Moving documentation

documentation/jq.md

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+# JQ
+
+## Piping into jq
+
+You can `cat` or `bat` a file and pipe it into `jq`.
+
+You can also take a command that returns json and pipe it into `jq`.
+
+## Returning data without "
+
+To return data without `jq` wrapping results in `"` use the `-r` flag.
+
+`jq -r`
+
+## Filtering
+
+### Get values from a key
+
+Running `aws --profile admin cloudformation describe-stack-resources --stack-name strapi-vpc | jq` returns:
+
+```json
+{
+  "StackResources": [
+    {
+      "StackName": "strapi-vpc",
+      "StackId": "arn:aws:cloudformation:eu-west-1:745437999005:stack/strapi-vpc/a9e41430-8afc-11ea-bdaa-0a736ea8438a",
+      "LogicalResourceId": "InternetGateway",
+      "PhysicalResourceId": "igw-0e059db8e0795ac32",
+      "ResourceType": "AWS::EC2::InternetGateway",
+      "Timestamp": "2020-04-30T16:07:42.434Z",
+      "ResourceStatus": "CREATE_COMPLETE",
+      "DriftInformation": {
+        "StackResourceDriftStatus": "NOT_CHECKED"
+      }
+    },
+    {
+      "StackName": "strapi-vpc",
+      "StackId": "arn:aws:cloudformation:eu-west-1:745437999005:stack/strapi-vpc/a9e41430-8afc-11ea-bdaa-0a736ea8438a",
+      "LogicalResourceId": "InternetGatewayAttachment",
+      "PhysicalResourceId": "strap-Inter-1413K0IDR1L3N",
+      "ResourceType": "AWS::EC2::VPCGatewayAttachment",
+      "Timestamp": "2020-04-30T16:08:00.147Z",
+      "ResourceStatus": "CREATE_COMPLETE",
+      "DriftInformation": {
+        "StackResourceDriftStatus": "NOT_CHECKED"
+      }
+    },
+```
+
+We can then use `jq`'s filtering to return values.
+
+We have a key of `StackResources` which contains a list: `.StackResources[]`
+
+We can then pass in the key we want `.StackResources[].PhysicalResourceId`
+
+`aws --profile admin cloudformation describe-stack-resources --stack-name strapi-vpc | jq -r '.StackResources[].PhysicalResourceId'` which gives:
+
+```json
+"igw-0e059db8e0795ac32"
+"strap-Inter-1413K0IDR1L3N"
+"strap-Publi-1TS82BV8W4UFD"
+"rtb-0cf8d05f71a30ef03"
+"subnet-051fe56dc37d8396d"
+"rtbassoc-0f7ae2fbdfe6bf2a5"
+"subnet-0ea9f2f165a57be27"
+"rtbassoc-00a67937c3778e273"
+"subnet-09b28d722f41b2dde"
+"rtbassoc-0a0a6bd0f8ff641df"
+"vpc-029d232726cbf591d"
+```
+
+`aws --profile admin cloudformation describe-stack-resources --stack-name strapi-vpc | jq -r '.StackResources[] | .ResourceType + ":    " + .PhysicalResourceId'`