Add configurable dockerfile_path to applications

cabotage/celery/tasks/build.py

@@ -539,25 +539,25 @@ def file_path(filename):
             return os.path.join(image.application.subdirectory, filename)
         return filename
 
+    dockerfile_candidates = ["Dockerfile.cabotage", "Dockerfile"]
+    if image.application.dockerfile_path:
+        dockerfile_candidates = [image.application.dockerfile_path]
+
     dockerfile_name = None
-    dockerfile_body = _fetch_github_file(
-        image.application.github_repository,
-        image.commit_sha,
-        access_token=access_token,
-        filename=file_path("Dockerfile.cabotage"),
-    )
-    dockerfile_name = "Dockerfile.cabotage"
-    if dockerfile_body is None:
+    dockerfile_body = None
+    for candidate in dockerfile_candidates:
         dockerfile_body = _fetch_github_file(
             image.application.github_repository,
             image.commit_sha,
             access_token=access_token,
-            filename=file_path("Dockerfile"),
+            filename=file_path(candidate),
         )
-        dockerfile_name = "Dockerfile"
+        if dockerfile_body is not None:
+            dockerfile_name = candidate
+            break
     if dockerfile_body is None:
         raise BuildError(
-            "No Dockerfile.cabotage or Dockerfile found in root of "
+            f"No Dockerfile found in "
             f"{git_ref(image.application.github_repository, image.commit_sha)}"
         )
 

cabotage/client/templates/user/project_application_settings.html

@@ -25,6 +25,7 @@ <h2>Deployment Automation</h2>
         {{ form_field(form.github_repository) }}
         {{ form_field(form.auto_deploy_branch) }}
         {{ form_field(form.subdirectory) }}
+        {{ form_field(form.dockerfile_path) }}
         {{ form_field(form.github_repository_is_private) }}
         {{ form_field(form.github_app_installation_id) }}
         {{ form_field(form.github_environment_name ) }}

cabotage/server/models/projects.py

@@ -192,6 +192,11 @@ class Application(db.Model, Timestamp):
         nullable=True,
     )
 
+    dockerfile_path = db.Column(
+        db.Text(),
+        nullable=True,
+    )
+
     auto_deploy_branch = db.Column(
         db.Text(),
         nullable=True,

cabotage/server/user/forms.py

@@ -262,6 +262,14 @@ class EditApplicationSettingsForm(FlaskForm):
         "Subdirectory",
         description="Subdirectory to build out of",
     )
+    dockerfile_path = StringField(
+        "Dockerfile Path",
+        description="Custom path to Dockerfile (e.g. docker/Dockerfile), falls back to Dockerfile.cabotage then Dockerfile",
+        filters=[
+            (lambda x: x.strip() if (x and isinstance(x, str)) else x),
+            (lambda x: x if x else None),
+        ],
+    )
     github_app_installation_id = StringField(
         "GitHub Application Installation ID",
         description="Application Installation ID from GitHub",

migrations/versions/a1b2c3d4e5f6_add_dockerfile_path.py

@@ -0,0 +1,30 @@
+"""Add configurable dockerfile_path to applications
+
+Revision ID: a1b2c3d4e5f6
+Revises: c2ae2e19e1f2
+Create Date: 2026-02-17 20:30:00.000000
+
+"""
+
+from alembic import op
+import sqlalchemy as sa
+
+revision = "a1b2c3d4e5f6"
+down_revision = "c2ae2e19e1f2"
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.add_column(
+        "project_applications", sa.Column("dockerfile_path", sa.Text(), nullable=True)
+    )
+    op.add_column(
+        "project_applications_version",
+        sa.Column("dockerfile_path", sa.Text(), autoincrement=False, nullable=True),
+    )
+
+
+def downgrade():
+    op.drop_column("project_applications_version", "dockerfile_path")
+    op.drop_column("project_applications", "dockerfile_path")