An example ENSEMBL gene ID identifier list:

ENSGALG00000026853
ENSGALG00000028376
ENSGALG00000004414
ENSGALG00000023751
ENSGALG00000029168
ENSGALG00000006729
ENSGALG00000005122
ENSGALG00000010145
ENSGALG00000027778
ENSGALG00000003548				

Will output:

ENSGALG00000026853	FGF3
ENSGALG00000028376	FGF19
ENSGALG00000004414	LUZP2
ENSGALG00000023751	CYP26C1
ENSGALG00000029168	TMEM27
ENSGALG00000006729	CYP26A1
ENSGALG00000005122	MYO1H
ENSGALG00000010145	MDGA1
ENSGALG00000027778
ENSGALG00000003548	BAIAP2L1

			

GET request for a single ID:

https://biotools.fr/chicken/ensembl_symbol_converter/?api=1&id=ENSGALG00000026853
will output:

{"ENSGALG00000026853":"FGF3"}

POST request with ids submitted as a JSON array:

endpoint:	https://biotools.fr/chicken/ensembl_symbol_converter/
POST variables:
	api = 1
	ids = ["ENSGALG00000026853","ENSGALG00000028376","ENSGALG00000027778"]

Will output:

{"ENSGALG00000026853":"FGF3","ENSGALG00000028376":"FGF19","ENSGALG00000027778":null}

Example R code:

require(httr)
require(jsonlite)

###
# A single ID to convert - use a GET request
###
url = "https://biotools.fr/chicken/ensembl_symbol_converter/?api=1&id=ENSGALG00000026853"
r <- GET(url)

output = fromJSON( content(r, "text"), flatten=TRUE)
df <- as.data.frame(output)
df


###
# Multiple IDs to convert - use a POST request
###
url = "https://biotools.fr/chicken/ensembl_symbol_converter/"
ids = c("ENSGALG00000026853","ENSGALG00000028376","ENSGALG00000027778")
ids_json <- toJSON(ids)

body <- list(api=1, ids=ids_json)
r <- POST(url, body = body)

output = fromJSON( content(r, "text"), flatten=TRUE)
df <- as.data.frame(output)
df