Yaak Plugin: Prompt Select

Prompt Select is a Yaak template function plugin that interrupts request execution to display a dropdown UI prompt. It allows users to dynamically select and inject values at runtime without modifying the underlying request configuration.

Usage

Insert the prompt_select template tag into any valid Yaak request field (e.g., URL, Headers, Body).

Basic Syntax:

${prompt_select(label="Environment", title="Select environment", options="dev,staging,prod")}

Arguments

Argument	Required	Description
label	Yes	The input label displayed next to the dropdown dialog.
title	Yes	The title of the prompt dialog window.
options	Yes	A comma-separated list of the actual values to be injected. Supports nested template expressions.
labels	No	A comma-separated list of display names corresponding to the options. Defaults to the options values if omitted.
defaultValue	No	The option to pre-select when the prompt opens, or the fallback value if the user cancels the prompt.
store	No	Cache behavior for the selection. Accepts: none (default), forever, or expire.
namespace	No	Groups stored values to prevent key collisions across different requests. Supports nested template expressions.
key	No	A custom storage key. Defaults to label or title if omitted.
ttl	No	Time-to-live in seconds. Specifies how long to retain the cached selection (requires store="expire").

Core Behaviors

• Dynamic Template Evaluation: The options, labels, and namespace arguments are evaluated at runtime via Yaak’s template engine. You can nest other Yaak tags inside them (e.g., dynamically populating options using a JSONPath extraction from a previous response).
• Preview Mode Safety: When Yaak attempts to render previews (such as inside the CodeMirror editor or argument config view), the plugin safely skips template evaluation and dialog rendering. It immediately returns the defaultValue (or null) to prevent crashes from unresolvable context references.
• Label/Option Mapping: If the number of provided options and labels differs, the plugin safely maps them one-to-one up to the length of the shorter list.
• Storage Keys: Cached selections are stored strictly using the format namespace:key. If key is missing, it falls back to label, then title.

Examples

1. Basic Dropdown with Custom Labels

Displays human-readable labels in the UI while injecting the underlying technical value.

${[ prompt_select(label='Environment', title='Select Environment', options=b64'ZGV2LHN0YWdpbmcscHJvZA', labels=b64'RGV2ZWxvcG1lbnQsU3RhZ2luZyxQcm9kdWN0aW9u') ]}

2. Persistent Selection

Prompts the user once and caches the selection indefinitely. Useful for static tokens.

${[ prompt_select(label='Token', title='Select Auth Token', options=b64'dG9rZW4tYSx0b2tlbi1i', store='forever') ]}

3. Volatile Selection Caching (TTL)

Caches the user’s selection for 1 hour (3600 seconds) before expiring and prompting them again.

${[ prompt_select(label='Region', title='Select Target Region', options=b64'dXMtZWFzdC0xLGV1LXdlc3QtMQ', store='expire', ttl='3600') ]}

4. Dynamic Options via Nested Templates

Extracts options dynamically from a previous request using a nested Yaak tag. If the options evaluate to an empty list, it skips the prompt and returns the defaultValue.

${[ prompt_select(label='Gender', title='Select Gender', options=b64'TWFsZSwgRmVtYWxlLCBPdGhlcg', defaultValue=b64'JHtbIHJlc3BvbnNlLmJvZHkucGF0aChyZXF1ZXN0PSdycV81OENDUmNVb0VQJywgYmVoYXZpb3I9J3R0bCcsIHR0bD0nMjQwJywgcmVzdWx0PSdmaXJzdCcsIGpvaW49YjY0J0xDQScsIHBhdGg9YjY0J0pDNWtZWFJoTG5WelpYSXVaMlZ1WkdWeScpIF19', store='none', namespace=b64'JHtbY3R4LndvcmtzcGFjZSgpXX0', ttl='0') ]}