Add timeout function to limit processing time

docs/api-output.md

@@ -542,6 +542,26 @@ sharp('input.tiff')
 
 Returns **Sharp** 
 
+## timeout
+
+Set a timeout for processing, in seconds.
+Use a value of zero to continue processing indefinitely, the default behaviour.
+
+The clock starts when libvips opens an input image for processing.
+Time spent waiting for a libuv thread to become available is not included.
+
+### Parameters
+
+*   `options` **[Object][6]** 
+
+    *   `options.seconds` **[number][9]** Number of seconds after which processing will be stopped
+
+Returns **Sharp** 
+
+**Meta**
+
+*   **since**: 0.29.2
+
 [1]: #withmetadata
 
 [2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String

docs/changelog.md

@@ -6,6 +6,8 @@ Requires libvips v8.11.3
 
 ### v0.29.2 - TBD
 
+* Add `timeout` function to limit processing time.
+
 * Ensure `sharp.versions` is populated from vendored libvips.
 
 * Allow use of 'tif' to select TIFF output.

lib/constructor.js

@@ -273,6 +273,7 @@ const Sharp = function (input, options) {
     tileBackground: [255, 255, 255, 255],
     tileCentre: false,
     tileId: 'https://example.com/iiif',
+    timeoutSeconds: 0,
     linearA: 1,
     linearB: 0,
     // Function to notify of libvips warnings

lib/output.js

@@ -975,6 +975,31 @@ function tile (options) {
   return this._updateFormatOut('dz');
 }
 
+/**
+ * Set a timeout for processing, in seconds.
+ * Use a value of zero to continue processing indefinitely, the default behaviour.
+ *
+ * The clock starts when libvips opens an input image for processing.
+ * Time spent waiting for a libuv thread to become available is not included.
+ *
+ * @since 0.29.2
+ *
+ * @param {Object} options
+ * @param {number} options.seconds - Number of seconds after which processing will be stopped
+ * @returns {Sharp}
+ */
+function timeout (options) {
+  if (!is.plainObject(options)) {
+    throw is.invalidParameterError('options', 'object', options);
+  }
+  if (is.integer(options.seconds) && is.inRange(options.seconds, 0, 3600)) {
+    this.options.timeoutSeconds = options.seconds;
+  } else {
+    throw is.invalidParameterError('seconds', 'integer between 0 and 3600', options.seconds);
+  }
+  return this;
+}
+
 /**
  * Update the output format unless options.force is false,
  * in which case revert to input format.
@@ -1129,6 +1154,7 @@ module.exports = function (Sharp) {
     gif,
     raw,
     tile,
+    timeout,
     // Private
     _updateFormatOut,
     _setBooleanOption,

src/common.cc

@@ -610,6 +610,33 @@ namespace sharp {
     return warning;
   }
 
+  /*
+    Attach an event listener for progress updates, used to detect timeout
+  */
+  void SetTimeout(VImage image, int const seconds) {
+    if (seconds > 0) {
+      VipsImage *im = image.get_image();
+      if (im->progress_signal == NULL) {
+        int *timeout = VIPS_NEW(im, int);
+        *timeout = seconds;
+        g_signal_connect(im, "eval", G_CALLBACK(VipsProgressCallBack), timeout);
+        vips_image_set_progress(im, TRUE);
+      }
+    }
+  }
+
+  /*
+    Event listener for progress updates, used to detect timeout
+  */
+  void VipsProgressCallBack(VipsImage *im, VipsProgress *progress, int *timeout) {
+    // printf("VipsProgressCallBack progress=%d run=%d timeout=%d\n", progress->percent, progress->run, *timeout);
+    if (*timeout > 0 && progress->run >= *timeout) {
+      vips_image_set_kill(im, TRUE);
+      vips_error("timeout", "%d%% complete", progress->percent);
+      *timeout = 0;
+    }
+  }
+
   /*
     Calculate the (left, top) coordinates of the output image
     within the input image, applying the given gravity during an embed.

src/common.h

@@ -250,6 +250,16 @@ namespace sharp {
   */
   std::string VipsWarningPop();
 
+  /*
+    Attach an event listener for progress updates, used to detect timeout
+  */
+  void SetTimeout(VImage image, int const timeoutSeconds);
+
+  /*
+    Event listener for progress updates, used to detect timeout
+  */
+  void VipsProgressCallBack(VipsImage *image, VipsProgress *progress, int *timeoutSeconds);
+
   /*
     Calculate the (left, top) coordinates of the output image
     within the input image, applying the given gravity during an embed.

src/pipeline.cc

@@ -764,6 +764,7 @@ class PipelineWorker : public Napi::AsyncWorker {
         baton->loop);
 
       // Output
+      sharp::SetTimeout(image, baton->timeoutSeconds);
       if (baton->fileOut.empty()) {
         // Buffer output
         if (baton->formatOut == "jpeg" || (baton->formatOut == "input" && inputImageType == sharp::ImageType::JPEG)) {
@@ -1451,6 +1452,7 @@ Napi::Value pipeline(const Napi::CallbackInfo& info) {
     std::string k = sharp::AttrAsStr(mdStrKeys, i);
     baton->withMetadataStrs.insert(std::make_pair(k, sharp::AttrAsStr(mdStrs, k)));
   }
+  baton->timeoutSeconds = sharp::AttrAsUint32(options, "timeoutSeconds");
   // Format-specific
   baton->jpegQuality = sharp::AttrAsUint32(options, "jpegQuality");
   baton->jpegProgressive = sharp::AttrAsBool(options, "jpegProgressive");

src/pipeline.h

@@ -182,6 +182,7 @@ struct PipelineBaton {
   double withMetadataDensity;
   std::string withMetadataIcc;
   std::unordered_map<std::string, std::string> withMetadataStrs;
+  int timeoutSeconds;
   std::unique_ptr<double[]> convKernel;
   int convKernelWidth;
   int convKernelHeight;
@@ -315,6 +316,7 @@ struct PipelineBaton {
     withMetadata(false),
     withMetadataOrientation(-1),
     withMetadataDensity(0.0),
+    timeoutSeconds(0),
     convKernelWidth(0),
     convKernelHeight(0),
     convKernelScale(0.0),

test/unit/timeout.js

@@ -0,0 +1,26 @@
+'use strict';
+
+const assert = require('assert');
+
+const sharp = require('../../');
+const fixtures = require('../fixtures');
+
+describe('Timeout', function () {
+  it('Will timeout after 1s when performing slow blur operation', () => assert.rejects(
+    () => sharp(fixtures.inputJpg)
+      .blur(100)
+      .timeout({ seconds: 1 })
+      .toBuffer(),
+    /timeout: [0-9]+% complete/
+  ));
+
+  it('invalid object', () => assert.throws(
+    () => sharp().timeout('fail'),
+    /Expected object for options but received fail of type string/
+  ));
+
+  it('invalid seconds', () => assert.throws(
+    () => sharp().timeout({ seconds: 'fail' }),
+    /Expected integer between 0 and 3600 for seconds but received fail of type string/
+  ));
+});