Implement support for CI variables of type file

Add env_var and file as supported types for CI variables. Variables of
type file expose to users existing gitlab-runner behaviour - save
variable value into a temp file and set the path to this file in an ENV
var named after the variable key.

Resolves https://gitlab.com/gitlab-org/gitlab-ce/issues/46806.

1 files changed, 19 insertions, 12 deletions

diff --git a/doc/api/project_level_variables.md b/doc/api/project_level_variables.md
index 438bebe62f5..4a6f5624394 100644
--- a/doc/api/project_level_variables.md
+++ b/doc/api/project_level_variables.md
@@ -20,10 +20,12 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/a
 [
     {
         "key": "TEST_VARIABLE_1",
+        "variable_type": "env_var",
         "value": "TEST_1"
     },
     {
         "key": "TEST_VARIABLE_2",
+        "variable_type": "env_var",
         "value": "TEST_2"
     }
 ]
@@ -49,6 +51,7 @@ curl --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/a
 ```json
 {
     "key": "TEST_VARIABLE_1",
+    "variable_type": "env_var",
     "value": "TEST_1"
 }
 ```
@@ -61,12 +64,13 @@ Create a new variable.
 POST /projects/:id/variables
 ```
 
-| Attribute   | Type    | required | Description           |
-|-------------|---------|----------|-----------------------|
-| `id`        | integer/string | yes      | The ID of a project or [urlencoded NAMESPACE/PROJECT_NAME of the project](README.md#namespaced-path-encoding) owned by the authenticated user   |
-| `key`       | string  | yes      | The `key` of a variable; must have no more than 255 characters; only `A-Z`, `a-z`, `0-9`, and `_` are allowed |
-| `value`     | string  | yes      | The `value` of a variable |
-| `protected` | boolean | no       | Whether the variable is protected |
+| Attribute       | Type    | required | Description           |
+|-----------------|---------|----------|-----------------------|
+| `id`            | integer/string | yes      | The ID of a project or [urlencoded NAMESPACE/PROJECT_NAME of the project](README.md#namespaced-path-encoding) owned by the authenticated user   |
+| `key`           | string  | yes      | The `key` of a variable; must have no more than 255 characters; only `A-Z`, `a-z`, `0-9`, and `_` are allowed |
+| `value`         | string  | yes      | The `value` of a variable |
+| `variable_type` | string  | no       | The type of a variable. Available types are: `env_var` (default) and `file` |
+| `protected`     | boolean | no       | Whether the variable is protected |
 
 ```
 curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/1/variables" --form "key=NEW_VARIABLE" --form "value=new value"
@@ -76,6 +80,7 @@ curl --request POST --header "PRIVATE-TOKEN: <your_access_token>" "https://gitla
 {
     "key": "NEW_VARIABLE",
     "value": "new value",
+    "variable_type": "env_var",
     "protected": false
 }
 ```
@@ -88,12 +93,13 @@ Update a project's variable.
 PUT /projects/:id/variables/:key
 ```
 
-| Attribute   | Type    | required | Description             |
-|-------------|---------|----------|-------------------------|
-| `id`        | integer/string | yes      | The ID of a project or [urlencoded NAMESPACE/PROJECT_NAME of the project](README.md#namespaced-path-encoding) owned by the authenticated user     |
-| `key`       | string  | yes      | The `key` of a variable   |
-| `value`     | string  | yes      | The `value` of a variable |
-| `protected` | boolean | no       | Whether the variable is protected |
+| Attribute       | Type    | required | Description             |
+|-----------------|---------|----------|-------------------------|
+| `id`            | integer/string | yes      | The ID of a project or [urlencoded NAMESPACE/PROJECT_NAME of the project](README.md#namespaced-path-encoding) owned by the authenticated user     |
+| `key`           | string  | yes      | The `key` of a variable   |
+| `value`         | string  | yes      | The `value` of a variable |
+| `variable_type` | string  | no       | The type of a variable. Available types are: `env_var` (default) and `file` |
+| `protected`     | boolean | no       | Whether the variable is protected |
 
 ```
 curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab.example.com/api/v4/projects/1/variables/NEW_VARIABLE" --form "value=updated value"
@@ -103,6 +109,7 @@ curl --request PUT --header "PRIVATE-TOKEN: <your_access_token>" "https://gitlab
 {
     "key": "NEW_VARIABLE",
     "value": "updated value",
+    "variable_type": "env_var",
     "protected": true
 }
 ```