feat(nodes): add prompt template node with variable substitution

nodes/src/nodes/prompt_template/IGlobal.py

@@ -0,0 +1,44 @@
+# =============================================================================
+# MIT License
+# Copyright (c) 2026 Aparavi Software AG
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+# =============================================================================
+
+from rocketlib import IGlobalBase, OPEN_MODE
+from ai.common.config import Config
+
+
+class IGlobal(IGlobalBase):
+    config = None
+
+    def beginGlobal(self):
+        if self.IEndpoint.endpoint.openMode == OPEN_MODE.CONFIG:
+            pass
+        else:
+            import os
+            from depends import depends  # type: ignore
+
+            requirements = os.path.dirname(os.path.realpath(__file__)) + '/requirements.txt'
+            depends(requirements)
+
+            self.config = Config.getNodeConfig(self.glb.logicalType, self.glb.connConfig)
+
+    def endGlobal(self):
+        self.config = None

nodes/src/nodes/prompt_template/IInstance.py

@@ -0,0 +1,85 @@
+# =============================================================================
+# MIT License
+# Copyright (c) 2026 Aparavi Software AG
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+# =============================================================================
+
+from rocketlib import IInstanceBase
+from .IGlobal import IGlobal
+from .template_engine import render
+from ai.common.schema import Question
+from rocketlib import debug, Entry
+
+
+class IInstance(IInstanceBase):
+    IGlobal: IGlobal
+
+    def __init__(self):
+        """Initialize the prompt template node instance state."""
+        super().__init__()
+        self.collected_text: list[str] = []
+        self.question = Question()
+
+    def open(self, entry: Entry):
+        pass
+
+    def _get_template_context(self) -> dict:
+        """Build the context dictionary for template rendering."""
+        config = self.IGlobal.config
+        if config is None:
+            config = {}
+        raw_variables = config.get('variables', {})
+        variables = dict(raw_variables) if isinstance(raw_variables, dict) else {}
+
+        # Add collected text as 'input' if available
+        if self.collected_text:
+            variables.setdefault('input', '\n'.join(self.collected_text))
+
+        return variables
+
+    def writeQuestions(self, question: Question):
+        for q in question.questions:
+            self.question.addQuestion(q.text)
+
+    def writeText(self, text: str):
+        self.collected_text.append(text)
+
+    def closing(self):
+        try:
+            config = self.IGlobal.config or {}
+            template = config.get('template', '{{input}}')
+            context = self._get_template_context()
+
+            # Render questions with full context now that all text has arrived
+            if self.question.questions:
+                rendered_question = Question()
+                for q in self.question.questions:
+                    context['question'] = q.text
+                    rendered = render(template, context)
+                    rendered_question.addQuestion(rendered)
+                self.instance.writeQuestions(rendered_question)
+            # If we only have text input, render and output as text
+            elif self.collected_text:
+                rendered = render(template, context)
+                self.instance.writeText(rendered)
+
+        except Exception as e:
+            debug(f'Error in prompt_template node: {e}')
+            raise

nodes/src/nodes/prompt_template/__init__.py

@@ -0,0 +1,27 @@
+# =============================================================================
+# MIT License
+# Copyright (c) 2026 Aparavi Software AG
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+# =============================================================================
+
+from .IGlobal import IGlobal
+from .IInstance import IInstance
+
+__all__ = ['IGlobal', 'IInstance']

nodes/src/nodes/prompt_template/requirements.txt

@@ -0,0 +1 @@
+# No external dependencies — stdlib only

nodes/src/nodes/prompt_template/services.json

@@ -0,0 +1,195 @@
+{
+	//
+	// Required:
+	//		The displayable name of this node
+	//
+	"title": "Prompt Template",
+	//
+	// Required:
+	//		The protocol is the endpoint protocol
+	//
+	"protocol": "prompt-template://",
+	//
+	// Required:
+	//		Class type of the node - what it does
+	//
+	"classType": [
+		"text"
+	],
+	//
+	// Required:
+	//		Capabilities are flags that change the behavior of the underlying
+	//		engine
+	//
+	"capabilities": ["experimental"],
+	//
+	// Optional:
+	//		Register is either filter, endpoint or ignored if not specified. If the
+	//		type is specified, a factory is registered of that given type
+	//
+	"register": "filter",
+	//
+	// Optional:
+	//		The node is the actual pyhsical node to instantiate - if
+	//		not specified, the protocol will be used
+	//
+	"node": "python",
+	//
+	// Optional:
+	//		The path is the executable/script code - it is node dependent
+	// 		and is optional for most node
+	//
+	"path": "nodes.prompt_template",
+	//
+	// Required:
+	//		The prefix map when added/removed when convertting URLs <=> paths
+	//
+	"prefix": "prompt_template",
+	//
+	// Optional:
+	//		Description to of this driver
+	//
+	"description": [
+		"A transformation component that renders prompt templates with dynamic ",
+		"variable substitution. Supports {{variable}} placeholders resolved from ",
+		"pipeline context, built-in helpers ({{now}}, {{uuid}}, {{random}}), ",
+		"conditional sections ({% if var %}...{% endif %}), loop support ",
+		"({% for item in list %}...{% endfor %}), and escape sequences for ",
+		"literal braces. Implemented with stdlib only — no Jinja2 dependency."
+	],
+	//
+	// Optional:
+	//	  The icon is the icon to display in the UI for this node
+	//
+	"icon": "prompt.svg",
+	//
+	// Optional:
+	//	 The tile is the displayable name of this node
+	//
+	"tile": [],
+	//
+	//	Optional:
+	//		As a pipe component, define what this pipe component takes
+	//		and what it produces
+	//
+	"lanes": {
+		"text": ["text"],
+		"questions": ["questions"]
+	},
+	"input": [
+		{
+			"lane": "text",
+			"description": "Text input - used as context variables for template rendering",
+			"output": [
+				{
+					"lane": "text",
+					"description": "Rendered template output as text"
+				}
+			]
+		},
+		{
+			"lane": "questions",
+			"description": "Questions input - question text is rendered through the template",
+			"output": [
+				{
+					"lane": "questions",
+					"description": "Questions with template-rendered text"
+				}
+			]
+		}
+	],
+	//
+	//	Optional:
+	//		Profile section are configuration options used by the driver
+	//		itself
+	//
+	"preconfig": {
+		"default": "default",
+		"profiles": {
+			"default": {
+				"template": "{{input}}",
+				"variables": {}
+			}
+		}
+	},
+	//
+	//	Test configuration for automated node testing
+	//
+	"test": {
+		"profiles": ["default"],
+		"cases": [
+			{
+				"questions": {
+					"questions": [{"text": "Hello world"}]
+				},
+				"expect": {
+					"questions": {
+						"notEmpty": true
+					}
+				}
+			},
+			{
+				"config": {
+					"template": "Summarize the following: {{input}}",
+					"variables": {"input": "The quick brown fox jumps over the lazy dog."}
+				},
+				"questions": {
+					"questions": [{"text": "test prompt"}]
+				},
+				"expect": {
+					"questions": {
+						"notEmpty": true,
+						"contains": "Summarize the following:"
+					}
+				}
+			},
+			{
+				"config": {
+					"template": "Q={{question}} | I={{input}}",
+					"variables": {"input": "ctx"}
+				},
+				"questions": {
+					"questions": [{"text": "what is this?"}]
+				},
+				"expect": {
+					"questions": {
+						"contains": "Q=what is this?"
+					}
+				}
+			}
+		]
+	},
+	//
+	// Optional:
+	//		Local fields defintions - these define fields only for the
+	//		current service. You may specify them here, or directly
+	//		in the shape
+	//
+	"fields": {
+		"template": {
+			"type": "string",
+			"title": "Template",
+			"description": "Prompt template with {{variable}} placeholders, conditionals ({% if %}), and loops ({% for %})"
+		},
+		"variables": {
+			"type": "object",
+			"title": "Variables",
+			"description": "Key-value pairs of variables to substitute into the template"
+		}
+	},
+	//
+	// Required:
+	//		Defines the fields (shape) of the service. Either source or target
+	//		map be specified, or both, but at least one is required
+	//
+	"shape": [
+		{
+			"section": "Pipe",
+			"title": "Template",
+			"properties": [
+				"template",
+				"variables"
+			]
+		}
+	]
+}