# REST API - Request Unified REST request block for calling web APIs. Configure method, headers, query parameters and payload. Choose async (non-blocking) or sync (wait for response) runtime. Optionally extract a value from JSON response using a dotted/array path. ## đŸ“Ĩ Inputs `Enable` Optional boolean to run the request. When False the block can skip sending a request (default True). `Server Address` URL or endpoint to call (required). `Headers` Optional headers as a dictionary or JSON string. `Query Params` Optional query parameters as a dictionary or JSON string. `Payload` Optional request body (will be sent according to selected body mode). `Response Path` Optional text path used to extract a value from the JSON response (examples: data.items\[0].id or items\[2]). (here sockets are inputs) ## 📤 Outputs `OK` Boolean that is True when HTTP response indicates success. `Status Code` HTTP status code returned by the server. `Error` Error message for network/HTTP issues or parsing errors. `Response Text` Raw response body as text. `Response JSON` Parsed JSON object when available (otherwise None). `Response Headers` Map of response headers. `Elapsed (ms)` Request duration in milliseconds. `Extracted Data` Value resolved from `Response JSON` using `Response Path` (or None if not found). (here sockets are outputs) ## 🕹ī¸ Controls `Method` Choose HTTP method: GET / POST / PUT / PATCH / DELETE. `Body Mode` Choose how to send `Payload`: json / form / raw. `Runtime Mode` Choose execution mode: Async (non-blocking, keeps last result) or Sync (waits for response). `Timeout (s)` Timeout in seconds for requests (invalid values fall back to a safe default). `Verify SSL` Enable or disable TLS certificate verification (disable only for trusted test environments). ## ⚙ī¸ How it works * When `Enable` is true the block builds the request using the `Server Address`, `Headers`, `Query Params` and `Payload` along with chosen `Method` and `Body Mode`. * In `Sync` mode the block waits until the HTTP request completes and returns the fresh result on the same evaluation cycle. * In `Async` mode the block sends the request without blocking; the block keeps the last completed result and updates outputs once the background request finishes. * A JSON extraction path provided to `Response Path` resolves into `Extracted Data` if present; empty path yields no extraction. * On HTTP or network errors the block exposes an `Error` message and will mark the block result as invalid to help spotting failures. ## 📝 Usage 1. Set `Server Address` to your API endpoint. 2. Provide optional `Headers` and `Query Params` as dictionaries or JSON strings. 3. Put request body in `Payload` and choose `Body Mode` (use json for structured payloads). 4. Choose `Runtime Mode`: * Use `Async` to avoid blocking your scenario (good for UI/continuous pipelines). * Use `Sync` when you need the response immediately in the same run. 5. (Optional) Add a `Response Path` to extract a nested value from the JSON response for downstream logic. 6. Trigger the call by setting `Enable` to True or feeding a boolean trigger from other blocks. ## 💡 Tips and Tricks * Prepare JSON payloads with the `Data to JSON` block before feeding into `Payload` for cleaner structure and fewer formatting mistakes. * Use `Parse Data Dictionary` after `Response JSON` to safely access and route response fields if you prefer visual dictionary parsing. * Log responses or periodic results using `CSV Export` to keep a timestamped record of API responses for analysis. * For debugging flows, connect `Error` or `Response Text` to `Debug Input` to print or inspect unexpected outputs. * Combine with `Logic Input` or `Rising Edge` to control exactly when requests are sent (for example send only once per event). (here suggested blocks are from the provided list) ## 🛠ī¸ Troubleshooting * Server Address empty or invalid: ensure `Server Address` is a full URL (including protocol if required). * Request times out: increase `Timeout (s)` or ensure network connectivity to the server. * SSL verification errors in test environments: temporarily disable `Verify SSL` only if you trust the target. * Unexpected JSON parsing: check `Response Text` first; use a JSON-valid payload and set `Body Mode` to `json` when sending structured data. * No extracted data: verify the structure by inspecting `Response JSON` and adjust `Response Path` using dot/index notation (e.g. items\[0].id). ## 🔒 Privacy & Safety Be careful with sensitive data in `Headers` or `Payload` (API keys, passwords). When logging responses or exporting data, ensure sensitive fields are redacted. ## 🧭 Example workflows * Send sensor data periodically to a web service and record success/failure counts with `CSV Export`. * Post a structured JSON object created by `Data to JSON` and then feed `Extracted Data` into a decision flow (`Logic Input` / thresholds). * Use `Debug Input` to inspect server errors during development before switching to production logging. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.augelab.com/function-blocks/input-output/communication/rest-api-request.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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