Adds code for the --length option of obiannotate

pkg/obitools/obiannotate/obiannotate.go

@@ -55,6 +55,16 @@ func AddTaxonAtRankWorker(taxonomy *obitax.Taxonomy, ranks ...string) obiseq.Seq
 	return f
 }
 
+func AddSeqLengthWorker() obiseq.SeqWorker {
+	f := func(s *obiseq.BioSequence) *obiseq.BioSequence {
+		s.SetAttribute("seq_length", s.Len())
+		return s
+	}
+
+	return f
+
+}
+
 func CLIAnnotationWorker() obiseq.SeqWorker {
 	var annotator obiseq.SeqWorker
 	annotator = nil
@@ -80,6 +90,11 @@ func CLIAnnotationWorker() obiseq.SeqWorker {
 		annotator = annotator.ChainWorkers(w)
 	}
 
+	if CLIHasSetLengthFlag() {
+		w := AddSeqLengthWorker()
+		annotator = annotator.ChainWorkers(w)
+	}
+
 	return annotator
 }
 

pkg/obitools/obiannotate/options.go

@@ -128,3 +128,7 @@ func CLIHasTaxonAtRank() bool {
 func CLITaxonAtRank() []string {
 	return _taxonAtRank
 }
+
+func CLIHasSetLengthFlag() bool {
+	return _setSeqLength
+}