CI: Add rgm to drone (#66991)

* add drone stub that build grafana using 'grafana/build' (dagger)

---------

Co-authored-by: Ricky Whitaker <ricky.whitaker@grafana.com>

scripts/drone/rgm.star

@@ -0,0 +1,100 @@
+"""
+rgm uses 'github.com/grafana/grafana-build' to build Grafana on the following events:
+* A merge to main
+* A tag that begins with a 'v'
+"""
+
+load(
+    "scripts/drone/utils/utils.star",
+    "pipeline",
+)
+load(
+    "scripts/drone/vault.star",
+    "from_secret",
+    "rgm_destination",
+    "rgm_gcp_key_base64",
+    "rgm_github_token",
+)
+
+rgm_env_secrets = {
+    "GCP_KEY_BASE64": from_secret(rgm_gcp_key_base64),
+    "DESTINATION": from_secret(rgm_destination),
+    "GITHUB_TOKEN": from_secret(rgm_github_token),
+}
+
+def rgm_build(script = "drone_publish_main.sh"):
+    clone_step = {
+        "name": "clone-rgm",
+        "image": "alpine/git",
+        "commands": [
+            "git clone https://github.com/grafana/grafana-build.git rgm",
+        ],
+        "failure": "ignore",
+    }
+
+    rgm_build_step = {
+        "name": "rgm-build",
+        "image": "golang:1.20.3-alpine",
+        "commands": [
+            # the docker program is a requirement for running dagger programs
+            "apk update && apk add docker",
+            "export GRAFANA_DIR=$$(pwd)",
+            "cd rgm && ./scripts/{}".format(script),
+        ],
+        "environment": rgm_env_secrets,
+        # The docker socket is a requirement for running dagger programs
+        # In the future we should find a way to use dagger without mounting the docker socket.
+        "volumes": [{"name": "docker", "path": "/var/run/docker.sock"}],
+        "failure": "ignore",
+    }
+
+    return [
+        clone_step,
+        rgm_build_step,
+    ]
+
+def rgm_main():
+    trigger = {
+        "event": [
+            "push",
+        ],
+        "branch": "main",
+    }
+
+    return pipeline(
+        name = "[RGM] Build and upload a grafana.tar.gz to a prerelease bucket when merging to main",
+        edition = "all",
+        trigger = trigger,
+        steps = rgm_build(),
+    )
+
+def rgm_tag():
+    trigger = {
+        "event": {
+            "exclude": [
+                "promote",
+            ],
+        },
+        "ref": {
+            "include": [
+                "refs/tags/v*",
+            ],
+            "exclude": [
+                "refs/tags/*-cloud*",
+            ],
+        },
+    }
+
+    return pipeline(
+        name = "[RGM] Build and upload a grafana.tar.gz to a prerelease bucket when tagging",
+        edition = "all",
+        trigger = trigger,
+        steps = rgm_build(script = "drone_publish_tag.sh"),
+        depends_on = ["main-test-backend", "main-test-frontend"],
+    )
+
+def rgm():
+    return [
+        rgm_main(),
+        rgm_tag(),
+    ]

scripts/drone/vault.star

@@ -9,6 +9,10 @@ azure_sp_app_id = "azure_sp_app_id"
 azure_sp_app_pw = "azure_sp_app_pw"
 azure_tenant = "azure_tenant"
 
+rgm_gcp_key_base64 = "gcp_key_base64"
+rgm_destination = "destination"
+rgm_github_token = "github_token"
+
 def from_secret(secret):
     return {"from_secret": secret}
 
@@ -119,4 +123,19 @@ def secrets():
             "infra/data/ci/grafana-release-eng/enterprise2",
             "security_prefix",
         ),
+        vault_secret(
+            rgm_gcp_key_base64,
+            "infra/data/ci/grafana-release-eng/rgm",
+            "gcp_service_account_base64",
+        ),
+        vault_secret(
+            rgm_destination,
+            "infra/data/ci/grafana-release-eng/rgm",
+            "destination",
+        ),
+        vault_secret(
+            rgm_github_token,
+            "infra/data/ci/github/grafanabot",
+            "pat",
+        ),
     ]