fix(api): bound downloadFrom concurrency and entry count

The v8.30.0 image slimming replaced the libreoffice metapackage with an
explicit component list that omits libreoffice-math. Writer imports OMML
equations as Math objects, so without the component every formula is
silently dropped from converted PDFs.

Fixes #1644

.github/workflows/continuous-integration.yml

@@ -31,7 +31,7 @@ jobs:
       - name: Run linters
         uses: golangci/golangci-lint-action@v9
         with:
-          version: v2.12.2
+          version: v2.13.2
 
   lint-prettier:
     name: Lint non-Golang codebase

Makefile

@@ -38,6 +38,8 @@ API_DOWNLOAD_FROM_DENY_PRIVATE_IPS=false
 API_DOWNLOAD_FROM_DENY_PUBLIC_IPS=false
 API_DOWNLOAD_FROM_ENABLE_ENVIRONMENT_PROXY=false
 API_DOWNLOAD_FROM_MAX_RETRY=4
+API_DOWNLOAD_FROM_MAX_CONCURRENCY=10
+API_DOWNLOAD_FROM_MAX_ENTRIES=0
 API_DISABLE_DOWNLOAD_FROM=false
 API_DISABLE_HEALTH_CHECK_ROUTE_TELEMETRY=true
 API_DISABLE_ROOT_ROUTE_TELEMETRY=true

build/Dockerfile

@@ -1,7 +1,7 @@
 # ARG instructions do not create additional layers. Instead, next layers will
 # concatenate them. Also, we have to repeat ARG instructions in each build
 # stage that uses them.
-ARG GOLANG_VERSION=1.26.5
+ARG GOLANG_VERSION=1.27.0
 
 # ----------------------------------------------
 # pdfcpu binary build stage
@@ -88,7 +88,7 @@ RUN apt-get update -qq \
 
 WORKDIR /downloads
 
-RUN curl -Ls https://raw.githubusercontent.com/gotenberg/unoconverter/v0.4.0/unoconv -o unoconverter \
+RUN curl -Ls https://raw.githubusercontent.com/gotenberg/unoconverter/v0.5.0/unoconv -o unoconverter \
     && chmod +x unoconverter
 
 RUN curl -o pdftk-all.jar "https://gitlab.com/api/v4/projects/5024297/packages/generic/pdftk-java/$PDFTK_VERSION/pdftk-all.jar" \
@@ -259,7 +259,7 @@ RUN echo "deb http://deb.debian.org/debian trixie-backports main" >> /etc/apt/so
         hyphen-no hyphen-or hyphen-pa hyphen-pl hyphen-pt-br hyphen-pt-pt hyphen-ro hyphen-ru hyphen-sk hyphen-sl \
         hyphen-sr hyphen-sv hyphen-ta hyphen-te hyphen-th hyphen-uk hyphen-zu \
     && DEBIAN_FRONTEND=noninteractive apt-get install -y -qq --no-install-recommends -t trixie-backports \
-        libreoffice-writer libreoffice-calc libreoffice-impress libreoffice-draw python3-uno \
+        libreoffice-writer libreoffice-calc libreoffice-impress libreoffice-draw libreoffice-math python3-uno \
     # unoconverter will look for the Python binary, which has to be at version 3.
     && ln -s /usr/bin/python3 /usr/bin/python \
     # Cleanup.
@@ -386,7 +386,7 @@ RUN echo "deb http://deb.debian.org/debian trixie-backports main" >> /etc/apt/so
         hyphen-no hyphen-or hyphen-pa hyphen-pl hyphen-pt-br hyphen-pt-pt hyphen-ro hyphen-ru hyphen-sk hyphen-sl \
         hyphen-sr hyphen-sv hyphen-ta hyphen-te hyphen-th hyphen-uk hyphen-zu \
     && DEBIAN_FRONTEND=noninteractive apt-get install -y -qq --no-install-recommends -t trixie-backports \
-        libreoffice-writer libreoffice-calc libreoffice-impress libreoffice-draw python3-uno \
+        libreoffice-writer libreoffice-calc libreoffice-impress libreoffice-draw libreoffice-math python3-uno \
     # unoconverter will look for the Python binary, which has to be at version 3.
     && ln -s /usr/bin/python3 /usr/bin/python \
     # Cleanup.

compose.yaml

@@ -35,6 +35,8 @@ services:
       - "--api-download-from-deny-public-ips=${API_DOWNLOAD_FROM_DENY_PUBLIC_IPS}"
       - "--api-download-from-enable-environment-proxy=${API_DOWNLOAD_FROM_ENABLE_ENVIRONMENT_PROXY}"
       - "--api-download-from-max-retry=${API_DOWNLOAD_FROM_MAX_RETRY}"
+      - "--api-download-from-max-concurrency=${API_DOWNLOAD_FROM_MAX_CONCURRENCY}"
+      - "--api-download-from-max-entries=${API_DOWNLOAD_FROM_MAX_ENTRIES}"
       - "--api-disable-download-from=${API_DISABLE_DOWNLOAD_FROM}"
       - "--api-disable-health-check-route-telemetry=${API_DISABLE_HEALTH_CHECK_ROUTE_TELEMETRY}"
       - "--api-disable-root-route-telemetry=${API_DISABLE_ROOT_ROUTE_TELEMETRY}"

go.mod

@@ -1,11 +1,12 @@
 module github.com/gotenberg/gotenberg/v8
 
-go 1.26.5
+go 1.27.0
 
 require (
 	github.com/alexliesenfeld/health v0.8.1
 	github.com/chromedp/cdproto v0.0.0-20250803210736-d308e07a266d // pinned with chromedp v0.14.2, see below
 	github.com/chromedp/chromedp v0.14.2 // pinned: v0.15.x breaks the headless print-mode paint pipeline (rAF / ResizeObserver / IntersectionObserver stop firing, blank charts). See https://github.com/gotenberg/gotenberg/issues/1535.
+	github.com/coreos/go-oidc/v3 v3.20.0
 	github.com/cucumber/godog v0.16.0
 	github.com/dlclark/regexp2 v1.12.0
 	github.com/gomarkdown/markdown v0.0.0-20260725000948-8435af3f5984
@@ -20,10 +21,11 @@ require (
 	github.com/prometheus/client_golang v1.24.1
 	github.com/shirou/gopsutil/v4 v4.26.7
 	github.com/spf13/pflag v1.0.10
-	github.com/stretchr/testify v1.11.1
+	github.com/stretchr/testify v1.12.1
 	github.com/testcontainers/testcontainers-go v0.44.0
 	go.opentelemetry.io/contrib/bridges/otelslog v0.20.0
 	go.opentelemetry.io/contrib/exporters/autoexport v0.70.0
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.70.0
 	go.opentelemetry.io/otel v1.45.0
 	go.opentelemetry.io/otel/log v0.21.0
 	go.opentelemetry.io/otel/metric v1.45.0
@@ -37,11 +39,6 @@ require (
 	golang.org/x/text v0.41.0
 )
 
-require (
-	github.com/coreos/go-oidc/v3 v3.20.0
-	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.70.0
-)
-
 require (
 	dario.cat/mergo v1.0.2 // indirect
 	github.com/Azure/go-ansiterm v0.0.0-20250102033503-faa5f7b0171c // indirect
@@ -64,7 +61,6 @@ require (
 	github.com/cpuguy83/dockercfg v0.3.2 // indirect
 	github.com/cucumber/gherkin/go/v42 v42.0.1 // indirect
 	github.com/cucumber/messages/go/v34 v34.2.1 // indirect
-	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/distribution/reference v0.6.0 // indirect
 	github.com/docker/go-connections v0.8.1 // indirect
 	github.com/docker/go-units v0.5.0 // indirect
@@ -106,7 +102,6 @@ require (
 	github.com/opencontainers/go-digest v1.0.0 // indirect
 	github.com/opencontainers/image-spec v1.1.1 // indirect
 	github.com/pierrec/lz4/v4 v4.1.28 // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/power-devops/perfstat v0.0.0-20260805114148-88456608a4f6 // indirect
 	github.com/prometheus/client_model v0.6.2 // indirect
 	github.com/prometheus/common v0.70.1 // indirect
@@ -136,6 +131,7 @@ require (
 	go.opentelemetry.io/otel/exporters/stdout/stdoutmetric v1.45.0 // indirect
 	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.45.0 // indirect
 	go.opentelemetry.io/proto/otlp v1.11.0 // indirect
+	go.yaml.in/yaml/v3 v3.0.5 // indirect
 	go4.org v0.0.0-20260112195520-a5071408f32f // indirect
 	golang.org/x/crypto v0.55.0 // indirect
 	golang.org/x/oauth2 v0.36.0 // indirect
@@ -143,7 +139,6 @@ require (
 	golang.org/x/time v0.15.0 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20260810153831-ec0a7760b754 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20260810153831-ec0a7760b754 // indirect
-	google.golang.org/grpc v1.83.0 // indirect
+	google.golang.org/grpc v1.83.1 // indirect
 	google.golang.org/protobuf v1.36.12 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -55,7 +55,6 @@ github.com/cucumber/godog v0.16.0/go.mod h1:EDUX9yCqANK+GpbftMDeu61sUDtdLuo1JJgX
 github.com/cucumber/messages/go/v34 v34.2.1 h1:qBPEl+HhNJuRX8Kjaw1Pm60KOODZf2/4WQAi0SR/neE=
 github.com/cucumber/messages/go/v34 v34.2.1/go.mod h1:LYUPjqlTS1kS0pdkdf6sS5uirnjwiIzEGyXPezXNhL8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/distribution/reference v0.6.0 h1:0IXCQ5g4/QMHHkarYzh5l+u8T3t73zM5QvfrDyIgxBk=
 github.com/distribution/reference v0.6.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
@@ -130,10 +129,6 @@ github.com/klauspost/compress v1.19.2/go.mod h1:cwPg85FWrGar70rWktvGQj8/hthj3wpl
 github.com/klauspost/cpuid v1.2.0/go.mod h1:Pj4uuM528wm8OyEC2QMXAi2YiTZ96dNQPGgoMS4s3ek=
 github.com/klauspost/pgzip v1.2.6 h1:8RXeL5crjEUFnR2/Sn6GJNWtSQ3Dk8pq4CL3jvdDyjU=
 github.com/klauspost/pgzip v1.2.6/go.mod h1:Ch1tH69qFZu15pkjo5kYi6mth2Zzwzt50oCQKQE9RUs=
-github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
-github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
-github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
-github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/labstack/echo/v4 v4.15.4 h1:DL45vVYa+BWE+XuW+zZNd9H0YEdZ80UAWJGcTVW4EVs=
@@ -192,7 +187,6 @@ github.com/orisano/pixelmatch v0.0.0-20220722002657-fb0b55479cde h1:x0TT0RDC7UhA
 github.com/orisano/pixelmatch v0.0.0-20220722002657-fb0b55479cde/go.mod h1:nZgzbfBr3hhjoZnS66nKrHmduYNpc34ny7RK4z5/HM0=
 github.com/pierrec/lz4/v4 v4.1.28 h1:pPEPwRJ4kybBTfGt28q7lQsRJQHhC08axprdLD5Ppio=
 github.com/pierrec/lz4/v4 v4.1.28/go.mod h1:EoQMVJgeeEOMsCqCzqFm2O0cJvljX2nGZjcRIPL34O4=
-github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/power-devops/perfstat v0.0.0-20260805114148-88456608a4f6 h1:jL3a8soXdzuTCcRnKhOmtcsVOObdDTFf4O2B403HPRU=
 github.com/power-devops/perfstat v0.0.0-20260805114148-88456608a4f6/go.mod h1:OmDBASR4679mdNQnz2pUhc2G8CO2JrUAVFDRBDP/hJE=
@@ -206,8 +200,6 @@ github.com/prometheus/otlptranslator v1.0.0 h1:s0LJW/iN9dkIH+EnhiD3BlkkP5QVIUVEo
 github.com/prometheus/otlptranslator v1.0.0/go.mod h1:vRYWnXvI6aWGpsdY/mOT/cbeVRBlPWtBNDb7kGR3uKM=
 github.com/prometheus/procfs v0.21.1 h1:GljZCt+zSTS+NZq88cyQ1LjZ+RCHp3uVuabBWA5+OJI=
 github.com/prometheus/procfs v0.21.1/go.mod h1:aB55Cww9pdSJVHk0hUf0inxWyyjPogFIjmHKYgMKmtY=
-github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
-github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
 github.com/shirou/gopsutil/v4 v4.26.7 h1:IXzpHz/dkMRYAhKkOXr1HB6SuzWU3eoyyeWe7g3bNZc=
 github.com/shirou/gopsutil/v4 v4.26.7/go.mod h1:5O9FjBiXoTDFatIWjZZosqj4pV0DRtLx598xGbBehzM=
 github.com/sirupsen/logrus v1.10.0 h1:T8MxJJXVZkfcC5zSRMRAg2F8+lxjmUCGGWPzFxO+Msc=
@@ -228,8 +220,8 @@ github.com/stretchr/objx v0.5.3/go.mod h1:rDQraq+vQZU7Fde9LOZLr8Tax6zZvy4kuNKF+Q
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
-github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.12.1 h1:EuwCh5fleGS7H32xRwO3wRGT7DxrDhLAT6FF8MpWDWE=
-github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+github.com/stretchr/testify v1.12.1/go.mod h1:MDEgiDPPsNp5cuIrHPPCyornHKgEVbtFUmoNlxoYthg=
 github.com/testcontainers/testcontainers-go v0.44.0 h1:/Fwh6HY1mIikhnm9e7HwoxGycx0lzRAE0f5VQpjFxzI=
 github.com/testcontainers/testcontainers-go v0.44.0/go.mod h1:IcnwQrYTO86xHXu5bvMaBH7ATlbS3Qn1M1QWW3c66rE=
 github.com/tklauser/go-sysconf v0.4.0 h1:7H0uAN+7RkwWRaxhYXDLqa5V3LPrJeV8wmD9dRUgPQU=
@@ -303,6 +295,8 @@ go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 go.yaml.in/yaml/v2 v2.4.4 h1:tuyd0P+2Ont/d6e2rl3be67goVK4R6deVxCUX5vyPaQ=
 go.yaml.in/yaml/v2 v2.4.4/go.mod h1:gMZqIpDtDqOfM0uNfy0SkpRhvUryYH0Z6wdMYcacYXQ=
+go.yaml.in/yaml/v3 v3.0.5 h1:N6y/pJk8buWs9NY5ERU2HSMfm+IuD/OtfdAnq6kESPw=
+go.yaml.in/yaml/v3 v3.0.5/go.mod h1:HVTZu1O7/Vkt2N+BFy8Zza+lnLsABggaTM2ZpNIGuKg=
 go4.org v0.0.0-20260112195520-a5071408f32f h1:ziUVAjmTPwQMBmYR1tbdRFJPtTcQUI12fH9QQjfb0Sw=
 go4.org v0.0.0-20260112195520-a5071408f32f/go.mod h1:ZRJnO5ZI4zAwMFp+dS1+V6J6MSyAowhRqAE+DPa1Xp0=
 golang.org/x/crypto v0.55.0 h1:+KWHjbgOaAQ66dh/YlkZKHlz9ZUlq61AFirAR9ntP8M=
@@ -333,15 +327,12 @@ google.golang.org/genproto/googleapis/api v0.0.0-20260810153831-ec0a7760b754 h1:
 google.golang.org/genproto/googleapis/api v0.0.0-20260810153831-ec0a7760b754/go.mod h1:q/3oV3jAi5vwelxsVAprMBC8BcM2zmNe+IjRGd+9/ks=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20260810153831-ec0a7760b754 h1:k5CJw9e5ONCcA/u0webKt092npXuY+KeGh3Q8NAVf0g=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20260810153831-ec0a7760b754/go.mod h1:4Hqkh8ycfw05ld/3BWL7rJOSfebL2Q+DVDeRgYgxUU8=
-google.golang.org/grpc v1.83.0 h1:JeNZEKJFbQxArAMl+hiytHauacDNqJUllNfmIMmpqnQ=
+google.golang.org/grpc v1.83.1 h1:HIO0+BEtBP6soyqvqC8sNUjZ7bTs+0hFQuFF+RAy++Y=
-google.golang.org/grpc v1.83.0/go.mod h1:kDyl6SKsiHKt0uylY5gtn5cEjkrIOhQOGDgIc4JGwzQ=
+google.golang.org/grpc v1.83.1/go.mod h1:kDyl6SKsiHKt0uylY5gtn5cEjkrIOhQOGDgIc4JGwzQ=
 google.golang.org/protobuf v1.36.12 h1:pJOKDDOyeXErUroCihFAd5LQuwXBSpVnKGrj5o/fwxc=
 google.golang.org/protobuf v1.36.12/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
-gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools/v3 v3.5.2 h1:7koQfIKdy+I8UTetycgUqXWSDwpgv193Ka+qRsmBY8Q=
 gotest.tools/v3 v3.5.2/go.mod h1:LtdLGcnqToBH83WByAAi/wiwSFCArdFIUV/xxN4pcjA=

pkg/gotenberg/internal/otel/otel.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log/slog"
 	"os"
+	"strings"
 	"sync/atomic"
 
 	"go.opentelemetry.io/contrib/bridges/otelslog"
@@ -74,6 +75,24 @@ func buildResource(ctx context.Context, logger *slog.Logger, serviceName, servic
 	return merged
 }
 
+// OTEL_*_EXPORTER select the exporter for each signal. autoexport treats an
+// unset or empty value as a request for the OTLP exporter, which then fails
+// against the default localhost:4318 endpoint when nothing listens there and,
+// for metrics, keeps retrying on the periodic reader's timer. Gotenberg keeps
+// telemetry opt-in: a signal with no exporter configured is built without one
+// and stays inert. See https://github.com/gotenberg/gotenberg/issues/1643.
+const (
+	tracesExporterEnvKey  = "OTEL_TRACES_EXPORTER"
+	metricsExporterEnvKey = "OTEL_METRICS_EXPORTER"
+	logsExporterEnvKey    = "OTEL_LOGS_EXPORTER"
+)
+
+// exporterConfigured reports whether the operator selected an exporter for the
+// signal owning envKey. An unset or blank value keeps that signal off.
+func exporterConfigured(envKey string) bool {
+	return strings.TrimSpace(os.Getenv(envKey)) != ""
+}
+
 // InitTracerProvider initializes the OpenTelemetry tracer provider.
 func InitTracerProvider(logger *slog.Logger, serviceName, serviceVersion string) (shutdown func(context.Context) error, err error) {
 	initOtelLogger(logger)
@@ -86,13 +105,14 @@ func InitTracerProvider(logger *slog.Logger, serviceName, serviceVersion string)
 		trace.WithResource(res),
 	}
 
-	traceExporter, err := autoexport.NewSpanExporter(ctx)
+	if exporterConfigured(tracesExporterEnvKey) {
-	if err != nil {
+		traceExporter, err := autoexport.NewSpanExporter(ctx)
-		return nil, err
+		if err != nil {
-	}
+			return nil, err
-
+		}
-	if !autoexport.IsNoneSpanExporter(traceExporter) {
+		if !autoexport.IsNoneSpanExporter(traceExporter) {
-		traceOpts = append(traceOpts, trace.WithBatcher(traceExporter))
+			traceOpts = append(traceOpts, trace.WithBatcher(traceExporter))
+		}
 	}
 
 	traceProvider := trace.NewTracerProvider(traceOpts...)
@@ -119,13 +139,14 @@ func InitMeterProvider(logger *slog.Logger, serviceName, serviceVersion string)
 	}
 	metricOpts = append(metricOpts, exemplarFilterOptions()...)
 
-	metricReader, err := autoexport.NewMetricReader(ctx)
+	if exporterConfigured(metricsExporterEnvKey) {
-	if err != nil {
+		metricReader, err := autoexport.NewMetricReader(ctx)
-		return nil, err
+		if err != nil {
-	}
+			return nil, err
-
+		}
-	if !autoexport.IsNoneMetricReader(metricReader) {
+		if !autoexport.IsNoneMetricReader(metricReader) {
-		metricOpts = append(metricOpts, metric.WithReader(metricReader))
+			metricOpts = append(metricOpts, metric.WithReader(metricReader))
+		}
 	}
 
 	meterProvider := metric.NewMeterProvider(metricOpts...)
@@ -157,13 +178,14 @@ func InitLoggerProvider(logger *slog.Logger, serviceName, serviceVersion string)
 		log.WithResource(res),
 	}
 
-	logExporter, err := autoexport.NewLogExporter(ctx)
+	if exporterConfigured(logsExporterEnvKey) {
-	if err != nil {
+		logExporter, err := autoexport.NewLogExporter(ctx)
-		return nil, nil, err
+		if err != nil {
-	}
+			return nil, nil, err
-
+		}
-	if !autoexport.IsNoneLogExporter(logExporter) {
+		if !autoexport.IsNoneLogExporter(logExporter) {
-		logOpts = append(logOpts, log.WithProcessor(log.NewBatchProcessor(logExporter)))
+			logOpts = append(logOpts, log.WithProcessor(log.NewBatchProcessor(logExporter)))
+		}
 	}
 
 	loggerProvider := log.NewLoggerProvider(logOpts...)

pkg/gotenberg/internal/otel/otel_test.go

@@ -89,6 +89,49 @@ func TestInitTracerProvider_HonorsSamplerEnv(t *testing.T) {
 	}
 }
 
+// TestExporterConfigured pins the opt-in gate: an unset or blank
+// OTEL_*_EXPORTER keeps the signal off, so Gotenberg never wires the OTLP
+// exporter that autoexport would otherwise default to and fail to reach at
+// localhost:4318. See https://github.com/gotenberg/gotenberg/issues/1643.
+func TestExporterConfigured(t *testing.T) {
+	const key = "OTEL_METRICS_EXPORTER"
+
+	orig, had := os.LookupEnv(key)
+	t.Cleanup(func() {
+		if had {
+			os.Setenv(key, orig)
+			return
+		}
+		os.Unsetenv(key)
+	})
+
+	for _, tc := range []struct {
+		scenario string
+		unset    bool
+		value    string
+		want     bool
+	}{
+		{"unset", true, "", false},
+		{"empty", false, "", false},
+		{"whitespace only", false, "   ", false},
+		{"none", false, "none", true},
+		{"otlp", false, "otlp", true},
+		{"padded value", false, "  otlp  ", true},
+	} {
+		t.Run(tc.scenario, func(t *testing.T) {
+			if tc.unset {
+				os.Unsetenv(key)
+			} else {
+				os.Setenv(key, tc.value)
+			}
+
+			if got := exporterConfigured(key); got != tc.want {
+				t.Errorf("exporterConfigured(%q) = %v, want %v", key, got, tc.want)
+			}
+		})
+	}
+}
+
 func TestExemplarFilterOptions(t *testing.T) {
 	t.Run("default pins trace-based", func(t *testing.T) {
 		if v, ok := os.LookupEnv("OTEL_METRICS_EXEMPLAR_FILTER"); ok {

pkg/modules/api/api.go

@@ -67,6 +67,8 @@ type downloadFromConfig struct {
 	denyPublicIPs          bool
 	enableEnvironmentProxy bool
 	maxRetry               int
+	maxConcurrency         int
+	maxEntries             int
 	disable                bool
 }
 
@@ -212,6 +214,8 @@ func (a *Api) Descriptor() gotenberg.ModuleDescriptor {
 			fs.Bool("api-download-from-deny-public-ips", false, "Reject downloadFrom URLs whose host resolves to a public IP address. Enable on air-gapped or data-governed deployments to prevent downloads from reaching the public internet")
 			fs.Bool("api-download-from-enable-environment-proxy", false, "Route downloadFrom fetches through the proxy defined by the standard HTTP_PROXY, HTTPS_PROXY, and NO_PROXY variables, including credentials")
 			fs.Int("api-download-from-max-retry", 4, "Set the maximum number of retries for the download from feature")
+			fs.Int("api-download-from-max-concurrency", 10, "Set the maximum number of downloadFrom entries fetched concurrently per request - bounds the outbound fan-out. Set to 0 to disable this feature")
+			fs.Int("api-download-from-max-entries", 0, "Set the maximum number of downloadFrom entries allowed per request. Set to 0 to disable this feature")
 			fs.Bool("api-disable-download-from", false, "Disable the download from feature")
 			fs.Bool("api-disable-health-check-route-telemetry", true, "Disable telemetry for health check route")
 			fs.Bool("api-disable-root-route-telemetry", true, "Disable telemetry for the root route")
@@ -255,6 +259,8 @@ func (a *Api) Provision(ctx *gotenberg.Context) error {
 		denyPublicIPs:          flags.MustBool("api-download-from-deny-public-ips"),
 		enableEnvironmentProxy: flags.MustBool("api-download-from-enable-environment-proxy"),
 		maxRetry:               flags.MustInt("api-download-from-max-retry"),
+		maxConcurrency:         flags.MustInt("api-download-from-max-concurrency"),
+		maxEntries:             flags.MustInt("api-download-from-max-entries"),
 		disable:                flags.MustBool("api-disable-download-from"),
 	}
 	a.disableHealthCheckRouteTelemetry = flags.MustDeprecatedBool("api-disable-health-check-logging", "api-disable-health-check-route-telemetry")
@@ -404,6 +410,18 @@ func (a *Api) Validate() error {
 		}
 	}
 
+	if a.downloadFromCfg.maxConcurrency < 0 {
+		err = errors.Join(err,
+			fmt.Errorf("download from max concurrency must not be negative, got %d; set --api-download-from-max-concurrency (env API_DOWNLOAD_FROM_MAX_CONCURRENCY) to 0 to disable the limit", a.downloadFromCfg.maxConcurrency),
+		)
+	}
+
+	if a.downloadFromCfg.maxEntries < 0 {
+		err = errors.Join(err,
+			fmt.Errorf("download from max entries must not be negative, got %d; set --api-download-from-max-entries (env API_DOWNLOAD_FROM_MAX_ENTRIES) to 0 to disable the limit", a.downloadFromCfg.maxEntries),
+		)
+	}
+
 	if (a.tlsCertFile != "" && a.tlsKeyFile == "") || (a.tlsCertFile == "" && a.tlsKeyFile != "") {
 		err = errors.Join(err,
 			errors.New("both TLS certificate and key files must be set"),

pkg/modules/api/context.go

@@ -222,6 +222,16 @@ func newContext(echoCtx echo.Context, logger *slog.Logger, fs *gotenberg.FileSys
 			)
 		}
 
+		// Reject oversized arrays at the trust boundary, before allocating
+		// the results slice or spawning any goroutine, so a compact request
+		// cannot inflate into an unbounded fan-out.
+		if downloadFromCfg.maxEntries > 0 && len(dls) > downloadFromCfg.maxEntries {
+			return nil, cancel, WrapError(
+				fmt.Errorf("too many downloadFrom entries: got %d, max %d", len(dls), downloadFromCfg.maxEntries),
+				NewSentinelHttpError(http.StatusBadRequest, fmt.Sprintf("Invalid 'downloadFrom' form field value: too many entries, the maximum is %d", downloadFromCfg.maxEntries)),
+			)
+		}
+
 		// Each goroutine writes to its own results slot. The main
 		// goroutine merges into ctx.files, ctx.diskToOriginal, and
 		// ctx.filesByField after eg.Wait() to avoid concurrent map
@@ -232,6 +242,13 @@ func newContext(echoCtx echo.Context, logger *slog.Logger, fs *gotenberg.FileSys
 		results := make([]downloadFromResult, len(dls))
 
 		eg, _ := errgroup.WithContext(ctx)
+		// Bound the number of in-flight downloads. Each entry allocates a
+		// retryable client, an outbound transport, a span, and logger state,
+		// so an unbounded array would otherwise exhaust process memory. A
+		// value of 0 keeps the fan-out unbounded.
+		if downloadFromCfg.maxConcurrency > 0 {
+			eg.SetLimit(downloadFromCfg.maxConcurrency)
+		}
 		for i, dl := range dls {
 			eg.Go(func() error {
 				deadline, ok := ctx.Deadline()

pkg/modules/api/context_test.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log/slog"
 	"mime/multipart"
@@ -11,6 +12,7 @@ import (
 	"net/http/httptest"
 	"os"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -209,6 +211,137 @@ func TestNewContext_DownloadFromConcurrentMapWrites(t *testing.T) {
 	}
 }
 
+// An oversized downloadFrom array must be rejected at the trust boundary with
+// a 400, before any download goroutine is spawned.
+// https://github.com/gotenberg/gotenberg/security/advisories/GHSA-6vqw-2jgm-4x88
+func TestNewContext_DownloadFromMaxEntries(t *testing.T) {
+	var hits atomic.Int64
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		hits.Add(1)
+		w.Header().Set("Content-Disposition", `attachment; filename="download.txt"`)
+		_, _ = w.Write([]byte("downloaded"))
+	}))
+	defer server.Close()
+
+	dls := make([]downloadFrom, 3)
+	for i := range dls {
+		dls[i] = downloadFrom{Url: fmt.Sprintf("%s/file?i=%d", server.URL, i)}
+	}
+
+	payload, err := json.Marshal(dls)
+	if err != nil {
+		t.Fatalf("marshal downloadFrom payload: %v", err)
+	}
+
+	body := new(bytes.Buffer)
+	writer := multipart.NewWriter(body)
+	err = writer.WriteField("downloadFrom", string(payload))
+	if err != nil {
+		t.Fatalf("write downloadFrom field: %v", err)
+	}
+	err = writer.Close()
+	if err != nil {
+		t.Fatalf("close multipart writer: %v", err)
+	}
+
+	req := httptest.NewRequest(http.MethodPost, "/forms/libreoffice/convert", body)
+	req.Header.Set("Content-Type", writer.FormDataContentType())
+
+	echoCtx := echo.New().NewContext(req, httptest.NewRecorder())
+	logger := slog.New(slog.DiscardHandler)
+	fs := gotenberg.NewFileSystem(new(gotenberg.OsMkdirAll))
+	downloadFromCfg := downloadFromConfig{maxEntries: 2}
+
+	_, cancel, err := newContext(echoCtx, logger, fs, 10*time.Second, 0, downloadFromCfg)
+	if cancel != nil {
+		defer cancel()
+	}
+	if err == nil {
+		t.Fatal("newContext returned no error, want a 400 for too many entries")
+	}
+
+	var httpErr HttpError
+	if !errors.As(err, &httpErr) {
+		t.Fatalf("error %v is not an HttpError", err)
+	}
+	if status, _ := httpErr.HttpError(); status != http.StatusBadRequest {
+		t.Fatalf("HTTP status = %d, want %d", status, http.StatusBadRequest)
+	}
+	if got := hits.Load(); got != 0 {
+		t.Fatalf("server hits = %d, want 0 (rejected before any download)", got)
+	}
+}
+
+// The number of in-flight downloadFrom fetches must never exceed the
+// configured concurrency limit, regardless of array length.
+// https://github.com/gotenberg/gotenberg/security/advisories/GHSA-6vqw-2jgm-4x88
+func TestNewContext_DownloadFromMaxConcurrency(t *testing.T) {
+	const (
+		downloads      = 8
+		maxConcurrency = 2
+	)
+
+	var current, peak atomic.Int64
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		inFlight := current.Add(1)
+		for {
+			observed := peak.Load()
+			if inFlight <= observed || peak.CompareAndSwap(observed, inFlight) {
+				break
+			}
+		}
+		time.Sleep(20 * time.Millisecond)
+		current.Add(-1)
+
+		filename := fmt.Sprintf("download-%s.txt", r.URL.Query().Get("i"))
+		w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filename))
+		_, _ = w.Write([]byte("downloaded"))
+	}))
+	defer server.Close()
+
+	dls := make([]downloadFrom, downloads)
+	for i := range dls {
+		dls[i] = downloadFrom{Url: fmt.Sprintf("%s/file?i=%d", server.URL, i)}
+	}
+
+	payload, err := json.Marshal(dls)
+	if err != nil {
+		t.Fatalf("marshal downloadFrom payload: %v", err)
+	}
+
+	body := new(bytes.Buffer)
+	writer := multipart.NewWriter(body)
+	err = writer.WriteField("downloadFrom", string(payload))
+	if err != nil {
+		t.Fatalf("write downloadFrom field: %v", err)
+	}
+	err = writer.Close()
+	if err != nil {
+		t.Fatalf("close multipart writer: %v", err)
+	}
+
+	req := httptest.NewRequest(http.MethodPost, "/forms/libreoffice/convert", body)
+	req.Header.Set("Content-Type", writer.FormDataContentType())
+
+	echoCtx := echo.New().NewContext(req, httptest.NewRecorder())
+	logger := slog.New(slog.DiscardHandler)
+	fs := gotenberg.NewFileSystem(new(gotenberg.OsMkdirAll))
+	downloadFromCfg := downloadFromConfig{maxConcurrency: maxConcurrency}
+
+	ctx, cancel, err := newContext(echoCtx, logger, fs, 10*time.Second, 0, downloadFromCfg)
+	if err != nil {
+		t.Fatalf("newContext returned error: %v", err)
+	}
+	defer cancel()
+
+	if got := len(ctx.files); got != downloads {
+		t.Fatalf("downloaded files = %d, want %d", got, downloads)
+	}
+	if got := peak.Load(); got > maxConcurrency {
+		t.Fatalf("peak concurrency = %d, want <= %d", got, maxConcurrency)
+	}
+}
+
 func TestSanitizeFilename(t *testing.T) {
 	for _, tc := range []struct {
 		scenario string

pkg/modules/api/formdata.go

@@ -612,7 +612,7 @@ func (form *FormData) mustValue(key string, target any, defaultValue any) *FormD
 	val, ok := form.values[key]
 
 	if !ok || val[0] == "" {
-		switch t := (target).(type) {
+		switch t := target.(type) {
 		case *string:
 			*t = defaultValue.(string)
 		case *bool:
@@ -659,7 +659,7 @@ func (form *FormData) mustMandatoryField(key string, target any) *FormData {
 func (form *FormData) mustAssign(key, value string, target any) *FormData {
 	var err error
 
-	switch t := (target).(type) {
+	switch t := target.(type) {
 	case *string:
 		*t = value
 	case *bool:

pkg/modules/chromium/browser.go

@@ -523,8 +523,45 @@ func (b *chromiumBrowser) do(ctx context.Context, logger *slog.Logger, url strin
 		cancelOnMainPageError:   taskCancel,
 	})
 
+	var (
+		crashed   error
+		crashedMu sync.RWMutex
+	)
+
+	// See https://github.com/gotenberg/gotenberg/issues/1640.
+	listenForEventTargetCrashed(taskCtx, logger, eventTargetCrashedOptions{
+		crashed:   &crashed,
+		crashedMu: &crashedMu,
+		cancel:    taskCancel,
+	})
+
 	runErr := chromedp.Run(taskCtx, tasks...)
 
+	// A crashed renderer is the root cause of every other failure this
+	// conversion may have recorded, so check it first.
+	// See https://github.com/gotenberg/gotenberg/issues/1640.
+	crashedMu.RLock()
+	defer crashedMu.RUnlock()
+
+	if crashed != nil {
+		return fmt.Errorf("handle tasks: %w", crashed)
+	}
+
+	// The browser context is only ever canceled when the browser process
+	// dies or is stopped, never on a request timeout. If the run failed
+	// and the browser context is done, the conversion failed because the
+	// browser went away mid-flight; fail fast with the same crash error
+	// instead of letting the error fall through as a generic context
+	// cancellation. The check is gated on runErr so a successful
+	// conversion is never discarded by a browser death that lands right
+	// after it.
+	// See https://github.com/gotenberg/gotenberg/issues/1640.
+	if runErr != nil {
+		if err := b.ctx.Err(); err != nil {
+			return fmt.Errorf("handle tasks: %w", ErrChromiumCrashed)
+		}
+	}
+
 	// Check event-driven errors first — they take priority over chromedp.Run
 	// errors because they carry the actual root cause (e.g., HTTP 500 from
 	// the main page). When we cancel taskCtx on a main page error,

pkg/modules/chromium/chromium.go

@@ -71,6 +71,10 @@ var (
 	// ErrResourceLoadingFailed happens when one or more resources failed to load.
 	ErrResourceLoadingFailed = errors.New("resource loading failed")
 
+	// ErrChromiumCrashed happens when the Chromium renderer crashes during a
+	// conversion.
+	ErrChromiumCrashed = errors.New("chromium crashed")
+
 	// PDF specific.
 
 	// ErrOmitBackgroundWithoutPrintBackground happens if
@@ -1106,6 +1110,8 @@ func chromiumErrorType(err error, queueReason string) string {
 		errors.Is(err, ErrInvalidEvaluationExpression),
 		errors.Is(err, ErrInvalidSelectorQuery):
 		return gotenberg.ErrorTypeInvalidInput
+	case errors.Is(err, ErrChromiumCrashed):
+		return "chromium_unavailable"
 	case errors.Is(err, gotenberg.ErrMaximumQueueSizeExceeded):
 		return queueReason
 	case errors.Is(err, gotenberg.ErrProcessAlreadyRestarting):

pkg/modules/chromium/errortype_test.go

@@ -21,6 +21,7 @@ func TestChromiumErrorType(t *testing.T) {
 		{"invalid resource http status", ErrInvalidResourceHttpStatusCode, "chromium_unavailable", "invalid_input"},
 		{"loading failed", ErrLoadingFailed, "chromium_unavailable", "invalid_input"},
 		{"resource loading failed", ErrResourceLoadingFailed, "chromium_unavailable", "invalid_input"},
+		{"crashed", ErrChromiumCrashed, "chromium_unavailable", "chromium_unavailable"},
 		{"invalid evaluation expression", ErrInvalidEvaluationExpression, "chromium_unavailable", "invalid_input"},
 		{"invalid selector query", ErrInvalidSelectorQuery, "chromium_unavailable", "invalid_input"},
 		{"pdf queue", gotenberg.ErrMaximumQueueSizeExceeded, "chromium_unavailable", "chromium_unavailable"},

pkg/modules/chromium/events.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/chromedp/cdproto/cdp"
 	"github.com/chromedp/cdproto/fetch"
+	"github.com/chromedp/cdproto/inspector"
 	"github.com/chromedp/cdproto/network"
 	"github.com/chromedp/cdproto/page"
 	"github.com/chromedp/cdproto/runtime"
@@ -521,6 +522,38 @@ func listenForEventExceptionThrown(ctx context.Context, logger *slog.Logger, con
 	})
 }
 
+type eventTargetCrashedOptions struct {
+	crashed   *error
+	crashedMu *sync.RWMutex
+	cancel    context.CancelFunc
+}
+
+// listenForEventTargetCrashed listens for the Inspector.targetCrashed event,
+// which Chromium sends when the renderer serving the conversion's tab
+// crashes. chromedp enables the Inspector domain on every target but does
+// not handle this event: left alone, the in-flight CDP command never
+// receives a response and the conversion blocks until the request deadline.
+// Record the crash and cancel the task context so the conversion fails fast
+// instead.
+// See https://github.com/gotenberg/gotenberg/issues/1640.
+func listenForEventTargetCrashed(ctx context.Context, logger *slog.Logger, options eventTargetCrashedOptions) {
+	chromedp.ListenTarget(ctx, func(ev any) {
+		if _, ok := ev.(*inspector.EventTargetCrashed); ok {
+			logger.DebugContext(ctx, "event EventTargetCrashed fired")
+
+			options.crashedMu.Lock()
+			defer options.crashedMu.Unlock()
+
+			*options.crashed = ErrChromiumCrashed
+
+			// Cancel the task context so the in-flight CDP command aborts
+			// immediately instead of waiting for a response the crashed
+			// renderer can never send.
+			options.cancel()
+		}
+	})
+}
+
 // waitForEventDomContentEventFired registers a listener for the
 // DomContentEventFired event and returns a waiter that blocks until the
 // event fires or ctx is done. The listener registers at call time, not

pkg/modules/chromium/routes.go

@@ -1020,6 +1020,16 @@ func handleChromiumError(err error, options Options) error {
 		return nil
 	}
 
+	if errors.Is(err, ErrChromiumCrashed) {
+		return api.WrapError(
+			err,
+			api.NewSentinelHttpError(
+				http.StatusServiceUnavailable,
+				"Chromium crashed while processing the request. Retry, or reduce the workload if the problem persists.",
+			),
+		)
+	}
+
 	if errors.Is(err, ErrInvalidEvaluationExpression) {
 		if options.WaitForExpression == "" {
 			// We do not expect the 'waitWindowStatus' form field to return

pkg/modules/chromium/routes_test.go

@@ -0,0 +1,51 @@
+package chromium
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+
+	"github.com/gotenberg/gotenberg/v8/pkg/modules/api"
+)
+
+// TestHandleChromiumError_Crashed pins the mapping of a Chromium renderer
+// crash to a 503 Service Unavailable. When the renderer crashes mid-conversion,
+// the request must fail fast with 503 rather than hang until the deadline and
+// surface as a generic timeout.
+// See https://github.com/gotenberg/gotenberg/issues/1640.
+func TestHandleChromiumError_Crashed(t *testing.T) {
+	// Mirror the wrapping done by [chromiumBrowser.do].
+	err := handleChromiumError(fmt.Errorf("handle tasks: %w", ErrChromiumCrashed), Options{})
+	if err == nil {
+		t.Fatal("expected an error, got none")
+	}
+
+	status, message := api.ParseError(err)
+	if status != http.StatusServiceUnavailable {
+		t.Errorf("status = %d, want %d (message: %s)", status, http.StatusServiceUnavailable, message)
+	}
+
+	want := "Chromium crashed while processing the request. Retry, or reduce the workload if the problem persists."
+	if message != want {
+		t.Errorf("message = %q, want %q", message, want)
+	}
+}
+
+// TestHandleChromiumError_CrashedTakesPrecedence guards the ordering in
+// [handleChromiumError]: a crash is a server-side failure and must map to 503
+// even when the error chain also carries a marker that another branch would
+// map to a client-error status.
+func TestHandleChromiumError_CrashedTakesPrecedence(t *testing.T) {
+	err := handleChromiumError(
+		fmt.Errorf("handle tasks: %w; %w", ErrChromiumCrashed, ErrInvalidHttpStatusCode),
+		Options{},
+	)
+	if err == nil {
+		t.Fatal("expected an error, got none")
+	}
+
+	status, _ := api.ParseError(err)
+	if status != http.StatusServiceUnavailable {
+		t.Errorf("status = %d, want %d", status, http.StatusServiceUnavailable)
+	}
+}

test/integration/features/chromium_convert_url.feature

@@ -1401,3 +1401,19 @@ Feature: /forms/chromium/convert/url
     Then the response header "Content-Type" should be "application/pdf"
     Then there should be 1 PDF(s) in the response
     Then the "foo.pdf" PDF should have 1 page(s)
+
+  # chrome://crash makes the renderer crash deterministically, the same
+  # failure class as a renderer crash triggered by the page content. The
+  # request must fail fast with a 503 instead of hanging until the API
+  # timeout.
+  # See https://github.com/gotenberg/gotenberg/issues/1640.
+  Scenario: POST /forms/chromium/convert/url (Chromium crash fails fast with 503)
+    Given I have a default Gotenberg container
+    When I make a "POST" request to Gotenberg at the "/forms/chromium/convert/url" endpoint with the following form data and header(s):
+      | url | chrome://crash | field |
+    Then the response status code should be 503
+    Then the response header "Content-Type" should be "text/plain; charset=UTF-8"
+    Then the response body should contain string:
+      """
+      Chromium crashed while processing the request
+      """