pytest: add blackbox tests for reckless

A canned lightningd/plugins is used to test against. This allows faster
and more deterministic outcomes.

Changelog-None

tests/rkls_github_canned_server.py

@@ -0,0 +1,42 @@
+import flask
+import json
+import os
+
+
+def create_app(test_config=None):
+    app = flask.Flask(__name__)
+
+    @app.route("/api/repos/<github_user>/<github_repo>/contents/")
+    def github_plugins_repo_api(github_user, github_repo):
+        '''This emulates api.github.com calls to lightningd/plugins'''
+        user = flask.escape(github_user)
+        repo = flask.escape(github_repo)
+        canned_api = os.environ.get('REDIR_GITHUB') + f'/rkls_api_{user}_{repo}.json'
+        with open(canned_api, 'rb') as f:
+            canned_data = f.read(-1)
+        print(f'serving canned api data from {canned_api}')
+        resp = flask.Response(response=canned_data,
+                              headers={'Content-Type': 'application/json; charset=utf-8'})
+        return resp
+
+    @app.route("/api/repos/<github_user>/<github_repo>/git/trees/<plugin_name>")
+    def github_plugin_tree_api(github_user, github_repo, plugin_name):
+        dir_json = \
+            {
+                "url": f"https://api.github.com/repos/{github_user}/{github_repo}/git/trees/{plugin_name}",
+                "tree": []
+            }
+        # FIXME: Pull contents from directory
+        for file in os.listdir(f'tests/data/recklessrepo/{github_user}/{plugin_name}'):
+            dir_json["tree"].append({"path": file})
+        resp = flask.Response(response=json.dumps(dir_json),
+                              headers={'Content-Type': 'application/json; charset=utf-8'})
+        return resp
+
+    return app
+
+
+if __name__ == '__main__':
+    app = create_app()
+    with app.app_context():
+        app.run(debug=True)