFile)
 		if err != nil {
-			return err
+			return err, false
 		}
 		if string(data) == string(override) {
 			log.Debugf("target parameter file and marshaled data are the same, skipping commit.")
-			return nil
+			return nil, true
 		}
 	}
 
 	err = ioutil.WriteFile(targetFile, override, 0600)
 	if err != nil {
-		return err
+		return
 	}
 
 	if !targetExists {
 		err = gitC.Add(targetFile)
-		if err != nil {
-			return err
-		}
 	}
+	return
+}
 
-	commitOpts := &git.CommitOptions{}
-	if wbc.GitCommitMessage != "" {
-		cm, err := ioutil.TempFile("", "image-updater-commit-msg")
-		if err != nil {
-			return fmt.Errorf("cold not create temp file: %v", err)
-		}
-		log.Debugf("Writing commit message to %s", cm.Name())
-		err = ioutil.WriteFile(cm.Name(), []byte(wbc.GitCommitMessage), 0600)
-		if err != nil {
-			_ = cm.Close()
-			return fmt.Errorf("could not write commit message to %s: %v", cm.Name(), err)
-		}
-		commitOpts.CommitMessagePath = cm.Name()
-		_ = cm.Close()
-		defer os.Remove(cm.Name())
+var _ changeWriter = writeOverrides
+
+// writeKustomization writes any changes required for updating one or more images to a kustomization.yml
+func writeKustomization(app *v1alpha1.Application, wbc *WriteBackConfig, gitC git.Client) (err error, skip bool) {
+	if oldDir, err := os.Getwd(); err != nil {
+		return err, false
+	} else {
+		defer func() {
+			_ = os.Chdir(oldDir)
+		}()
 	}
 
-	err = gitC.Commit("", commitOpts)
+	base := filepath.Join(gitC.Root(), wbc.KustomizeBase)
+	if err := os.Chdir(base); err != nil {
+		return err, false
+	}
+
+	log.Infof("updating base %s", base)
+
+	kf, err := kustfile.NewKustomizationFile(fs.MakeRealFS())
 	if err != nil {
-		return err
+		return
 	}
-	err = gitC.Push("origin", checkOutBranch, false)
+	kustomization, err := kf.Read()
 	if err != nil {
-		return err
+		return
 	}
 
-	return nil
+Images:
+	for _, img := range app.Spec.Source.Kustomize.Images {
+		override := parseImageOverride(img)
+		for i, imgSet := range kustomization.Images {
+			if imgSet.Name == override.Name {
+				kustomization.Images[i] = override
+				continue Images
+			}
+		}
+		// wasn't an existing override, add one
+		kustomization.Images = append(kustomization.Images, override)
+	}
+
+	if err := kf.Write(kustomization); err != nil {
+		return err, false
+	}
+
+	return
 }
+
+func parseImageOverride(str v1alpha1.KustomizeImage) image2.Image {
+	// TODO is this a valid use? format could diverge
+	img := image.NewFromIdentifier(string(str))
+	tagName := ""
+	tagDigest := ""
+	if img.ImageTag != nil {
+		tagName = img.ImageTag.TagName
+		tagDigest = img.ImageTag.TagDigest
+	}
+	if img.RegistryURL != "" {
+		// NewFromIdentifier strips off the registry
+		img.ImageName = img.RegistryURL + "/" + img.ImageName
+	}
+	if img.ImageAlias == "" {
+		img.ImageAlias = img.ImageName
+		img.ImageName = "" // inside baseball (see return): name isn't changing, just tag, so don't write newName
+	}
+	return image2.Image{
+		Name:    img.ImageAlias,
+		NewName: img.ImageName,
+		NewTag:  tagName,
+		Digest:  tagDigest,
+	}
+}
+
+var _ changeWriter = writeKustomization
diff --git a/pkg/argocd/git_test.go b/pkg/argocd/git_test.go
index 94cabe0..503c8e5 100644
--- a/pkg/argocd/git_test.go
+++ b/pkg/argocd/git_test.go
@@ -9,7 +9,9 @@ import (
 	"github.com/argoproj-labs/argocd-image-updater/pkg/image"
 	"github.com/argoproj-labs/argocd-image-updater/pkg/tag"
 
+	"github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
 	"github.com/stretchr/testify/assert"
+	image2 "sigs.k8s.io/kustomize/pkg/image"
 )
 
 func Test_TemplateCommitMessage(t *testing.T) {
@@ -37,3 +39,50 @@ updates image bar/baz tag '2.0' to '2.1'
 		assert.Equal(t, exp, r)
 	})
 }
+
+func Test_parseImageOverride(t *testing.T) {
+	cases := []struct {
+		name     string
+		override v1alpha1.KustomizeImage
+		expected image2.Image
+	}{
+		{"tag update", "ghcr.io:1234/foo/foo:123", image2.Image{
+			Name:   "ghcr.io:1234/foo/foo",
+			NewTag: "123",
+		}},
+		{"image update", "ghcr.io:1234/foo/foo=ghcr.io:1234/bar", image2.Image{
+			Name:    "ghcr.io:1234/foo/foo",
+			NewName: "ghcr.io:1234/bar",
+		}},
+		{"update everything", "ghcr.io:1234/foo/foo=1234.foo.com:9876/bar:123", image2.Image{
+			Name:    "ghcr.io:1234/foo/foo",
+			NewName: "1234.foo.com:9876/bar",
+			NewTag:  "123",
+		}},
+		{"change registry and tag", "ghcr.io:1234/foo/foo=1234.dkr.ecr.us-east-1.amazonaws.com/bar:123", image2.Image{
+			Name:    "ghcr.io:1234/foo/foo",
+			NewName: "1234.dkr.ecr.us-east-1.amazonaws.com/bar",
+			NewTag:  "123",
+		}},
+		{"change only registry", "0001.dkr.ecr.us-east-1.amazonaws.com/bar=1234.dkr.ecr.us-east-1.amazonaws.com/bar", image2.Image{
+			Name:    "0001.dkr.ecr.us-east-1.amazonaws.com/bar",
+			NewName: "1234.dkr.ecr.us-east-1.amazonaws.com/bar",
+		}},
+		{"change image and set digest", "foo=acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", image2.Image{
+			Name:    "foo",
+			NewName: "acme/app",
+			Digest:  "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+		}},
+		{"set digest", "acme/app@sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855", image2.Image{
+			Name:   "acme/app",
+			Digest: "sha256:e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
+		}},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.expected, parseImageOverride(tt.override))
+		})
+	}
+
+}
diff --git a/pkg/argocd/update.go b/pkg/argocd/update.go
index 333d31a..e7d99c5 100644
--- a/pkg/argocd/update.go
+++ b/pkg/argocd/update.go
@@ -3,6 +3,7 @@ package argocd
 import (
 	"context"
 	"fmt"
+	"path/filepath"
 	"strings"
 	"sync"
 	"text/template"
@@ -16,10 +17,9 @@ import (
 	"github.com/argoproj-labs/argocd-image-updater/pkg/registry"
 	"github.com/argoproj-labs/argocd-image-updater/pkg/tag"
 
-	"gopkg.in/yaml.v2"
-
 	"github.com/argoproj/argo-cd/pkg/apiclient/application"
 	"github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
+	"gopkg.in/yaml.v2"
 )
 
 // Stores some statistics about the results of a run
@@ -64,6 +64,7 @@ type WriteBackConfig struct {
 	GitCommitUser    string
 	GitCommitEmail   string
 	GitCommitMessage string
+	KustomizeBase    string
 }
 
 // The following are helper structs to only marshal the fields we require
@@ -420,15 +421,12 @@ func getWriteBackConfig(app *v1alpha1.Application, kubeClient *kube.KubernetesCl
 	switch strings.TrimSpace(method) {
 	case "git":
 		wbc.Method = WriteBackGit
-		branch, ok := app.Annotations[common.GitBranchAnnotation]
-		if ok {
-			wbc.GitBranch = strings.TrimSpace(branch)
+		if target, ok := app.Annotations[common.WriteBackTargetAnnotation]; ok && strings.HasPrefix(target, common.KustomizationPrefix) {
+			wbc.KustomizeBase = parseTarget(target, app.Spec.Source.Path)
 		}
-		credsSource, err := getGitCredsSource(creds, kubeClient)
-		if err != nil {
-			return nil, fmt.Errorf("invalid git credentials source: %v", err)
+		if err := parseGitConfig(app, kubeClient, wbc, creds); err != nil {
+			return nil, err
 		}
-		wbc.GetCreds = credsSource
 	default:
 		return nil, fmt.Errorf("invalid update mechanism: %s", method)
 	}
@@ -436,6 +434,29 @@ func getWriteBackConfig(app *v1alpha1.Application, kubeClient *kube.KubernetesCl
 	return wbc, nil
 }
 
+func parseTarget(target string, sourcePath string) (kustomizeBase string) {
+	if target == common.KustomizationPrefix {
+		return filepath.Join(sourcePath, ".")
+	} else if base := target[len(common.KustomizationPrefix)+1:]; strings.HasPrefix(base, "/") {
+		return base[1:]
+	} else {
+		return filepath.Join(sourcePath, base)
+	}
+}
+
+func parseGitConfig(app *v1alpha1.Application, kubeClient *kube.KubernetesClient, wbc *WriteBackConfig, creds string) error {
+	branch, ok := app.Annotations[common.GitBranchAnnotation]
+	if ok {
+		wbc.GitBranch = strings.TrimSpace(branch)
+	}
+	credsSource, err := getGitCredsSource(creds, kubeClient)
+	if err != nil {
+		return fmt.Errorf("invalid git credentials source: %v", err)
+	}
+	wbc.GetCreds = credsSource
+	return nil
+}
+
 func commitChangesLocked(app *v1alpha1.Application, wbc *WriteBackConfig, state *SyncIterationState) error {
 	if wbc.RequiresLocking() {
 		lock := state.GetRepositoryLock(app.Spec.Source.RepoURL)
@@ -459,7 +480,11 @@ func commitChanges(app *v1alpha1.Application, wbc *WriteBackConfig) error {
 			return err
 		}
 	case WriteBackGit:
-		return commitChangesGit(app, wbc)
+		// if the kustomize base is set, the target is a kustomization
+		if wbc.KustomizeBase != "" {
+			return commitChangesGit(app, wbc, writeKustomization)
+		}
+		return commitChangesGit(app, wbc, writeOverrides)
 	default:
 		return fmt.Errorf("unknown write back method set: %d", wbc.Method)
 	}
diff --git a/pkg/argocd/update_test.go b/pkg/argocd/update_test.go
index b53387a..9f4aec9 100644
--- a/pkg/argocd/update_test.go
+++ b/pkg/argocd/update_test.go
@@ -3,6 +3,9 @@ package argocd
 import (
 	"errors"
 	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
 	"strings"
 	"testing"
 
@@ -1032,6 +1035,42 @@ func Test_GetWriteBackConfig(t *testing.T) {
 		assert.Equal(t, wbc.Method, WriteBackApplication)
 	})
 
+	t.Run("kustomization write-back config", func(t *testing.T) {
+		app := v1alpha1.Application{
+			ObjectMeta: v1.ObjectMeta{
+				Name: "testapp",
+				Annotations: map[string]string{
+					"argocd-image-updater.argoproj.io/image-list":        "nginx",
+					"argocd-image-updater.argoproj.io/write-back-method": "git",
+					"argocd-image-updater.argoproj.io/write-back-target": "kustomization:../bar",
+				},
+			},
+			Spec: v1alpha1.ApplicationSpec{
+				Source: v1alpha1.ApplicationSource{
+					RepoURL:        "https://example.com/example",
+					TargetRevision: "main",
+					Path:           "config/foo",
+				},
+			},
+			Status: v1alpha1.ApplicationStatus{
+				SourceType: v1alpha1.ApplicationSourceTypeKustomize,
+			},
+		}
+
+		argoClient := argomock.ArgoCD{}
+		argoClient.On("UpdateSpec", mock.Anything, mock.Anything).Return(nil, nil)
+
+		kubeClient := kube.KubernetesClient{
+			Clientset: fake.NewFakeKubeClient(),
+		}
+
+		wbc, err := getWriteBackConfig(&app, &kubeClient, &argoClient)
+		require.NoError(t, err)
+		require.NotNil(t, wbc)
+		assert.Equal(t, wbc.Method, WriteBackGit)
+		assert.Equal(t, wbc.KustomizeBase, "config/bar")
+	})
+
 	t.Run("Default write-back config - argocd", func(t *testing.T) {
 		app := v1alpha1.Application{
 			ObjectMeta: v1.ObjectMeta{
@@ -1366,9 +1405,8 @@ func Test_CommitUpdates(t *testing.T) {
 	}
 
 	t.Run("Good commit to target revision", func(t *testing.T) {
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
 			args.Assert(t, "main")
 		}).Return(nil)
@@ -1385,9 +1423,8 @@ func Test_CommitUpdates(t *testing.T) {
 	})
 
 	t.Run("Good commit to configured branch", func(t *testing.T) {
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
 			args.Assert(t, "mybranch")
 		}).Return(nil)
@@ -1407,9 +1444,8 @@ func Test_CommitUpdates(t *testing.T) {
 
 	t.Run("Good commit to default branch", func(t *testing.T) {
 		app := app.DeepCopy()
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
 			args.Assert(t, "mydefaultbranch")
 		}).Return(nil)
@@ -1427,11 +1463,67 @@ func Test_CommitUpdates(t *testing.T) {
 		assert.NoError(t, err)
 	})
 
+	t.Run("Good commit to kustomization", func(t *testing.T) {
+		app := app.DeepCopy()
+		app.Annotations[common.WriteBackTargetAnnotation] = "kustomization"
+		app.Spec.Source.Kustomize = &v1alpha1.ApplicationSourceKustomize{Images: v1alpha1.KustomizeImages{"foo=bar", "bar=baz:123"}}
+		gitMock, dir, cleanup := mockGit(t)
+		defer cleanup()
+		kf := filepath.Join(dir, "kustomization.yml")
+		assert.NoError(t, ioutil.WriteFile(kf, []byte(`
+kind: Kustomization
+apiVersion: kustomize.config.k8s.io/v1beta1
+`), os.ModePerm))
+
+		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
+			args.Assert(t, "mydefaultbranch")
+		}).Return(nil)
+		gitMock.On("Add", mock.Anything).Return(nil)
+		gitMock.On("Commit", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil)
+		gitMock.On("Push", mock.Anything, mock.Anything, mock.Anything).Return(nil)
+		gitMock.On("SymRefToBranch", mock.Anything).Return("mydefaultbranch", nil)
+		wbc, err := getWriteBackConfig(app, &kubeClient, &argoClient)
+		require.NoError(t, err)
+		wbc.GitClient = gitMock
+		app.Spec.Source.TargetRevision = "HEAD"
+		wbc.GitBranch = ""
+
+		err = commitChanges(app, wbc)
+		assert.NoError(t, err)
+		kust, err := ioutil.ReadFile(kf)
+		assert.NoError(t, err)
+		assert.YAMLEq(t, `
+kind: Kustomization
+apiVersion: kustomize.config.k8s.io/v1beta1
+images:
+  - name: foo
+    newName: bar
+  - name: bar
+    newName: baz
+    newTag: "123"
+`, string(kust))
+
+		// test the merge case too
+		app.Spec.Source.Kustomize.Images = v1alpha1.KustomizeImages{"foo:123", "bar=qux"}
+		err = commitChanges(app, wbc)
+		assert.NoError(t, err)
+		kust, err = ioutil.ReadFile(kf)
+		assert.NoError(t, err)
+		assert.YAMLEq(t, `
+kind: Kustomization
+apiVersion: kustomize.config.k8s.io/v1beta1
+images:
+  - name: foo
+    newTag: "123"
+  - name: bar
+    newName: qux
+`, string(kust))
+	})
+
 	t.Run("Good commit with author information", func(t *testing.T) {
 		app := app.DeepCopy()
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Run(func(args mock.Arguments) {
 			args.Assert(t, "mydefaultbranch")
 		}).Return(nil)
@@ -1526,9 +1618,8 @@ func Test_CommitUpdates(t *testing.T) {
 	})
 
 	t.Run("Cannot commit", func(t *testing.T) {
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Return(nil)
 		gitMock.On("Add", mock.Anything).Return(nil)
 		gitMock.On("Commit", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(fmt.Errorf("cannot commit"))
@@ -1542,9 +1633,8 @@ func Test_CommitUpdates(t *testing.T) {
 	})
 
 	t.Run("Cannot push", func(t *testing.T) {
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Return(nil)
 		gitMock.On("Add", mock.Anything).Return(nil)
 		gitMock.On("Commit", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil)
@@ -1559,9 +1649,8 @@ func Test_CommitUpdates(t *testing.T) {
 
 	t.Run("Cannot resolve default branch", func(t *testing.T) {
 		app := app.DeepCopy()
-		gitMock := &gitmock.Client{}
-		gitMock.On("Init").Return(nil)
-		gitMock.On("Fetch").Return(nil)
+		gitMock, _, cleanup := mockGit(t)
+		defer cleanup()
 		gitMock.On("Checkout", mock.Anything).Return(nil)
 		gitMock.On("Add", mock.Anything).Return(nil)
 		gitMock.On("Commit", mock.Anything, mock.Anything, mock.Anything, mock.Anything).Return(nil)
@@ -1577,3 +1666,39 @@ func Test_CommitUpdates(t *testing.T) {
 		assert.Errorf(t, err, "failed to resolve ref")
 	})
 }
+
+func Test_parseTarget(t *testing.T) {
+	cases := []struct {
+		name     string
+		expected string
+		target   string
+		path     string
+	}{
+		{"default", ".", "kustomization", ""},
+		{"explicit default", ".", "kustomization:.", "."},
+		{"default path, explicit target", ".", "kustomization:.", ""},
+		{"default target with path", "foo/bar", "kustomization", "foo/bar"},
+		{"default both", ".", "kustomization", ""},
+		{"absolute path", "foo", "kustomization:/foo", "bar"},
+		{"relative path", "bar/foo", "kustomization:foo", "bar"},
+		{"sibling path", "bar/baz", "kustomization:../baz", "bar/foo"},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.Equal(t, tt.expected, parseTarget(tt.target, tt.path))
+		})
+	}
+}
+
+func mockGit(t *testing.T) (gitMock *gitmock.Client, dir string, cleanup func()) {
+	dir, err := ioutil.TempDir("", "wb-kust")
+	assert.NoError(t, err)
+	gitMock = &gitmock.Client{}
+	gitMock.On("Root").Return(dir)
+	gitMock.On("Init").Return(nil)
+	gitMock.On("Fetch").Return(nil)
+	return gitMock, dir, func() {
+		_ = os.RemoveAll(dir)
+	}
+}
diff --git a/pkg/common/constants.go b/pkg/common/constants.go
index b42f1a9..6c7fec3 100644
--- a/pkg/common/constants.go
+++ b/pkg/common/constants.go
@@ -44,6 +44,8 @@ const (
 const (
 	WriteBackMethodAnnotation = ImageUpdaterAnnotationPrefix + "/write-back-method"
 	GitBranchAnnotation       = ImageUpdaterAnnotationPrefix + "/git-branch"
+	WriteBackTargetAnnotation = ImageUpdaterAnnotationPrefix + "/write-back-target"
+	KustomizationPrefix       = "kustomization"
 )
 
 // The default Git commit message's template
diff --git a/pkg/image/image_test.go b/pkg/image/image_test.go
index 3e74aaa..9cde998 100644
--- a/pkg/image/image_test.go
+++ b/pkg/image/image_test.go
@@ -54,6 +54,15 @@ func Test_ParseImageTags(t *testing.T) {
 		assert.Equal(t, "0.1", image.ImageTag.TagName)
 	})
 
+	t.Run("Parse valid image name with source name and registry info with port", func(t *testing.T) {
+		image := NewFromIdentifier("ghcr.io:4567/jannfis/orig-image=gcr.io:1234/jannfis/test-image:0.1")
+		assert.Equal(t, "gcr.io:1234", image.RegistryURL)
+		assert.Equal(t, "ghcr.io:4567/jannfis/orig-image", image.ImageAlias)
+		assert.Equal(t, "jannfis/test-image", image.ImageName)
+		require.NotNil(t, image.ImageTag)
+		assert.Equal(t, "0.1", image.ImageTag.TagName)
+	})
+
 	t.Run("Parse image without version source name and registry info", func(t *testing.T) {
 		image := NewFromIdentifier("jannfis/orig-image=gcr.io/jannfis/test-image")
 		assert.Equal(t, "gcr.io", image.RegistryURL)