fix(mcp-server): fix DuckDB connection info and Dockerfile caching (#1461)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: goldmedal

ibis-server/Dockerfile

@@ -46,11 +46,8 @@ RUN apt-get update && apt-get -y install libpq-dev && rm -rf /var/lib/apt/lists/
 
 ENV PYTHONUNBUFFERED=1 \
     PYTHONDONTWRITEBYTECODE=1 \
-    # pip
-    PIP_NO_CACHE_DIR=off \
     PIP_DISABLE_PIP_VERSION_CHECK=on \
     PIP_DEFAULT_TIMEOUT=100 \
-    # poetry
     POETRY_NO_INTERACTION=1 \
     POETRY_VIRTUALENVS_IN_PROJECT=1 \
     POETRY_VIRTUALENVS_CREATE=1
@@ -61,7 +58,9 @@ WORKDIR /app
 
 # Copy dependency files first so this layer is cached when only source changes
 COPY pyproject.toml poetry.lock ./
-RUN poetry install --without dev --with jupyter --no-root
+RUN --mount=type=cache,target=/root/.cache/pypoetry/cache \
+    --mount=type=cache,target=/root/.cache/pypoetry/artifacts \
+    poetry install --without dev --with jupyter --no-root
 
 # Install wheel (either from host or from wheel-docker stage)
 COPY --from=wheel-final /wheel/ /tmp/wheels/

mcp-server/app/templates/_fields.html

@@ -1,6 +1,9 @@
 {% set fields = datasource_fields.get(datasource, []) %}
 {% if fields %}
   {% for field in fields %}
+  {% if field.type == 'hidden' %}
+    <input type="hidden" name="{{ field.name }}" value="{{ field.get('value', '') }}">
+  {% else %}
   <label>
     {{ field.label }}
     <input
@@ -9,10 +12,14 @@
       placeholder="{{ field.placeholder }}"
       {% if field.type != 'password' %}value="{{ connection_info.get(field.name, '') }}"{% endif %}
     >
+    {% if field.get('hint') %}
+    <small style="color:var(--pico-muted-color)">{{ field.hint }}</small>
+    {% endif %}
     {% if is_docker and field.name == 'host' %}
     <small style="color:var(--pico-muted-color)">Running in Docker? Use <code>host.docker.internal</code> instead of <code>localhost</code>.</small>
     {% endif %}
   </label>
+  {% endif %}
   {% endfor %}
 {% elif datasource %}
   <label>

mcp-server/app/web.py

@@ -38,7 +38,8 @@
         {"name": "password", "label": "Password", "type": "password", "placeholder": ""},
     ],
     "DUCKDB": [
-        {"name": "path", "label": "File Path", "type": "text", "placeholder": "/path/to/db.duckdb"},
+        {"name": "url", "label": "Directory Path", "type": "text", "placeholder": "/data", "hint": "Path to a directory containing .duckdb files, not the .duckdb file itself."},
+        {"name": "format", "label": "Format", "type": "hidden", "value": "duckdb"},
     ],
     "BIGQUERY": [
         {"name": "project", "label": "Project ID", "type": "text", "placeholder": "my-gcp-project"},