API Overview

For development purposes graphiql is enabled, which will help you see the structure of the API and what you can query for, which will require your web manager username and password to login. For production users must go to /token with a json object having username and password fields like {"usename": "WMUser", "password":"password"}to get a user Token which need to be included as a header in all queries to API. header name:- Authorization: Token user token.

API Development screen is normally divided into two sections and the third section can be added by clicking Docs button at top right of the screen.

• First section: This is for writing your query.

  A graphQL query is like defining a structure of your json object.

  Sample query

  Querying for number of visits, ra and dec for 2017-1 targets.

  1 2 3 4 5 6 7 8 9 10 11

  { targets(semester: "2017-1"){ NVisits target{ targetcoordinates{ ra dec } } } }

  line 2: it will return the list of all 2017-2 targets
  line 3: number of visits for each target
  line 4-7: due to SDB structure, to get more details of the target. Click on Target field where there is a link to target Coordinates field where there are RA and DEC of that target
  To avoid Line 4-7 the auto mapping of the SDB don't have to map everything
• Second section: This section is for query results.
  GraphQL will return a json object of data with the structure you defined on your query section or json object of errors.
  Sample results for the above query
{
"data": {
"targets": [
{
"NVisits": 1,
"target": {
"targetcoordinates": {
"dec": x.x,
"ra": x.x
}
}
},
{
"NVisits": 2,
"target": {
"targetcoordinates": {
"dec": x.x,
"ra": x.x
}
}
},
.
.
.

• Third section: To see the depth of what you can query and the structure of API.
  This section will guide you in writing a GraphQL query and it will also show data type of what you are querying. Start by clickingQuery this will lead you to what you can query in a root field.
  
  
  How above query was created.

  1. Select Docs for Documentation Explorer
  2. Select Query to root query,
     A list of field will appear, this will be what can be queried on this field.
     • Look for field/s of interest in this case targets.
       targets(semester: String): [ProposalTarget]
       
     • targets require argument ("semester: String") which means you must provide a semester of type string when you are querying for targets
     • "[ProposalTarget]" square brackets means you will get a list of what is defined within it, in this case you will get a list of ProposalTarget
  3. Select ProposalTarget to see what fields it contains.
     
     • One of the fields of ProposalTarget is of interest, which is NVisits of type INT. It is then added to the query
     • RA and DEC are in target: Target Field in target >> targetcoordinates >> ra and dec which are float