Unable to get image export to work using docker (docker-compose)

This is likely to be a user-error, though perhaps it could lead to improved documentation.

My long term goal is to export each of the layers in a local file as an image that can be pasted into a PowerPoint (sigh) slide.

I'd really appreciate a minimal example, perhaps starting from docker-compose up and a URL to curl or ....

I'm working on a Mac, using Rancher desktop configured to use Docker/moby bits on the backend (e.g. as a license-free version of Docker Desktop for the Mac).

I've tried both the image-export and self-contained docker-compose configurations.

When I clone the project, cd into the self-contained subdirectory and run docker-compose up I am able to point a browser at http://localhost:8080/ and use the GUI diagramming tool, so basic things seem to be ok.

I can't figure out how to use the export server. I'm starting from example 2 in the draw-image-export project. The direct version of it complains about illegal characters (path obfuscated):

$ curl 'http://localhost:8080/ImageExport4/export\?format\=png\&bg\=ffffff\&url\=file:///path/to/diagram.drawio'
<!doctype html><html lang="en"><head><title>HTTP Status 400 – Bad Request</title><style type="text/css">body {font-family:Tahoma,Arial,sans-serif;} h1, h2, h3, b {color:white;background-color:#525D76;} h1 {font-size:22px;} h2 {font-size:16px;} h3 {font-size:14px;} p {font-size:12px;} a {color:black;} .line {height:1px;background-color:#525D76;border:none;}</style></head><body><h1>HTTP Status 400 – Bad Request</h1><hr class="line" /><p><b>Type</b> Exception Report</p><p><b>Message</b> Invalid character found in the request target [&#47;ImageExport4&#47;export\?format\=png\&amp;bg\=ffffff\&amp;url\=file:&#47;&#47;&#47;path&#47;to&#47;diagram.drawio ]. The valid characters are defined in RFC 7230 and RFC 3986</p><p><b>Description</b> The server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).</p><p><b>Exception</b></p><pre>java.lang.IllegalArgumentException: Invalid character found in the request target [&#47;ImageExport4&#47;export\?format\=png\&amp;bg\=ffffff\&amp;url\=file:&#47;&#47;&#47;Users&#47;georgehartzell&#47;projects&#47;20231113-how-to-git&#47;developer-flow.drawio ]. The valid characters are defined in RFC 7230 and RFC 3986
    org.apache.coyote.http11.Http11InputBuffer.parseRequestLine(Http11InputBuffer.java:490)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:263)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:928)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1794)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
    org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
    org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.base&#47;java.lang.Thread.run(Unknown Source)
</pre><p><b>Note</b> The full stack trace of the root cause is available in the server logs.</p><hr class="line" /><h3>Apache Tomcat/9.0.82</h3></body></html>%

I've tried, w/out success, not escaping with backslashes the bits in the URL.

Thinking that the file:// URL was giving me trouble, I started a little python webserver in the directory with the diagram.drawio file and tried passing that in, which returns a different error, The requested resource [/ImageExport4/export] is not available:


$ curl 'http://localhost:8080/ImageExport4/export?format=png&bg=ffffff&url=http://localhost:8765/diagram.drawio'
<!doctype html><html lang="en"><head><title>HTTP Status 404 – Not Found</title><style type="text/css">body {font-family:Tahoma,Arial,sans-serif;} h1, h2, h3, b {color:white;background-color:#525D76;} h1 {font-size:22px;} h2 {font-size:16px;} h3 {font-size:14px;} p {font-size:12px;} a {color:black;} .line {height:1px;background-color:#525D76;border:none;}</style></head><body><h1>HTTP Status 404 – Not Found</h1><hr class="line" /><p><b>Type</b> Status Report</p><p><b>Message</b> The requested resource [&#47;ImageExport4&#47;export] is not available</p><p><b>Description</b> The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.</p><hr class="line" /><h3>Apache Tomcat/9.0.82</h3></body></html>%

I would love hints, clues, suggestions, or fully working examples that will help me on my way.

Thanks!

jgraph / docker-drawio

Unable to get image export to work using docker (docker-compose) #130