Augment proxy rewrite

README.md

@@ -236,3 +236,19 @@ Using the command lines above without the `-s` flag for server will work on GKE.
 client_factory = TychoClientFactory ()
 client = client_factory.get_client ()
 ```
+
+### "proxy_rewrite" Feature Overview:
+
+The "proxy_rewrite" feature ensures system-wide consistency in handling service 
+locations, especially when interacting with higher-level reverse proxies. By def
+ining annotations in `service.yaml`, Ambassador's behavior is tailored, allowing
+the underlying service to perceive an altered path while maintaining a consistent
+location view at the system level.
+
+- **context.py**: Processes external specifications, capturing "proxy_rewrite" 
+directives, and transforms them into an internal representation.
+- **model.py**: Forms the structural foundation of the system, accurately reflecting
+the "proxy_rewrite" configurations and their implications.
+- **service.yaml**: Serves as a template for Kubernetes service definitions. When
+interpreted, it influences Ambassador's behavior using "proxy_rewrite" annotations,
+ensuring path and location consistency across the system.

tests/test_model.py

@@ -17,7 +17,7 @@ def test_system_model(request):
         "principal": {"username": "renci"},
         "service_account": "default",
         "conn_string": "",
-        "proxy_rewrite_rule": False,
+        "proxy_rewrite": { 'enabled': False },
         "containers": [
             {
                 "name": "nginx-container",

tycho/__init__.py

@@ -1 +1 @@
-VERSION = "1.16.1"
+VERSION = "1.17.1"

tycho/context.py

@@ -328,7 +328,9 @@ def start (self, principal, app_id, resource_request, host):
         spec["services"][app_id]["conn_string"] = conn_string
         """ Add a proxy rewrite rule """
         proxy_rewrite_rule = self.apps.get(app_id).get("proxy-rewrite-rule", False)
-        spec["services"][app_id]["proxy_rewrite_rule"] = proxy_rewrite_rule
+        proxy_rewrite = self.apps.get(app_id).get("proxy-rewrite", { "enabled":False, "target":None })
+        spec["services"][app_id]["proxy_rewrite"] = proxy_rewrite
+        if proxy_rewrite_rule: spec["services"][app_id]["proxy_rewrite"]["enabled"] = True
         """ Add gitea integration rule """
         gitea_integration = self.apps.get(app_id).get("gitea-integration", False)
         spec["services"][app_id]["gitea_integration"] = gitea_integration

tycho/model.py

@@ -164,7 +164,7 @@ def __repr__(self):
 
 class System:
     """ Distributed system of interacting containerized software. """
-    def __init__(self, config, name, principal, service_account, conn_string, proxy_rewrite_rule, containers, identifier,
+    def __init__(self, config, name, principal, service_account, conn_string, proxy_rewrite, containers, identifier,
                  gitea_integration, services={}, security_context={}, init_security_context={}):
         """ Construct a new abstract model of a system given a name and set of containers.
 
@@ -242,7 +242,7 @@ def __init__(self, config, name, principal, service_account, conn_string, proxy_
         self.init_memory = os.environ.get("TYCHO_APP_INIT_MEMORY", "250Mi")
         self.gpu_resource_name = os.environ.get("TYCHO_APP_GPU_RESOURCE_NAME", "nvidia.com/gpu")
         """Proxy rewrite rule for ambassador service annotations"""
-        self.proxy_rewrite_rule = proxy_rewrite_rule
+        self.proxy_rewrite = proxy_rewrite
         # """Flag for checking if an IRODS connection is enabled"""
         if os.environ.get("IROD_HOST") != None:
             logger.info("Irods host enabled")
@@ -452,7 +452,7 @@ def parse (config, name, principal, system, service_account, env={}, services={}
             "principal": principal,
             "service_account": service_account,
             "conn_string": spec.get("conn_string", ""),
-            "proxy_rewrite_rule": spec.get("proxy_rewrite_rule", False),
+            "proxy_rewrite": spec.get("proxy_rewrite", { 'target':None, 'enabled':False }),
             "containers": containers,
             "identifier": identifier,
             "gitea_integration": spec.get("gitea_integration", False),

tycho/template/service.yaml

@@ -32,8 +32,14 @@ metadata:
       headers:
           REMOTE_USER: {{system.username}}
       {% endif %}
-      {% if system.proxy_rewrite_rule == True %}
+      {% if system.proxy_rewrite.enabled == True %}
+      {% if system.proxy_rewrite.target == None %}
       rewrite: /private/{{system.system_name}}/{{system.username}}/{{system.identifier}}/{{system.conn_string}}
+      {% else %}
+      rewrite: {{ system.proxy_rewrite.target }}
+      add_response_headers:
+        X-Original-Path: /private/{{system.system_name}}/{{system.username}}/{{system.identifier}}/{{system.conn_string}}
+      {% endif %}
       {% endif %}
       retry_policy:
         retry_on: gateway-error