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API
Mervis SCADA offers open REST-like API based on JSON and XML data formats. For full description please contact our technical support.
Important: Only officially supported response format is XML!
List of basic API methods
Function | Description |
---|---|
api/checkCredentials | |
api/logout | |
api/get/projects | |
api/get/projectData | |
api/get/projectByParts | |
api/get/history | |
api/get/history/specific | |
api/set/history | |
api/get/values | |
api/get/alarms | |
api/get/alarmHistory | |
api/get/eventHistory | |
api/get/changes | |
api/set/executeActions | |
api/set/values | |
api/set/executeAlarmOps | |
api/set/projectPriorityRefresh | |
api/get/schema | |
api/get/schema/datapoints | |
api/get/schema/values | |
api/get/schema/image |
Example
api/checkCredentials
Request
- URL: /api/checkCredentials?format=xml
- Method: POST
Request
{"cred":{"n":"demo","p":"demo"}}
Response
<?xml version="1.0" encoding="utf-8"?> <checkCredentialsResult xmlns:r="http://dev.rcware.eu/serialization/references" d="GlobalDomain" l="demo" t="2:85be00d3-5875-4dec-a9b4-c98e2ff2acbe" xmlns="http://dev.rcware.eu/auth" />
- You should use the received token t in subsequent API calls.
api/get/history
Request
- URL: /api/get/history?format=xml
- Method: POST
{ "cred":{ "n":"demo", //username "p":"demo" //password }, "projId":"5abf8ca0-94ba-48df-8d3c-7ebe87a12fd0", //project ID "dpId":"62cf4083-31ed-4bc1-be25-044ba837a9f0", //single datapoint ID "from":"/Date(1541199600000)/", //UTC in ms "to":"/Date(1541496190357)/", //UTC in ms "offset":0, "count":5000, "historyState":"" //client has to send historyState value from the last response with the following request }
Response
<?xml version="1.0" encoding="utf-8"?> <getHistoryResult xmlns:r="http://dev.rcware.eu/serialization/references" r:type="b133774d-21ce-42b6-add3-57c012079c55" xmlns:n1="http://dev.rcware.eu/scada/basic-props" xmlns="http://dev.rcware.eu/scada/history"> <!-- @Interval - ISO interval of trend values defined by the database client. @historyState - to be copied into the next request @nextValOfs - to be copied into the next request until value -1 is reached. If ts of value in not within the interval time span after the previous value's gt - some data is missing. --> <hist projId="5abf8ca0-94ba-48df-8d3c-7ebe87a12fd0" dpId="62cf4083-31ed-4bc1-be25-044ba837a9f0" propName="Output" interval="PT3M" historyState="" nextValOfs="-1"> <errMsg/> <vals> <!--ts - time stamp, gt - good through, value is valid in the whole time span between these two--> <hv ts="2018-11-02T21:26:08.7936747Z" gt="2018-11-03T20:35:08.8060769Z"> <n1:v>12754</n1:v> </hv> <hv ts="2018-11-03T20:41:09.0100479Z" gt="2018-11-05T11:35:08.7415158Z"> <n1:v>12754</n1:v> </hv> <hv ts="2018-11-05T11:40:04.0077949Z" gt="2018-11-05T17:25:03.4285643Z"> <n1:v>12754</n1:v> </hv> <hv ts="2018-11-05T17:28:03.4133447Z" gt="2018-11-05T19:40:03.0246122Z"> <n1:v>12755</n1:v> </hv> <hv ts="2018-11-05T19:43:03.6499981Z" gt="2018-11-05T22:01:03.2620552Z"> <n1:v>12756</n1:v> </hv> <hv ts="2018-11-05T22:04:03.1530787Z" gt="2018-11-06T02:37:03.454926Z"> <n1:v>12757</n1:v> </hv> <hv ts="2018-11-06T02:40:03.61157Z" gt="2018-11-06T04:52:03.1759539Z"> <n1:v>12758</n1:v> </hv> <hv ts="2018-11-06T04:55:03.14511Z" gt="2018-11-06T06:40:03.8621601Z"> <n1:v>12759</n1:v> </hv> <hv ts="2018-11-06T06:43:03.2063072Z" gt="2018-11-06T08:55:03.3019409Z"> <n1:v>12760</n1:v> </hv> <hv ts="2018-11-06T08:58:03.083875Z" gt="2018-11-06T09:10:03.0695797Z"> <n1:v>12761</n1:v> </hv> <hv ts="2018-11-06T09:13:03.5389214Z" gt="2018-11-06T09:19:03.5238805Z"> <n1:v>12761</n1:v> </hv> <!-- value without gt - ts and gt are equal--> <hv ts="2018-11-06T09:22:03.9461503Z"> <n1:v>12761</n1:v> </hv> </vals> </hist> </getHistoryResult>
api/set/history
Request
- URL: /api/set/history?format=xml
- Method: POST
Attribute i sets interval (ISO 8601) in which the next value should be expected to be saved into a database.
Even though there could be used name and password in cred - you should always use token to get the best performance.
All date and time values are supposed to be in UTC.
<?xml version="1.0" encoding="UTF-8"?> <setHistoryRequest xmlns="http://dev.rcware.eu/scada/history" xmlns:n2="http://dev.rcware.eu/auth" xmlns:n1="http://dev.rcware.eu/scada/basic-props" projId="5abf8ca0-94ba-48df-8d3c-7ebe87a12fd0" dpId="e86dba6d-1250-4e7f-aafb-84fd28324710"> <n2:cred t="xxxxx"/><!-- token should be used here --> <vals> <hv ts="2020-03-15T11:00:00+00:00" i="P1D"> <n1:v>2.7</n1:v> </hv> <hv ts="2020-03-16T11:00:00+00:00" i="P1D"> <n1:v>3.0</n1:v> </hv> <hv ts="2020-03-17T11:00:00+00:00" i="P1D"> <n1:v>2.0</n1:v> </hv> <hv ts="2020-03-18T11:00:00+00:00" i="P1D"> <n1:v>2.3</n1:v> </hv> </vals> </setHistoryRequest>
Response
- 200 OK
api/set/executeActions
Request
- URL: /api/set/executeActions?format=xml
- Method: POST
<?xml version="1.0" encoding="UTF-8"?> <executeActionsRequest xmlns="http://dev.rcware.eu/scada/action-defs" xmlns:n2="http://dev.rcware.eu/scada/basic-props" xmlns:n1="http://dev.rcware.eu/auth" xmlns:r="http://dev.rcware.eu/serialization/references"> <n1:cred n="userName" p="password"/> <actionDefs projId="5abf8ca0-94ba-48df-8d3c-7ebe87a12fd0"> <actions> <actionDefItem propName="INIT" dpId="afc22e18-f8e4-4e08-899c-fb9e4759df3d"> <execParam r:type="495c9644-eed1-4b94-933b-3fae702a9aca"> <n2:value>16</n2:value> </execParam> </actionDefItem> <actionDefItem propName="ZAP" dpId="34306c80-73f1-4465-ab51-2b2c1e85ab70"> </actionDefItem> </actions> </actionDefs> </executeActionsRequest>
Response
<?xml version="1.0" encoding="utf-8"?> <executeActionsResponse xmlns:r="http://dev.rcware.eu/serialization/references" code="Ok" message="OK" xmlns="http://dev.rcware.eu/scada/error-reporting" />
Matlab Client
General notes client function parameters
- parameter names ID and Guid are used interchangeably in the Matlab client, it is always a universally unique identifier referring to project or a particular datapoint
- when plural is used, array of guids is expected (ie. {'guid1', 'guid2'}), otherwise just one guid is expected (ie. 'guid1')
Data download example
scada = ScadaClient('https://scada.mervis.info/','demo','demo'); dataPointIDs = {'acad79f3-3358-42dd-9b74-98733e63d771','1afa7d9b-1183-4ab1-a6b1-18e464ae2d4d','e496bb8c-14ce-4c2c-b53b-3b71daeabca6'}; projectId = '5abf8ca0-94ba-48df-8d3c-7ebe87a12fd0'; chartLegend = {'/Plynová kotelna/ÚT1 - SEVER/TEPLOTA UT1','/Plynová kotelna/ÚT1 - SEVER/TEPLOTA UT1 zpátečka','/Plynová kotelna/ÚT1 - SEVER/Poloha ventilu'}; from = now - 4; to = now; timeSpan = 300; %sec [data, time] = scada.getData(projectId, dataPointIDs, from, to, timeSpan); plot(time,data); legend(chartLegend); datetick;
ScadaClient
ScadaClient(url, username, password)
Constructor of Mervis API wrapper.
findAllDPsWithReqTags
findAllDPsWithReqTags(projIds, tags)
Returns list of datapoints based on tags query. Example of tags definition: {'label','indoor_air_temperature';'room_type','office'}
saveData
saveData(projID, dpID, time, data)
Saves data into the Mervis database.
deleteVariable
deleteVariable(projGuid, dpGuid, from, to)
Deletes data of one variable based on from - to interval. If from - to is not defined, all data are deleted. Use carefully, there is no undo!
setDataPointValue
setDataPointValue(projGuid, dpGuid, value, buttonName)
Sets data point value using a button (primary the INIT button). Only numerical values are supported. Parameter buttonName is not mandatory. Value 'INIT' is used if buttonName is not defined.
Example:
dpGuid = 'ccaacb77-295b-48a8-a712-3fb272aa9b6f'; projectId = '6b65447e-8622-4a0d-b3b9-42f1d905fdaa'; buttonName = 'INIT' %see action ("button") name in Mervis SCADA GUI newValue = 1; scada = ScadaClient('https://scada.mervis.info/','username','password'); scada.setDataPointValue(projectId, dpGuid, newValue, buttonName)
getData
[data, time, dataInCell, info] = getData(projID,dpsIds,from,to,span,zone,doublesInterpolationMethod, interpolate_gaps_shorter_than)
Downloads data. Span is a sampling interval in seconds, default is 300 sec. Zone is time zone 'local' or 'utc' is applied to from/to parameters as well as to output time, default is 'local'. DoubleInterpolationMethod is same as e.g. interp1, applied to double values only the other types use method 'previous'. Interpolate_gaps_shorter_than - interpolates missing values periodes that are not shorer than this parameter (in seconds). Return parameters: data - downloaded data resampled, NaN is used for missing values; time - datenum time axis according to selected zone; dataInCell - usefull for strings; info - summary info about the request.
getDpTags
getDpTags(projectId, DpId)
Returns tags of the particular datapoint.
getAllProjectDPs
getAllProjectDPs(projectGuid)
Returns project IDs and names that are accessible to logged user.