Added target_branch for merge requests to allow creating custom scena…

…rios

README.md

@@ -72,6 +72,7 @@ commit_after_release: # define actions which have to happen after release and ou
 # branch with changes from commit_before_release and commit_after_release
 merge_request:
   enabled: True # if this is True merge request will be created
+  target_branch: hotfix-{VERSION} # optional property (default branch if empty) defining target branch for merge/pull request. Supports regexp
   title: Releasing version {VERSION} and preparation for next development cycle # you can use string predefined variables
   description: Hello world! I have just released {VERSION} # optional filed, you can use string predefined variables
   reviewers:
@@ -107,6 +108,30 @@ contains
 
 TODO
 
+## 🏴󠁣󠁤󠁥󠁱󠁿 variables
+
+**Use `{}` to evaluate variable to value f.e. `{FOOBAR}`**
+
+**hierarchy (from most important):**
+- predefined variables
+- custom variables
+- environment variables
+
+So, if there is predefined variable, you cannot override it or if same variable exists in environment,
+the value always will be as in predefined. If you define your custom variable and the same exists in environment,
+the value will be as defined by you. This hierarchy protects valhalla from errors and gives ability to extends
+and override values in custom use cases.
+
+### 🖖 predefined variables
+
+**Use `{}` to evaluate variable to value f.e. `{VERSION}`**
+
+|       name       |                                                                                                      description                                                                                                      |
+|:----------------:|:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------:|
+|    `VERSION`     |                                                                      value extracted from branch name, for `release-1.2.14` it will be `1.2.14`                                                                       |
+|  `VERSION_SLUG`  | value extracted from branch name and with everything except 0-9 and a-z replaced with -. No leading / trailing -, <br/>for `release-1.2.14` it will be `1-2-14`. Use in URLs, host names, domain names and file names |
+| `VALHALLA_TOKEN` |                                                                                   token passed to CI runner which execute this job                                                                                    |
+
 ### 🏭 custom variables
 
 You can define custom variables which can be used by defining them in strings using `{}`
@@ -123,17 +148,8 @@ merge_request:
 **It is really useful with `extends` mechanism, f.e. define general template with `variables`
 which will be overriden in child `valhalla.yml`.**
 
-### 🖖 predefined variables
-
-**Use `{}` to evaluate variable to value f.e. `{VERSION}`**
-
-|       name       |                                                                                                      description                                                                                                      |
-|:----------------:|:---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------:|
-|    `VERSION`     |                                                                      value extracted from branch name, for `release-1.2.14` it will be `1.2.14`                                                                       |
-|  `VERSION_SLUG`  | value extracted from branch name and with everything except 0-9 and a-z replaced with -. No leading / trailing -, <br/>for `release-1.2.14` it will be `1-2-14`. Use in URLs, host names, domain names and file names |
-| `VALHALLA_TOKEN` |                                                                                   token passed to CI runner which execute this job                                                                                    |
 
-### 🐛 Environment variables
+### 🐛 environment variables
 
 Valhalla allows you to use any variable defined in your environment system, it is useful f.e when you
 are using GitLab CI/CD and you want to

valhalla/ci_provider/gitlab/merge_request.py

@@ -21,18 +21,24 @@ def __init__(self):
         self.project = self.gl.projects.get(get_project_id(), lazy=True)
 
     def create(self, merge_request_config: MergeRequestConfig):
-        branch = os.environ.get('CI_COMMIT_BRANCH')
-        default_branch = os.environ.get('CI_DEFAULT_BRANCH')
+        source_branch = os.environ.get('CI_COMMIT_BRANCH')
 
-        info(f"Creating merge request from {branch} to {default_branch}")
+        if merge_request_config.target_branch:
+            info("Target branch for merge request:")
+            target_branch = resolve(merge_request_config.target_branch)
+        else:
+            info("target_branch not set, using default instead")
+            target_branch = os.environ.get('CI_DEFAULT_BRANCH')
+
+        info(f"Creating merge request from {source_branch} to {target_branch}")
 
         if not merge_request_config.description:
             info("merge_request.description not specified, using default")
 
         mr = self.project.mergerequests.create(
             {
-                'source_branch': branch,
-                'target_branch': default_branch,
+                'source_branch': source_branch,
+                'target_branch': target_branch,
                 'title': resolve(merge_request_config.title),
                 'description': resolve(get_description(merge_request_config.description)),
                 'remove_source_branch': True,

valhalla/common/get_config.py

@@ -6,8 +6,9 @@
 
 
 class MergeRequestConfig:
-    def __init__(self, enabled: bool, title: str, description: str, reviewers: List[str]):
+    def __init__(self, enabled: bool, target_branch: str, title: str, description: str, reviewers: List[str]):
         self.enabled = enabled
+        self.target_branch = target_branch
         self.title = title
         self.description = description
         self.reviewers = reviewers
@@ -16,6 +17,7 @@ def __repr__(self):
         return f"\n" \
                f"   MergeRequestConfig( \n" \
                f"     enabled={self.enabled} \n" \
+               f"     target_branch={self.target_branch} \n" \
                f"     title={self.title} \n" \
                f"     description={self.description} \n" \
                f"     reviewers={self.reviewers} \n" \
@@ -217,11 +219,13 @@ def get_merge_request_part(merge_request_dict: dict) -> MergeRequestConfig:
     enabled = str_to_bool(get_from_dict(merge_request_dict, 'enabled', True))
     merge_request_other_options_required = enabled
 
+    target_branch = get_from_dict(merge_request_dict, 'target_branch', False)
+
     title = get_from_dict(merge_request_dict, 'title', merge_request_other_options_required)
     description = get_from_dict(merge_request_dict, 'description', False)
 
     reviewers = get_from_dict(merge_request_dict, 'reviewers', False)
-    return MergeRequestConfig(enabled, title, description, reviewers)
+    return MergeRequestConfig(enabled, target_branch, title, description, reviewers)
 
 
 def str_to_bool(value: str) -> bool:

valhalla/common/resolver.py

@@ -32,6 +32,7 @@ def resolve(string: str):
         error("There is bug in valhalla! Please report it here: https://github.com/logchange/valhalla/issues")
         exit(1)
 
+    # hierarchy
     string = __resolve_predefined(string)
     string = __resolve_custom_variables(string)
     string = __resolve_from_env(string)