Perform a feature analysis

A feature analysis is the process of using the spatial analysis service to perform server-side geometric and analytic operations on feature data. All feature analysis requests are job requests. The easiest way to programmatically run an analysis request to the spatial analysis service is to use ArcGIS REST JS, which provides a Job class that handles long- running operations.

In this tutorial, you use ArcGIS REST JS to perform a hot spot analysis to find statistically significant clusters of parking violations.

Prerequisites

You need the following to access the spatial analysis service and perform feature analysis operations:

  • An ArcGIS Online account.
  • A registered application to obtain its Client ID.
  • The redirect URL of the registered application to sue for authentication in the format "https://<server>[:port]" as in: https://localhost:8080.

Steps

Download the starter code

Download the tutorial starter code zip file from ArcGIS Online.

The zip file contains the following:

  • feature-analysis.html
  • authenticate.html

The feature-analysis.html file contains basic HTML scaffolding and the OAuth 2.0 code necessary to perform the analysis. The authenticate.html file is the callback page used as part of the authentication process.

Configure authentication

To access the spatial analysis service, you need an ArcGIS Online account and provide authentication using ArcGIS identity, which creates a temporary token using OAuth 2.0 protocol. API keys are not supported.

Use the ArcGISIdentityManager class to configure ArcGIS identity authentication. To learn more, go to the Authentication chapter.

  1. Go to the developer dashboard > OAuth2.0 tab and copy your application's Client ID.

  2. In the feature-analysis.html file, replace YOUR_CLIENT_ID with your Client ID.

    Expand
    Use dark colors for code blocks
                                                                                                                                                                                                                                                                                                             
    Change line
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
          let session = null;
          let lastResultUrl = null;
    
          const clientId = 'YOUR_CLIENT_ID';
    
    
          const signInLabel = "Sign in";
    
          const modalText = "To perform feature analysis you need an ArcGIS Online account. Learn more in <a href='https://developers.arcgis.com/documentation/mapping-apis-and-services/spatial-analysis/feature-analysis/introduction/#limitations'>Limitations.</a>"
    
    Expand
  3. In the authenticate.html file, replace YOUR_CLIENT_ID with your Client ID.

    Expand
    Use dark colors for code blocks
                         
    Change line
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
        <script type="module">
          import { ArcGISIdentityManager } from 'https://cdn.skypack.dev/@esri/arcgis-rest-request@4.0.0';
    
          const clientId = "YOUR_CLIENT_ID";
    
          const redirectUri = "authenticate.html";
          ArcGISIdentityManager.completeOAuth2({
            clientId,
            redirectUri
          })
        </script>
    
    Expand
  4. Run the application and navigate to your localhost, for example https://localhost:8080.

You should be able to click the Sign in button and successfully log in to an ArcGIS Online account.

Get the analysis URL

To make a request to the spatial analysis service, you need to get the URL first. The analysis service URL is unique to your organization.

  1. Call the getSelf operation from ArcGIS REST JS to obtain the analysis URL.

    Expand
    Use dark colors for code blocks
                                                                                                                                                                                                                                                                                                             
    Add line.Add line.Add line.Add line.Add line.Add line.Add line.
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
          const getAnalysisUrl = async (withAuth) => {
            const portalSelf = await getSelf({
              authentication: withAuth,
            });
    
            return portalSelf.helperServices.analysis.url;
          };
    
    
          document
            .getElementById('withPopupButton')
            .addEventListener('click', getAuth);
    
    Expand

Make the request

Use the Job class and set the operationURL and params required for the selected analysis.

  1. Create a function that submits a Job request to the spatial analysis service using your organization's analysis URL. Set the params required for a hot spot analysis and authenticate using the session token.

    Expand
    Use dark colors for code blocks
                                                                                                                                                                                                                                                                                                             
    Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
          const getAnalysisUrl = async (withAuth) => {
            const portalSelf = await getSelf({
              authentication: withAuth,
            });
    
            return portalSelf.helperServices.analysis.url;
          };
    
          const runAnalysis = async () => {
            const analysisUrl = await getAnalysisUrl(session);
            const operationUrl = `${analysisUrl}/FindHotSpots/submitJob`;
            const params = {
              analysisLayer: { url: points },
              shapeType: 'Hexagon',
              outputName: {
                serviceProperties: {
                  name: `RestJS_find_hot_spots_${new Date().getTime()}`,
                },
              }, //Outputs results as a hosted feature serivce.
            };
    
            const jobReq = await Job.submitJob({
              url: operationUrl,
              params: params,
              authentication: session,
            });
    
            // listen to the status event to get updates every time the job status is checked.
            jobReq.on(JOB_STATUSES.Status, (jobInfo) => {
              console.log(jobInfo.status);
            });
    
            // get all the results, this will start monitoring and trigger events
            const jobResp = await jobReq.getAllResults();
    
            // jobResp.aggregatedLayer.value.url
            return jobResp;
          };
    
    Expand
  2. Call the runAnalysis function to run the operation.

    Expand
    Use dark colors for code blocks
                                                                                                                                                                                                                                                                                                             
    Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
            const clearResults = () => {
                document.getElementById('clearResultsBtn').disabled = true;
                document.getElementById('runAnalysisBtn').disabled = false;
                document.getElementById('resultsCBox').checked = false;
            };
    
          const runAnalysisBtnWasClicked = (evt) => {
            document.getElementById('runAnalysisBtn').hidden = true;
            document.getElementById('progressBar').hidden = false;
            document.getElementById('withPopupButton').disabled = true;
    
            runAnalysis().then(
              (results) => {
                document.getElementById('runAnalysisBtn').hidden = false;
                document.getElementById('progressBar').hidden = true;
                document.getElementById('withPopupButton').disabled = false;
    
              },
              (err) => {
                console.log(err);
                document.getElementById('progressBar').hidden = true;
                document.getElementById('runAnalysisBtn').hidden = false;
                document.getElementById('withPopupButton').disabled = false;
                showAlert(err);
              }
            );
    
          };
    
    Expand

Handle the results

The results of a feature analysis are returned as feature data.

  1. Access the URL of the resulting hosted feature layer.

    Expand
    Use dark colors for code blocks
                                                                                                                                                                                                                                                                                                             
    Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    40
    41
    42
    43
    44
    45
    46
    47
    48
    49
    50
    51
    52
    53
    54
    55
    56
    57
    58
    59
    60
    61
    62
    63
    64
    65
    66
    67
    68
    69
    70
    71
    72
    73
    74
    75
    76
    77
    78
    79
    80
    81
    82
    83
    84
    85
    86
    87
    88
    89
    90
    91
    92
    93
    94
    95
    96
    97
    98
    99
    100
    101
    102
    103
    104
    105
    106
    107
    108
    109
    110
    111
    112
    113
    114
    115
    116
    117
    118
    119
    120
    121
    122
    123
    124
    125
    126
    127
    128
    129
    130
    131
    132
    133
    134
    135
    136
    137
    138
    139
    140
    141
    142
    143
    144
    145
    146
    147
    148
    149
    150
    151
    152
    153
    154
    155
    156
    157
    158
    159
    160
    161
    162
    163
    164
    165
    166
    167
    168
    169
    170
    171
    172
    173
    174
    175
    176
    177
    178
    179
    180
    181
    182
    183
    184
    185
    186
    187
    188
    189
    190
    191
    192
    193
    194
    195
    196
    197
    198
    199
    200
    201
    202
    203
    204
    205
    206
    207
    208
    209
    210
    211
    212
    213
    214
    215
    216
    217
    218
    219
    220
    221
    222
    223
    224
    225
    226
    227
    228
    229
    230
    231
    232
    233
    234
    235
    236
    237
    238
    239
    240
    241
    242
    243
    244
    245
    246
    247
    248
    249
    250
    251
    252
    253
    254
    255
    256
    257
    258
    259
    260
    261
    262
    263
    264
    265
    266
    267
    268
    269
    270
    271
    272
    273
    274
    275
    276
    277
    278
    279
    280
    281
    282
    283
    284
    285
    286
    287
    288
    289
    290
    291
    292
    293
    294
    295
    296
    297
            const getResults = () => {
            // You can use this URL to display the results on a map with ArcGIS API for JavaScript or an open source mapping API.
            console.log(lastResultUrl)
            document.getElementById('clearResultsBtn').disabled = false;
            document.getElementById('runAnalysisBtn').disabled = true;
            };
    
            const clearResults = () => {
                document.getElementById('clearResultsBtn').disabled = true;
                document.getElementById('runAnalysisBtn').disabled = false;
                document.getElementById('resultsCBox').checked = false;
            };
    
          const runAnalysisBtnWasClicked = (evt) => {
            document.getElementById('runAnalysisBtn').hidden = true;
            document.getElementById('progressBar').hidden = false;
            document.getElementById('withPopupButton').disabled = true;
    
            runAnalysis().then(
              (results) => {
                document.getElementById('runAnalysisBtn').hidden = false;
                document.getElementById('progressBar').hidden = true;
                document.getElementById('withPopupButton').disabled = false;
    
                lastResultUrl = results.hotSpotsResultLayer.value.url;
                getResults();
    
              },
              (err) => {
                console.log(err);
                document.getElementById('progressBar').hidden = true;
                document.getElementById('runAnalysisBtn').hidden = false;
                document.getElementById('withPopupButton').disabled = false;
                showAlert(err);
              }
            );
    
          };
    
    Expand

Run the app

Run the application and navigate to your localhost, for example: https://localhost:8080.

When you click Run analysis button, you submit a request to the spatial analysis service to perform a hot spot analysis. When the job is complete, you can use the URL of the resulting feature layer in the app. The metadata of the layer will look something like this:

What's next?

To learn how to perform other types of feature analysis, go to the related tutorials in the Mapping APIs and location services guide:

Your browser is no longer supported. Please upgrade your browser for the best experience. See our browser deprecation post for more details.