README.md

Kq

Modern cross-platform JSON processor with readable Kotlin syntax.

cat ~/Desktop/bdb.ndjson | kq '.filter{it.bool("muted")}.sortedBy{it.long("size")}.take(7)'

Usage

1. You need jvm16 installed.
2. Download release.
3. Now you can run it, for example with example.ndjson file:

   java -jar kq.jar example.ndjson 'where{long("size") > 10} max{long("size")} select{int("id")}'
   # or
   cat example.ndjson | java -jar kq.jar 'where{long("size") > 10} max{long("size")} select{int("id")}'

4. On Unix you can create command kq:

   mv kq.jar /usr/local/bin/kq.jar
   echo "java -jar /usr/local/bin/kq.jar \$@" > /usr/local/bin/kq
   chmod a+x /usr/local/bin/kq

Examples

kq file.ndsjon 'max {long("size")} top 3 where {bool("active")}'

cat file.ndjson | kq 'top 5 where{!bool("active")} min{int("some")}'

kq file.ndsjon 'top 5 min{between(time("first"), time("last"))}'

cat file.ndjson | kq 'where { obj("arr").int(0) > 5 }'

kq file.ndsjon 'where{!bool("broken")} top 3 min{ obj(4).obj("nested").bool("flag") }'

Usage with Docker

Start the container in current directory, for example, with example.ndjson file:

docker run -v `pwd`:`pwd` -w `pwd` -it --rm demidko/kq example.ndjson 'where{bool("active")} max{long("size")} top 10'

Documentation

Any request contains control constructs and inline expressions.

Constructs

You can use any Kotlin sequence extension and following infix extensions in any order:

/* Sequence containing only elements matching the given predicate expression. */
where { /* expression */ }

/* Sequence sorted according to natural sort order of the value returned by specified selector expression. */
min { /* expression */ }

/* Sequence sorted descending according to natural sort order of the value returned by specified selector expression. */
max { /* expression */ }

/* Sequence containing first n elements. */
top(n)

/* Sequence containing the results of applying the given transform expression to each element in the original sequence */
select { /* expression */ }

Expressions

You can use any Kotlin expression and following functions:

/* Subnode of current json node */
obj(name: String)
obj(idx: Int)

/* Logic value of current json node */
bool(name: String)
bool(idx: Int)

/* Integer number of current json node */
int(name: String)
int(idx: Int)

/* Double  number of current json node */
double(name: String)
double(idx: Int)

/* Text value of current json node */
text(name: String)
text(idx: Int)

/* LocalDateTime value of current json node */
time(name: String)
time(idx: Int)

Build

Build Unix command

You need jvm16 installed. Run ./install.sh. Now you can run command, for example:

cat example.ndjson | kq 'where{bool("active")} top 10'

Build Java utility

Execute command:

./gradlew clean build

Your jar will be located at ./build/libs with -all.jar postfix. Now you can run jar, for example:

cat example.ndjson | java -jar kq-all.jar 'where{bool("active")} top 10'

Build Docker image

Execute command

docker build . -t kq

Now you can run container, for example:

docker run -v `pwd`:`pwd` -w `pwd` -it --rm kq example.ndjson 'where{bool("active")} top 10'

Build cross-platform utility with GraalVM

Execute following commands:

./gradlew clean build
native-image --allow-incomplete-classpath -jar ./build/libs/*-all.jar

Your native utility without runtime dependencies will be located at current directory with -all postfix. Now you can run utility, for example:

cat example.ndjson | ./kq-all 'where{bool("active")} top 10'