I am trying to write a JavaScirpt/Python script to pre-seed vector tiles. My plan is to gather data from a PostGIS database and generate tiles with mapnik, but I don't know how to finally save them into a file.
For Javascript, tippecanoe to generate mbtiles from GeoJSON, which can be easily generated from PostGIS.
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I am struggling to apply text redaction in a PDF file in a aws lambda function written in NodeJs. Here is a list of libraries that I have tried with no success:
pdf-lib: This library almost fulfils all the requirements except that it doesn't redact the text permanently as part of its limitations https://github.com/Hopding/pdf-lib/issues/827
PDF.js: To overcome the above limitation, tried to covert the pdf to an image, so the redaction black boxes are applied permanently. Example code here: https://github.com/mozilla/pdf.js/blob/master/examples/node/pdf2png/pdf2png.js However, this lib is not reliable as this cannot extract contents from most pdfs during the process.
Finally, Pdf2Pic: This library helps to overcome the limitation of the first library (pdf-lib) by the converting the pdf into images. But this library internally uses two non node based libraries (graphicsmagick and ghostscript) which I am trying to avoid.
Is there a nodejs based solution that can be used to apply redaction permanently on a pdf file or any solution that can be used to covert a pdf to images to overcome limitation of pdf-lib.
I am new to Solr, but I suppose that there is an easy way to index SVG files with Solr. I have installed Solr 6.3.0 and I am using an example 'files' core. It works well, but it seems that it parses the SVG files as plain text.
Is there an easy way to take only the texts between the text tags?
Ideally, I want to combine some meta data from a JSON file with the text from the SVG files. The JSON file looks like:
{
"id":"000001",
"title":"Some diagram",
...
} ...
The associated svg file is 000001.svg.Is there a way to create a scheme in Solr, that can take the fields from the json and merge a field with the text from the SVG file?
The most flexible way that will do what you want is to write a custom indexing utility that parses your JSON, picks up the SVG and extracts the relevant elements, then submits the complete structure to Solr. Depending on your programming language of choice you'll do this with something like SolrJ, Solrnet or another client library.
This is way more flexible and maintainable than integrating it directly into Solr, but if you want to do custom SVG indexing (without the additional JSON), you could use the XSLT support in the regular update handler, or using an XPathEntityProcessor in a DataImportHandler configuration.
My choice would be the custom indexing code.
I'm looking at adding an image to an existing PDF in Node.js. None of the PDF libraries I found appear to have the ability to modify an existing PDF though, so I'm planning on implementing it myself. I'm trying to figure out if it's too much work, as I can always do it server side using iTextPDF instead, but I'd prefer to do it in my app (Electron which uses Node.js).
If I just want to modify an existing PDF and add an image, will I have to write a complete rendering library or is PDF structured in such a way that I can write a very small parser that just gets the page I want and inserts an image using the correct format?
Specifically, I'm asking because I've previously looked into writing a text extraction library, put in order to get the position of text you have to render pretty much the entire PDF because of how positioning is handled. That's too much work to get around server side processing in this case.
To be clear, just asking if it's possible to do, not how to do it (don't want to be too broad, I'm sure I can figure that part out).
To perform a small manipulation of a PDF, you'll need to implement generalized reading, decompression, encryption and traversal of PDF data structures. Some of the thing you would need to handle include:
basic parsing of PDF syntax
indexing via the cross reference index, and/or cross reference index and object streams
objects (num, byte-string, hex string, dictionary, arrays, booleans...)
filters and variants (LZW, Flate, RunLength, Predictors)
encryption (RC4, AES, Custom security handlers)
page tree traversal
basic handling of page content streams
image handling
serialization, either rewriting of the entire PDF, or incremental updates to an existing PDF
Anything's possible, but realistically, you will need a PDF library or toolkit, client or server-side, to accomplish this.
I have dynamic data and need to split pages somewhere. Now I'm using "html-pdf" module and don't know how to do it.
I would like to write a command line program using Java that take in KML/Shapfile and output GeoJSON file.
What I usually did is go over ogre2ogre and manually convert my file.
Once I got the GeoJson I modified the content of it a little bit before output final GeoJSON.
I would like to skip the manual part and find some API that do the conversion for me.
Anyone could help please.
Thanks
OSMBonusPack provides a KML+GeoJSON toolkit, with both a KML parser/writer and a GeoJSON parser/writer, all in Java.
So this allows to read KML content, and write it as GeoJSON.
You can test this conversion using the demo app OSMNavigator.
It is targeting Android, so for your need you would have to pick the relevant classes, and remove code sections you don't need (icon loading, overlay building, Parcelable implementation, for instance).