Page History

...

Currently we have various REST endpoints (/ddl, /query, /update, /aql, /queryServicequery/service), which do similar things (parsing parameters out of the request parameters, assembling the response) but each endpoint does it in a slightly different manner. All of that should be refactored to use the common base endpoint. At the same time old endpoints could be kept for backwards-compatibility if that it really needed.
Current Web interface does the server-side HTML generation and does not use REST calls whatsoever. It would be better to eat our own dog food here and switch to assembling the result on the client side using JavaScript. Especially since we have a potential GSoC project proposal to build such JS-based interface.
As we are moving towards having more query languages under AsterixDB umbrella (AQL, SQL++, XQuery\/JSONiq as a part of VXQuery) it would be nice to design a generic language-agnostic REST API, which later could be reused by VXQuery since it's also lacking proper API as of now.

...

N1QL API	Value	Old Asterix API	Proposed API Parameter	Comment
results	JSONList	HTTP response body	results	One of 2 possible values 1) A list of all results returned by the query (mode=synchronous). 2) No value (statement is DDL/update/load)
-	URI	-	handle	A URI to Status endpoint (mode=asynchronous) or the Result endpoint (mode=asynchronous-deferred)
signature	JSONObject	-	signature	The schema of the results (if signature=true & format !=CSV)
status	string	HTTP response status	status	The status of the request; possible values are: success, running (async result), error (parse/optimizer error), fatal (execution error).
error	JSONObject	HTTP response body	error	An object containing details of the error
error.code	int	error-code	error.code	A code that identifies the error.
error.msg	string	summary	error.msg	A message describing the error in detail.
	string	stacktrace	error.stacktrace	A stack trace of the error.
metrics	JSONObject	-	metrics	An object containing details of the execution metrics.
metrics.executionTime	string	-	metrics.executionTime	The time taken for the execution of the request, i.e. time from when query execution started until the results were returned. (if mode=synchronous and execute-query=true)
metrics.resultCount	unsigned int	-	metrics.resultCount	The total number of objects in the results (if mode=synchronous and execute-query=true)
-	JSONObject	-	plans	(Optional) An object containing details of the execution plan at different stages.
-	JSONObject/string	-	plans.expr_tree	Serialized query expression tree (if expr-tree=true)
-	JSONObject/string	-	plans.rewritten_expr_tree	Serialized rewritten query expression tree (if rewritten-expr-tree=true)
-	JSONObject/string	-	plans.logical_plan	Serialized query logical plan (if logical-plan=true)
-	JSONObject/string	-	plans.optimized_plan	Serialized query optimized logical plan (if optimized-plan=true)
-	JSONObject/string	-	plans.hyracks_job	Serialized Hyracks job (if hyracks-job=true)

Examples:

DDL request

Code Block

title	Request

curl -v http://localhost:19002/query -X POST \
-d "statement=create dataverse test;"

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "success"
  "metrics": {
    "executionTime": "1ms"
  }
}

Query which is not executed, but returns logical plan

Code Block

title	Request

curl -v http://localhost:19002/query -X POST \
-d "statement=for $x in dataset testDS return $x & lossless=true & logical-plan=true & execute-query=false"

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "success"
  "metrics": {
    "executionTime": "5ms"
  },
  "plans": {
    "logical_plan": [
      {"operator": "distribute_result", "args": [{"exp": "var_ref", "var": "$$0"}]},
      {"operator": "datascan", "output_vars": ["$$0", "$$1"]}
    ]
  }
}

Query which synchronously returns CSV (with header) result inside JSON response

Code Block

title	Request

curl -v http://localhost:19002/query -X POST -H "Accept: text/csv" \
-d "statement=for $x in dataset Tweets return $x & signature=true"

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "success",
  "results": "'id','screen_name','message_text'\n'1','BarackObama','Four more years'"
  "metrics": {
    "executionTime": "10ms",
    "resultCount": 1
  }
}

Query which returns optimizer error

Code Block

title	Request

curl -v http://localhost:19002/query -X POST \
-d "statement=create dataset Tweets(TweetType) primary key facebook_id"

Code Block

title	Response

< HTTP/1.1 400 Bad Request
Content-Type: application/json
{
  "status": "error",
  "error": {
    "code": 1,
    "msg": "Field 'facebook_id' cannot be found in datatype 'TweetType'"
  }
  "metrics": {
    "executionTime": "1ms"
  }
}

Query which returns runtime error

Code Block

title	Request

curl -v http://localhost:19002/query -X POST \
-d "statement=create dataset Tweets(TweetType) primary key facebook_id"

Code Block

title	Response

< HTTP/1.1 500 Internal Server Error
Content-Type: application/json
{
  "status": "fatal",
  "error": {
    "code": 99,
    "msg": "Something happen during query execution",
    "stacktrace": "java.lang.RuntimeException: \n\r at java.lang.Thread.run(Thread.java:745)"
  }
  "metrics": {
    "executionTime": "1ms"
  }
}

Query which runs synchronously, however does not include them into response, but provides a handle to retrieve them. Request also specifies to include ADM type (signature).

Code Block

title	Request

curl -v http://localhost:19002/query -X POST \
-d "statement=for $x in dataset Tweets return $x & include-results=false & signature=true"

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "success",
  "resultshandle": "http://localhost:19002/results/071cde2e-0277-11e6-b512-3e1d05defe78",
  "signature": {
    "id": "int64",
    "screen_name": "string",
    "message_text": "string"
  },
  "metrics": {
    "executionTime": "10ms",
    "resultCount": 2
  }
}

Query which returns lossless-JSON results asynchronously and does not include them into response, but provides a handle to retrieve them.

Code Block

title	Request

curl -v http://localhost:19002/query -X POST -H "Accept: application/json" \
-d "statement=for $x in dataset Tweets return $x & lossless=true & mode=asynchronous & include-results=false"

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "running",
  "resultshandle": "http://localhost:19002/status/bd7a2b0e-0277-11e6-b512-3e1d05defe78"
  "metrics": {
  }
}

...

Query which returns runtime error

Code Block

title	Request

curl -v http://localhost:19002/status/bd7a2b0e-0277-11e6-b512-3e1d05defe78 -X GET

Code Block

title	Response

< HTTP/1.1 500 Internal Server Error
Content-Type: application/json
{
  "status": "fatal",
  "error": {
    "code": 99,
    "msg": "Something happen during query execution",
    "stacktrace": "java.lang.RuntimeException: \n\r at java.lang.Thread.run(Thread.java:745)"
  }
}

Query which is still executing

Code Block

title	Request

curl -v http://localhost:19002/status/bd7a2b0e-0277-11e6-b512-3e1d05defe78 -X GET

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "running"
}

Query which successfully completes and return URI to its results. Reffer to Query endpoint Example 7 to see the original request.

Code Block

title	Request

curl -v http://localhost:19002/status/bd7a2b0e-0277-11e6-b512-3e1d05defe78 -X GET

Code Block

title	Response

< HTTP/1.1 200 OK
Content-Type: application/json
{
  "status": "success",
  "resultshandle": "http://localhost:19002/results/c7e7daed-28cd-472f-890d-62e02909e5e9"
  "metrics": {
    "executionTime": 100ms,
    "resultCount": 10
  }
}

...

Page tree

Versions Compared

Old Version 12

New Version 13

Key

Examples: